JP2007038314A - Work assistance device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for facilitating an operation of moving a reference point fixed to an object along a target trajectory without meandering in a direction orthogonal to the target trajectory.
An applicator 30 and an operation element 18 are arranged in a moving mechanism 11 of a work assisting device 10 and the applicator 30 moves according to a force applied to the operation element 18. When the reference point P of the applicator 30 is moved along the target trajectory L on the workpiece W, the controller 22 performs the first side 42 and the second side on the virtual guide surface 40 and the virtual guide surface along the target trajectory L. Method 44 is set. When the projection position of the reference point P on the virtual guide surface coincides with the target trajectory L, a large operating resistance force FR is generated in the operator 18 in the direction from the first side 42 to the second side 44. The operator operates the operator 18 so as to move the reference point P along the target trajectory L while pressing the reference point P against the virtual guide surface 40. The reference point P can be moved along the target trajectory L without meandering in the direction orthogonal to the target trajectory L.
[Selection] Figure 1

Description

  The present invention relates to an apparatus for assisting a worker in moving a reference point set on an object such as a workpiece or a work implement along a target trajectory.

A mechanism for supporting an object such as a work or a work implement and moving the object using power of a motor or the like is known.
There is also known a technique that uses an operation element to indicate a movement position of an object to be moved by a movement mechanism. The operator can be operated by the operator, and when the operator operates the operator, the movement mechanism follows the operation. When the operator operates the operator to instruct the reference point fixed to the object to move along the target trajectory, the reference point of the object can be moved along the target trajectory. Since the object is moved using the power of a motor or the like, the operator can move the reference point fixed to the object along the target trajectory with a light operating force.

  A technique for guiding an operator's operation is also known. For example, impedance control is well known. Impedance control adds a resistance force application mechanism that applies operating resistance to the operating element, so that if the operating element is operated on the side where the reference point is off the target trajectory, a large force is required for the operation. Controls the operating resistance. When this guidance technique is used, it is easy to operate the operator so that the reference point moves along the target trajectory.

  There is also known a technique for providing a safety mechanism in this type of work auxiliary device. In Patent Document 1, a work area is provided on both sides of a target trajectory, and a limit area is provided on the outside thereof. Normal impedance control is performed while the reference point is within the work area. When the reference point moves out of the work area and enters the limit area, a strong force is applied to the operator to return to the work area. According to the technique of Patent Document 1, a light resistance force is obtained from the operator while an operation is performed so that the reference point is slightly deviated from the target trajectory, and when the operation is performed so that the reference point is greatly deviated from the target trajectory. Strong operating resistance can be obtained from the control. The former guides the operation along the target trajectory, and the latter prevents the reference point from moving out of the work area.

JP 2005-14133 A

With the technique of Patent Document 1, an operation along the target trajectory is guided, and an operation in a direction in which the reference point is out of the work area is regulated.
However, in the conventional technology, when guiding the operation along the target trajectory, the operation resistance cannot be obtained if the reference point is on the target trajectory. Resistance to an operation that deviates from the target trajectory is obtained only after deviating from the target trajectory.
As a result, the actually obtained trajectory tends to meander although it is along the target trajectory. In order to guide the operation along the target trajectory, it is difficult to guide so as not to meander in the method in which the operation resistance is applied to the operation element when the target trajectory is deviated.
The present invention solves that problem. The operator feels as if he / she is manipulating the controls following a ruler or template that has the shape of the target trajectory, and assists in moving the target along the target trajectory without meandering the object. Propose technology to do.

The work assisting device of the present invention assists the worker in moving the reference point fixed to the object along the target trajectory. The work assisting device is capable of supporting an object and moving the object using power, a position sensor for detecting the position of a reference point, a target trajectory storage means for storing a target trajectory, An operator operated by an operator to instruct the movement position of the reference point, a resistance applying mechanism for applying an operating resistance to the operator, an applying mechanism controller for controlling the resistance applying mechanism, and a moving mechanism A moving mechanism controller for controlling is provided.
The assigning mechanism controller sets a virtual guide surface including the target trajectory, and the target trajectory coincides with a position (referred to as a projection position) obtained by projecting the position of the reference point detected by the position sensor onto the virtual guide surface. Sometimes a large operating resistance force from one side of the target trajectory on the virtual guide surface to the other side is applied to the operating element by the resistance applying mechanism, and small when the projection position is on the other side of the target trajectory Gives operating resistance.
The movement mechanism controller controls the movement mechanism so as to move the object based on the resultant force of the operation force and the resistance force received by the operation element.
A plurality of virtual guide surfaces may be set for one target trajectory. Further, different virtual guide surfaces may be set for different portions of the target trajectory. In this case, each virtual guide surface only needs to include each portion of the target trajectory corresponding thereto.

The auxiliary device applies a large operating resistance force from one side of the target trajectory to the other side of the virtual guide surface when the projection position matches the target trajectory. When the operator is applying an operating force directed to one side of the target trajectory, it is difficult to move the projection position from the target trajectory to one side by receiving an operating resistance force from the operator. This means that the reference point matches the target trajectory when the operator is applying an operating force toward one side of the target trajectory. The movement mechanism controller controls the movement mechanism so as to move the object based on the resultant force of the operation force and the operation resistance force applied to the operation element.
According to the present auxiliary device, the operator does not need to adjust the operation position of the operation element that can freely move in the space to match the reference point with the target trajectory, and the worker points to one side of the target trajectory. At the same time, an operation force may be applied in a direction along the target trajectory.
When the projected position of the reference point coincides with the target trajectory, a large operating resistance force from one side of the target trajectory on the virtual guide surface to the other side is applied to the operator by the applying mechanism. It becomes difficult for the operator to move the projection position to one side of the target trajectory. As a result, the virtual guide surface serves as a ruler or template, and the operator performs an operation of moving the operator along the target trajectory while pressing against the ruler or template. The result is that the object moves smoothly (without meandering) along the target trajectory. When the reference point matches the target trajectory, the position of the reference point becomes the projection position as it is. If the operation resistance force from one side of the target track to the other side is applied when the reference point and the target track are coincident, the virtual path is virtually displayed on one side of the target track. It is possible to realize a state where there is a ruler and no ruler exists on the other side of the target trajectory.
The operation of the auxiliary device can be explained metaphorically as follows. For example, when tracing a target trajectory with a pen, it is easier to prepare a ruler or template that has the shape of the target trajectory and trace it against the ruler, etc., rather than tracing freehand.

In the work assistance device of the present invention, the relationship between the pen and the ruler is applied to move the reference point along the target trajectory. Specifically, a virtual guide surface including the target trajectory is set by the giving mechanism controller. The application mechanism controller also controls a resistance application mechanism that applies an operation resistance to the operator. When the projection position and the target trajectory coincide with each other, the imparting mechanism controller imparts a large operating resistance force from one side of the target trajectory on the virtual guide surface to the other side, and the projection position is When it is on the other side of the target trajectory, the resistance applying mechanism is controlled so that a small operating resistance is applied to the operator. A virtual ruler is realized by the applying mechanism controller and the resistance applying mechanism. A ruler extending along the target trajectory can be realized by the virtual guide surface. The operator only needs to perform the same operation as when the operator is moved along the ruler, and the reference point fixed to the object moves smoothly along the target trajectory. There is no meandering. According to the work assistance device of the present invention, the work of moving the reference point fixed to the object smoothly (without meandering) along the target trajectory is facilitated.
If the reference point fixed to the object is simply moved smoothly along the target trajectory, the moving mechanism can be automatically controlled. A moving device that does not require an operator can be configured. However, when moving the reference point fixed to the object to the target trajectory, the worker may want to instruct the moving speed or the like at the work site. In this case, the auxiliary device is particularly effective, and the operator can operate the operator to instruct the moving speed along the target trajectory.

  When the reference point is moved along the target trajectory, it means that both are moved relatively. This includes moving the reference point along the moving target trajectory as well as moving the object along the stationary target trajectory. For example, if the object is an adhesive applicator and an adhesive application line (target trajectory) is fixedly specified for the workpiece, and the workpiece moves, by moving the adhesive applicator, Adhesive can be applied along the moving target trajectory.

