JPH08150582A - Mobile robot travelling system - Google Patents

Abstract

PURPOSE: To eliminate tape setting construction of a travelling route by furnishing a control device with a signal transmission part to transmit a control signal to a mobile robot and a control and computation part and setting the control device in a periphery of a travelling zone. CONSTITUTION: An optical system 13 of first and second optical devices 4, 5 is made to scan in the direction of a mobile robot 1 on which a reflecting target 8 is respectively placed. When reflected light quantity becomes the maximum, a value of a rotary encoder 15 of the first and second optical devices 4, 5 is read, and the value is made standard angles θ01 , θ02 . A position P3 of the mobile robot 1 is found by a trigonometrical survey from both angles θ1 , θ2 of a distance L and a bottom a base between setting points P1 , P2 of the first and second optical devices 4, 5. This positional data is compared with a standard travelling rout previously memorized in a built in memory, and a data showing a travelling direction which the mobile robot is to take is input to a signal transmission part 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile robot traveling system, and more particularly to a system for remotely controlling the traveling direction of a mobile robot while measuring the coordinate position of the mobile robot using a laser.

[0002]

2. Description of the Related Art In a conventional mobile robot traveling system for transportation, as shown in FIG. 8, a tape 2 attached to a floor surface of a moving zone of a mobile robot 1 by a CCD camera 3 is used. It was to recognize and control the traveling device in that direction. Therefore, when changing the traveling route or setting a new route, tape replacement work is required, and even if a manned transport vehicle is used as a substitute during the construction period, the robot movement zone cannot be used because it is under construction. Have to set up a moving route for
It was very inconvenient. Furthermore, if an alternative route cannot be established, the factory equipment may have to be stopped. The present invention has been made in view of such circumstances, and an object thereof is to eliminate the need for tape installation work on a traveling route.

[0003]

[Means for Solving the Problems]

(1) The invention of claim 1 includes a mobile robot, and first and second mobile robots.
A mobile robot traveling system including an optical device and a control device. The mobile robot controls a signal receiving unit that receives a control signal sent from a control device, a reflection target that reflects the laser light emitted from the first and second optical devices, a traveling device, and each of these units. And a control unit.

The first and second optical devices include an optical system having a light projector for irradiating laser light and a light receiver for receiving and detecting laser light reflected by a reflection target, and a motor for rotationally driving the optical system. A rotary encoder that detects the rotation angle of the optical system is provided, and the rotary encoder is installed at different positions around the traveling zone of the mobile robot. The control device includes a signal transmission unit that transmits a control signal to the mobile robot and a control / calculation unit, and is installed in the vicinity of the traveling zone, and the control / calculation unit is a motor of each of the first and second optical devices. The optical axis of each optical system when the output of each optical receiver is maximized is formed by a reference line (a straight line connecting the first and second optical devices). angle theta _1, the theta ₂ calculated from the output of the rotary encoder, their angular theta _1, theta
The coordinate position of the mobile robot is calculated by triangulation from ₂ and the length L of the reference line, and the position data is compared with the reference travel route stored in advance in the built-in memory to determine the travel direction that the mobile robot should take. The data shown is input to the signal transmission unit.

(2) In the invention of claim 2, in the above (1), one end of the optical system of the first and second optical devices is released,
It has an external cylinder with the other end closed, and a projector and a light receiver are arranged at the axial center positions of the open end and the closed end, respectively, and receives the reflected light from the mobile robot that enters the open end in the middle of the external cylinder. There is a lens that focuses light on the vessel. (3) In the invention of claim 3, in the above (1), the signal transmitting unit of the control device is a wireless transmitter and the signal receiving unit of the mobile robot is a wireless receiver.

(4) In the invention of claim 4, in the above (1), the motors of the first and second optical devices are pulse motors. (5) In the invention of claim 5, in the above (1), the optical system of the first and second optical devices is directed from the first (or second) optical device toward the second (or first) optical device. Each has a reflection plate that reflects the emitted laser light to the first (or second) optical device.

