JPS6332613A - Photoelectric guide system for unmanned vehicle - Google Patents

Abstract

PURPOSE:To smoothly drive straight or turn right and left an unmanned vehicle at a turning point of a guide band in response to a turning command, by providing a holding circuit which fixes the outputs of a pair of right and left photoelectric transducers and a detecting circuit for maximum output. CONSTITUTION:When a turning indication shows a straight drive of an unmanned carrier, the FFs 20 and 21 are set and the fixed output values of amplifiers 10 and 11 are delivered form the sample holding circuits 14 and 15. The vehicle travels straight. When the vehicle crosses a guide band bending right and left together with the maximum output secured, the detecting circuits 12 and 13 reset the circuits 14 and 15. Then both FFs 20 and 21 are reset and a normal drive mode is reset. At the time of right turn only the FF 20 is set and the fixed output value of the amplifier 10 is delivered from the circuit 14. Thus the carrier is steered by the outputs received from the circuit 14 and the amplifier 11 and turn to the right. A maximum output detecting circuit 12 detects the output of the amplifier 10, i.e., the output of a left photoelectric transducer and then detects which crosses the left and straight guide bands and has its maximum value. Then the circuit 14 and then the FF 20 are reset. Thus a normal drive mode is reset. Then the carrier is turned left by reversing the operations done at the time of right turn.

Description

[Detailed Description of the Invention] [Industrial Application] The present invention detects reflected light from a guide strip stretched on the floor using a pair of left and right photoelectric conversion elements attached to the body of an unmanned vehicle. This invention relates to a photoelectric guidance system for unmanned vehicles that guides unmanned vehicles along a guidance zone using detection signals.

[Prior art]

Techniques related to an unmanned vehicle guidance device for guiding an unmanned vehicle along a predetermined route are conventionally disclosed in Japanese Patent Publication No. 53-26753, ``One-Vehicle Guidance Device'' and Japanese Patent Application Laid-Open No. 1983-1989.
1 Unmanned Transport Vehicle Disclosed in Publication No. 42580. However, the method disclosed in the above-mentioned Japanese Patent Publication No. 53-26753 has the disadvantage that burying the guide wire in the floor involves complicated work such as trench digging, burying the wire, backfilling, and curing. The method disclosed in Japanese Patent Application Laid-Open No. 50-42580 digitally detects the deviation of the vehicle body from the guide zone, and therefore has a problem in that the steering of the unmanned vehicle lacks smoothness.

Therefore, the applicant has previously developed and filed an application for an optical guidance system for unmanned vehicles that uses an optical guidance system that makes it easy to install a guidance belt and that allows for smooth guidance and steering of unmanned vehicles. 61
-131305).

FIG. 2 is a diagram showing an outline of the system configuration of an optical guidance device for an unmanned vehicle that was previously filed by the applicant. In the figure, reference numeral 31 indicates an induction band with good light reflection efficiency such as an aluminum plate stretched over the floor surface 32, and 33 and 34 refer to a photoelectric converter that receives reflected light from the induction band 31 and converts it into an electrical signal. 35 is a differential amplifier that takes and amplifies the difference between the outputs of the photoelectric conversion elements 33 and 34; 36 is the differential amplifier 35;
a steering angle signal generating circuit that generates and outputs a steering angle signal according to the analog output signal of 3 and 7; a steering motor that drives the steering motor 38 according to the steering angle signal from the steering angle signal generating circuit 36; A drive device, 39 is a potentiometer that detects the steering angle of the car flfh40, 41 is a travel motor, 4
2 is a travel motor drive device that drives the travel motor 41.

The reflected light from the induction band 31 is converted into an electrical signal by photoelectric conversion elements 33 and 34, and is input to the differential amplifier 35. The differential amplifier 35 takes the difference between the output signals of the photoelectric conversion elements 33 and 34, amplifies it, and outputs it to the steering angle signal generation circuit 36. The steering angle signal generation circuit 36 generates a steering angle signal according to the amount of reflected light from the differential amplifier 35 and sends the steering angle signal to the steering motor drive device 37. The steering motor drive device 37 drives the steering motor 38 according to the steering angle signal. This causes the wheels 4o to turn to the right or left. This turning amount is detected by a potentiometer 39 and fed back to the steering motor drive device 37.

