KR102341829B1 - Control unit for automatic operation of the engine-driven lawn mower and automatic driving method thereof - Google Patents

Abstract

A control apparatus for automatic operation of an engine-driven lawn mower according to the present invention includes: an integrated controller configured to calculate left and right wheel speeds of the lawn mower according to input target speeds and target attitude angles; a motor control unit outputting a left motor drive signal corresponding to a left lever position mapped to the left wheel speed and a right motor driving signal corresponding to a right lever position mapped to the right wheel speed; a motor unit including a left motor generating a left rotational force according to the left motor driving signal and a right motor generating a right rotational force according to the right motor driving signal; a gear unit including a left gear that converts the left rotational force into a reciprocating linear motion and transmits it to a left lever, and a right gear that converts the right rotational force into a reciprocating linear motion and transmits it to the right lever; and an engine that provides driving power for automatically driving the lawn mower according to the reciprocating linear motion of the left lever and the right lever.

Description

BACKGROUND ART A control unit for automatic operation of the engine-driven lawn mower and automatic driving method thereof

The present invention relates to an engine-driven lawn mower, and to an automatic operation control technology thereof.

In the prior art document with the application number '10-2004-0013116', the left and right independent continuously variable transmission devices are operated, and the left and right steering levers are operated in the forward/rearward direction to operate these continuously variable transmission devices separately. Disclosed is a passenger lawn mower capable of turning on the spot by moving it forward or backward or reversely rotating it in one direction.

This prior art document is a mechanical system for manual lever operation, and manual lever operation in a simple and repeated weeding operation is inconvenient and inefficient. Accordingly, there is an urgent need to develop a lawn mower capable of automatic operation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a control device and a control method for automatic operation of an engine-driven lawn mower for resolving the inconvenience and inefficiency of manual lever operation.

A control method for automatic operation of an engine-driven lawnmower according to the present invention includes: calculating, by an integrated controller, left and right wheel speeds of the lawnmower from input target speeds and target attitude angles; outputting, by the motor controller, a left motor driving signal corresponding to a left lever position mapped to the left wheel speed and a right motor driving signal corresponding to a right lever position mapped to the right wheel speed; generating, by the left motor, a left rotational force according to the left motor driving signal, and by the right motor, generating a right rotational force according to the right motor driving signal; converting, by the left gear, the left rotational force into a reciprocating linear motion and transmitting it to the left lever, and the right gear converting the right rotational force into a reciprocating linear motion and transmitting it to the right lever; and performing, by the lawn mower, automatic operation according to the reciprocating linear motion of the left lever and the right lever.

An engine-driven lawn mower of the present invention includes: an integrated control unit that calculates left and right wheel speeds of the lawn mower according to input target speed and target attitude angle; a motor control unit outputting a left motor drive signal corresponding to a left lever position mapped to the left wheel speed and a right motor driving signal corresponding to a right lever position mapped to the right wheel speed; a motor unit including a left motor generating a left rotational force according to the left motor driving signal and a right motor generating a right rotational force according to the right motor driving signal; a gear unit including a left gear that converts the left rotational force into a reciprocating linear motion and transmits it to a left lever, and a right gear that converts the right rotational force into a reciprocating linear motion and transmits it to the right lever; and an engine that provides driving power for automatically driving the lawn mower according to the reciprocating linear motion of the left lever and the right lever.

According to the present invention, since the automatic driving and automatic steering control of the engine-driven lawn mower operated by the lever is possible, the weeding operation can be performed by automatic operation.

In addition, the user's convenience is high by performing the weeding operation by automatic operation in a work space that requires repeated operations.

In addition, it is possible to increase efficiency by configuring an automatic operation and automation system of various mechanical devices operated by levers.