The applying mechanism controller applies a large frictional force to the resistance applying mechanism when the projection position is on one side of the target trajectory on the virtual guide surface, and is small to the resistance applying mechanism when on the other side of the target trajectory. It is preferable to apply a frictional force.
That is, when the projection position is on the other side of the target trajectory (the side where the ruler does not exist), the frictional force is small and the operator can be operated relatively freely, whereas the projection position is one of the target trajectories. When the operator is on the side (the side where the ruler is present), when the operator is operated in a direction away from the target trajectory, a large frictional force is applied, and the operation of the operator is strongly restricted. .

The moving mechanism and the resistance applying mechanism may be different. A separate moving mechanism may support and move the object, and the resistance applying mechanism may apply a resistance to the operation of the operation element provided in the resistance applying mechanism.
In this case, the moving mechanism requires a power device such as a motor, but the resistance applying mechanism can be realized by a brake or the like, and power is not necessarily required. If the moving mechanism is controlled based on the position of the operating element or the force applied to the operating element, the moving position of the reference point moved by the moving mechanism is controlled by the operating element operated by the operator.

On the other hand, the moving mechanism can also serve as a resistance applying mechanism. In this case, one rigid body on the moving mechanism supports both the object and the operation element. The relative positional relationship between the object and the operation element is unchanged, and the object is also moved as the operation element moves. A force sensor is interposed between the rigid body and the operation element so that the operation force applied by the operator can be detected. Note that “one rigid body” can be regarded as “one rigid body” when the plurality of rigid bodies are fixed so that their relative positions are not changed.
The whole auxiliary device can be made compact by the movement mechanism also serving as a resistance force applying mechanism. At the same time, since the object and the operation element move together, the operator only has to operate the operation element for the distance in which the object is to be moved in the desired direction. There is an advantage that the work becomes easier.

The movement mechanism controller has calculation means for calculating a motion that occurs when the force detected by the force sensor is applied to the virtual object, and controls the movement mechanism so as to realize the calculated movement at the reference point. It is preferable.
In this case, for example, it is calculated that an acceleration of 1.0 [m / sec ² ] is generated in a virtual object of 1.0 [kg] because an operating force of 1.0 [N] is applied. The moving mechanism realizes an acceleration of 1.0 [m / sec ² ] with respect to the reference point. Assuming that the actual object with a fixed reference point is 5.0 [kg], a force of 5.0 [N] is required to apply an acceleration of 1.0 [m / sec ² ] to a mass of 5.0 [kg]. To do. When the motor driving the moving mechanism outputs a force of 4.0 [N], the above result is obtained. In this case, an exercise of applying a force of 5.0 [N] to the object by extracting an auxiliary force of 4.0 [N] from an operation force of 1.0 [N] is realized. The operator receives a reaction force of 1.0 [N] (that is, an operation resistance force) from the operation element. Actually, an object of 5.0 [kg] can be operated as if it were an object of 1.0 [kg].

The calculation formula for calculating the motion that occurs when an operating force is applied to the virtual object includes at least a virtual friction force term that prevents the motion of the virtual object, and the projection position is on one side of the target trajectory on the guide surface. It is preferable that the virtual frictional force is set to a large value when it is in the direction and the virtual frictional force is set to a small value when it is on the other side of the target trajectory to calculate the motion generated in the virtual object.
A small virtual frictional force is set when the projection position is on the other side of the target trajectory in the guide surface (the side on which no virtual ruler exists). A small operation resistance force is applied to the force applied to the operator by the operator due to the small frictional force. When the projection position is on the other side of the target trajectory in the guide surface, the operator can be easily operated.
On the other hand, when the projection position is on one side of the target trajectory on the guide surface (the side on which the virtual ruler exists), a large virtual friction force is set. A large frictional force gives a large operation resistance to the operation force applied to the operator by the operator. When the projection position is on one side of the target trajectory on the guide surface, it is possible to make it difficult to operate the operator. As a result, when the operator moves the projection position from the other side of the target trajectory to one side, the operator receives a strong resistance from the operator when the projection position matches the target trajectory. The operator will feel as if the projection position is in contact with the ruler or template as if the projection position coincided with the target trajectory. In this state, the object can be moved smoothly (without meandering) along the target trajectory by operating the operation element so as to move the reference point in the direction along the target trajectory.

It is preferable that an upper limit value is provided for the operation resistance force from one side of the target track on the virtual guide surface to the other side.
The target trajectory instructed by the work assistance device may slightly deviate from the actual target trajectory due to an error in the work attachment position or the like. In such a case, the operator adjusts the operating force that presses the operating element against the virtual ruler. When the actual target trajectory is inside the virtual ruler, an operation force greater than the upper limit value is applied. As a result, the reference point can be moved to the virtual ruler side from the target trajectory and moved along the actual target trajectory. Even if the data of the target trajectory stored in the work assistance device is deviated from the actual target trajectory, the object can be moved along the actual target trajectory. Also at this time, the operator performs an operation of pressing the operation element against the virtual ruler. The reference point does not meander.

It is preferable that the applying mechanism controller calculates an operating resistance force at each of the two virtual guide surfaces that intersect in the target trajectory, and applies the resultant force to the operating element by the resistance applying mechanism. If the projection position on one guide surface coincides with the target trajectory L, the reference point P can be easily moved in the direction perpendicular to the guide surface. When two virtual guide surfaces intersecting with the target trajectory are set, a location where the projection position on each guide surface coincides with the target trajectory L is a position where the reference point P coincides with the target trajectory L. Therefore, the reference point P can be strongly restrained on the target trajectory L from two directions intersecting with the target trajectory L. In other words, the reference point P can be constrained two-dimensionally in the direction intersecting the target trajectory L.
This is illustrated using FIG. As schematically shown in FIG. 8, two virtual guide surfaces 92 and 94 that intersect with the target trajectory L are set. The resistance force applying mechanism calculates an operation resistance force on each of the two virtual guide surfaces 92 and 94 that intersect with the target track L and applies the resultant force. FIG. 8 schematically shows that the operating resistance 95 acts from one side of the target track L to the other side in the virtual guide surface 94 when the reference point P and the target track L coincide. It is illustrative. Further, when the reference point P and the target trajectory L coincide with each other, the operation resistance force 93 acts on the virtual guide surface 92 from one side of the target trajectory L to the other side. ing.
In this case, the reference point P is stabilized on the target trajectory L if the operator urges the reference point P positioned between the virtual guide surfaces 92 and 94 in the direction toward the target trajectory L. By setting the two virtual guide surfaces 92 and 94, it is possible to assist the movement of the reference point P along the target trajectory L while preventing the reference point P from meandering two-dimensionally in a plane intersecting the target trajectory L. can do.
When the reference point P and the target trajectory L coincide with each other, the projection position of the reference point P on the virtual guide surfaces 92 and 94 coincides with the position of the reference point P.

When the target track draws a curve, it is preferable that the resistance applying mechanism sets one side of the target track on the guide surface outside the curve.
The “outside of the curve” means the opposite side of the target trajectory with respect to the center position of the radius of curvature that defines the curve.
In this case, the operator urges the manipulator so as to press the reference point from the inside to the outside of the curve and also urges the manipulator in the direction along the target trajectory. The operation resistance acts to change the direction of the reference point to the inside of the curve along the target trajectory. It is possible to avoid a situation in which the force urged to the operator for moving the reference point in the direction along the target trajectory is excessively moved away from the virtual ruler to the other side of the target trajectory. .
In this specification, “when the target trajectory draws a curve” is used in a concept including the case where the target trajectory is bent.

  According to the work assisting device of the present invention, it is possible to provide a work assisting device that can be easily operated to move a reference point set on a target such as a workpiece or work implement along a target trajectory. In particular, the operation for smoothly moving the reference point along the target trajectory without making the reference point meander is simplified.

The main features of the examples are listed.
(First Mode) An upper limit value is provided for the operation resistance force from one side of the target track to the other side of the virtual guide surface, and one of the operation forces from the other side of the target track. When the operating force component directed to the side of the target track is smaller than the upper limit value, the operating resistance force directed from one side of the target track to the other side is set to the other side of the target track. Is set to the same magnitude as the operating force component directed from one side to the other.
As a result, when the operator moves the projection position from the other side of the target trajectory to one side, it seems as if it receives a large Coulomb friction force (static friction force) on one side of the target trajectory. The operation resistance can be felt from the operator. When the operating force is less than the static friction force, the projected position does not move further to one side of the target trajectory when it coincides with the target trajectory.
On the other hand, if the worker applies a working force exceeding the upper limit in the direction from the other side of the target track to one side, the operating force exceeds the static friction force, and the reference point is set to one of the target tracks. Can be moved to the side.
(2nd form) The upper limit is provided in the operation resistance force which goes to the other side from the one side of the target track | orbit in a virtual guide surface, and it sets an operation element so that a projection position may go to the other direction. An upper limit value is also set for the operation resistance force when moving, and "the upper limit value of the operation resistance force from one side of the target trajectory on the virtual guide surface to the other side" It is preferable that the value is set to a value larger than the “upper limit value of the operating resistance for moving the operating element in the direction of“. Thereby, the operating resistance force when moving the projection position from the other side of the target trajectory on the virtual guide surface to the one side can be made smaller than the operating resistance force when moving in the other direction. Only the operation resistance force when moving the projection position from the other side of the target trajectory to one side beyond the target trajectory can be increased, and the projection position can be moved with a smaller operating force in other directions. Can do.

