JP2019056987A - Robot carriage traveling control method of and robot - Google Patents

Abstract

To provide a technology that enables a robot to travel autonomously along an easily settable or changeable traveling route by making it easy for the traveling route of the traveling robot to be set or to be changed.SOLUTION: A robot carriage 2 comprises: a driving wheel 4; a driving motor for rotationally driving the driving wheel 4; a turnaround wheel 6; a steering motor 7 for making the turnaround wheel 6 turn around and steer; and a linear photosensor array that has light receivers that are arrayed orthogonally to the traveling direction of the carriage, facing the traveling ground surface. Reflector plates RP are sparsely arranged on the traveling ground surface of the robot carriage 2. A controller of the robot carriage 2 performs a feedback control of a steering angle θ of the turnaround wheel 6 in accordance with the amount of the control corresponding to the amount of displacement δ detected by the linear photosensor array in the orthogonal direction of the line of reflector plates RP. This enables the robot carriage 2 to travel along the traveling route, modifying its direction when it passes through the reflector plate RP.SELECTED DRAWING: Figure 6B

Description

  The present invention relates to a traveling robot that travels along a predetermined traveling route, a robot carriage adapted to transport the robot, and a method for suitably controlling the traveling of such a carriage.

  Conventionally, various robots that can move along a line or a travel route laid on the floor have been proposed (see, for example, Patent Documents 1 to 4).

Japanese Patent Laid-Open No. 6-1887032 JP-A-7-295537 JP 2002-73171 A JP 2004-277062 A

  A conventional traveling robot travels on a traveling route in which a line is painted on a traveling surface or a magnetic tape or the like is continuously laid. For this reason, in order to change the travel route or to change the travel route once set by changing the layout of the facility, work such as painting, repainting, or repainting of the lines is required, which is complicated.

  Accordingly, an object of the present invention is to provide a technique that makes it easy to set or change a travel route of a travel robot and allows the robot to travel autonomously along the travel route.

  In order to solve the above-described problems, the present invention provides a robot carriage that can travel along a traveling path, and includes a propulsion wheel, a propulsion motor that rotationally drives the propulsion wheel, direction changing means, and the propulsion motor. And a control device that controls the traveling of the cart by controlling the direction changing means, and a line-shaped optical sensor that has a light receiving portion on the side that is orthogonal to the traveling direction of the cart and faces the running surface. A plurality of reflectors are arranged on the travel path, the line-shaped optical sensor detects a deviation amount in the width direction of the reflector, and the control device detects the deviation amount. The direction changing means is controlled by controlling the direction changing means according to the control amount, and the direction of the cart is corrected. An IC tag is provided at any one or a plurality of check positions of the travel route, and the control device But The current position of the carriage, the is configured to calibrate the check position based on the identification information received from the IC tag, a carriage robot.

  In the robot carriage configured as described above, a route map including arrangement information of the reflecting plate is stored in the storage unit of the control device, and the route map is calculated based on the measured travel distance of the cart. It is preferable that the current position of the cart is recognized by referring to.

  Further, in the robot cart having the above-described configuration, the control device is configured to measure the travel distance of the cart by counting the number of passing through the reflecting plate detected by the line-shaped optical sensor. Is preferred.

  In the robot cart having the above-described configuration, the control device may be configured to measure a travel distance of the cart by counting a rotation amount of the propulsion wheel.

  Further, in the robot carriage having the above-described configuration, a travel plan from the starting position to the target position can be set in the storage unit of the control device, and the control device can be set according to the set travel plan. It is preferable to be configured to control the traveling of the cart.

  The present invention is also a traveling robot in which a robot body is mounted on the robot carriage having the above-described configuration.