1 is a perspective view illustrating an external appearance of an engine-driven lawn mower according to an embodiment of the present invention;
Figure 2 is an enlarged view of an enlarged portion A of Figure 1;
Fig. 3 is a block diagram of a control device for automatic operation of the engine-driven lawn mower shown in Figs. 1 and 2;
FIG. 4 is a view for explaining a target speed and a target steering angle input to the subtractor shown in FIG. 3 ;
FIG. 5 is a view for explaining a method of calculating a left and right wheel speed performed by the integrated control unit shown in FIG. 3;
6 is a flowchart illustrating a control method for automatic operation of an engine-driven lawn mower according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention pertains can easily implement them. However, the present invention may be embodied in several different forms and is not limited to the embodiments described herein. And in order to clearly explain the present invention in the drawings, parts irrelevant to the description are omitted, and similar reference numerals are attached to similar parts throughout the specification.

1 is a perspective view illustrating an external phenomenon of an engine-driven lawn mower according to an embodiment of the present invention, FIG. 2 is an enlarged view of part A of FIG. 1 , and FIG. It is a block diagram of a control device for automatic operation of an engine-driven lawn mower, and FIG. 4 is a view for explaining a target speed and a target steering angle input to the subtractor shown in FIG. 3 .

First, referring to FIG. 3 , a control device 100 for automatic operation of an engine-driven lawn mower (hereinafter referred to as a 'lawn mower') according to an embodiment of the present invention (hereinafter referred to as a 'control device') is mounted on the engine-driven lawn mower shown in FIG. 1 .

The control device 100 automatically operates the lever 210 and drives the engine 220 according to the automatic operation of the lever 210 to control automatic operation (automatic driving and automatic steering) of the lawn mower.

To this end, the control device 100 includes an adder/subtractor 110 , an integrated controller (Mower Lever Integrated Controller) 120 , a motor controller 130 , a motor unit 140 , a gear unit 150 , and a sensor. It includes a unit 160 and an error calculation unit 170 .

Here, among the components in the control device 100 , the remaining components 110 , 120 , 130 , 160 and 170 , except for the motor unit 140 and the gear unit 150 , are not shown in FIGS. 1 and 2 , and the rest The configurations are assumed to be mounted inside a housing that forms the exterior of the engine driven lawn mower. Of course, depending on the design, the motor unit 140 and the gear unit 150 may also be mounted inside the housing.

Adder and Subtractor (110)

The adder/subtractor 110 bypasses (Target Mower Speed) (v _t ) and a target attitude angle (or target steering angle) _{initially input from an input unit (not shown) (Target Mower Heading Angle) (θ t} ) bypass) and input to the integrated control unit 120 .

In addition, the addition/subtractor 110 is configured to calculate _{a speed error v error for the actual speed v m} of the lawn mower corresponding to the _{target speed v t} and a speed error v _{error of} the lawn mower corresponding to the target attitude angle θ _{t .} The attitude angle error θ _error with respect to the actual steering angle θ _m is fed back from the error calculator 170 , and the velocity error v _error and the attitude angle error θ _{error are} calculated as the target speed v _t and the target attitude. The error between the actual speed (v _m ) and the actual attitude angle (θ _m ) is compensated for by adding or subtracting each to the angle (θ _{t ).}

The target speed (v _t ) and target attitude angle (θ _t ) are pre-calculated and set values. For the pre-calculation of the target speed (v _t ) and target attitude angle (θ _t ), the engine-driven lawn mower is separately of a sensor (camera, ultrasonic or infrared sensor) (not shown) and a separate processor unit (not shown) may be further provided.

The target speed (v _t ) and the target attitude angle (θ _t ) are, for example, as shown in FIG. 4 , a space 42, working space), the lawn mower 10 rotates in place at a fixed position inside and outside the working space, and after recognizing the landmark through various sensors provided therein, the processor unit sets the landmark According to the result of recognizing (40), the work space is partitioned into grid intervals, the optimal driving path (zig-zag, vortex direction) is calculated from the partitioned grid spacing, and the partitioned grid from the calculated optimal driving path. The target velocity (v _t ) and the target attitude angle (θ _t ) can be calculated for each interval.

Integrated control unit 120

Referring back to FIG. 3 , the integrated control unit 120 controls the left wheel angular velocity ω _{L according to the target velocity v t} and the target attitude angle θ _t input from the adder/subtractor 110 . Left Wheel angular speed) and the right wheel angular speed (ω _R , Right Wheel angular speed) is calculated and transmitted to the motor control unit 130 .