FIG. 1 is a schematic view of a work assistance device 10 according to one embodiment of the present invention. The work assisting device 10 in this embodiment is a device that assists the work of applying an adhesive around the windshield W using the applicator 30.
The work assisting device 10 includes a moving mechanism 11 that supports the applicator 30 that is an object, and a controller 22 that controls the moving mechanism 11.
The moving mechanism 11 is fixed to the floor by a moving mechanism base 13. From the moving mechanism base 13 to the tip of the moving mechanism 11, the links 12a, 12b, and 12c and the joints 14a, 14b, and 14c that connect the adjacent links 12 in a swingable manner are connected. The joint 14a connects the moving mechanism base 13 and the link 12a. Actuators 16a, 16b, and 16c are installed in the joints 14a, 14b, and 14c, respectively. The joint group 14 is driven by the actuator group 16. Hereinafter, when the actuator group and the joint group are collectively referred to, the subscripts a, b, and c are omitted. By using the actuator group 16, the tip of the link 12 c can be moved to an arbitrary position within the movable range of the moving mechanism 11. Further, the direction in which the link 12c extends can be directed to an arbitrary direction. The joints 14a, 14b, and 14c are provided with position sensors 15a, 15b, and 15c, respectively. The position sensor group 15 is an encoder or the like. From the value output by the position sensor group 15 and the structure of the link group 12 of the moving mechanism 11, the coordinates of the reference point P in the absolute coordinate system can be obtained by geometric calculation.
An applicator 30 is supported on the link 12 c at the tip of the moving mechanism 11. An adhesive is discharged from the tip of the applicator 30. A reference point P is fixed to the tip of the applicator 30. A supply hose 34 for supplying an adhesive is connected to the applicator 30.
An operating element 18 is disposed on the link 12 c at the tip of the moving mechanism 11 via the force sensor 20 near the applicator 30. That is, the work assisting device 10 of the present embodiment also serves as a resistance applying mechanism in which the moving mechanism 11 that moves the applicator 30 (object) applies an operating resistance to the operation element 18. Therefore, the controller 22 is not only a moving mechanism controller for controlling the moving mechanism 11 but also an applying mechanism controller for controlling the resistance applying mechanism.
When the operator operates the operating element 18, the operating force is detected by the force sensor 20. The detected operating force is sent to the controller 22. The controller 22 controls the actuator group 16 of the moving mechanism 11 so as to move the applicator 30 in the direction of the operating force. The contents of the control will be described later with reference to FIG.

In the present embodiment, the windshield W that is an object to which the adhesive is to be applied is supported by the work support device 24 via the work rotation support shaft 26. The workpiece support device 24 rotates the windshield W around the rotation axis C at an angular velocity ω by a workpiece rotation support shaft 26. An application line L where an adhesive is to be applied is set around the windshield W.
In the present embodiment, the windshield W rotates. Accordingly, the coating line L set on the windshield W to which the adhesive is to be applied also rotates. The operator operates the operation element 18 so that the portion where the adhesive at the tip of the applicator 30 is discharged, that is, the reference point P, coincides with the rotating application line L. Since the windshield W to which the adhesive is to be applied rotates, the operator can apply the adhesive around the large windshield W without walking around the windshield W.
In this embodiment, the application line L corresponds to the target trajectory to be followed by the reference point P set on the application device 30. Hereinafter, the coating line L is referred to as a target trajectory L. It is important that the reference point P moves along the target trajectory L, and the target trajectory L does not need to be stationary with respect to the absolute coordinate system. Even when the target trajectory L moves relative to the absolute coordinate system, the reference point P only needs to move along the target trajectory L.

Next, the operation of the work auxiliary device 10 will be outlined. Details will be described later.
The controller 22 sets the virtual guide surface 40 on the same surface as the surface of the windshield W. The virtual guide surface 40 includes the target track L. Then, the outside of the target track L (the outside of the windshield W) is set as the first side 42 (corresponding to one side of the target track L on the virtual guide surface) within the plane of the virtual guide surface 40, and the target track The inner side of L is set as the second side 44 (corresponding to the other side of the target trajectory L on the virtual guide surface).
When the position (projection position) where the reference point P is projected onto the virtual guide surface 40 is on the second side 44 side of the target trajectory L, the controller 22 performs a small operation with respect to the operation force FI applied to the operator 18 by the operator. The moving mechanism 11 is controlled so that a resistance force is applied to the operation element 18. Further, when the projection position is on the first side 42 side of the target trajectory L, the moving mechanism 11 is set so that a large operation resistance force is applied to the operation element 18 with respect to the operation force FI applied by the operator to the operation element 18. Control. In other words, this is nothing but moving the moving mechanism 11 so that the operation resistance force is applied to the operation element 18 with respect to the operation force FI. In other words, the moving mechanism moves the object based on the resultant force of the operation force and the operation resistance force received by the operator.
When a small operating resistance force is applied to the operating element 18 with respect to the operating force FI applied by the operator to the operating element 18, the moving amount of the object supported by the moving mechanism 11 increases. On the other hand, when a large operating resistance force is applied to the operating element 18, the amount of movement of the object becomes small with respect to the same operating force FI. If the magnitudes of the operating force FI and the operating resistance force are the same, the object does not move.

For the sake of explanation, a straight line Px is assumed in the direction in which the target trajectory L extends from the reference point P fixed to the tip of the applicator 30. A straight line Py is assumed in a direction perpendicular to the straight line Px and facing the outside of the windshield in the plane of the windshield W from the reference point P. A straight line Sx extending from the connection point S between the operating element 18 and the force sensor 20 in parallel with the straight line Px is assumed. A straight line Sy extending in parallel with the straight line Py from the connection point S is assumed.
The direction from the first side 42 to the second side 44 is the negative direction of the straight line Py and at the same time the negative direction of the straight line Sy.

The operator applies an operating force FI to the operation element 18 in order to move the reference point P along the target trajectory L. At this time, the operator operates the operator 18 so that the operation force FI generates a force component FIx in the Px linear direction and a force component FIy in the straight Py direction.
As shown in FIG. 1, the work assistance device 10 is configured so that when the reference point P coincides with the target trajectory L (in this case, the position of the reference point P is the projection position), the first side of the target trajectory L The moving mechanism 11 is controlled such that a large operating resistance force FRy is applied to the operating element 18 in the direction from the side 42 toward the second side 44 (that is, the negative direction of the straight line Sy). The work assisting device 10 also controls the moving mechanism 11 such that a small operating resistance force FRx is applied to the operating element 18 with respect to the Px linear component FIx of the operating force FI.

If FIy is not larger than the operation resistance force FRy, the operator cannot move the operation element 18 in the positive direction of the straight line Sy. In other words, the operator applies an operation force FI that includes the force component FIy in the straight line Sy direction and the force component FIx in the straight line Sx direction to the operator 18, so A sense that the reference point P is pressed against a ruler or template that is present in particular.
At the same time, the operation resistance force FRx is applied to the operation force FIx in the direction of the straight line Px. The moving mechanism 11 moves the reference point P in the direction of the straight line Px (the direction of the target trajectory L) so that the resultant force of the operating force FIx and the operating resistance force FRx is constant.
As a result, the operator can move the reference point P in the direction of the straight line Px (direction in which the target trajectory L extends) without meandering.
In other words, the work assistance device 10 corresponds to moving the reference point P based on the resultant force of the operation force FI and the operation resistance force (FRx and FRy).