(6) In the invention of claim 6, in the above-mentioned (5), the control device controls the motor of the first optical device to irradiate the second optical device with laser light, and the second optical device. The motor is controlled so that the reflection plate faces the first optical device, and the angle output θ ₀₁ of the rotary encoder when the reflected light of the reflection plate is received by the first optical device is set as the angle reference value of the first optical system. Similarly, the angle output θ of the rotary encoder when the laser light is emitted from the second optical device to the first optical device and the laser light reflected by the reflecting plate is received.
₀₂ is the angle reference value of the second optical device.

(7) In the invention of claim 7, in the above (2) and (5), the reflector is directed to the outer surface of the closed end of the outer cylinder of the first and second optical devices in the direction opposite to the open end. Installed.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mobile robot traveling system according to the present invention comprises a mobile robot 1, first and second optical devices 4 and 5, and a control device 6 as shown in FIG. Mobile robot 1
Includes a signal receiving unit 7 that receives a control signal transmitted from the control device 6, a reflection target 8 that reflects the laser light emitted from the first and second optical devices 4 and 5, a traveling device 9, and these units. A control unit 10 for controlling is provided.

Each of the first and second optical devices 4 and 5 has an optical system 1 having a light projector 11 for irradiating laser light and a light receiver 12 for receiving and detecting the laser light reflected by the reflecting target 8.
3, a motor 14 for rotationally driving the optical system 13 thereof, and a rotary encoder 15 for detecting the rotation angle of the optical system 13, and they are installed around the travel zone 16 at points apart from each other to some extent. In FIG. 3, they are installed at adjacent corners P ₁ and P ₂ of the rectangular traveling zone.

The control device 6 is provided with a signal transmission unit 21 for transmitting a control signal to the mobile robot 1 and a control / calculation unit 22. The control / arithmetic unit 22 controls the motors 14 of the first and second optical devices 4 and 5 to scan the angle of each optical system 13 and each optical system when the output of each light receiver 12 becomes maximum. The angles θ ₁ and θ ₂ between the optical axis 24 (see FIG. 2) and the reference line 24 (a straight line connecting the first and second optical devices; see FIGS. 3 and 4) are output from the rotary encoders 15. Based on the angles θ ₁ and θ ₂ and the length L of the reference line 24, the coordinate position P ₃ (x, y) of the mobile robot 1 is calculated according to the principle of triangulation. Then, the position data is compared with the reference traveling route stored in advance in the built-in memory, and the data for instructing the traveling direction of the mobile robot 1 is input to the signal transmitting unit 21.

In the example shown in FIG. 1, the signal transmitting unit 21 and the signal receiving unit 7 are composed of a wireless transmitter and a wireless receiver which are relatively inexpensive to obtain. However, other means such as an optical transmitter or an optical receiver can be used. FIG. 2 shows the structure of the first and second optical devices 4 and 5. The optical system 13 has an outer cylinder 31 whose one end is open and whose other end is closed, and the projector 11 and the light receiver 12 are arranged at the axial center positions of the open end and the closed end, respectively, and in the middle of the outer cylinder. A lens 32 for condensing the reflected light Lb incident on the open end from the mobile robot on the light receiver 12 is arranged.

In this example, the reflection plate 37 is attached to the outer surface of the closed end of the outer cylinder 31 in the direction opposite to the open end. As will be described later, the reflection plate 37 is a projection light (laser light) L radiated toward itself from the opposing optical device of the opposite side.
It is used to reflect a to the optical system 13 of the other side optical device, align the optical axes 24 of each other, and set their directions as the respective reference directions.