  The present invention is also a travel control method for controlling the travel of a robot along a travel route, wherein a plurality of reflectors are arranged on the travel route, and the robot includes a direction changing means, A line-shaped optical sensor having a light receiving portion on a side orthogonal to the traveling direction and facing the traveling surface, and a control device, the line-shaped optical sensor having a displacement amount in the width direction of the reflecting plate. A step of detecting, a step of correcting the direction of the cart by controlling the direction changing means by a control amount corresponding to the detected deviation amount, and the control device recognizes Calibrating the current position of the cart to a check position based on identification information received from an IC tag provided at any one or a plurality of check positions on the travel route. .

  According to the present invention, the robot carriage can travel autonomously while automatically correcting the direction along a simple traveling route in which the reflector is disposed on the traveling surface. In addition, the travel route can be easily changed simply by changing the arrangement of the reflectors.

It is a side view for demonstrating the outline | summary of a traveling robot. It is a block diagram which shows schematic structure of the trolley | bogie for robots. It is a rear view of the cart for robots. It is a table | surface which illustrates the relationship between the output value of a line-shaped optical sensor, and the deviation | shift amount of a reflecting plate. It is a block diagram which illustrates the control circuit with which the cart for robots is equipped. It is a figure for demonstrating operation | movement of the cart for robots by one Embodiment. It is a figure for further explaining operation of the cart for robots shown in Drawing 6A. It is a figure which illustrates the route map memorize | stored in the memory | storage means of the cart for robots. It is a figure for demonstrating the operation | movement with which the cart for robots carries out autonomous traveling with reference to the route map of FIG. It is a figure for demonstrating operation | movement of the cart for robots by other embodiment. It is a figure for demonstrating further operation | movement of the cart for robots shown to FIG. 9A.

  Preferred embodiments of the present invention will be described below with reference to the drawings. A traveling robot 1 illustrated in FIG. 1 includes a robot carriage 2 as a lower traveling body and a robot body 3 mounted on the robot carriage 2. As the robot body 3, various types of robots can be arbitrarily selected according to the purpose and function, such as a human-type guidance robot, an animal-type pet robot, a bucket-type or container-type transport robot. The robot carriage 2 that transports the robot body 3 can move along a traveling route arbitrarily determined in advance on the floor surface (traveling surface) FS of the facility. In the present embodiment, as an index when the robot carriage 2 travels, the travel path along which the robot carriage 2 travels is set by disposing the reflector RP intermittently or scattered on the floor surface FS. The The reflector RP is square or rectangular, and two parallel sides are arranged in the direction in which the travel route extends. In order to make it easy to change the travel route, it is preferable that the reflector RP is disposed on the floor surface FS by means of easy attachment / detachment such as adhesion.

  FIG. 2 is a block diagram illustrating a schematic configuration of the robot carriage 2. The robot carriage 2 has two propulsion wheels 4 and 4, a propulsion motor 5 that rotationally drives each propulsion wheel 4, a direction changing wheel 6, and a steering that turns and steers the direction changing wheel 6 as a traveling drive system. And a motor 7. In the present embodiment, the direction changing wheel 6 and the steering motor 7 constitute a direction changing means for the robot carriage 2.

  The propulsion wheel 4 is a wheel for moving the robot carriage 2 forward or backward. The two propulsion wheels 4 and 4 have the same diameter, and are provided in a pair of left and right on the side of the robot carriage 2 so as to be coaxial and parallel to each other. However, a slight camber angle may be set on the propulsion wheel 4 in order to improve running stability.

  The propulsion motor 5 can be a rotary stepping motor, for example, and its drive shaft is connected to the shaft of the propulsion wheel 4. The left and right propulsion wheels 4 and 4 are driven to rotate independently by respective propulsion motors 5 and 5. Moreover, the structure by which the torque of the propulsion motor 5 is transmitted to the propulsion wheel 4 via a reduction gear (not shown) may be employed. An encoder 11 is attached to the shaft of the propulsion wheel 4, and the rotation amount of the propulsion wheel 4 is detected by the encoder 11.