Next, the configuration of the work assisting apparatus 10 that realizes the functions outlined above will be described using the block diagram of FIG. The work auxiliary device 10 can be roughly divided into a moving mechanism 11 and a controller 22.
The moving mechanism 11 includes a supported applicator 30, an operating element 18, a force sensor 20 that detects a force applied by the operator to the operating element 18, and an actuator group that moves each link group 12 of the moving mechanism 11. 16 and a position sensor group 15 for detecting the position of the reference point P set at the tip of the applicator 30. Hereinafter, the “virtual guide surface” is simply referred to as “guide surface”.

  The controller 22 includes a target trajectory data storage unit 50, a reference point data storage unit 52, a mechanism unit data storage unit 58, and a guide surface data storage unit 56 as data storage modules. The calculation module includes a guide surface setting unit 54, a reference point position calculation unit 60, a reference point / guide surface relative position calculation unit 62, a reference point movement position calculation unit 66, and an actuator driver 68. Here, the storage module is a memory or a hard disk device built in the controller 22. Alternatively, a storage device installed outside the controller may be used. The calculation module may be realized by a computer built in the controller 22 and software for the computer, or may be realized by hardware for performing a dedicated calculation.

  The target trajectory data storage unit 50 stores data on the target trajectory L. The target trajectory L may be obtained in real time by calculation as follows. That is, the position of the target trajectory L at each time is determined from the shape of the windshield W, the arrangement of the target trajectory L on the windshield W, the support position of the windshield W with respect to the workpiece rotation support shaft 26 and the rotational angular velocity ω of the windshield W. It may be calculated and calculated in real time. In this case, the target trajectory data storage unit 50 stores data such as the shape of the windshield W for generating target data. The target trajectory L is calculated in real time from the stored data such as the shape of the windshield W, and the calculated target trajectory L data is temporarily stored in the target trajectory data storage unit 50.

The guide surface setting unit 54 sets a guide surface including the target track from the target track data stored in the target track data storage unit 50. At the same time, which side of the target track is set to the side where the large operating resistance force is set in the guide surface (the first side 42 side shown in FIG. 1) is set. The side opposite to the first side 42 is set to the side for setting a small operating resistance force (the second side 44 side shown in FIG. 1).
Here, for example, when the target track draws a curve, the guide surface is set to a surface formed by the curve. The first side 42 is set outside the curve of the target trajectory within the guide surface. The “curve” here includes a case where the target trajectory is bent. The second side 44 is set on the side opposite to the first side 42 with respect to the target trajectory.
Further, the first side 42 of the guide surface serves as a ruler for a work tool such as the applicator 30, so that it can be set so that the worker can easily work. For example, the first side 42 is set on the side opposite to the operator's position with respect to the target trajectory.
Data relating to the guide surface set by the guide surface setting unit 54 is stored in the guide surface data storage unit 56.

  The reference point data storage unit 52 stores data indicating where the reference point P is fixed on the applicator 30. The mechanism unit data storage unit 58 stores data of the geometrically connected structure of the link group 12 from the moving mechanism base 13 to the tip of the moving mechanism 11. Further, data on the position of the moving mechanism base 13 in the absolute coordinate system is also stored.

  The reference point position calculation unit 60 acquires a signal from the position sensor group 15 arranged in the joint group 14 of the moving mechanism 11, and stores the geometric structure of the moving mechanism 11 stored in the mechanism unit data storage unit 58. In addition, the support position of the applicator 30 attached to the tip of the moving mechanism 11 is obtained. Further, the position of the reference point P with respect to the support position of the applicator 30 is obtained from the data of the position of the reference point P set on the applicator 30 stored in the reference point data storage unit 52. In this way, the reference point position calculation unit 60 obtains the position of the reference point P in the absolute coordinate system.

  In the reference point / guide surface relative position calculation unit 62, the reference point P is calculated from the coordinate data of the guide surface 40 stored in the guide surface data storage unit 56 and the coordinates of the reference point P obtained by the reference point position calculation unit 60. Is calculated on the guide surface 40 (projection position). Furthermore, the relative position between the projection position and the target trajectory L is also calculated. That is, it is calculated whether the projection position is located on the first side or the second side on the guide surface.

The position of the reference point P obtained by the reference point / guide surface relative position calculation unit 62, its projection position, and the relative position of the target trajectory are input to the reference point movement position calculation unit 66.
The reference point movement position calculation unit 66 also receives an operation force FI applied to the operation element 18 detected by the force sensor 20.
The reference point movement position calculation unit 66 calculates a movement position where the reference point P should be positioned next by the operation force FI. The calculation formula at that time is based on the following impedance control law.
FI = [Mp] · ddp + [Cp] · dp + FR (1st formula)
Here, ddp represents the acceleration of the reference point P. dp represents the speed of the reference point P. [Mp] represents the virtual mass of the reference point P. However, [Mp] is a 3 × 3 matrix in which diagonal elements are scalar quantities whose magnitude is virtual mass, and other elements are zero. [Cp] represents a virtual viscosity coefficient with respect to the speed of the reference point P. Similarly, “Cp” is a 3 × 3 matrix in which diagonal elements are scalar quantities whose magnitude is the virtual viscosity coefficient, and other elements are zero. FR represents a virtual frictional force determined by at least one of the speed, position and operating force FI of the reference point P.
The first equation is a virtual equation of motion in a three-dimensional space, and FI, ddp, dp, FR are vector quantities having respective elements in the three-axis directions in a predetermined coordinate system. [Mp], [Cp], and FR are preset in the reference point movement position calculation unit 66. Note that the virtual frictional force FR is a variable amount that changes according to at least one of the speed, position, and operating force FI of the reference point P.
The first equation can be transformed into the following second equation.
FI−FR = [Mp] · ddp + [Cp] · dp (2nd formula)
Here, the left side (FI-FR) of the second formula will be described. In the first equation, the sign of the virtual friction force FR is set in the same direction as the sign of FI. This is because the virtual frictional force FR on the right side of the first expression means that the operating force FI on the left side of the first expression includes a force that resists the virtual frictional force FR. The “force against the virtual friction force FR” is a force opposite to the virtual friction force FR actually applied to the operation element. Therefore, the direction of each axis component of the virtual frictional force FR itself that is actually applied to the operating element is opposite to the direction of each axis component of the operating force FI. If the sign of the virtual frictional force FR is defined as the same direction as the actual direction of each axis component, the left side of the second equation is expressed as (FI + FR). Here, if the term [Cp] · dp of the virtual viscosity coefficient is sufficiently small, the reference point P is calculated so as to generate an acceleration ddp corresponding to the resultant force of the operation force FI and the virtual friction force FR. Hereinafter, using the definition of the virtual frictional force FR represented by the first equation, (FI-FR) represented on the left side of the second equation will be referred to as a resultant force of the operating force FI and the virtual frictional force FR. .

According to the first formula (or the second formula), the acceleration ddp of the reference point P is obtained with the operation force FI as an input. The moving position of the next reference point P is obtained by integrating the obtained acceleration ddp twice. If the virtual mass Mp is reduced here, the reference point P can be moved greatly with a small operating force FI.
Moreover, the reference point P can be moved small by setting the virtual frictional force FR large. In this embodiment, the virtual friction force FR corresponds to the operation resistance force FR applied to the operation element. Therefore, hereinafter, the virtual friction force FR may be referred to as an operation resistance force FR.