When the vehicle body deviates from the guide band 31, the optical guidance system for unmanned vehicles detects the amount of deviation as a change in the amount of reflected light from the guide band 31, obtains a steering signal corresponding to the change in the amount of reflected light, and detects the amount of deviation as a change in the amount of reflected light from the guide band 31. Since the steering motor 38 is driven in accordance with the steering signal, by associating the steering signal with the steering angle and steering speed of the wheels 40, it is possible to continuously steer and guide the unmanned vehicle with a simple structure, and also to smoothly operate the unmanned vehicle. This has the excellent effect of making it possible to steer the car.

[Problem that the invention seeks to solve]

As mentioned above, the optical guidance system for unmanned vehicles that the applicant previously applied for has excellent effects, but as shown in FIG. We have developed a technology that takes advantage of the characteristics of the optical guidance method described above to guide an unmanned vehicle along the guidance zone 31 at a junction where the vehicle turns left, and also allows the unmanned vehicle to smoothly go straight and turn left and right. It wasn't.

The present invention has been made in view of the above-mentioned points, and at the branch point of the guide zone of the optical guidance system for unmanned vehicles having the above-mentioned configuration, the unmanned vehicle can smoothly move straight along the guide zone and to the left in response to a branching command. Another object of the present invention is to provide a photoelectric guidance system for an unmanned vehicle that can turn right.

[Means for solving problems]

In order to solve the above-mentioned problems, the present invention has been developed to provide an induction band extending from the floor surface using a pair of left and right photoelectric conversion elements attached to a vehicle body equipped with a steering motor and a motor drive device for driving the steering motor. The reflected light of is received by the photoelectric conversion element,
In the photoelectric guidance device for an unmanned vehicle that drives the steering motor via the motor drive device based on the output difference between the photoelectric conversion elements and guides the unmanned vehicle along the guidance zone, each of the pair of left and right photoelectric conversion A hold circuit is provided to fix the output of the element, and a maximum output detection circuit is provided to detect the maximum output of each photoelectric conversion element. Both outputs of the photoelectric conversion elements are fixed, and when the maximum output detection circuit detects the maximum output, the fixation is released at the falling edge of the output, and the unmanned vehicle is driven straight along the guide zone, and turns right at the branch point of the guide zone. Or, if there is an instruction to turn left, the hold circuit fixes the output of the left or right photoelectric conversion element, and when the maximum output detection circuit detects the maximum output of the fixed photoelectric conversion element, it detects the output at the falling edge. By releasing the fixation, the unmanned vehicle is configured to turn to the right or left along the guide zone.

[Effect]

With the above configuration, when the unmanned vehicle reaches the branch point of the guidance zone, depending on whether the instruction is to go straight, turn right, or turn left, if the unmanned vehicle is going straight, both outputs of the left and right photoelectric conversion elements are output. fixed, and guide the vehicle body with the fixed output,
At the point beyond the junction, the unmanned vehicle is guided again by the detection outputs of both photoelectric conversion elements, and in the case of a right turn instruction, the output of the left light 1 conversion element is fixed, and the output of the right light weight conversion element is used to guide the unmanned vehicle. After passing the junction, the unmanned vehicle is guided again using the detection outputs of both photoelectric conversion elements, and if a left turn is instructed, the output of the right photoelectric conversion element is fixed, and the output of the left photoelectric conversion element is used to guide the unmanned vehicle. The system guides the unmanned vehicle along the guidance zone by taking advantage of the characteristics of the photoelectric guidance method and smoothly branching and guiding the unmanned vehicle along the guidance zone in response to the branching command. .

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings.

