CN102183959B - Self-adaptive path control method of mobile robot - Google Patents

Abstract

A method for adaptive path control of a mobile robot, characterized in that it includes the following steps: placing at least two sequentially numbered landmark locators in the work area of the mobile robot; Long-distance signal and move towards it after searching for the signal; move to time or distance as a reference to set the reference point, obtain its virtual coordinates and store it as a key point; when receiving the short-distance signal of the road sign locator, The mobile robot obtains and stores the virtual coordinates of its current location; after completing the search of all landmark locators in turn, the mobile robot corrects the virtual coordinates of the key points; the mobile robot cruises according to the corrected virtual coordinates of the key points. The robot system using this method has the advantages of strong adaptive cruising environment capability, convenient operation, safety and reliability. In addition, the implementation cost of this method is low.

Description

Adaptive path control method for mobile robots

technical field

The present invention relates to mobile robots, in particular to path control for mobile robots.

Background technique

With the development of science and technology, robot technology is becoming more and more mature, and its application fields are becoming more and more extensive, such as household hygiene and cleaning, security patrols, etc.

Rovio, developed by WowWee, is a mobile cruising camera robot with WiFi control function. Through its built-in camera, users can view and interact with their environment through real-time video and audio streams. However, when cruising, due to the lack of a designated target and the limited recognition ability of the robot itself, the adaptability to the environment is poor, so there is no relatively reliable cruising path.

Most of the traditional security monitoring systems use the pan-tilt positioning and rotation method to take pictures, and the area of the pictures taken is limited. If it is compensated by the number, the workload and cost of communication, storage, and defense will increase. At the same time, the monitoring system cannot be moved. If you want to If you want to monitor multiple areas, you have to increase the monitoring equipment, which increases the cost.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the technical defects in the background technology and provide an adaptive path control method for a mobile robot with a reliable cruising path.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A method for adaptive path control of a mobile robot, comprising the following steps:

1) Place at least two sequentially numbered landmark locators in the working area of the mobile robot;

2) The mobile robot searches for the long-distance signals sent by each landmark locator in sequence according to the serial number, and moves towards it after searching for the long-distance signal of the current landmark locator;

3) The mobile robot sets a reference point with time or its movement distance as a reference, obtains its virtual coordinates and stores them as key points in the storage module;

4) When the mobile robot receives the short-distance signal from the landmark locator, it uses its current location as a key point to obtain its virtual coordinates and store it in the storage module;

5) The mobile robot corrects the virtual coordinates of key points after completing the search of all landmark locators;

6) The mobile robot cruises according to the virtual coordinates of the corrected key points.

In the optimization scheme of the method of the present invention, the road sign locator includes a charging stand, and the signal of the charging stand is stronger than the signals of other road sign locators;

In the optimization scheme of the method of the present invention, in step 3), if the mobile robot loses the signal of the current landmark locator, it returns to the last key point, and then re-selects a direction to move.

In the further optimization scheme of the method of the present invention, in step 4), the mobile robot sends an arrival signal after receiving the short-distance signal from the landmark locator, and the landmark locator stops sending the long-distance signal within a period of time after receiving the arrival signal and close range signals.

In the further optimization scheme of the method of the present invention, in step 3), the mobile robot uses its current location as a key point when detecting an obstacle, obtains its virtual coordinates and stores it in the storage module;

In the further optimization scheme of the method of the present invention, in step 3), the mobile robot keeps receiving the signal of the landmark locator in the process of avoiding the obstacle, and if the signal is lost, it moves backward to the key point when the obstacle is detected, and then restarts Choose a direction to move;

In a further optimization scheme of the method of the present invention, in step 3), the mobile robot continues to move forward after deflecting 60° to the left or right when an obstacle is detected, and then deflects 60° to the right or to the left when no obstacle is detected. , and store the position as a key point in the storage module.

In a further optimization scheme of the method of the present invention, the correction in step 5) includes modification of virtual coordinates of key points, addition of key points, and deletion of key points.

In a further optimization scheme of the method of the present invention, the long-distance signal and the short-distance signal of the road sign locator are 360° omnidirectional signals.

In a further optimization scheme of the method of the present invention, the signal of the road sign locator is an infrared signal or an ultrasonic signal.