The virtual frictional force FR of the first formula (or the second formula) will be described. In order to simplify the description, the description will be made with reference to FIG. 3 limited to two dimensions. FIG. 3 is a view of the applicator 30, the force sensor 20, and the operation element 18 shown in FIG. 1 as viewed from above. That is, in FIG. 3, the paper surface becomes the guide surface 40 as it is. Since the target track L is on the paper surface of FIG. 3, the guide surface 40 includes the target track L. However, in FIG. 3, the first side 42 is set on the lower side of the target track L and the second side 44 is set on the upper side of the target track L.
Now, a local coordinate system xy fixed to the applicator 30 is assumed with the center of the force sensor as the origin. The x axis of the local coordinate system xy is set in the direction in which the target trajectory L extends, and the y axis is set in the direction of the first side 42 of the guide surface 40 shown in FIG. It is assumed that the first equation is also expressed by a vector with this local coordinate system xy as a reference. However, since it is limited to two dimensions, each vector is a two-element vector of x elements and y elements.
Since FIG. 3 is limited to two dimensions, the position of the reference point P is the position where the reference point P is projected onto the guide surface 40 as it is. FIG. 3 shows a state where the reference point P fixed to the applicator 30 is coincident with the target trajectory L. That is, the operator wants to move the reference point P in the x-axis direction (the direction of the target trajectory L) without meandering in the y-axis direction. Therefore, the operator applies the operation force FI to the operator 18 as shown in FIG. The operating force FI is applied to the operator 18 so as to have a component in the direction in which the reference point P is to be moved (positive direction of the x axis) and a component in the direction of the first side 42 of the target trajectory L (positive direction in the y axis). Added. The x-axis direction component of the operating force FI is represented as FIx, and the y-axis direction component is represented as FIy.
In the state of FIG. 3, the reference point P coincides with the target trajectory L. At this time, the virtual frictional force FR of the first equation (or the second equation) becomes a large value in the direction from the first side 42 to the second side 44 of the target trajectory L (the negative direction of the y axis). Set to This virtual frictional force is indicated by FRy in FIG. A small virtual friction force FRx is set for the operation force FIx. When the first equation is divided into an x-direction component and a y-direction component, the following equation is obtained.
FIx = Mp · ddpx + Cp · dpx + FRx (3rd formula)
FIy = Mp · ddpy + Cp · dpy + FRy (4th formula)
Here, ddpx represents the acceleration in the x-axis direction of the reference point P, and dpx represents the velocity in the x-axis direction. Similarly, ddpy represents the acceleration in the y-axis direction of the reference point P, and dpy represents the velocity in the y-axis direction.

Here, generally, the frictional force acts so as to prevent the movement of the object in the direction opposite to the movement direction when attempting to move the object. However, the frictional force does not act actively so as to move the object in the direction opposite to the moving direction. In order to reproduce this frictional force, FRy is set to the same value as the y-direction component FIy of the operating force within a range not exceeding the upper limit value frmax. Since FIy and FRy have the same magnitude, the acceleration ddpy in the y direction of the reference point P is zero according to the fourth equation (provided that the y-direction velocity dpy is zero as an initial value). Therefore, when the operator applies the operation force FI so that the operation force FI has a component in the positive direction of the y axis, the reference point P is further moved in the positive direction of the y axis when the reference point P coincides with the target trajectory L. Stops moving. That is, the operator can feel as if there is a virtual ruler along the target trajectory L on the first side 42 side of the target trajectory L, and the reference point P is pressed against the ruler.
From a general mechanics point of view, this means that even if an operator applies a force to an object within a range that does not exceed the coefficient of static friction, the object does not move, and has the same magnitude as the force applied to the object. It means receiving power from the object. The reaction force at this time corresponds to the operation resistance referred to in this embodiment. From the third equation, when the acceleration ddpy and the speed dpy at the reference point P are zero, the operation reaction force is the virtual friction force FRy.

On the other hand, a virtual friction force FRx smaller than the operation force FIx is set in the x-axis direction. Therefore, the acceleration ddp of the reference point P in the x-axis direction is expressed by the following expression obtained by modifying the third expression.
ddpx = (FIx−FRx−Cp · dpx) / Mp (Expression 5)
Assuming that the term Cp · dpx of the virtual viscosity coefficient is sufficiently small, the acceleration ddpx corresponding to the resultant force (FIx−FRx) of the operating force FIx and the virtual friction force FRx is calculated from the fifth equation. As described above, the sign of the virtual friction force FRx is set in the same direction as the operation force FIx, as opposed to the sign of the friction force FRx that is actually applied to the operation element, so that (FIx−FRx) is equal to the operation force FIx. It represents the resultant force of the virtual frictional force FRx.

The reference point movement position calculation unit 66 integrates the acceleration ddpx obtained by the fifth equation twice to obtain the movement position of the reference point P. The obtained movement position of the reference point P is sent to the actuator driver 68. The actuator driver 68 drives the actuator group 16 provided in the movement mechanism 11 so as to realize the movement position of the reference point P.
Thus, the operator can move the reference point P in the x-axis direction while feeling the operation resistance force (FRx + Cp · dpx) from the operation element 18. Note that when the speed dpx of the reference point P is small enough to be ignored, the operation resistance force is substantially equal to the friction force FRx.
As a result, the operator can move the reference point P along the target trajectory L while pressing the reference point P against a virtual ruler along the target trajectory L on the first side 42 side. By realizing a state in which the reference point P is pressed against a virtual ruler along the target trajectory L, movement along the target trajectory L can be assisted without meandering the reference point P.

When the position of the reference point P is located on the second side 44 side of the target trajectory L on the guide surface 40, small values are set as the virtual frictional forces FRx and FRy in both the x-axis and y-axis directions. When the reference point P is located on the second side 44 side of the target trajectory L in the guide surface, the operator can move the reference point P to an arbitrary place with a small operating force.
Although the above description is limited to two dimensions, the same is true even if it is expanded to three dimensions. In this case, “reference point P” is replaced with “projection position” in the above description. In this case, the worker includes the target track L, and the plane orthogonal to the guide surface 40 serves as a virtual wall. The operator can move the reference point P along the virtual wall by operating the operator so that the reference point P is pressed against the virtual wall against the first side 42 side. After moving the reference point P to the target trajectory L along the virtual wall, the operator may be operated so as to move the reference point P in the direction in which the target trajectory L extends. The operator can move the reference point P along the target trajectory L while using a virtual wall as a base for preventing the reference point P from fluctuating.

In this embodiment, the moving mechanism 11 corresponds to one aspect of the “moving mechanism” and “resistance force applying mechanism” in the claims. A combination of the position sensor group 15 attached to the moving mechanism 11 and the reference point position calculation unit 60 that calculates the position of the reference point P by processing the output of this sensor is one aspect of the “position sensor” in the claims. Equivalent to. The target trajectory data storage unit 50 in FIG. 2 corresponds to one aspect of “target trajectory storage means” in the claims. In FIG. 3, when the reference point P coincides with the target trajectory L, the virtual frictional force FRy of the fourth equation is set to the same magnitude as the operation force FIy. This is equivalent to one mode of giving a large operating resistance force from one side of the target track to the other side in the virtual guide surface. Furthermore, in the description of the above embodiment, when the position of the reference point P is located on the second side 44 side of the target trajectory L within the guide surface, the virtual frictional forces FRx and FRy are small in both the x-axis and y-axis directions. Setting the value corresponds to one aspect of “providing a small operation resistance force when the projection position is on the other side of the target trajectory” in the claims.
Further, the reference point movement position calculation unit 60 for calculating the first expression to the fourth expression corresponds to one aspect of “calculation means” in the claims. As shown in FIG. 3, when the reference point P coincides with the target trajectory L, the first lateral 42 of the target trajectory L (one side of the target trajectory) to the second lateral 44 ( Processing for setting the virtual frictional force FRy in the direction toward the other side of the target trajectory to a value larger than the virtual frictional force FRx in the direction along the target trajectory L (x-axis direction) (reference point moving position calculation unit 60 However, the calculation formula calculated by the calculation means includes at least a virtual friction force term that prevents the movement of the virtual object, and the projection position is one of the target trajectories in the guide surface. Equivalent to an example of setting the virtual friction force to a large value when it is on the side of the object and calculating the motion generated in the virtual object by setting the virtual friction force to a small value when it is on the other side of the target trajectory. To do.

In the above embodiment, an upper limit value is provided for the operating resistance force FRy (equal to the virtual frictional force) FRy from the first side 42 to the second side 44 of the target trajectory L on the virtual guide surface 40. Of the force FI, when the operating force component FIy directed from the other side of the target trajectory to one side is smaller than the upper limit value, the target trajectory L travels from the first side 42 to the second side. It is also preferable to set the manipulation resistance force FRy to the same magnitude as the manipulation force component FIy of the manipulation force FI from the second side 44 of the target trajectory L toward the first side 42.
As a result, when the operator moves the projection position from the second side 44 side of the target trajectory L to the first side 42 side, it is as if it is large on the first side 42 side with respect to the target trajectory L as a boundary. The operation resistance force FRy can be felt from the operation element 18 as if receiving a Coulomb friction force (static friction force). When the operation force FIy is less than the static friction force, the reference point P (projection position in the three-dimensional space) does not move further to the first side 42 side of the target trajectory L when it coincides with the target trajectory L.
On the other hand, when the worker applies a working force FIy exceeding the upper limit value in a direction from the second side 44 side of the target track L toward the first side 42 side, the operating force FIy exceeds the static friction force. The reference point P can be moved to the first side of the target trajectory L. This will be described later with reference to FIG.