First, the principle of the photoelectric guidance method for an unmanned vehicle according to the present invention will be explained using FIG. An unmanned vehicle equipped with a pair of left and right photoelectric conversion elements R and L is guided along the guide zone 31 and
When the vehicle reaches a branch point where the vehicle goes straight and branches left and right, it goes straight and turns along the guide band 31 to the left or right in accordance with the branch instruction from the branch instruction section 43. ``If there is a branch instruction to go straight ahead, the outputs of the left and right pair of photoelectric conversion elements R and L are fixed to prevent the driver from traveling, and at the point beyond the branch zone X, the photoelectric conversion elements R,
Unfix L and let it run using the normal guidance method. If the branch instruction is 'turn left', fix the output of the right light-grain conversion element R, turn left along the guidance zone 31 using only the left photoelectric conversion element, and at the point where it crosses the branch zone X. Release the fixation of the right photoelectric conversion element R and run using the normal guidance method. In addition, if the branch instruction is "1 right turn", the output of the left photoelectric conversion element R is fixed, and only the right photoelectric conversion element R is used to control the induction band 3.
1, at the point where the vehicle crosses the left turning branch zone X, the fixation of the left photoelectric conversion element is released and the vehicle is allowed to travel in the normal guidance method.

FIG. 1 is a block circuit diagram showing the system configuration of a branch guidance section to which the photoelectric guidance method of an unmanned vehicle according to the present invention is applied. In the figure, 1 is an oscillation circuit that generates clock pulses, 2 is a flip-flop circuit, 3 is a gate, 4 and 5 are drive circuits, 6 and 7 are light emitting diodes, 8 is a light emission control circuit,
9 is an adjustment resistor, 10.11 is an amplifier, 12.13 is a maximum output detection circuit, 14.15 is a sample and hold circuit,
16.17 is the amplifier, 18.19 is the gate, 20.21
is a flip-flop circuit.

In the branch guide section having the above configuration, the terminals T+ and T2 are connected to the output terminals of the photoelectric conversion elements 33 and 34 shown in FIG. 2, respectively, and the outputs of the terminals T and T are respectively connected to the second output terminal.
The outputs of the optical T-conversion elements 33 and 34 shown in the figure are connected to input terminals a and b of a differential amplifier 35 that can be inputted. Further, terminals T and T5 are connected to instruction signals A and B from a branch instruction section 43 provided at a branch point of the induction band 31 as shown in FIG.
A sensor (not shown) that reads the data can be connected.

The oscillation circuit 1 outputs a clock pulse P having the waveform shown in A in FIG. 6, and the gate 3 outputs a pulse P in the waveform shown in B in the same figure to the drive circuits 4 and 5. Drive circuit 4
, 5 activates the light emitting diode 6.7 with the pulse P, and the light corresponding to the pulse P, from the light emitting diode 6.7! ,
2 can be fired onto the guide belt 31 (see FIG. 2) stretched over the floor 32. The light reflected by the induction band 31 is detected by the left and right photoelectric conversion elements 33 and 34, and the output thereof is inputted to the amplifier 10 and 1 from the terminals T and T.

Assume now that the branch instruction signals A and B of the branch instruction section 43 are as shown in FIG. That is, the unmanned vehicle is in the guidance zone 31.
When driving normally along the branch direction signal A,
B is '0,0. ,'Go straight.

The branch instruction signals A and B at the time are '1, 1. , the branch instruction signals A and B at the time of "right turn" are '0, 1 . , ``When making a left turn, the branching instruction signals A and B are set to ``1°0''.

In normal running, the branch instruction signals A and B are "O20", so the flip-flop circuits 20 and 21 are not set, the sample and hold circuits 14 and 15 are not operating, and the amplifiers 10 and 11 are not set. The outputs of are amplified by amplifiers 16 and 17, respectively, and input to a differential amplifier 35 through terminals T and T. Based on the output signal from the differential amplifier 35, the steering angle signal generation circuit 36 generates a steering angle signal, and the steering angle signal causes the wheels 40 to turn to the right or left via the steering motor drive device 37 and the steering motor 38. However, the guide along the guide band 31 is similar to the above.

FIGS. 5(a), (b), and (C) are diagrams for explaining the operation of the unmanned vehicle when the branching instruction signal of the branching instruction unit 43 is "go straight ahead", "turn right", and "turn left", respectively. It is.

Each operation will be explained below.

