KR20090074410A - System and method for controlling drive of robot - Google Patents

Abstract

A system and a method for driving control of a robot are provided to detect an error in slip and travel distance of the robot from a laser beam reflected from the road surface and compensate the error. A driving control system of a robot comprises an optical sensing unit(30) receiving the light reflected off the road surface, a travel distance operation unit(32) detecting the travel direction and distance of the robot by comparing the difference between the optical signals of the reflected light, a driving control unit(22) which controls wheels(2,4) to guide the robot to the destination, computes the travel distance by comparing the sensed travel direction and distance with a driving control value, and perform driving control for correcting the travel distance error, and a robot driving unit rotating the wheels so that the error distance is compensated according to the driving control for error correction of the driving control unit.

Description

Travel control system of robot and its method {System and Method for Controlling Drive of Robot}

The present invention relates to a travel control system and a method of a robot for detecting slip travel of a robot and ensuring straightness at the time of travel by detecting light information irradiated on a road surface on which the robot travels.

In the related art, a robot is fixedly disposed at a certain place or a workplace, and has been used only to perform a simple function of repeatedly performing only a pre-programmed operation or task. Recently, robot control technology and driving motor technology have been developed. As a result, robots can be applied not only to various purposes, but also to develop robots that can be moved according to their purpose.

These robots are equipped with various sensors and autonomous driving control algorithms to move in the desired direction while avoiding obstacles. In some cases, it is possible to use a form of walking using joint motion, but nowadays, wheels that are rotationally driven by a motor or a driving engine are mainly applied as a means capable of appropriately controlling the direction and distance of movement.

On the other hand, in the case of a robot using wheels as a driving means, a slip phenomenon occurs due to a decrease in friction between the wheels and the bottom surface when driving the wheels, or a distance when driving straight due to mechanical deviation between both wheels. In order to minimize the error of driving performance, bar codes are installed on the floor of the road where the robot travels, and the bar code installed by the robot is read to ensure accurate driving. Various methods are available such as a built-in gyroscope to correct the deviation direction when driving according to the azimuth of the target position, or to install an encoder on the wheel and to feed back the encoder pulse obtained from the encoder to reduce the driving error. It is taking.

However, in the case of the barcode installation method, the gyroscope built-in method, and the encoder method applied to reduce the error factor of the driving performance, there is a major factor in the cost increase due to the installation or mounting of expensive equipment, and inconvenience to the user. Not only does it follow, but there is a problem in that there is a limit in the reliability of the correction of the driving error of the robot.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to detect a driving error by optical information obtained from a road surface on which a robot travels so that reduction of slip error and straightness can be ensured. It is to provide a traveling control system and a method of the robot.

In order to achieve the above object, according to the system of the present invention, in the traveling control system of the robot traveling by the rotational drive of the wheel, the light sensing means for irradiating light to the road surface on which the robot travels and receiving and sensing the reflected light And a distance calculation processing means for comparing and analyzing an optical signal difference of the reflected light sensed by the light sensing means to detect a moving direction and a distance of the robot, according to the driving control value so that the robot reaches a desired position. Travel control means for controlling the driving of the wheel, calculating the travel distance error by comparing the travel direction and the travel distance detected by the travel distance calculation processing means with the travel control value, and performing drive control to correct the travel distance error. And rotationally driving the wheel by driving control of the travel control means, and correcting an error of the travel control means. According to the drive control for providing a traveling control system for a robot comprising a robot driving drive means for rotating the wheel so that the error distance is compensated.

According to the method of the present invention to achieve the above object, in the traveling control method of the robot traveling by the rotational driving of the wheel, the wheel in accordance with the driving control value to reach the desired position in the traveling control means of the robot Controlling the driving of the robot; and receiving the reflected light by irradiating light onto the road surface on which the robot travels in the moving state of the robot, and comparing and analyzing the difference between the optical signals of the reflected light and Detecting a movement distance; calculating a movement distance error by comparing the movement direction and the movement distance detected by the optical signal with the traveling control value by the traveling control means; and the calculated movement distance by the traveling control means. And driving the wheels to be compensated by the error distance to correct the error. It provides a drive control method of a robot according to Gong.

As described above, according to the present invention, the robot detects the slip state of the robot and the deviation of the target moving distance from the laser light reflected by irradiating the laser light onto the road surface while the robot is traveling, thereby compensating for the error to enable accurate driving. As a result, by applying a laser beam having a low cost and high efficiency, the cost can be reduced and the robot can guarantee more accurate driving performance.