  Next, a modified example of setting the guide surface in the embodiment will be described with reference to FIGS. In the following, for simplification of explanation, FIGS. 4 to 7 are simplified or omitted as follows for the auxiliary work apparatus 10 of FIG. 1 and the windshield or the like to be worked. First, the target trajectory L was limited to two dimensions. The force sensor 20 is directly fixed to the applicator 30 and the operation element 18 is fixed to the force sensor 20. The moving mechanism 11 that supports and moves the applicator 30 and the windshield W on which the target trajectory L is set are also not shown. In FIG. 1, it has been described that the windshield W rotates, but here the target track L is assumed to be fixed. The local coordinate system xy was set in the same manner as in FIG. Hereinafter, the frictional force FR is referred to as an operation resistance force FR. Further, since the operation resistance force directed from one side of the target trajectory L to the other side will be described below, the illustration of the component FRx in the x-axis direction of the operation resistance force FR is omitted.

First, the case where the data of the target trajectory L stored in the target trajectory data storage unit 50 shown in FIG. 2 and the actually desired target trajectory are shifted will be described with reference to FIG. An error often occurs in attaching the windshield W or assembling the moving mechanism 11. Therefore, an error often occurs between the stored target trajectory data and the actually desired target trajectory. In this embodiment, even in such a case, the reference point P can be easily followed with respect to the desired target trajectory without meandering.
4, the guide surface 40 is set to the same plane as the paper surface of FIG. The first side 42 of the target trajectory L is set to the lower side of the page of the target trajectory L in FIG. 4, and the second side 44 is set to the upper side of the page of FIG.

In this modification, an upper limit value frmax is provided for the operation resistance force FRy with respect to the force FIy applied in a direction orthogonal to the target trajectory L.
Now, according to the target trajectory data stored in the target trajectory data storage unit 50, the target trajectory L shown in FIG. 4 is obtained, but the actually desired target trajectory is the target trajectory L2 shown in FIG. . Note that the target trajectory L2 that is actually desirable is recognized by the operator visually viewing the actual coating line L on site. Therefore, the operator needs to bring the reference point P as close as possible to the actual coating line L2 (desired target trajectory L2). When the force FIy applied by the operator to the operation element 18 in the direction orthogonal to the target trajectory L is smaller than the upper limit value frmax of the operation resistance force FRy, the reference point P is indicated by a broken line Pa in FIG. It becomes the position. At this time, the applicator is at a position indicated by a broken line 30a. Note that frmax shown in FIG. 5 corresponds to FRy.
The operator applies a force exceeding the upper limit value frmax of the operation resistance force FRy to the operation element 18 in the positive direction of the y-axis. The operating force at this time is FI + dFI. The component in the y-axis direction of “FI + dFI” is FIy + dFIy. Here, FIy is a force having the same magnitude as the upper limit value frmax of the operating resistance force, and is a force that dFIy exceeds frmax. At this time, the fourth equation is FIy + dFIy = Mp · ddpy + Cp · dpy + frmax (Equation 6)
It becomes. Since FIy and frmax are equal, an acceleration in the y-axis direction represented by the following equation can be generated at the reference point P.
ddpy = (dFIy−Cp · dpy) / Mp (Expression 7)
Therefore, by providing an upper limit value for the operation resistance force FRy, if the operator applies an operation force exceeding the upper limit value, the reference point P is moved from the target trajectory L stored in the target trajectory data storage unit to the first side 42. The reference point P can be moved to the side. The operator can make the reference point P coincide with the actual target trajectory L2 by adjusting the operating force exceeding the upper limit value. In FIG. 4, the applicator 30b in a state where the reference point P coincides with the point Pb on the actual target trajectory L2 is drawn by a solid line by the operation force FI + dFI applied by the operator.
By providing the upper limit value for the operation resistance in this way, even if the actual target trajectory L2 deviates from the target trajectory L stored in the target trajectory data storage unit 50 toward the first side 42, the work can be performed. The person can make the reference point P coincide with the actual target trajectory L2.
Although it is necessary to increase or decrease the magnitude of the operating force FI + dFI, it is much more difficult than the case where there is no source of force for stabilizing the reference point P in the direction crossing the target trajectory L as in the prior art. It becomes easy to move the reference point P along the target trajectory L. The above case can be compared to tracing a line with a pen using a resilient ruler. When the line to be traced is hidden inside the ruler, the ruler can be bent by increasing the force of applying the pen to the ruler. For the same reason, also in this modification, the reference point P can be easily moved along the desired target trajectory even when there is a deviation between the target trajectory on the data and the desired target trajectory L.
At this time, the operator applies an operation force larger than the operation resistance force in the direction of the desired target trajectory L2. The reference point P can be advanced along the desired target trajectory L2 while feeling an operation resistance force of a certain size (frmax in this example). The operator can feel an operation resistance of a certain level (in this example, frmax) in a direction intersecting the desired target trajectory L2. By using this operation resistance force as the basis of the operation force, the reference point P can be stabilized with respect to the direction intersecting the target trajectory. This prevents the reference point P from meandering when the reference point P is moved along the desired target trajectory L2. A device that assists the operation of advancing the reference point P without meandering along the desired target trajectory L2 can be realized.

In FIG. 4, the target trajectory L stored in the target trajectory data storage device 50 (see FIG. 2) is a desirable target trajectory that is matched when the reference point P is actually moved. In that case, in the modification shown in FIG. 4, when the desired target trajectory L2 is shifted to the first side 42 side of the target trajectory L, out of the operating force FI from the second side 44 of the target trajectory to the first side. By adjusting the operating force in the direction toward the direction 42, the reference point P could be matched with the desired target trajectory L2. There is a possibility that the desired target trajectory L2 is shifted from the target trajectory L stored in the target data storage unit 50 to the second side 44 side. In that case, only a small resistance acts on the operation element. Therefore, there is a possibility that the reference point P meanders with respect to the desired target trajectory L2. Therefore, as shown in FIG. 5, temporary target trajectories La and Lb, which are separated from each other by a tolerance dH of the reference point P on the guide surface 40 with respect to the desired target trajectory L2, are set as target trajectory data. This is stored in the storage unit 50. Then, the first side 42a is set on the opposite side of the desired trajectory L2 with respect to the target trajectory La on the data. Similarly, the first side 42b is set on the opposite side of the desired trajectory L2 with respect to the target trajectory Lb on the data. In FIG. 5, the sides on which oblique lines are drawn with respect to the target trajectories La and Lb on the data are the first lateral sides 42a and 42b.
When the desired target trajectory L2 is shifted to the first side 42a of the target trajectory La on the data, the operator moves the reference point P in the direction of the first side 42a of the target trajectory La on the data "frmax". The above operation force FI is applied to the operation element 18. Then, the reference point P can be moved to the first side 42a side of the target trajectory La on the data by the operating force exceeding “frmax”. On the other hand, when the desired target trajectory L2 is shifted to the first side 42b of the target trajectory Lb in the data, the operator sets the reference point P to “frmax” in the direction of the first side 42b of the target trajectory Lb. The above operation force FI is applied to the operation element 18. Then, the reference point P can be moved to the first side 42b side of the target trajectory Lb on the data by the operation force exceeding “frmax”.

  In this modification, the target trajectories La and Lb on the data are set at positions shifted by the positional deviation error dH of the reference point P on both sides of the desired target trajectory L2. The operator applies an operating force to the operator in the direction of the target track along with the force pressing the temporary target track La or Lb. The reference point P is moved in the direction of the desired target trajectory L2 without meandering in the direction crossing the desired target trajectory L2, while keeping the reference point P within the allowable position error with respect to the desired target trajectory L2. Can do. Furthermore, in this modification, even if the desired target trajectory L2 is shifted to any side of the guide surface 40, a certain amount of operation force is applied to the temporary target trajectories La and Lb to a certain extent. The reference point P can be advanced along the desired target trajectory L2 while feeling an operation resistance force having a magnitude (frmax in this example). The operator can feel an operation resistance of a certain level (in this example, frmax) in a direction intersecting the desired target trajectory L2. By using this operation resistance force as the basis of the operation force, the reference point P can be stabilized with respect to the direction intersecting the target trajectory. As a result, it is possible to realize an apparatus that assists the work of advancing the reference point P without causing the reference point P to meander within the allowable error range of the desired target trajectory L2.