Compared with the prior art, the beneficial effects of the adaptive path control method of the mobile robot disclosed in the present invention are as follows:

The method of the present invention overcomes the defects that the traditional security monitoring system cannot move and cruise, and the existing mobile robot has relatively poor ability to recognize the environment, and there is no safe and reliable target for walking. The mobile robot using the method has strong adaptive cruise environment ability, convenient operation, and safety. Reliable advantages, in addition, the method is less costly to implement.

Description of drawings

Fig. 1 is the structural block diagram of the mobile robot in the preferred embodiment of the present invention;

Fig. 2 is the schematic diagram of the mobile robot in the preferred embodiment of the present invention;

Fig. 3 is the road sign locator piloting planning diagram of the mobile robot in the home environment situation in the preferred embodiment of the present invention;

Fig. 4 is the control schematic diagram of the road sign locator in the preferred embodiment of the present invention;

Fig. 5 is a control schematic diagram of the remote controller in a preferred embodiment of the present invention;

Fig. 6 is the control schematic diagram of the mobile robot in the preferred embodiment of the present invention;

Fig. 7 is a flowchart of a preferred embodiment of the present invention;

Fig. 8 is a flow chart of the mobile robot searching for a landmark locator in a preferred embodiment of the present invention;

Fig. 9 is a schematic diagram of the key points of the mobile robot in a preferred embodiment of the present invention without obstacles;

Fig. 10 is a schematic diagram of the key points of the mobile robot in the preferred embodiment of the present invention in the case of obstacles;

Fig. 11 is a schematic diagram of a mobile robot discarding key points in a preferred embodiment of the present invention.

Detailed ways

The adaptive path control method of the mobile robot of the present invention will be further described in detail below in conjunction with the specific embodiments and with reference to the accompanying drawings.

Please refer to FIG. 1 to FIG. 11 , which are a preferred embodiment of the present invention.

The present embodiment is illustrated by taking a household monitoring robot as an example. The system using the method of the present invention includes a mobile robot (Fig. 2), a charging stand S, a road sign locator A-H and a remote controller. Motion module, monitoring module, signal transceiver module, obstacle detection module, acquisition module, storage module and control module, the charging stand S is used as a landmark locator when the mobile robot is not charging, and the signal strength it sends is greater than that of the landmark locator A-H The signal strength of charging base S and road sign locator A-H continuously sends 360 ° all-round long-distance signal and 360 ° all-round short-distance signal according to a certain frequency, and the signal sent preferably infrared signal or ultrasonic signal, adopts infrared signal in the present embodiment .

As shown in Figure 4, the chip of the road sign locator in the present embodiment adopts TK98P01, comprises long-distance signal transmitter, short-distance signal transmitter, power supply (generally dry cell or accumulator) and first receiver, second receiver , the first receiver is used to receive the signal from the remote controller, and the second receiver is used to receive the signal from the mobile robot.

As shown in FIG. 5 , the chip of the remote controller in this embodiment adopts TK98P01, including a signal transmitter, a signal transmitter, a power supply (usually a dry cell or a storage battery), a display screen and a keyboard.

As shown in Figure 6, the main control chip of the mobile robot in this embodiment adopts STM32F101. The drive module includes left and right drive wheels and universal wheels; the obstacle detection module includes five (front, left, right, left middle, right middle) detection sensors for the wall and five ground detection sensors (front, left, right, middle left, middle right); the power module adopts dry batteries or accumulators that can be recharged many times; signal; the monitoring module includes video acquisition equipment (camera) and audio acquisition equipment (MIC); the acquisition module is used to measure the speed of the left and right driving wheels to obtain the moving distance of the mobile robot, and measure the speed of the universal wheel to obtain the motion state of the mobile robot; Use the gyroscope to obtain the moving direction information of the mobile robot.

As shown in FIG. 6, it is a flow chart of this embodiment. The implementation process will be described in detail below with reference to FIG. 3 and FIG. 7 .

Step 1) Place the rechargeable seat S at the gate of the home environment, place the road sign locators A-H at the door of the kitchen, study, balcony, bedroom, and bathroom, and then place them at key positions (such as window sills or places where valuables are placed) Waypoint locator.