Hereinafter, the present invention configured as described above will be described in detail with reference to the accompanying drawings.

That is, Figure 1 is a view showing the overall configuration for the travel control system of the robot according to the present invention.

As shown in FIG. 1, the traveling control system of the robot according to the present invention includes first and second wheels 2 and 4, first and second motors 6 and 8, and first and second motors. Driver 10, 12, first and second steering mechanisms 14, 16, first and second steering drivers 18, 20, travel control 22, key input 24, wireless communication module 26 ), An external input port 28, a laser sensing unit 30, and a movement distance calculation processing unit 32.

The first and second motors 6 and 8 rotate the first and second wheels 2 and 4 according to the driving of the first and second motor drives 10 and 12, respectively, so that the robot moves straight. The first and second motor drivers 10 and 12 are driven according to the driving control of the driving controller 22 to rotate and drive the first and second motors 6 and 8, respectively. .

The first and second steering mechanisms 14 and 16 are installed on the first and second wheels 2 and 4, respectively, and are driven by the driving of the first and second steering drives 18 and 20. The operation of changing the running directions of the first and second wheels 2 and 4 to the right or the left is performed.

Here, the first and second steering mechanisms 14 and 16 and the first and second steering drives 18 and 20 may be wheels without steering each wheel 2 or 4 itself according to the specifications of the robot. It is possible to steer by using the rotational speed difference of, or if it is provided with a separate steering means is not necessarily provided.

The driving controller 22 is configured to drive the robot in a straight direction in accordance with driving information input from the key input unit 24, the wireless communication module 26, or the external input port 28. And driving control of the second motor driving units 6 and 8, and driving control of the first and second steering drives 18 and 20 in a direction desired by the first and second wheels 2 and 4. Calculate the moving direction errors and the moving distance errors of the first and second wheels 2 and 4 according to the driving detection data from the moving distance calculating processor 32, and compensate for the errors. Control to drive the first and second wheels 2 and 4 is performed.

The key input unit 24 is capable of inputting driving information for driving the robot in the desired direction by the user's key input, the wireless communication module 26 is remote by short-range wireless communication By operation, the user can receive the driving information of the robot by using a remote controller or wireless communication with a fixed robot control means, and the external input port 28 has various driving information or driving program information. Equipped with an included memory card, or can be connected to the external computing means by wire to receive the driving information.

The laser sensing unit 30 is for irradiating the laser light at a predetermined angle with respect to the road surface on which the robot travels and for receiving the laser light reflected from the road surface, and the movement distance processing unit 32 is the laser sensing unit. Image data is generated by capturing the reflected light from the road surface received at 30, and the travel direction data and the travel distance of the first and second wheels 2, 4 are calculated based on the image data to calculate the travel detection data. The traveling control unit 22 is provided.

Here, as shown in FIG. 2, the laser sensing unit 30 and the movement distance calculating processor 32 include a laser diode 40, a light emitting lens 42, a light receiving lens 46, and an image pickup sensor 48. ), The signal amplifier 50, the analog-to-digital converter 52, the movement distance calculation unit 54 is configured.

The laser diode 40 generates a laser light signal, and the light emitting lens 42 is disposed on the road surface 44 so that the laser light is uniformly focused on a predetermined area of the road surface 44 on which the robot travels. It is fixed at a predetermined angle with respect to the laser beam, and transmits the laser light from the laser diode 40 to irradiate a predetermined area of the road surface 44, the light receiving lens 46 is a predetermined portion of the road surface 44 In order to efficiently receive the laser light irradiated and reflected on the area, the laser beam is fixed to a predetermined angle with respect to the road surface 44, and receives the laser light reflected from the road surface 44 to the image pickup sensor 48. Will be delivered.

The image pickup sensor 48 generates an image signal by capturing the reflected light from the road surface 44 received through the light receiving lens 46 at least thousands of frames per second, which is a constant number of CMOS image sensors. It is arranged in a form.

The signal amplifier 50 amplifies an image signal of the laser beam captured by the image pickup sensor 48, and the analog-to-digital converter 52 converts the analog image signal of the signal amplified laser beam into digital data. To convert.