Next, a case where the target trajectory includes a bent portion or a case where the target trajectory draws a curve will be described with reference to FIG. The target trajectory L shown in FIG. 6 includes a bent portion R and a curved portion T. The guide surface 40 is set to coincide with the paper surface. In the present specification, the “bent portion” is also included in the concept of the “curved portion” as an extreme form of the curved portion.
In FIG. 6, the guide surface 40 is set on the same surface as the paper surface.
In the vicinity of the bent portion R, the first side 42c of the target trajectory L is set to the side where the angle of the bent portion S of the target trajectory L is large (the side where the oblique line is drawn with respect to the target trajectory L in FIG. 6). Yes. Since the “bent portion” is an extreme form of the curved portion, “the side with the larger angle of the bent portion S” is synonymous with setting “outside the curve of the curved portion”. The second side 44c of the target trajectory L is set inside the curve of the target trajectory L.

In the vicinity of the curve T, the first side 42d of the target trajectory L is set to the outside of the curve of the target trajectory L (the side on which the diagonal line is drawn with respect to the target trajectory L in FIG. 6). The second side 44d of the target trajectory L is set inside the curve. The outside of the curve means the side opposite to the side where the center of the radius of curvature for the curve is located.
As shown in FIG. 6 and as described above, in this modification, the setting of the first side and the second side of the target trajectory L on the guide surface 40 is changed before and after the point S on the target trajectory L. .

By setting the first side 42c, 42d and the second side 44c, the target trajectory L having a bent portion or a curve is not meandered in the direction intersecting the target trajectory L (without wobbling). ) The reference point P can be easily moved along the target trajectory L. This is due to the following reason.
When a ruler having the same shape as the bend line is applied to the bend line drawn on the paper and the bend line is traced with a pen, it is easier to trace the ruler to the outside (the side with the larger angle) of the bend line. Similarly, when a ruler having the same shape as a curve is applied to a curve drawn on paper and the curve is traced with a pen, it is easier to trace the ruler outside the curve. The operator moves along the ruler while pressing the pen against the ruler. At this time, if you trace a line bent by applying a ruler to the inside of the bent line (the side with the smaller angle) with respect to the bent line, the ruler will be bent at an acute angle at the bent part. As a result, the pen may lose its strength and the pen may be greatly disengaged from the ruler. When a ruler is applied to the large angle side of the bent portion, the ruler bends at an acute angle at the bent portion. The pen is temporarily stopped at the bent portion of the ruler at an acute angle. Then, the pen can be moved in the direction of the bent point. At this time, the force that presses the pen against the ruler is not so strong that the pen does not deviate greatly from the ruler.
The setting of the first side surfaces 42c and 42d shown in FIG. 6 serves as a ruler for the operation of tracing the curve drawn on the paper with a pen. For the same reason as the ruler for tracing a curve drawn on paper with the pen, the first side 42c and 42d shown in FIG. Without) the reference point P can be easily moved along the target trajectory L.

The operation of the first side surfaces 42c and 42d shown in FIG. 6 will be specifically described.
From the position where the reference position P is indicated by Pc in FIG. 6, the operator moves the operating element 18 so that the operating force FI is pressed toward the first side 42c of the target trajectory L and directed in the x-axis direction. . The operation resistance force FRy acts on the component FIy in the y-axis direction of the operation force FI and balances. The reference point P moves along the target trajectory L in the x-axis direction by the component FIx in the direction along the target trajectory L of the operating force FI. (As described above, the x-axis component FRx is omitted from the operation resistance force FR).
Since the first side 42c is set to have a larger angle at the bent portion R of the target trajectory L, when the reference point P reaches the bent portion R of the target trajectory L, the reference point P is moved so far. A large operating resistance force is also generated for the component FIx of the operating force FI that has been acting. As a result, the reference point P temporarily stops at the bent portion R of the target trajectory L with the operation force FI thus far. Therefore, the operator again adjusts the direction of the operation force FI so that the component of the operation force is generated in the direction along the target track L. If, as a result of the adjustment, an operation force component in a direction along the target trajectory L after bending occurs, the reference point P resumes moving along the target trajectory L after bending. When the target trajectory L includes the bent portion R in this way, the first side 42c is set to the side with the larger angle of the bent portion R of the target trajectory L (the second side 44c is bent of the target trajectory L). By setting the angle of the portion R to be smaller, the reference point P can be smoothly moved along the target trajectory L without greatly shifting from the target trajectory L even at the bent portion R.
Next, the case where the reference point P reaches the curve T of the target trajectory L like the position of Pd shown in FIG. 6 will be described. In the vicinity of the curve T, the first side 42d of the target track L is set outside the curve T with respect to the target track L. Therefore, as the reference point P advances along the curve T, a large operating resistance force FR is generated against the FIx component of the operating force FI that has acted to advance the reference point P. The reference point Pd is forcibly curved along the curve T by the operation resistance force FR directed from the outside to the inside of the curve T. The operator can easily advance the reference point P along the target trajectory L simply by directing the direction of the operating force FI in the direction of the target trajectory preceding the reference point P of the curve T.

Next, the case where two virtual guide surfaces that intersect with the target trajectory are set will be described with reference to FIG. 7A and 7B show a coordinate system for explanation. FIG. 7A shows a view of the guide plane and the XZ plane of the target trajectory L. FIG. FIG. 7B shows a view of the guide surface and the YZ plane of the target trajectory L when FIG. 7A is viewed from the arrow B direction.
The target trajectory L coincides with the X axis in FIG. One guide surface 40e is set to the XZ plane. The first lateral side 42e of the guide surface 40e is set on the negative side of the z axis on the guide surface 40e. The other guide surface 40f is set to the XY plane. The first side 42f of the guide surface 40f is set on the positive side of the y-axis on the guide surface 40f. Since the target trajectory L coincides with the x-axis and the guide surface 40e is set to the XZ plane, the guide surface 40e is a surface including the target trajectory L. Similarly, since the guide surface 40f is set to the XY plane, the guide surface 40f is also a surface including the target trajectory L.

In order to move the reference point P along the target trajectory L, the operator applies an operating force FI to the operator 18. The force components in the directions of the three axes XYZ of the operating force FI are FIx, FIy, and FIz. The reference point P can be moved in the X-axis direction by the X-direction component FIx.
As shown in FIG. 7A, an operation resistance force FRz in the direction from the first side 42e of the guide surface 40e toward the second side 44e acts on FIz. The large operation resistance force FRz makes it difficult for the operator to move the reference point P in the negative z-axis direction.
As shown in FIG. 7B, the operation resistance force FRy in the direction from the first side 42f of the guide surface 40f to the second side 44f acts on FIy. The large operation resistance force FRy makes it difficult for the operator to move the reference point P in the positive direction of the y-axis.
The operation resistance force is a resultant force FRyz of FRz acting on the guide surface 40e and FRy acting on the guide surface 40f. This resultant force FRyz acts against the resultant force FIyz in the yz plane of the operating force FI. The operator can make the reference point P coincide with the target trajectory L in the yz plane only by turning the direction of the operating force FIyz in the yz plane so as to be within the range of the angle K formed by the guide surfaces 40e and 40f. .
The operation resistance forces FRz and FRy are calculated on each of the two guide surfaces 40e and 40f intersecting with the target trajectory L, and the resistance force application mechanism applies the resultant force FRyz to the operator. As a result, it is possible to apply an operation resistance force that opposes the resultant force FIyz of the operation force component in the direction intersecting the target trajectory L of the operation force FI applied by the operator to the operator. The worker simply adjusts the direction of the resultant force FIyz of the operation force component in the direction intersecting the target trajectory L so as to be within the range of the angle K formed by the two guide surfaces 40e and 40f, and the work assisting device can The operation of moving the point P along the target trajectory L without meandering can be assisted.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.

For example, when the operation resistance force has an upper limit value and the projection position is on one side of the target trajectory on the virtual guide surface, the operation resistance is directed from one side of the target trajectory to the other side. It is preferable that the upper limit value of the force is set to be larger than the upper limit value of the operating resistance force other than “when the projection position is on one side of the target trajectory on the virtual guide surface”. When the upper limit value of the operation force in each direction does not exceed the upper limit value, it is preferable to set the operation resistance force in each direction to the same magnitude as the operation force.
According to this, when the projection position is on one side of the target trajectory on the virtual guide surface, only the upper limit value of the operation resistance force from one side of the target trajectory toward the other side is set large. . That is, when the projection position is on one side of the target trajectory on the virtual guide surface, a large operating force is required in the direction further away from the target trajectory. On the other hand, a small operation resistance force is set for the operation force that attempts to move the projection position in other directions. By applying an operating force that exceeds a small operating resistance force, move the projected position further away from the target trajectory with a small operating force when the projected position is on one side of the target trajectory on the virtual guide surface. be able to.
When the operating force is smaller than the upper limit value of the operating resistance force, the operating resistance force is set to the same magnitude as the operating force. As a result, even when the operation force is weakened, the operation resistance force does not become larger than the operation force, and it is possible to prevent the projection position from moving in the direction opposite to the direction of the operation force.