[Calculation of left and right wheel speed]

FIG. 5 is a diagram for explaining a method of calculating a left and right wheel speed performed by the integrated control unit shown in FIG. 3 .

Referring to FIG. 5 , the left and right wheel speed calculation is performed by calculating the turning radius of a differential steering system model composed of a drive wheel and a caster wheel to determine the left and right wheel speeds corresponding to the target speed and the target attitude angle. can be saved That is, the calculated turning radius is expressed as an equation for the left and right wheel speeds, and the left and right wheel speeds can be obtained by arranging them.

Calculation of left and right wheel speed is as follows.

The overall speed v of the lawn mower may be calculated as the angular velocity of the left and right wheels as shown in Equation 1 below.

where v _R is the right wheel speed, v _L is the left wheel speed and r is the tire radius.

If the heading angle of the lawn mower is known, the turning radius R can be obtained as in Equation 2 below.

,

는 선회 각속도(요레이트)이고, 선회 각속도는 잔디 깎기 기계의 좌우 휠 트레드(도 5의 t, 횡방향 길이)에 대한 휠 속도 차이로 계산되며, 아래의 수학식 3으로 나타낼 수 있다.here,

is a turning angular velocity (yaw rate), and the turning angular velocity is calculated as the wheel speed difference with respect to the left and right wheel treads (t, lateral length in FIG. 5) of the lawn mower, and can be expressed by Equation 3 below.

Using the above equations, the turning radius can be expressed as an equation for the left and right wheel speed, as shown in Equation 4 below.

By substituting the speed expression of Equation 1 into the turning radius expression organized by Equation 4 above, each left and right wheel speed can be organized by Equation 5 below.

motor control unit 130

The motor control unit 130 refers to a lookup table indicating the relationship between the left and right wheel speeds and the left and right lever positions, and the left lever position mapped to _{the left wheel speed ω L input from the integrated control unit 120 (} A left motor drive signal (L _{L ) corresponding to Left Lever Position and a right motor drive signal (L R} ) corresponding to the right lever position mapped to the right wheel speed (ω _R ) are generated. do.

The right motor driving signal L _R represents a rotor position value (rotor angle value) of the right motor 142 included in the motor unit 140 , and the left motor driving signal L _L is the motor unit 140 . It represents the rotor position value (rotor angle value) of the left motor 144 included in .

The lookup table may be generated in advance and stored in a storage means (eg, a memory) in order to map the left and right wheel speeds to the positions of the left and right levers.

The method of generating the lookup table, for example, first measures the wheel speed with an RPM gauge while moving the rotor position value (rotor angle value) of the motor 140 step by step. If the lawn mower is equipped with a mower speed sensor, the mower speed sensor may measure the mower speed. Thereafter, a look-up table is generated by programming the step-by-step rotor position value and wheel speed, and stored in a storage means such as a memory.

Motor(140)

The motor 140 includes a right motor 142 and a left motor 144 as shown in FIGS. 1 and 3 .

The right motor 142 generates a right torque (right rotational force) according to the right motor driving signal L _R input from the motor control unit 130 and transmits it to the right gear 152 of the gear unit 150 , and the left motor Reference numeral 144 generates a left torque (left rotational force) according to the left motor driving signal L _L input from the motor control unit 130 and transmits it to the left gear 154 of the gear unit 150 .

gear part (150)

The gear unit 150 transmits the right torque generated by the right motor 142 to the right lever 212 to the right gear 152 and the left torque generated by the left motor 144 to the left lever 214 . It includes a left gear 154 .

The right gear 152 is fixedly coupled to the rotation shaft of the right motor 142 to transmit the right torque generated by the right motor 142 to the right lever 212, as shown in FIG. It includes a pinion gear (152A, Pinion Gear) rotating according to the rack (Rack) member (152B) having a sector shape fixedly coupled to the right lever.

A rack gear 52 is formed on the outer circumferential surface (a fan-shaped arc) of the rack member 152B, and the rack gear 52 and the pinion gear 152A mesh with each other to rotate the pinion gear 152A so that the rack member 152B is rotated. Back-and-forth movement.