Step 2) Set corresponding labels for each landmark locator through the remote control, and at the same time tell the mobile robot the number of landmark locators and the sequence of searching for landmark locators, and then start the command, and the mobile robot will search for the current landmark locator. After the long-distance signal, keep receiving the signal and move towards it until the mobile machine receives the short-distance signal of the current landmark locator; wherein, before the mobile robot receives the short-distance signal of the landmark locator, if it receives other short-distance signals The signal of the landmark locator, the mobile robot ignores the received signal, and will not take action on the received signal.

The first receiver (T101) of the landmark locator determines its serial number according to the different signals sent by the remote controller. If the command 0XAA0X01 is received, it means that the landmark locator is the first landmark locator to be searched for by the mobile robot. The number is A; and so on, when the road sign locator receives 0XAA0X02, ..., 0XAA0X09; the numbers are B, C, D, E, F, G, H, S; by default, S is the charging station , generally the last number. After the receiver of the mobile robot receives the command 0Xbb0X09 from the remote controller, it indicates that the number of landmark locators is 9, and the buzzer whistle indicates that the setting is successful. The 360° all-round long-distance signal transmitter of the landmark locator sends the command 0X01 (corresponding to the number of the landmark locator) to guide the mobile robot to move to the landmark locator.

Step 3) The mobile robot sets a reference point after a predetermined time (such as 5 seconds) or walks a predetermined distance (such as 20cm), obtains its virtual coordinates and stores them as key points in the storage module, as shown in Figure 9, the charging stand There are 4 key points A1-A4 between S and landmark locator A.

Please refer to Figure 9. After receiving the 0X01 signal from landmark locator A, the mobile robot starts to move towards landmark locator A. Collect once every 200 microseconds during the process, and make accumulations of L1 and L2 (if there is a failure, do not accumulate); at the same time, the acquisition module measures the speed of the guide wheel (that is, captures the high level of the photoelectric code), and every 200 microseconds during walking Collect once and make accumulation L3 (if there is a failure, do not make accumulation); gyroscope direction deflection sensor (angular velocity), collect once every 2 milliseconds during walking, as an important parameter of the mobile robot's walking line and pre-deflection angle, make accumulation ∮1; the mobile robot walks mainly in four motion states: straight forward, straight backward, two-wheel simultaneous motion to the left, and two-wheel simultaneous motion to the right deflection; during straight-line walking, the MCU of the mobile robot calculates L1 every 2 milliseconds ', L2' (L1', L2' are the movement distance of the mobile robot within 2 milliseconds) to adjust the speed of the left and right wheels to ensure that the walking path trajectory is a straight line, and the gyroscope collects ∮1' every 10 milliseconds (∮1' is the angle at which the mobile robot deviates within 10 milliseconds), make a secondary correction of the angular velocity, adjust ∮1 to compensate for the fluctuations in walking, and modify the parameters of the left and right road wheel motors during normal distribution; During deflection walking, the MCU of the mobile robot calculates L1", L2", ∮1" every 2 milliseconds (L1", L2" are the moving distances of the mobile robot within 2 milliseconds, and ∮1" mobile robots deviate within 10 milliseconds Angle) to ensure that the angle of deflection is expected; when the mobile robot travels to the landmark locator in a normal straight line, the calculation of the virtual coordinates of the key points is calculated every 5 seconds (no fault occurs), and the landmark locator A The virtual coordinates (Xa, Ya) are calculated by the following company: Xa=(L1+L2)/2; (Used when preparing for learning cruise) is ((L1+L2)/2, ∮1), and the coordinates here are polar coordinates.

Step 4) When the mobile robot receives the short-distance signal from the landmark locator, it uses its current location as a key point to obtain its virtual coordinates and store them in the storage module. The calculation of its coordinates is similar to that in step 3), I won't explain it here.

When the mobile robot is close to the landmark locator, the short-distance signal transmitter sends an order 0X11 to notify the mobile robot that it has arrived at the destination and does not move forward; the signal transmitter of the mobile robot sends the second receiver of the order 0X21 to the landmark locator (T102), indicating that he has arrived, the road sign locator temporarily turns off the 360° all-round long-distance signal transmitter and short-distance signal transmitter, and then turns it on again after a period of time (such as 1 minute), so as to prevent the next road sign locator from sending The long-distance signal is interfered.

After the mobile robot completes the path planning of the charging stand S and the landmark locator B, it completes the alignment of the landmark locators B and C, C and D, D and E, E and F, F and G, G and H in sequence. And the path planning between the road sign locator H and the charging stand S.