For example, in the above-described embodiment, the reference point movement position calculation unit 66 calculates the movement position of the reference point P as a result of applying the operation resistance force. That is, the controller 22 controls the moving mechanism 11 using the moving position of the reference point P as a command value. In addition to this, the controller 22 can also use the force to be generated at the reference point P as an instruction value of the track mechanism 11 in consideration of the operation resistance force. In this case, the actual characteristics of the hardware of the moving mechanism 11 are grasped in advance. In the following description, the equation is limited to one dimension. The actual hardware characteristics are expressed by the following equation.
FI + FA = Ma · ddpa + Ca · dp + FB (Eighth Formula)
Here, FI is a value obtained by converting the operating force applied by the operator to the operator to the position of the reference point P, and FA is a force that the actuator of the moving mechanism should output at the reference point P. Ma, Ca, and FB are the actual mass, viscosity, and Coulomb friction force of the hardware at the reference point P of the moving mechanism 11. ddp represents the acceleration of the reference point P. dp represents the speed of the reference point P. A desirable dynamic characteristic to be realized at the reference point P is expressed by the above-described first equation.
FI = Mp · ddp + Cp · dp + FR (1st formula)
Here, FI + FA− (Ma / Mp) · FI = Ma · ddpa + Ca · dp + FB from (Equation 8) − (Ma / Mp) · (Equation 1)
− (Ma / Mp) · (Mp · ddp + Cp · dp + FR) (Equation 9)
Is obtained. From Equation 9, the force FA that the actuator should output in order to obtain the desired dynamic characteristics is
FA = {Ca− (Ma / Mp) · Cp} dp + FB
-{1- (Ma / Mp)}. FI- (Ma / Mp) .FR (Expression 10)
It becomes.
The reference point movement position calculation unit 66 sets the operation resistance force FR corresponding to the position of the reference point P in the tenth equation, and calculates the tenth equation by detecting the operation force FI from the force sensor 20. In order to realize the obtained force FA (the force that the moving mechanism 11 should generate at the reference point P), the force FA is converted into the force that each actuator of the moving mechanism 11 should output, and the force command value to each actuator. Is output.
As described above, the work assistance device 10 can also set the force FA to be generated at the reference point P as the control target value after applying the operation resistance force FR.

  Further, in the embodiment, the mode in which the operating element 18 is installed in the moving mechanism 11 is illustrated, but the operating element 18 is not fixed to the moving mechanism 11 and gives an operation resistance force to another mechanism, that is, the operating element. It is also preferable to provide a resistance applying mechanism that separates from the moving mechanism 11.

In the above embodiment, the reference point and the target trajectory do not necessarily need to be the tip of the work implement (the place where the work is performed) and the application line or welding line that is the work target. The reference point and target trajectory are offset with respect to the tip of the work tool and the application line or welding line that is the work target, so that the location where the work tool is operated matches the application line or welding line that is the work object. You may set to the position which provided. If the object held by the moving mechanism is a workpiece, a reference point set on the workpiece and a trajectory that the reference point should follow should be set as the target trajectory.
The moving mechanism may have any structure as long as it has a degree of freedom equal to or greater than the degree of freedom when positioning the object. A multi-link structure as shown in FIG. 1 or a structure such as a gantry crane may be used.

  The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

It is the schematic of the work assistance apparatus 10 of the Example which concerns on this invention. 1 is a block diagram of a work assistance device 10. FIG. It is a figure explaining the positional relationship of a target track, a guide surface, and the reference point P, and the effect of a guide surface (1). It is a figure explaining the positional relationship of a target track | orbit, a guidance surface, and the reference point P, and the effect of a guidance surface (2). It is a figure explaining the positional relationship of a target track | orbit, a guide surface, and the reference point P, and the effect of a guide surface (3). It is a figure explaining the positional relationship of a target track | orbit, a guide surface, and the reference point P, and the effect of a guide surface (4). FIG. 7A is a diagram illustrating the positional relationship of the target trajectory, the guide surface, and the reference point P in the XZ plane. FIG. 7B is a diagram showing the positional relationship of the target trajectory, the guide surface, and the reference point P in the YZ plane. It is a schematic diagram explaining the operation resistance force which should be generated on each virtual guide surface at the time of setting two virtual guide surfaces.

Explanation of symbols

10: Work assistance device 11: Movement mechanisms 12a, 12b, 12c: Link 13: Movement mechanism bases 14a, 14b, 14c: Joints 15a, 15b, 15c: Position sensors 16a, 16b, 16c: Actuator 18: Operator 20: Force Sensor 22: Controller 24: Work support device 26: Work rotation support shaft 30: Application tool (object)
40, 40e, 40f: guide surfaces 42, 42a, 42b, 42c, 42d, 42e, 42f: first surface 44, 44a, 44b, 44c, 44d, 44e, 44f: second surface 50: target trajectory data storage unit 52 : Reference point data storage unit 54: Guide surface setting unit 56: Guide surface data storage unit 58: Mechanism unit data storage unit 60: Reference point position calculation unit 62: Reference point / guide surface relative position calculation unit 66: Reference point movement Force calculation unit 68: Actuator driver W: Windshield L: Application line (target trajectory)
P: Reference point

Claims (8)

It is a device that assists the operator in moving the reference point fixed to the object along the target trajectory,
A moving mechanism that can support the object and moves the object using power;
A position sensor for detecting the position of the reference point;
Target trajectory storage means for storing the target trajectory;
An operator operated by an operator to indicate the movement position of the reference point;
A resistance applying mechanism for applying an operating resistance to the operator;
An application mechanism controller for controlling the resistance application mechanism;
It has a moving mechanism controller that controls the moving mechanism,
The assigning mechanism controller sets a virtual guide surface including the target trajectory, and when the target trajectory coincides with a position (referred to as a projection position) obtained by projecting the position of the reference point detected by the position sensor onto the virtual guide surface. A large operation resistance force from one side of the target trajectory on the virtual guide surface to the other side is applied to the operator by the resistance applying mechanism, and a small operation is performed when the projection position is on the other side of the target trajectory. Giving resistance,
The movement mechanism controller moves an object based on a resultant force of an operation force and an operation resistance force received by the operation element.   The applying mechanism controller applies a large frictional force to the resistance applying mechanism when the projection position is on one side of the target trajectory on the virtual guide surface, and is small to the resistance applying mechanism when on the other side of the target trajectory. The work assisting device according to claim 1, wherein a frictional force is applied. The moving mechanism also serves as a resistance applying mechanism,
The object and the operator are supported by one rigid body on the moving mechanism,
The work assisting device according to claim 1, wherein a force sensor is interposed between the rigid body and the operation element.   The movement mechanism controller has calculation means for calculating a motion that occurs when the force detected by the force sensor is applied to the virtual object, and controls the movement mechanism so as to realize the calculated movement at the reference point. The work auxiliary device according to any one of claims 1 to 3, wherein   The calculation formula calculated by the calculation means includes at least a virtual friction force term that prevents the movement of the virtual object. When the projection position is on one side of the target trajectory in the guide surface, the virtual friction force is set to a large value. The work assisting device according to claim 4, wherein when it is on the other side of the target trajectory, the virtual frictional force is set to a small value to calculate the motion generated in the virtual object.   The work assisting device according to any one of claims 1 to 5, wherein an upper limit value is provided for the operation resistance force from one side of the target track to the other side of the target track on the virtual guide surface. .   The grant mechanism controller calculates an operation resistance force on each of the two virtual guide surfaces that intersect in the target trajectory, and causes the resultant force to be imparted to the operator by the resistance force grant mechanism. The work auxiliary device according to claim 1.   The resistance force applying mechanism sets one side of the target track on the virtual guide surface outside the curve when the target track includes a curve. Work auxiliary equipment.

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