In the case of "go straight", that is, the branch instruction section 9 of the branch instruction section 43
A and B are '1. In the case of IJ, flip-flop circuit 20
and 21 are set by the ``rl'' signal at terminals T3 and T, and the sample and hold circuits 14 and 15 are activated. As a result, the output values of the amplifiers 10 and 11 at that time are fixed and outputted from the sample and hold circuits 14 and 15. The outputs of the sample and hold circuits 14 and 15 are amplified by amplifiers 16 and 17, respectively, and input to a differential amplifier 35 through terminals T and T. As a result, the unmanned vehicle travels straight regardless of the actual outputs of the amplifiers 10 and 11. Photoelectric conversion element 33
and 34 cross the guiding bands 31a and 31c which bend left and right, and when the output reaches the maximum, the maximum output detection circuit 1
2 and 13 detect the maximum detection signals LMAX and RMAX, and at the falling edge, the sample and hold circuits 14
and sample hold circuit return signal L that returns 15.
S/H and R3/H are output, and flip-flop circuits 20 and 21 are reset.

This causes the vehicle to return to the normal guided travel.

In the case of "turn right," that is, when the branch instruction signals A and B of the branch instruction section 43 are '0, 1.', the flip-flop circuit 20
is set by the 11'' signal at the terminal T, but since the blip-prop circuit 21 cannot be fully set, the sample-and-hold circuit 14 operates, but the sample-and-hold circuit 15 does not operate. As a result, sample hold circuit 1
4, the output value of the amplifier 10 at that time is fixed and outputted, and the output of the amplifier 11 passes through a sample and hold circuit 15 and is inputted to the amplifier 17.

As a result, the unmanned vehicle is steered by the output from the sample and hold circuit 14 and the output from the amplifier 11.

That is, the right photoelectric conversion element 34 can guide the light along the guiding band 31c that bends to the right. The maximum output detection circuit 12 detects the output of the amplifier 10, that is, the output of the photoelectric conversion element 33, and detects when the photoelectric conversion element 33 crosses the guiding band 31a that bends to the left and the guiding band 31b that goes straight, and the output reaches the maximum. A sample-and-hold circuit return signal LS/H is output that returns the sample-and-hold circuit 14 at the falling edge of the maximum detection signal LMAX. As a result, the flip-flop circuit 20 is reset and the normal guided running is resumed.

In addition, in the case of 'left turn', that is, the branch instruction signals A and B of the branch instruction section 43 are '1, 0. In this case, the flip-flop circuit 21 is set by the rl signal at the terminal T4, but the flip-flop circuit 20 is not set, so the sample-and-hold circuit 15 operates, but the sample-and-hold circuit 14 does not operate. As a result, the unmanned vehicle is steered by the output from the amplifier 10 and the output from the sample and hold circuit 15. That is, the left photoelectric conversion element 33
As a result, the vehicle is guided along the guide band 31a that bends to the left. Further, the maximum output detection circuit 13
1 output, that is, the output of the photoelectric conversion element 34, the photoelectric conversion element 34 crosses the rightward bending guide band 31c and the straight-going guide band 31b, and the maximum detection signal LMAX is obtained when the output becomes maximum. is detected, and the maximum detection signal LMAX
At the falling edge of , a sample-and-hold circuit return signal R3/H is outputted to return the sample-and-hold circuit 15, and the flip-flop circuit 21 is reset, thereby returning to the above-mentioned normal guided running.