That is, the right gear 152 has a rack-and-pinion gear structure, and transmits the right torque generated by the right motor 142 to the right lever 212 according to the rack-and-pinion gear structure.

The left gear 154 also has a rack-and-pinion gear structure like the right gear 152 , and transmits the right torque generated by the left motor 144 to the left lever 214 according to this rack-and-pinion gear structure. The detailed structure of the left gear 154 is replaced with the description of the right gear 152 .

The lever 210 is, as shown in FIGS. 1 and 3 , the right lever 212 and the left gear 154 whose positions are changed back and forth according to the forward and backward reciprocating motion of the rack member 152B included in the right gear 152 . ) includes a left lever 214 whose position is changed back and forth according to the forward and backward reciprocating motion of the rack member included in it. As such, as the lever 210 is mechanically (gear) connected to each motor for automatic operation, a system configuration for automatic operation is possible.

The engine 220 may be a gasoline engine that provides driving power to the lawn mower according to the positions of the right lever 212 and the left lever 214 .

For reference, if the left and right wheel speeds are the same, go straight, if there is a difference, turn right or left, and if the signs are different, it becomes a spin (zero turn).

sensor unit (160)

The sensor unit 160 is mounted on the lawn mower and measures an actual speed and an actual attitude angle of the lawn mower running according to the engine 220 .

In order to measure the actual speed and the actual attitude angle, the sensor unit 160 is configured to include a plurality of sensors such as a radar sensor, a GPS sensor, a gyro sensor, and an acceleration sensor, and based on the sensing values measured by each sensor It is possible to measure the actual speed (v _m ) and the actual attitude angle (θ _{m ) of the running lawnmower.}

Error calculator (170)

_{The error calculator 170 calculates the difference between the actual speed v m} input from the sensor unit 160 _{and the target speed v t} input to the adder/subtractor 110 to calculate the speed error (v _error). = v _m - v _{t ) is generated, and the difference between the actual attitude angle θ m} input from the sensor unit 160 _{and the target attitude angle θ t} input to the adder/subtractor 110 is calculated to obtain an attitude angle error θ _error = θ _m - θ _t ) is generated and fed back to the adder/subtractor 110 .

Then, the adder/subtractor 110 adds and subtracts the velocity error v _error and the attitude angle error θ _error to the target velocity v _t and the target attitude angle θ _t , respectively, to obtain the actual velocity v _m and the actual attitude. The error of angle θ _{m is compensated.}

As such, the engine-driven lawn mower of the present invention includes an addition/subtractor 110 , an integrated control unit 120 , a motor control unit 130 , a motor 140 , a gear unit 150 , a sensor unit 160 , and an error calculation unit ( 170), so that automatic driving and automatic steering control of the engine-driven lawn mower operated by the existing manual lever is possible, so that the weeding operation can be performed automatically, and the operation that requires repeated operation By performing the weeding operation in a space automatically, it is possible to increase the user's convenience. Furthermore, it is possible to increase efficiency by configuring an automatic operation and automation system of various mechanical devices operated by levers.

6 is a flowchart illustrating a control method for automatic operation of an engine-driven lawn mower according to an exemplary embodiment of the present invention.

Referring to FIG. 6 , first, in S610 , the integrated control unit receives the bypassed target speed and target attitude angle through an adder and subtracter, and the left and right sides of the lawn mower from the input target speed and target attitude angle Calculate the wheel speed.

Calculation of the left and right wheel speeds, for example, after calculating the turning radius of a lawn mower consisting of a drive wheel and a caster wheel, can be calculated from the calculated turning radius, Calculation of the left and right wheel speeds ω _L and ω _R may be performed according to the execution of the program code in which Equations 1 to 5 are programmed.

The target speed and target attitude angle may be pre-calculated before S610. For example, after installing a plurality of landmarks having a certain size at the corner of the work space, the lawn mower is positioned at a constant position inside and outside the work space. While rotating in place, the landmark is recognized through a sensor provided therein. Thereafter, a separate processor unit divides the work space into grid intervals according to a result of recognizing the landmark, and calculates an optimal driving path from the partitioned grid intervals. Then, the target speed and the target attitude angle are calculated for each grid interval partitioned from the calculated optimal driving path.