  The direction change wheel 6 is a wheel for moving the robot carriage 2 straight and changing the direction of the carriage 2 according to the steering angle (turning angle). The direction change wheel 6 is pivotably provided at the center of the front part of the main body of the robot carriage 2. The steering motor 7 can be, for example, a direct-acting stepping motor, and is configured to control the steering angle (turning angle) of the direction change wheel 6 via an appropriate link mechanism 12.

  The robot carriage 2 includes a controller 20 that is a control device such as a microcomputer and a line-shaped optical sensor 30 as a control system related to traveling.

  The controller 20 has a microcomputer chip including a CPU, a ROM, a RAM, a communication interface, and the like, and a logic circuit, a drive circuit, and the like necessary for running and monitoring the robot are mounted on a substrate. The CPU implements various control functions described below by executing arithmetic processing according to the program code stored in advance in the ROM. As will be described later, the controller 20 controls driving of the propulsion motor 5 and the steering motor 7 on the basis of a traveling condition parameter or the like set in advance by an external remote controller or the like. Thereby, the traveling of the robot carriage 2 is autonomously controlled.

  FIG. 3 is a rear view of the robot carriage 2 as viewed from the rear. The line-shaped optical sensor 30 provided at the bottom of the main body of the carriage 2 has a plurality (eight in the embodiment) of optical sensor elements D1 to D8 each including a pair of a light emitting unit and a light receiving unit. Each of the optical sensor elements D1 to D8 is arranged in a direction orthogonal to the traveling direction of the robot carriage 2 and has a light receiving portion on the side facing the floor surface FS that is the traveling surface. With such a line-shaped optical sensor 30, it is possible to detect a relative position in the width direction of the reflector RP with respect to the traveling center line of the carriage 2 (an offset displacement amount, or simply referred to as “deviation amount”). . Here, the “width direction” refers to a direction orthogonal to the traveling direction (forward and backward) of the robot carriage 2.

  Each of the optical sensor elements D1 to D8 emits sensing light having a certain intensity with the light emitting portion directed downward, and outputs an “H” level signal if the intensity of the reflected light received by the light receiving portion is equal to or greater than a predetermined value. Output (ON state). That is, the floor surface FS and the reflecting plate RP are identified by the difference in light reflectance. Therefore, in order to reliably detect the reflecting plate RP, it is preferable to use a glossy plate made of, for example, an aluminum alloy having a larger reflectance than the floor surface FS as the reflecting plate RP.

  Note that the sensing light emitted by the line-shaped optical sensor 30 may be either diffused light or laser light. The sensing light may be light having any frequency from visible light to infrared light. However, it is known that the metal plate has a significantly lower infrared emissivity (absorption rate) than the floor surface FS made of non-metal. Therefore, when an aluminum alloy is used for the reflector RP, the metal plate It is preferable to use an infrared light sensor that causes a difference in reflectance between the non-metal and the non-metal for the line-shaped light sensor 30.

  More specifically, the line-shaped optical sensor 30 includes optical sensor element groups D1 to D4 that detect the left part of the reflecting plate RP, and optical sensor element groups D5 to D8 that detect the right part of the reflecting plate RP. Composed. Here, FIG. 4 illustrates the relationship between the output values D1 to D8 of the line-shaped optical sensor 30 and the deviation amount δ of the reflecting plate RP with respect to the traveling direction center of the robot carriage 2. As shown in FIG. 3, when the reflector RP is located at a specified position that is the center of the robot carriage 2, only the center optical sensor elements D 4 and D 5 detect the left and right ends of the reflector RP and “ H ”level. For example, as the amount of the robot carriage 2 deviating to the left from the reflector RP increases (the displacement amount δ of the reflector RP is +1 to +3), the optical sensor element groups D5 to D8 that detect the right part of the reflector RP The number of “H” levels increases. Conversely, as the amount of the robot carriage 2 deviating to the right from the reflector RP increases (the displacement amount δ of the reflector RP is −1 to −3), the optical sensor element group that detects the left part of the reflector RP. The number at which D1 to D4 become “H” level increases. Utilizing such characteristics, the controller 20 uses the output value of the line-shaped optical sensor 30 (hereinafter also referred to as digital values D1 to D8) to shift the reflector RP, in other words, the robot carriage. The amount 2 deviates from the predetermined travel route can be grasped.