As described above, according to the photoelectric guidance device for an unmanned vehicle, when the unmanned vehicle reaches a branch point in the guide zone 31, depending on whether the branch instruction from the branch instruction section 43 is an instruction to go straight, turn left, or turn right, in the case of going straight, it turns left or right. The outputs of the pair of photoelectric conversion elements 33 and 34 are fixed by sample and hold circuits 14 and 15, the unmanned vehicle is guided by the fixed outputs, the fixation is released at the point beyond the branch point, and both photoelectric conversion elements are connected again. 33. The unmanned vehicle is guided by the detection output of 34, and in the case of a right turn instruction, the output of the left photoelectric conversion element 33 is fixed by the sample hold circuit 14, and the unmanned vehicle is guided by the output of the right photoelectric conversion element 34. Then, at the point beyond the branch point, the fixation is released and guidance is again provided by the detection outputs of both photoelectric conversion elements 33 and 34. Furthermore, in the case of a left turn instruction, the output of the right photoelectric conversion element 34 is sent to the sample and hold circuit 15. The unmanned vehicle is guided by the output of the left photoelectric conversion element 33, and when it crosses the junction, the fixation is released and both photoelectric conversion elements 33 and 34 are fixed again.
Since the system uses the detection output of the sensor to guide the unmanned vehicle, it is possible to take advantage of the features of the photoelectric guidance system and smoothly branch and guide the unmanned vehicle along the guidance zone in response to a branch command at a branch point. Please note that unmanned vehicles are placed in guidance zone 3.
The guidance device that allows guidance according to 1.
5), so the details will be omitted. [Effects of the Invention] As explained above, according to the present invention, when an unmanned vehicle reaches a branching point of a guide zone, if the branching instruction is to go straight, Both outputs of the pair of left and right photoelectric conversion elements are fixed with a hold circuit, and the unmanned vehicle is guided by the fixed output, and when it crosses the junction, it is guided again by the detection outputs of both photoelectric conversion elements, and a right turn is instructed. Alternatively, in the case of a left turn instruction, the output of the left photoelectric conversion element or the output of the right photoelectric conversion element is fixed with a hold circuit, and the unmanned vehicle is guided by the output of the right photoelectric conversion element or the left photoelectric conversion element, Since the detection outputs of both photoelectric conversion elements are used to guide the vehicle once it crosses the branch point, it has the excellent effect of making use of the features of the photoelectric guidance method and smoothly branching and guiding the unmanned vehicle along the guidance zone in response to the branch command. is obtained.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing the system configuration of a branch guidance section to which the photoelectric guidance method of an unmanned vehicle according to the present invention is applied;
The figure shows an overview of the system configuration of the optical guidance device for unmanned vehicles that the present applicant previously applied for, Figure 3 shows the branching point of the guidance zone, and Figure 4 shows the branching instructions of the branching indicating section. Figure 5 showing signals and operating states of left and right (R, L) photoelectric conversion elements
Figures (a), (b), and (c) are diagrams for explaining the operation of an unmanned vehicle at a branch point, respectively, and Figure 6 is a diagram showing the waveforms of the clock pulse of the oscillation circuit and the activation pulse of the light emitting diode. be. In the figure, 1: oscillation circuit, 2: flip-flop circuit, 3: gate, 4, 5: drive circuit,
6.7...Light emitting diode, 8...Light emission control circuit, 9...Adjusting resistor, 10.11...Amplifier, 12.13...Maximum output detection circuit, 14 .15・
...Sample and hold circuit, 16.17...Amplifier, 18.19...Gate, 20.21...Flip-flop circuit, 31...Induction band, 32...
・Floor surface, 33.34...Photoelectric conversion element, 35...
・Differential amplifier, 36...Steering angle signal generation circuit, 37
... Steering motor drive device, 38 ... Steering motor, 39 ... Potentimeter, 40 ... Wheels,
41... Travel motor, 42... Travel motor drive device.

Claims (1)

[Claims] A pair of left and right photoelectric conversion elements attached to a vehicle body equipped with a steering motor and a motor drive device for driving the steering motor receive reflected light from an induction band stretched on the floor surface with the photoelectric conversion elements. , in the photoelectric guidance device for an unmanned vehicle that drives the steering motor via the motor drive device based on the output difference of the photoelectric conversion element to guide the unmanned vehicle along the guide band, each of the pair of left and right photoelectric converters A hold circuit is provided to fix the output of the conversion element, and a maximum output detection circuit is provided to detect the maximum output of each photoelectric conversion element. Both outputs of a pair of photoelectric conversion elements are fixed, and when the maximum output detection circuit detects the maximum output, the fixation is released and the vehicle proceeds straight along the guidance zone, and at the fork, there is an instruction to turn right or left. In this case, the hold circuit fixes the output of the left or right photoelectric conversion element, and when the maximum output detection circuit detects the maximum output of the fixed photoelectric conversion element, the fixation is released, thereby guiding the vehicle body. A photoelectric guidance system for unmanned vehicles that allows them to turn to the right or left along a band.