Next, in S620, the motor control unit generates a left motor drive signal corresponding to the left lever position mapped to the left wheel speed input from the integrated control unit and a right motor drive signal corresponding to the right lever position mapped to the right wheel speed. print out

Specifically, a left lever position mapped to the left wheel speed and a right lever position mapped to the right wheel speed are calculated with reference to a lookup table indicating the relationship between the left and right wheel speeds and the left and right lever positions, and the left lever position A left motor driving signal corresponding to , and a right motor driving signal corresponding to the position of the right lever are output.

Next, in S630 , the left motor generates a left rotational force (left torque) according to the left motor driving signal, and the right motor generates a right rotational force (right torque) according to the right motor driving signal.

Next, in S640 , the left gear converts the left rotational force into a reciprocating linear motion (back and forth reciprocating motion) and transmits it to the left lever, and the right gear converts the right rotational force into a reciprocating linear motion and transmits it to the right lever.

Here, the left gear mechanically connects the left motor and the left lever according to the rack-and-pinion gear coupling method, as shown in FIGS. 1 and 2, and, likewise, the right gear and the right gear according to the rack-and-pinion gear coupling method Mechanically connect the motor and the right lever. According to such a rack-and-pinion gear coupling structure, the rotational force generated in the motor may be converted into a reciprocating linear motion (back and forth reciprocating motion) and transmitted to the lever.

Next, in S650, the step of automatically driving the lawn mower according to the reciprocating linear motion of the left lever and the right lever

After S650, a process of compensating for errors with respect to the actual speed and the actual attitude angle according to the automatic driving may be further performed.

Specifically, after S650, after the sensor unit measures the actual speed and the actual attitude angle according to the automatic operation of the lawn mower, the error calculator calculates the difference between the actual speed and the target speed to generate a speed error, , calculates a difference between the actual posture angle and the target posture angle to generate an attitude angle error. Thereafter, an adder/subtractor provided at the front end of the integrated control unit compensates for the error between the actual speed and the actual posture angle by adding or subtracting the speed error and the posture angle error to the target speed and the target posture angle, respectively.

As described above, the present invention has been mainly described with respect to the embodiment, but this is only an example and does not limit the present invention. It can be seen that various modifications and applications not exemplified are possible. For example, each component specifically shown in the embodiment of the present invention can be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

Claims (14)