  The block diagram of FIG. 5 is an example of a circuit for automatically correcting and controlling the traveling of the traveling robot 1 along a traveling route in which the reflector RP is intermittently disposed. This control circuit is mounted on the controller 20 of the robot carriage 2 and determines the amount of deviation δ in the width direction of the reflector RP detected by the line-shaped optical sensor 30 as the steering angle (turning angle) θ of the direction change wheel 6. A closed-loop circuit that feeds back is configured.

  The configuration of this control circuit will be described more specifically. In the block diagram of FIG. 5, the inverting input terminal (− terminal) of the operational amplifier 201 has a DA decoder (DAD: Digital Analog Decoder) 202 indicating the amount of deviation δ of the reflector RP detected by the line-shaped optical sensor 30. The deviation amount signal output from is input. The DA decoder 202 is a conversion circuit that decodes the output values D1 to D8 of the line-shaped photosensor 30 into deviation amount data and outputs, for example, the voltage value shown in FIG. 4 as an analog signal as the deviation amount signal.

  The non-inverting input terminal (+ terminal) of the operational amplifier 201 receives a voltage value indicating the target deviation amount, that is, 0 mV. This target voltage value may be obtained from the DA decoder 203 having the same characteristics as the DA decoder 202. In this case, as shown in FIG. 5, the inputs corresponding to D4 and D5 of the DA decoder 203 are set to “H” level, and the inputs corresponding to the other D1 to D3 and D6 to D8 are set to “L” level. Good.

  Thereby, the operational amplifier 201 can output a control signal of a control amount θ proportional to the deviation amount δ of the reflector RP and steering the direction change wheel 6 in the reverse direction to the steering motor 7. The values of the input resistance R1 and the feedback resistance R2 that determine the closed loop gain of the travel correction control circuit are set so that the travel state does not vibrate according to the interval of the reflector RP, the speed of the robot carriage 2, and the like. Set as appropriate.

  According to such a travel correction control circuit, the steering angle θ of the direction change wheel 6 is feedback-controlled so that the deviation amount δ of the reflector RP with respect to the travel center line of the robot carriage 2 becomes zero. Therefore, the robot carriage 2 can autonomously travel along the traveling route with the reflector RP, for example, as shown in FIG. Further, even if the robot carriage 2 is deviated from the travel route, as shown in FIG. 6B, the robot cart 2 can travel along the correct travel route while correcting the direction when passing through the reflector RP. .

  The control circuit also has a function of measuring the travel distance of the robot carriage 2 by counting the number of passing through the reflector RP detected by the line-shaped optical sensor 30. For example, in the block diagram of FIG. 5, the output values D1 to D8 of the line-shaped photosensor 30 are input to the low-active AND circuit 204. According to this configuration, since any one of the sensor output values D1 to D8 is at “H” level at the position where the line-shaped optical sensor 30 detects the reflecting plate RP, the AND circuit 204 outputs an “L” level signal. Output. On the other hand, at the position where the line-shaped optical sensor 30 is between the two reflectors RP, the sensor output values D1 to D8 are all at the “L” level, and the AND circuit 204 outputs an “H” level signal. . Therefore, the controller 20 can grasp the number of the reflecting plates RP that the robot carriage 2 has passed by counting the output change of the AND circuit 204 by the counter 24. Then, the controller 20 multiplies the robot carriage 2 by multiplying the total length of the interval between the reflectors RP and the dimension of the reflector RP in the path direction by the number of the reflectors RP that have passed. The distance can be measured.

  The controller 20 may measure the travel distance of the robot carriage 2 from the accumulated rotation amount of the propulsion wheel 4 counted through the encoder 11 attached to the propulsion wheel 4. Further, the travel distance of the robot carriage 2 may be measured by adding the rotation amount of the propulsion wheel 4 to the number of the reflecting plates RP that have passed.

