JPH01163609A - Position detecting device for unmanned vehicle - Google Patents

Abstract

PURPOSE:To measure the position and speed of a vehicle body with high accuracy by providing an optical system sensor to the vehicle body and processing its detection signal through a linear sensor. CONSTITUTION:A lens system is so constituted that optical systems 20A and 20B form an image on a line sensor through a cylinder lens in a direction parallel to the line sensor and the line sensor is at the focus in a vertical direction. Video signals of the optical systems 20A and 20B are detected by video detection parts 30A and 30B and inputted to spatial films 40A and 40B. The filters 40A and 40B detect specific spatial frequency components from the optically random pattern of a road surface, their outputs are processed by arithmetic processing parts 50A and 50B to find the movement distance, and the ratio is differentiated by time to find the speed. When the detection is performed at a period much smaller than the motion of the vehicle, a change in the direction of the vehicle is found from the difference in movement distance measured value in one period between the processing parts 50A and 50B and it is considered that the vehicle travels with the mean value in the period. Consequently, the position and speed are measured with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a position detection device for an unmanned vehicle, and more particularly to a position detection device for an unmanned vehicle that detects the running position, running speed, and travel distance of the unmanned vehicle.

I3 Summary of the Invention The present invention provides a position detection device for an unmanned vehicle that detects various running states by installing a detector for detecting running states on the body of the unmanned vehicle, which comprises: installing an optical sensor on the vehicle body; By processing the detection signal of the optical sensor with a one-dimensional spatial filter and detecting the two-dimensional position, velocity, and direction of movement of the vehicle body from the output, =3- an unmanned vehicle with excellent detection accuracy can be realized. A position detection device is obtained.

C. Conventional technology In the past, when automatically driving unmanned vehicles such as automatic guided vehicles, there were methods in which electromagnetic induction wires or optical reflective tape were laid on the road to form a travel guide, and encoders and tachos were installed on axles and measuring wheels. There is a method of attaching a generator and measuring the speed and travel distance of an unmanned vehicle from pulses or analog voltages corresponding to the rotation of the wheels.

D9 Problems to be Solved by the Invention In various conventional position detection devices, it is necessary to process the running path by laying guide wires, reflective tape, etc. on the road surface, which is troublesome and also causes problems due to unevenness of the road surface. , Accurate measurement was not possible due to wheel slippage and wheel wear caused by external forces.

E9 Means for Solving Problems The present invention has been made in view of two problems, and includes: an optical system disposed on the bottom of the vehicle body for photographing the pattern of the road surface; a video detection unit that obtains a video pattern signal by sampling a video pattern taken by the video detection unit at a predetermined period; and a video detection unit that multiplies the video pattern signal of the video detection unit by a preset trigonometric function setting signal, and integrates the multiplied signal. A filter means for calculating and obtaining a trigonometric function pattern signal, and an arithmetic processing section for calculating a moving distance signal of the vehicle body by performing multiplication and addition processing based on the trigonometric function pattern signal of the filter means.
to detect the position, speed, and direction of unmanned vehicles.

F. Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a position detection device for an unmanned vehicle according to an embodiment of the present invention, in which 10 is the vehicle body of the unmanned vehicle, 12 is the running wheel, and 2OA is the traveling axis of the unmanned vehicle at the bottom 11 of the vehicle body 10. A first optical system 20B is a first optical system 2OA disposed at one side end of the bottom part 11 with respect to the center (X axis).
The other side end (Y
This is a second optical system disposed on the axis "-). 30A is a first image detection section that inputs the image signal of the first optical system 2OA, 40A is a first spatial filter that uses the image detection signal of the first image detection section 30A as input, and 50Δ is the first The arithmetic processing unit performs arithmetic processing based on the filter output signal of the first spatial filter 4OA to calculate the moving distance, speed, and current position of the unmanned vehicle. These first optical system 20A, first image detection section 30A, first spatial filter 4. The OA and the first arithmetic processing section 50A constitute a first detection processing section 60A. Similarly, 20B is the second optical system,
3013 is a second video detection unit; 4. OB is a second spatial filter, 50B is a second arithmetic processing section, and these constitute a second detection processing section 60B.

The first detection processing section 60A and the second detection processing section 60B are composed of the same components as shown in FIG. Zunawaji, as shown in Figure 2, the first. The second video detection units 30A and 30B are line sensors 31. It is composed of a readout circuit 32 and an analog/tintal converter (A/D converter) 33. 1st. Second spatial filter 40A, 4. OB includes multiplication units 4i, a, 41b, pattern setting units 4.2a, 42b, and integral calculation units 43a, 43.
It is composed of b.

1st. The second calculation processing units 50A and 50B include low-pass filters 51a and 51b, a trigonometric function calculation unit 52, a phase calculation unit 53. Wasa calculation section 54. It is composed of a multiplication section 55, a differential calculation section 56, and a rotation trajectory calculation section (m calculation section) 70. As shown in FIG. 3, the m calculation section 70 is a sine wave signal calculation section 71a.

71b, multiplication units 72a and 72b, data holding units 73a to 73c which are previous value holding units, and summation unit 74a.

74b.

Figure 5 is 1. This shows a specific example of the configuration of the second optical systems 20A and 20B, and in FIG.
22 is a collimator lens that receives reflected light from the cylindrical lens. In addition, FIG. 6 shows another example of the optical system, in which the reflected light from the road surface at 8° is reflected by the collimating lens 22.
The light is focused on the cylindrical lens 23.