As the motor 14, it is desirable to use a pulse motor (stepping motor or the like) capable of controlling the rotation angle of the motor shaft with high accuracy. The control device 6 may be housed in the housing of the first or second optical device. Next, a method of detecting the coordinate position of the mobile robot by triangulation will be described in detail. (STEP1) The first and second optical devices 4 and 5 are opposed to each other as shown in FIG. The laser light projected from the first optical device 4 is reflected by the reflection plate 37 of the second optical device 5 and is focused on the light receiver 12 of the first optical device 4. At this time, the amount of reflected light is maximized if the two optical devices face each other accurately. Therefore, the optical system 13 of the second optical device 5 is rotated so that the peak position of the amount of reflected light is searched for. When the amount of reflected light becomes maximum, the value (angle) of the rotary encoder 15 of the first and second optical devices 4 and 5 is read, and the value is read as the reference angle θ.
₀₁ and θ ₀₂ .

(STEP2) As shown in FIG.
1 and the optical system 13 of the second optical device, respectively.
Scanning in the direction of the mobile robot 1 on which
Let The laser light projected from the first optical device 4 is
The light is reflected by the irradiation target 8 and received by the first optical device 4.
It is focused on the container 12. When the amount of reflected light is scanned
As shown in FIG. 6, it takes a peak value at a certain position. then
The rotary encoder 15 reading of₁’
θ₁′ −θ₀₁From the reference angle by finding
It can be seen whether the optical system 13 is oriented in the direction of. This value
And θ₁= Θ₁′ −θ ₀₁, Then θ₁Is already mentioned
1 the optical axis 24 of the optical system 13 of the optical device 4 and the reference line 24
Angle, which is the reference angle θ of the optical system 13.₀₁Rotation angle from
Is. The optical system 1 is similarly used for the second optical device 5.
Reference angle θ of 3₀₂Rotation angle from₂Ask for.

(STEP 3) First and second optical devices 4,
The distance L between the five installation points P ₁ and P ₂ is known. As shown in FIG. 7, a triangle connecting the positions P ₃ and P ₁ , P _{2 of the} mobile robot 1 is a triangle having a base L and both angles θ ₁ and θ ₂ of the base. Therefore, the position P ₃ (x, y) of the mobile robot is obtained from the principle of triangulation. Equation (1) is established from the triangle formula. However, a is the distance between P _{2 and} P ₃ , and b is the distance between P _{1 and} P ₃ .

A / sin θ ₁ = b / sin θ ₂ = L / sin θ ₃ (1) From FIG. 7, b ₁ = b cos θ ₁ = L × (sin θ ₂ / sin θ ₃ ) × cos θ ₁ ... (2) sin θ ₃ = sin {180 − (θ ₁ + θ ₂ )} = sin 180 cos (θ ₁ + θ ₂ ) −cos 180 sin (θ ₁ + θ ₂ ) = sin (θ ₁ + θ ₂ ) = sin θ ₁ cos θ ₂ + cosθ ₁ sinθ ₂ (3) Substituting (3) into (2), b ₁ = L sinθ ₂ cosθ ₁ / (sinθ ₁ cosθ ₂ + cosθ ₁ sinθ ₂ ) = L tanθ ₂ / (tanθ ₁ + tan θ ₂ ) = x (4) b ₂ = b sin θ ₁ = L × (sin θ ₂ / sin θ ₃ ) × sin θ ₁ (5) Substituting (3) into (5) b ₂ = L sin θ ₂ sin θ ₁ / (sin θ ₁ cos θ ₂ + cos θ ₁ sin θ ₂ ) = L tan θ ₁ tan θ ₂ / (tan θ ₁ + tan θ ₂ ) = y The position P ₃ (x, y) of the robot is known.

[0018]

According to the present invention, for example, the position of the mobile robot 1 is measured every one second, and a predetermined course is moved by giving an instruction as to which direction the mobile robot 1 should face. be able to. Therefore, it is not necessary to construct the guide tape on the floor as in the conventional case.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

2A and 2B are a sectional view and a perspective view of the first and second optical devices of FIG. 1, respectively.

FIG. 3 is a perspective view showing an arrangement of a main part of FIG. 1 inside and outside a traveling zone.