  Further, the storage means (including EPROM, SRAM, smart media, etc.) of the controller 20 may store route map data as shown in FIG. 7, for example. In this route map, the travel route C, the arrangement coordinates of the reflector RP, and the like are described. The controller 20 can recognize the current position of the cart 2 by referring to the route map one by one every time the reflector plate RP is passed, for example, based on the travel distance of the robot cart 2 measured by the method described above. it can.

  Alternatively, one or a plurality of points on the travel route C may be arbitrarily determined as a check position, and the IC tag CP may be provided on the check position or the reflector RP at the check position. For example, a position where the traveling robot 1 frequently goes back and forth is preferably determined as a check position. Identification information (position information) indicating the coordinates of the check position is recorded in the IC tag CP. When the traveling robot 1 reaches the check position, the controller 20 receives identification information (position information of the check position) from the IC tag CP at that position. And the controller 20 can calibrate the present position of the said trolley | bogie 2 recognized from the passage number of the reflecting plate RP and / or the count value of the encoder 11 to the check position based on the identification information received from the IC tag CP.

  When the robot carriage 2 travels on a route without the reflector RP, the output values D1 to D8 of the line-shaped optical sensor 30 are all at the “L” level, and feedback control cannot be performed. However, in that case, it is preferable to maintain the sensor output values D1 to D8 indicating the amount of deflection of the reflector RP that has passed last in order to maintain smooth running. For this purpose, the control circuit illustrated in FIG. 5 is provided with a D flip-flop 205 that holds the latest sensor output values D1 to D8 on the input side of the DA decoder 202. That is, according to this circuit, when the line-shaped optical sensor 30 detects the edge of the reflecting plate RP and all the sensor output values D1 to D8 are at the “L” level, the gate circuit 206 is turned off by the output of the AND circuit 204. The supply of the timing signal CK to the D flip-flop 205 is stopped. As a result, the latest sensor output values D1 to D8 are held in the D flip-flop 205.

  As shown in FIG. 2, the robot carriage 2 includes an obstacle sensor, a human detection sensor, and the like that are optionally provided for input / output of control signals that the controller 20 communicates with the robot body 3 and collision avoidance. An I / O port 21 for inputting a signal from the terminal may be provided. In addition, a remote control receiving unit 22 for receiving a signal from an external remote control operating device, an RF receiving unit 23 for receiving position information from an IC tag arranged at a predetermined check position, and the like are optionally provided. Can do.

Further, the robot carriage 2 can travel unmanned under the control of the controller 20 according to a travel plan from the starting position to the target position. For example, when the user inputs the position number and coordinate information of the target position where the traveling robot 1 is to arrive by using the remote control device, the controller 20 refers to the route map stored in the storage means, for example, the current position. It is possible to automatically create a travel plan from there to the target position. For example, in the example of FIG. 8, the following program code is created by the controller 20 as a travel plan from the starting position (X2Y26) to the target position (X32Y29) of the traveling robot 1 (robot carriage 2).
YP8; TL90; XP30; TL90; YN5:
Here, “YP8” means a command for moving the carriage 2 by 8 frames in the YP direction, “TL90” means a command for turning the carriage 2 left by 90 degrees, and “XP30” means that the carriage 2 is moved to XP. This means a command for moving 30 frames in the direction, and “YN5” means a command for moving the carriage 2 forward in the YN direction by 5 frames. Here, the “frame” is a number used when counting the number of reflectors RP that pass therethrough.
Then, the controller 20 can accurately move the traveling robot 1 along the predetermined traveling route C from the starting position to the target position by traveling the robot carriage 2 according to the created program code.

  A plurality of target positions to which the traveling robot 1 is moved may be set in the order of arrival, or may be set so that the robot reciprocates between the two target positions. In addition, parameters such as departure time (or arrival time) at each position and travel speed can be set by a method such as operation input by a remote controller or direct writing in a storage device of the controller 20.