After the settings and protocol definitions are complete, proceed to the next step.

Step 5) the mobile robot corrects the virtual coordinates of the key points after completing the search of all landmark locators;

After the mobile robot completes the path planning of the entire work area, it corrects the coordinates of key points in its cruising path: the mobile robot moves towards the landmark locator A after receiving the 360° omnidirectional long-distance signal from the landmark locator A; reads the road section SA The virtual coordinates of all the key points, and then the mobile robot moves in turn according to the orientation shown by the virtual coordinates of the key points. When the distance signal is the key point), judge whether its virtual coordinates are the virtual coordinates in the storage module; if yes, the calculation of the virtual coordinates of the key points is good; if not, the parameters in the first obstacle avoidance If there is a deviation, then the current position of the mobile robot is used as a new key point and its virtual coordinates are stored in the storage module, so the correction of the road section SA is completed; then follow this step to continue to complete the virtual coordinates of the key points of other road sections fix.

Step 6) The mobile robot cruises according to the virtual coordinates of the corrected key points.

After the mobile robot completes the correction of the virtual coordinates of the key points of all 9 road sections, the mobile robot no longer receives the 360° all-round long-distance signal and short-distance signal of the landmark locator. At this time, the landmark locator can be withdrawn, and then the mobile robot The virtual coordinates of the key points of each road section are read in turn and moved to complete the self-learning cruising path.

Special case handling during the operation of the mobile robot:

1. Handling of obstacle avoidance:

The above step 3) describes the mobile robot when there is no obstacle between any two landmark locators, but in actual situations, the robot will encounter various failures, please refer to Figure 10 to Figure 11, if the obstacle detection of the mobile robot The module senses that there is an obstacle ahead (the detection distance is generally 5CM to 30CM, and the detected obstacle includes obstacles and potholes on the road surface), the mobile robot stops running, takes this point as a key point, calculates its virtual coordinates and stores them, and then Rotate 60° to the left or right in place and continue moving. During the barrier process, if the mobile robot loses the signal of the current landmark locator, it will go back in a straight line until it returns to the previous key point, and then choose a direction to proceed. Obstacle avoidance: The obstacle avoidance experiment proves that the mobile robot preferably avoids obstacles at an angle of 60°, the obstacle avoidance effect is reliable and the algorithm is relatively simple. Mobile robots can avoid obstacles in the following two ways:

A. Please refer to Figure 10, the mobile robot detects an obstacle at point A2, takes point A2 as a key point, obtains its virtual coordinates (X _A2 , Y _A2 ) and stores them, then turns left 60° and moves forward, at point A3 After the obstacle is no longer detected at , take point A3 as the key point at this time, then turn right 60° and obtain its virtual coordinates (X _A3 , Y _A3 ) and store them, and move on to the distance between point A2 and point A3 Arrive at point A4, use point A4 as the key point, turn right 60° and obtain its virtual coordinates (X _A4 , Y _A4 ) and store them, move on to the point A5 and set point A5 As a key point, turn right 60° and obtain its virtual coordinates (X _A5 , Y _A5 ) and store them, then turn left 60° and continue moving forward, so as to complete the obstacle avoidance.

B. Please refer to Figure 11, the mobile robot detects an obstacle at point A2, takes point A2 as a key point, obtains its virtual coordinates X _A2 , Y _A2 ) and stores them, then turns left 60° and moves forward to reach the point by a predetermined distance Obstacles can still be detected after A3', the mobile robot abandons the point A'3 as the key point, and then the mobile robot will go straight back to the key point A2, then turn right 120°, and then advance the predetermined distance to reach the point A3, at this time no longer When an obstacle is detected, the mobile robot takes point A3 as a key point, obtains its virtual coordinates (X _A3 , Y _A3 ) and stores them, then turns left 60° and continues to advance to point A4 for a predetermined length, and then uses point A4 as a key point to obtain Its virtual coordinates (X _A4 , Y _A4 ) are stored, then turn left 60° and continue forward to reach point A5 for a predetermined distance, take point A5 as a key point, turn left 60° and obtain its virtual coordinates (X _A5 , Y _A5 ) and Store it, then turn right 60° and continue to move forward, so as to complete the avoidance of obstacles.