The moving distance calculating unit 54 compares and analyzes each of the digitally converted image data, estimates the moving direction and the moving distance of the robot based on the data difference value of the image, and calculates the driving detection data according to the driving control unit. To 22.

As shown in FIG. 3, the movement distance calculating unit 54 calculates the movement direction and the movement distance when the robot travels on the X and Y axes. The relationship between the moving direction and the moving distance is shown in Table 1 below.

  Robot's movement state     X-axis travel     Y-axis travel     + X-axis movement       increase       none     X-axis movement       decrease       none     + Y-axis movement       none       increase     -Y-axis movement       none       decrease     X + Y axis movement       increase       increase  (-X) + Y-axis movement       decrease       increase   X + (-Y) axis movement       increase       decrease   (-X) + (-Y) axis movement       decrease       decrease

The moving distance calculating processor 32 includes the moving axis direction and the moving distance in the driving detection data according to the moving direction and the moving distance of the robot as shown in Table 1, and transmits the same.

On the other hand, the driving control unit 22 compares the moving axis direction and the moving distance data of the driving detection data provided from the moving distance calculating unit 54 with the original driving control data to accumulate distance values which deviate according to an error occurrence. And the first and second wheels 2 and 4 are disposed at opposite values of the departure distance value so as to compensate for the accumulated departure distance value by performing error correction when the accumulated departure distance value is greater than or equal to a predetermined set value. Control to rotate.

That is, as shown in FIG. 4, for example, when the robot is deviated in the + X axis direction from the normal track according to the straight running in the Y axis direction, the accumulated deviation distance value in the + X axis direction is greater than or equal to the set value. Is detected, the driving controller 22 controls the driving of the first and second motors 6 and 8 and the first and second steering drives 18 and 20 so that the robot is left by the accumulated deviation distance value. It is moved in the (-X axis) direction to correct the error.

Further, when the robot is separated from the normal trajectory in the Y-axis direction in the -X axis direction, if the deviation distance value accumulated in the -X axis direction is detected to be greater than or equal to a set value, the robot is right by the accumulated escape distance value. Move to (-X axis) to correct the error.

On the other hand, the traveling control unit 22 in the opposite direction by the departure distance value by the same process even if the departure distance in the -Y axis direction or + Y axis direction when the robot travels straight in the X-axis direction To correct the error.

Next, the operation of the present invention made as described above will be described in detail with reference to the flowcharts of FIGS. 5 and 6.

First, the slip driving detection and the slip avoidance operation of the robot while driving will be described in detail with reference to FIG. 5.

First, the driving controller 22 controls the first and second motor drivers 10 and 12 according to the driving information received from the key input unit 24, the wireless communication module 26, or the external input port 28. By rotating the first and second motors 6 and 8, the first and second wheels 2 and 4 are rotated to drive the robot (step S10).

In this state, the laser light signal generated from the laser diode 40 of the laser sensing unit 30 is irradiated to a predetermined region of the traveling road surface 44 via the light emitting lens 42 and reflected from the road surface 44. The laser beam is transmitted to the image pickup sensor 48 via the light receiving lens 46 to be picked up at a rate of thousands of frames or more per second to generate an image signal.

The movement distance calculating unit 54 receives the image data amplified and digitally converted by the signal amplifying unit 50 and the analog-digital converter 52, respectively, and compares and analyzes the difference values of the images, thereby substantially moving the robot. Distance data is acquired (step S11).

The movement distance calculation processing unit 32 transmits driving detection data including the acquired movement distance data to the driving control unit 22, and the driving control unit 22 sets an actual movement distance of the driving detection data in advance. It is judged whether or not the actual travel distance is smaller than the travel set value in comparison with the travel set value (step S12).

As a result of the determination, if it is determined that the actual moving distance is smaller than the preset traveling setting value, the driving control unit 22 determines that an error is generated due to slippage due to a decrease in frictional force between the wheel and the road surface, and applies the slip avoidance algorithm. In order to compensate for the generated distance, the first and second motor driving units 10 and 12 are driven and controlled (step S13).

However, if it is determined that the actual moving distance is not smaller than the preset travel setting value, the driving control unit 22 travels from the key input unit 24, the wireless communication module 26, or the external input port 28. It is determined whether the driving of the robot according to the information is completed (step S14). If it is determined that the driving of the robot is completed, the driving of the robot is terminated (step S15).