In a control method for automatic operation of an engine-driven lawn mower, the method comprising:
calculating, by an integrated control unit, the left and right wheel speeds of the lawn mower from the input target speed and target attitude angle;
outputting, by the motor controller, a left motor driving signal corresponding to a left lever position mapped to the left wheel speed and a right motor driving signal corresponding to a right lever position mapped to the right wheel speed;
generating, by the left motor, a left rotational force according to the left motor driving signal, and by the right motor, generating a right rotational force according to the right motor driving signal;
converting, by the left gear, the left rotational force into a reciprocating linear motion and transmitting it to the left lever, and the right gear converting the right rotational force into a reciprocating linear motion and transmitting it to the right lever; and
performing automatic operation of the lawn mower according to the reciprocating linear motion of the left lever and the right lever
A control method of a lawn mower comprising a. The method of claim 1, wherein the delivering comprises:
The left gear mechanically connects the left motor and the left lever according to the rack and pinion gear coupling method to convert the left rotational force into a reciprocating linear motion, and the right gear is the right motor according to the rack and pinion gear coupling method and mechanically connecting the left lever to convert the right rotational force into a reciprocating linear motion. In claim 1, before the step of calculating,
Installing a plurality of landmarks having a certain size at the edge of the work space;
recognizing the landmark through a sensor provided therein, while the lawn mower rotates in place at a predetermined position inside and outside the working space;
dividing, by the processor unit, a work space at a grid interval according to a result value of recognizing the landmark, and calculating an optimal driving route from the partitioned grid interval; and
calculating the target speed and the target attitude angle for each grid interval partitioned from the calculated optimal driving path
A control method of a lawn mower further comprising a. The method of claim 1, wherein the calculating comprises:
calculating a turning radius of the lawn mower comprising a drive wheel and a caster wheel; and
calculating the left and right wheel speeds from the calculated turning radius
A control method of a lawn mower comprising a. The method of claim 1, wherein the outputting comprises:
calculating a left lever position mapped to the left wheel speed and a right lever position mapped to the right wheel speed with reference to a lookup table indicating a relationship between left and right wheel speeds and left and right lever positions; and
outputting a left motor driving signal corresponding to the left lever position and a right motor driving signal corresponding to the right lever position
A control method of a lawn mower comprising a. In claim 1,
measuring, by a sensor unit, an actual speed and an actual attitude angle according to the automatic operation of the lawn mower;
generating, by an error calculator, a difference between the actual velocity and the target velocity to generate a velocity error, and calculating a difference between the actual attitude angle and the target attitude angle to generate an attitude angle error;
Compensating for the error between the actual speed and the actual attitude angle by adding or subtracting the speed error and the attitude angle error to the target speed and the target attitude angle, respectively, by an adder/subtractor provided at the front end of the integrated control unit
A control method of a lawn mower further comprising a. In the control unit for automatic operation of an engine-powered lawn mower,
an integrated control unit for calculating left and right wheel speeds of the lawn mower according to the input target speed and target attitude angle;
a motor control unit outputting a left motor drive signal corresponding to a left lever position mapped to the left wheel speed and a right motor driving signal corresponding to a right lever position mapped to the right wheel speed;
a motor unit including a left motor generating a left rotational force according to the left motor driving signal and a right motor generating a right rotational force according to the right motor driving signal;
a gear unit including a left gear that converts the left rotational force into a reciprocating linear motion and transmits it to a left lever, and a right gear that converts the right rotational force into a reciprocating linear motion and transmits it to the right lever; and
An engine that provides driving power for automatically driving the lawn mower according to reciprocating linear motions of the left lever and the right lever
A control unit for a lawn mower comprising a. In claim 7,
a sensor unit for measuring an actual speed and an actual attitude angle according to the automatic operation of the lawn mower;
an error calculator configured to calculate a velocity error according to a difference between the actual velocity and the target velocity and to calculate an attitude angle error according to a difference between the actual attitude angle and the target attitude angle; and
An adder/subtractor provided at the front end of the integrated control unit to compensate for the error between the actual speed and the actual attitude angle by adding or subtracting the speed error and the attitude angle error to the target speed and the target attitude angle, respectively.
Control unit of the lawn mower further comprising a. The method of claim 7, wherein each of the left gear and the right gear,
The control apparatus for a lawn mower, wherein the left motor and the right motor are mechanically connected to the left lever and the right lever, respectively, according to a rack-and-pinion gear coupling structure. The method of claim 7, wherein the integrated control unit,
A control apparatus for a lawn mower, comprising: calculating a turning radius of a lawn mower including a drive wheel and a caster wheel; and calculating the left and right wheel speeds from the calculated turning radius. The method of claim 7, wherein the motor control unit,
and calculating a left lever position mapped to the left wheel speed and a right lever position mapped to the right wheel speed by referring to a lookup table indicating a relationship between left and right wheel speeds and left and right lever positions. . In claim 7,
Further comprising a processor unit for calculating the target speed and the target attitude angle,
The processor unit is
The lawn mower recognizes a plurality of landmarks installed at the corners of the working space to be worked through a sensor, and divides the working space at grid intervals according to the result of recognizing the landmarks, and optimizes the partitioned grid intervals. and calculating the target speed and target attitude angle for each grid interval from the calculated optimal driving path, and inputting the calculated target speed and target attitude angle to the integrated control unit. The method of claim 7, wherein each of the left gear and the right gear,
a pinion gear fixedly coupled to the rotation shafts of the left motor and the right motor, respectively, and rotating according to the rotation of the rotation shaft; and
and a rack member having a sector shape fixedly coupled to the left lever and the right lever, respectively. In claim 13,
and a rack gear is formed on an outer circumferential surface (a fan-shaped arc) of the rack member, and the rack gear and the pinion gear mesh with each other and the rack member performs a reciprocating linear motion according to the rotation of the pinion gear.

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