  Thus, the traveling robot 1 having the robot carriage 2 as a traveling body can autonomously and reliably move to the target position on the traveling path C. In addition, the travel route can be easily set only by arranging the reflector RP on the floor surface FS. Further, the travel route can be easily changed in accordance with the layout change of the facility where the traveling robot 1 operates.

  For example, as shown in FIGS. 9A and 9B, the robot carriage 2 includes direction changing means that can change direction and turn 180 degrees on the spot by the rotational speed difference Δω between the two-axis propulsion wheels 4 and 4. It may be a thing. In that case, the controller 20 of the robot carriage 2 has a rotational speed difference Δω between the left and right propulsion wheels 4 and 4 according to the deflection amount δ of the reflector RP detected by the line-shaped optical sensor 30. Each propulsion motor 5 is feedback-controlled. Thereby, like the above-mentioned embodiment, when the robot carriage 2 passes through the reflector RP, the robot carriage 2 can travel along the travel route while automatically correcting the direction.

DESCRIPTION OF SYMBOLS 1 Traveling robot 2 Robot carriage 3 Robot main body 4 Propulsion wheel 5 Propulsion motor 6 Direction changing wheel 7 Steering motor 11 Encoder 12 Link mechanism 20 Controller 21 I / O port 22 Remote control reception unit 23 RF reception unit 24 Counter 30 Line-shaped optical sensor 201 Operational amplifiers 202, 203 DA decoder 204 AND circuit 205 D flip-flop 206 Gate circuit C Travel path RP Reflector FS Floor CP IC tag δ Reflector deflection amount θ Steering angle (turning angle) of direction change wheel
Δω Propulsion wheel rotation speed difference

Claims (7)

A robot cart that can travel along a travel route,
A propulsion wheel,
A propulsion motor that rotationally drives the propulsion wheel;
Direction change means,
A control device that controls the traveling of the carriage by controlling the propulsion motor and the direction changing means;
A line-shaped optical sensor having a light receiving portion on a side orthogonal to the traveling direction of the carriage and facing the traveling surface,
A plurality of reflectors are arranged on the travel route,
The line-shaped optical sensor detects the amount of deviation in the width direction of the reflector,
The control device is configured to correct the direction of the carriage by controlling the direction changing means with a control amount corresponding to the detected deviation amount,
An IC tag is provided at any one or a plurality of check positions of the travel route,
A robot cart configured to calibrate the recognized current position of the cart to a check position based on identification information received from the IC tag. In the storage unit of the control device, a route map including arrangement information of the reflector is stored,
The robot cart according to claim 1, wherein the control device is configured to recognize a current position of the cart by referring to the route map based on the measured travel distance of the cart.   3. The robot cart according to claim 1, wherein the control device is configured to measure a traveling distance of the cart by counting the number of passing through the reflecting plate detected by the line-shaped optical sensor. .   The cart for robots according to any one of claims 1 to 3, wherein the control device is configured to measure a travel distance of the cart by counting a rotation amount of the propulsion wheel. In the storage means of the control device, a travel plan from the starting position to the target position can be set,
The robot cart according to any one of claims 1 to 4, wherein the control device is configured to control traveling of the cart according to the set travel plan.   A traveling robot comprising a robot body mounted on the robot carriage according to any one of claims 1 to 5. A travel control method for controlling the travel of a robot along a travel route,
A plurality of reflectors are arranged on the travel route,
The robot includes direction changing means, a line-shaped optical sensor having a light receiving portion on a side orthogonal to the traveling direction of the robot and facing the traveling surface, and a control device,
The line-shaped optical sensor detecting the amount of deviation in the width direction of the reflector;
The control device correcting the direction of the carriage by controlling the direction changing means by a control amount according to the detected displacement amount; and
A step of calibrating the recognized current position of the cart to a check position based on identification information received from an IC tag provided at any one or a plurality of check positions of a travel route. Travel control method.