Next, with reference to the flowchart of FIG. 6, the operation | movement which correct | amends the deviation direction and distance in a straight run state of a robot is demonstrated in detail.

First, in a state in which the robot is traveling by rotating the first and second wheels 2 and 4 (step S20), the driving controller 22 determines whether the movement direction of the robot is a straight driving in the Y-axis direction. (Step S21), if it is determined that the movement is in the Y-axis direction, the process proceeds to step S22 and the driving direction of the robot and the laser beam reflected from the traveling road surface by the laser sensing unit 30 and the movement distance calculation processing unit 32; The movement distance is acquired (step S22).

The driving controller 22 compares the driving detection data including the driving direction and the movement distance data from the movement distance calculation processor 32 with the driving control value while the robot moves straight in the Y-axis direction. It is determined whether the departure distance in the axial direction exceeds a preset departure setting value (step S23).

As a result of the determination, if it is determined that the departure distance in the X-axis direction exceeds a preset departure setting value, the driving controller 22 determines whether the departure distance is a departure to the + X axis (step S24).

If the X-axis deviation distance is determined to be a deviation distance in the + X axis direction, the driving controller 22 corrects the deviation by moving away in a direction that is reduced from the movement distance of the + X axis, that is, in the -X axis direction. The first and second motor drivers 10 and 12 and the first and second steering drivers 18 and 20 are controlled (step S25).

When the X-axis deviation distance is determined to be a deviation distance in the -X axis direction, the driving controller 22 corrects and moves the deviation distance in the direction increased from the movement distance of the -X axis, that is, in the + X axis direction. The first and second motor drivers 10 and 12 and the first and second steering drivers 18 and 20 are controlled (step S26).

On the other hand, in the determination result of the step S21, the driving controller 22 determines that the moving direction of the robot is a straight running in the X-axis direction instead of the Y-axis direction, the laser sensing unit 30 and the movement distance calculation processing unit ( In 32), the traveling direction and the moving distance of the robot are acquired by the laser light reflected from the traveling road surface (step S27).

The driving controller 22 compares the driving detection data including the driving direction and the movement distance data from the movement distance calculating processor 32 with the driving control value while the robot moves straight in the X-axis direction. It is determined whether the separation distance in the axial direction exceeds a preset separation setting value (step S28).

As a result of the determination, when it is determined that the departure distance in the Y-axis direction exceeds a preset departure setting value, the driving controller 22 determines whether the departure distance is a departure to the + Y axis (step S29).

The driving controller 22 determines that the Y-axis deviation distance is a deviation distance in the + Y-axis direction, and corrects the movement by a deviation distance in a direction that decreases from the movement distance of the + Y-axis, that is, in the -Y-axis direction. The first and second motor drivers 10 and 12 and the first and second steering drivers 18 and 20 are controlled (step S30).

The driving controller 22 determines that the Y-axis deviation distance is a deviation distance in the -Y axis direction, and corrects the movement by a deviation distance in a direction increased from the movement distance of the -Y axis, that is, in the + X axis direction. The first and second motor drivers 10 and 12 and the first and second steering drivers 18 and 20 are controlled (step S31).

Then, the driving controller 22 determines whether the correction for the movement distance error of the robot is completed (step S32), and if it is determined that the correction is not completed, proceed with its own error processing or retry the error correction. (Step S33).

While specific embodiments of the present invention have been described and illustrated above, it will be apparent that the present invention may be embodied in various modifications by those skilled in the art. Such modified embodiments should not be understood individually from the technical spirit or the prospect of the present invention, but should fall within the claims appended to the present invention.

1 is a view showing the overall configuration for the traveling control system of a robot according to the present invention,

FIG. 2 is a diagram illustrating a detailed configuration of a laser sensing unit and a movement distance calculating processor of the present invention shown in FIG. 1;

3 is a view showing that the driving control of the robot is performed based on the X-axis and the Y-axis according to the present invention;

FIG. 4 is a diagram for exemplarily describing an operation of correcting a direction and a distance deviated from a normal track when the robot travels straight according to a preferred embodiment of the present invention; FIG.

5 is a flowchart illustrating a slip driving detection and a slip avoiding operation of the robot in the driving control method of the robot according to the present invention;

6 is a flowchart illustrating an operation of correcting a departure direction and a distance in a straight running state of the robot in the driving control method of the robot according to the present invention.