4 is an optical system 13 of the first and second optical devices 4 and 5 of FIG.
6 is a perspective view for explaining angles θ ₁ and θ ₂ formed by the reference line 24 and the optical axis 24 of each optical system when the is oriented toward the mobile robot 1. FIG.

5 is a front view of the optical system 13 of the first optical device 4 and a back view of the optical system 13 of the second optical device 5 of FIG. The principle side view which shows the reflected state.

6 is an optical system 13 of the first and second optical devices 4 and 5 of FIG.
6 is a graph showing changes in the detection output when the light receiver 12 detects the reflected light from the mobile robot 1 by scanning the angle.

FIG. 7 defines an angle formed by each side of a triangle formed by the positions P ₁ and P _{2 of} the first and second optical devices 4 and 5 and the position P ₃ of the mobile robot 1 in the embodiment of FIG. The top view for doing.

FIG. 8 is a perspective view of a conventional mobile robot.

Claims (7)

[Claims] 1. A mobile robot traveling system comprising a mobile robot, first and second optical devices, and a control device, wherein the mobile robot receives a control signal sent from the control device. A reflection target that reflects the laser light emitted from the first and second optical devices,
A traveling device and a control unit that controls these units are provided, and the first and second optical devices include a light projector that irradiates laser light and a light receiver that receives and detects the laser light reflected by the reflection target. An optical system, a motor that rotationally drives the optical system, and a rotary encoder that detects a rotation angle of the optical system are provided, and the optical system is installed at different positions around a traveling zone of the mobile robot. The robot is provided with a signal transmission unit for transmitting a control signal to the robot and a control / calculation unit, and is installed in the vicinity of the traveling zone. The control / calculation unit controls each motor of the first and second optical devices. Angle between the optical axis of each optical system and the reference line (the straight line connecting the first and second optical devices) when the output of each optical receiver is maximized by scanning the direction of each optical system.
₁ and θ ₂ are obtained from the output of each rotary encoder, the coordinate position of the mobile robot is calculated by triangulation from the angles θ ₁ and θ ₂ and the length L of the reference line, and the position data is stored. A mobile robot traveling system, which compares the reference traveling route stored in advance in the memory of 1. to input data indicating a traveling direction of the mobile robot to the signal transmitting unit. 2. The optical system according to claim 1, wherein the optical system of the first and second optical devices has an external cylinder whose one end is open and the other end is closed, and which are located at the axial center positions of the open end and the closed end. The mobile robot running is characterized in that the light emitter and the light receiver are respectively arranged, and a lens for condensing the reflected light from the mobile robot incident on the open end to the light receiver is arranged in the middle of the outer cylinder. system. 3. The mobile robot traveling system according to claim 1, wherein the signal transmitting unit of the control device is a wireless transmitter and the signal receiving unit of the mobile robot is a wireless receiver. 4. The mobile robot traveling system according to claim 1, wherein the motors of the first and second optical devices are pulse motors. 5. The optical system according to claim 1, wherein the optical system of each of the first and second optical devices is a second (second) optical device rather than a first (or second) optical device.
A mobile robot traveling system, characterized in that each of the mobile robot traveling systems has a reflection plate that reflects the laser light emitted toward the (or first) optical device to the first (or second) optical device. 6. The control device according to claim 5, wherein the control device controls a motor of the first optical device to irradiate a laser beam toward a second optical device, and controls a motor of the second optical device to control the motor. The angle output θ ₀₁ of the rotary encoder when the reflection plate is opposed to the first optical device and the reflected light of the reflection plate is received by the first optical device is set as the angle reference value of the first optical system, and similarly, The angle output θ ₀₂ of the rotary encoder when the laser beam is emitted from the second optical device to the first optical device and the laser beam reflected by the reflector is received is used as the angle reference value of the second optical device. A characteristic mobile robot traveling system. 7. The reflecting plate according to claim 2, wherein the reflector is attached to an outer surface of the closed end of the outer cylinder of the first and second optical devices in a direction opposite to the open end. A mobile robot traveling system characterized by.