In method B for obstacle avoidance, the predetermined distance for the mobile robot to move forward can be manually set, and the user can properly set it according to the size of the indoor obstacle, which can improve its cruising efficiency.

2. Troubleshooting when the mobile robot slips or gets stuck:

When the acquisition module can receive the signal of the speed measurement of the left wheel or the speed measurement of the right wheel, but there is no signal of the speed measurement of the universal wheel, the mobile robot thinks that the left and right wheels are slipping or are stuck, the mobile robot stops moving forward, and then moves backward in a straight line for a predetermined time. distance until the acquisition module receives the universal wheel speed measurement signal at the same time. At this time, the mobile robot takes this point as a key point, obtains its virtual coordinates and stores them, and then chooses a direction to move forward.

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, several equivalent substitutions or obvious modifications are made without departing from the concept of the present invention, and the performance or use is the same, all should be regarded as belonging to the present invention by the submitted claims The scope of patent protection determined by the book.

Claims (10)

1. a mobile robot Adaptive Path control method is characterized in that comprising following step:

1) in mobile robot's perform region, places at least two road sign steady arms that are numbered in order;

2) mobile robot searches the distant signal that each road sign steady arm sends successively by number order, and after the distant signal that searches current road sign steady arm to its motion;

3) mobile robot serves as with reference to reference point being set, trying to achieve its virtual coordinates and it is stored into memory module as key point with time or its move distance;

4) mobile robot as key point, tries to achieve its current position its virtual coordinates and it is stored into memory module when receiving the closely signal of road sign steady arm;

5) mobile robot's virtual coordinates to key point after the search of finishing all road sign steady arms is revised, and comprising: according to number order, the mobile robot receives after the distant signal of road sign steady arm to this road sign steady arm motion; Read all crucial virtual coordinates of this road sign steady arm corresponding road section, and successively by the motion of the orientation shown in the virtual coordinates of key point, simultaneously distance and direction of motion are stored into storage block, when last key point that arrives this highway section, during the key point that is mobile apparatus when receiving short-range signal, judge whether its virtual coordinates is corresponding virtual coordinate in the memory module; If not, then the current position point of mobile robot is stored in the memory module as newly-increased key point and with its virtual coordinates, so finish the correction in this highway section; Continue to finish the correction of the virtual coordinates in other highway sections then by this step;

6) mobile robot cruises by the virtual coordinates of revised key point.

2. mobile robot's as claimed in claim 1 Adaptive Path control method, it is characterized in that: described road sign steady arm comprises cradle, and the signal intensity of described cradle is greater than the signal intensity of other road sign steady arms.

3. mobile robot's as claimed in claim 1 Adaptive Path control method is characterized in that: in step 3), if the mobile robot loses current road sign fixture signal, then return a key point, reselect a direction motion again.

4. as any described mobile robot's of claim 1 to 3 Adaptive Path control method, it is characterized in that: in step 4), the mobile robot sends an arriving signal after receiving the closely signal of road sign steady arm, the road sign steady arm stops to send distant signal and signal closely in a period of time after receiving arriving signal.

5. mobile robot's as claimed in claim 4 Adaptive Path control method, it is characterized in that: in step 3), the mobile robot when detecting obstacle with its current position as key point, try to achieve its virtual coordinates and it be stored into memory module.

6. mobile robot's as claimed in claim 5 Adaptive Path control method, it is characterized in that: in step 3), the mobile robot keeps receiving the signal of road sign steady arm in the process of avoidant disorder, if lossing signal then straight line retreats into the key point when detecting obstacle is reselected a direction motion again.

7. mobile robot's as claimed in claim 6 Adaptive Path control method, it is characterized in that: in step 3), the mobile robot moves on after 60 ° of the deflections when detecting obstacle to the left or to the right, when no longer detecting obstacle,, simultaneously this position is stored into memory module as key point to the right again or 60 ° of deflections left.

8. mobile robot's as claimed in claim 7 Adaptive Path control method is characterized in that: the correction in the described step 5) comprises that the virtual coordinates of key point revises, increases key point and deletion key point.

9. mobile robot's as claimed in claim 8 Adaptive Path control method is characterized in that: the distant signal of described road sign steady arm and closely signal be 360 ° of comprehensive signals.

10. mobile robot's as claimed in claim 9 Adaptive Path control method, it is characterized in that: the signal of described road sign steady arm is infrared signal or ultrasonic signal.

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