<Explanation of symbols for the main parts of the drawings>

2, 4: wheel, 6, 8: motor,

10, 12: motor drive, 14, 16: steering mechanism,

18, 20: steering drive unit, 22: driving control unit,

24: key input, 26: wireless communication module,

28: external input port, 30: laser sensing unit,

32: Travel distance calculation processing unit.

Claims (13)

In the traveling control system of a robot running by rotational driving of a wheel, Light sensing means for irradiating light onto the road surface on which the robot travels and receiving and reflecting the reflected light; A movement distance calculating means for comparing and analyzing an optical signal difference of the reflected light sensed by the optical sensing means to detect a movement direction and a movement distance of the robot; The driving of the wheel is controlled according to the traveling control value so that the robot reaches the desired position, the moving distance error is calculated by comparing the moving direction and the moving distance detected by the moving distance calculation processing means with the traveling control value, and the moving Traveling control means for performing drive control to correct a distance error; And And a robot driving drive means for rotating the wheels by driving control of the driving control means and rotating the wheels so that an error distance is compensated according to the driving control for error correction of the driving control means. Robotic Travel Control System. The method of claim 1, The optical signal generated by the optical sensing means is a laser control signal of the robot. The method of claim 2, The light sensing means includes a laser diode for generating laser light, a light emitting lens that transmits the laser light and irradiates a predetermined area of the road surface, and a light receiving lens that transmits the laser light reflected from the road surface and transmits the laser light to the moving distance calculation processing means. Travel control system for a robot, characterized in that configured to include. The method of claim 1, The moving distance calculating processing means includes: an image pickup sensor for picking up the reflected light from the light sensing means on a frame-by-frame basis to generate an image signal, and a signal amplifier for amplifying the image signal picked up by the image pickup sensor; An analog-to-digital converter for digitally converting the signal amplified image signal, and a moving distance calculating unit for comparing the digitally converted image data, respectively, and calculates the moving direction and the moving distance according to the image difference. Control system. The method of claim 1, And the driving control means performs drive control to compensate for the error distance if the moving distance detected by the moving distance calculation processing means is smaller than the moving distance of the driving control value. The method of claim 1, The driving control means for driving control to compensate for the error distance when the movement direction and the movement distance detected by the movement distance calculation processing means deviated by more than a set value from the straight traveling direction and distance to the destination based on the X axis and the Y axis. Travel control system of the robot, characterized in that. The method of claim 6, The traveling control means accumulates the deviation distance value calculated by comparing the movement direction and the movement distance detected by the movement distance calculation processing means with the traveling control value, and when the accumulated departure distance value is equal to or more than the set distance, Driving control system of the robot, characterized in that for driving control to compensate. In the traveling control method of the robot running by the rotation drive of the wheel, A first step of moving the robot by controlling the driving of the wheel according to the traveling control value so that the traveling control means of the robot reaches a desired position; A second step of detecting a moving direction and a moving distance of the robot by receiving light reflected by irradiating light onto a road surface on which the robot travels in the moving state of the robot and comparing and analyzing a difference of optical signals of the reflected light; A third step of calculating a travel distance error by comparing the travel direction and the travel distance detected by the optical signal with the travel control value by the travel control means; And And a fourth step of rotationally driving the wheels to compensate for the error distance to correct the calculated movement distance error by the driving control means. The method of claim 8, In the second step, the traveling signal control method of the robot, characterized in that the optical signal irradiated and reflected on the road surface is a laser optical signal. The method of claim 8, The second step may include generating image signals by capturing the reflected light frame by frame; Amplifying and digitally converting each of the image signals; And comparing the digitally converted image data with each other to calculate a moving direction and a moving distance according to the image difference. The method of claim 8, In the fourth step, the driving control means for driving control to compensate for the error distance if the movement distance detected in the optical signal is less than the movement distance of the driving control value. The method of claim 8, In the fourth step, the driving control means compensates for the error distance if the moving direction and the moving distance detected from the optical signal deviate by more than a set value from the straight traveling direction and the distance to the destination based on the X and Y axes. Driving control method of the robot, characterized in that the drive control. The method of claim 12, In the fourth step, the traveling control means accumulates the deviation distance value calculated by comparing the movement direction and the movement distance detected from the optical signal with the driving control value, and if the accumulated deviation distance value becomes abnormal, Driving control method of the robot, characterized in that for driving control to compensate for the error distance.

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