Next, the operation of the position detection device having the above configuration will be explained.

The optical systems 2OA and 20B are as shown in FIGS. 5 and 6,
Line sensor 31 by cylinder lenses 21, 24
The lens system is configured so that an image is formed on the line sensor 31 in a direction parallel to the line sensor 31, and the line sensor 31 is the focal point in a direction perpendicular to the line sensor 31. Optical system 2OA, 2
The video signals of 0B are the 1st. Second video detection unit 30
A, detected at 30B, 1st. Second spatial filter 4o
Δ.

4. Input to OB. Spatial filter 40A, /IO
B detects a specific spatial frequency component from an optically random pattern on the road surface and examines its temporal behavior to determine the position of the vehicle body relative to the road surface and its speed.

Schematically, as shown in FIG.
(30B), and its output is manually input to the spatial filter 40A (40B).

In the spatial filter, a sum-of-products operation is performed using human input values and a pre-calculated and pre-set setting pattern. Here, a sine wave pattern is used. The setting pattern has data for a period determined by the number of elements and pitch of the line sensor 31 of the video detection section 30A (30B).

The output of the spatial filter is processed by the calculation processing unit 50A (50B) to calculate the moving distance of the weight, and this moving distance is differentiated with respect to time to find the speed. In addition, when detecting the position at a cycle that is sufficiently small compared to the movement of the car, the change in the direction of the car is calculated from the difference between the measured values of the moving distance in one cycle of the two detection processing units, and the average value of the change is calculated. Find the position of the vehicle assuming that it traveled during that period.

More specifically, as shown in FIG.
Manually input to 0A (30B). Video detection unit 30A (3
In 0B), the line sensor 31 detects the image, the image detection signal is read out by the readout circuit 32, and the image detection signal is A/D converted and sent to the spatial filter /10,14.
0B). In the spatial filter 71OA (40B), the summation unit 4 ], the video detection unit 30A (
30B) and the sine wave pattern setting signal of the pattern setting section 42a are multiplied together, and the multiplication section 41b multiplies the video detection signal and the cosine wave pattern setting signal of the pattern setting section 4.2b. Further, the multiplication signal of the first multiplication section 41a is integrated by the integral calculation section 43a and the integrated signal a is outputted, and the multiplication section 4. ], b is integrated by a second integral calculation unit 4.3b, and the integrated signal S is outputted.

In the arithmetic processing unit 50A (50B), the integral signal is passed through a low-pass filter 5]a to obtain a signal Sa, and the integral signal S2 is passed through a low-pass filter 51b to obtain a signal sb. The signals Sa and Sb are each manually input to a trigonometric function calculation unit 52 and a seven-rotation locus calculation unit (m calculation unit) 70.

The trigonometric function calculation unit 52 calculates based on the signals Sa and sb,
Calculate the output ρ−12° arctan (S b /S a). The phase calculation unit 53 calculates (ρ−φ)/2 based on the input ρ and the initial phase φ.
Calculate π.

In the m operation section 70, as shown in FIG.
] through the wasan section 74. b and data holding unit 731]. The multiplication unit 72b multiplies the previous sampling value from the data holding unit 73a by the current sampling value. The summation unit 74 stores the current sampling value and the data holding unit 7.
The previous sampling values of 3b are summed. Multiplication section 72b
multiplies the multiplication value of the multiplication unit 72a by the summation value of the summation unit 74b, and the summation unit 74. A adds the current multiplication value of the multiplication unit 72b and the previous value of the data holding unit 73c, and outputs m signals.

Furthermore, in the arithmetic processing section 50A (50B), as shown in FIG. The moving distance is calculated by multiplying the added value by the pitch (period) P of the spatial filter, and this moving distance signal is input to the differential calculation unit 56 to calculate the speed.

As shown in FIG. 1, when the center point of the bottom surface 11 of the vehicle body 10 is defined as A (x, y), and the vehicle is traveling in the direction of the arrow, the vehicle is θ relative to the X axis on the XY plane. Suppose it is moving at an angle of. Here, the first . The outputs of the second detection processing units 60A and 60B, △r, ΔQ (position)
Assuming that the change in the traveling direction of the vehicle body 10 is short, Δθ-(f2-r)/I) (1), and the current angle θr1 of the vehicle body 10 is 0n. -On-1180...(2). Here, θn-1 is assumed to have moved at the time of the previous sample (r) blowfish, as shown in the following equation (3),
From (4), (xn, y.) can be found at the position of point A.

Here, n is the current coordinate, and n-1 is the previous coordinate. Therefore,
Calculate equations (1) to (4) to determine the position of the car (x).

y) and the direction θ.

The two outputs of the spatial filter rotate on the phase plane according to the movement of the car, as shown in FIG. Therefore, the traveling distance is calculated by the following formula.

Xo=(2πm+ρ-P)/old(=mXP-t-(ρ-
φ) / 2 rr P = (5) However, m is the number of rotations of the trajectory around the origin (counterclockwise is positive), Xo
is the moving distance, ■) is the pitch (period) of the spatial filter, ρ
-arctan (S b/Sa), 0≦p<2yr+
P=ρt=O (initial value).

Figures 7 and 8 show the above-mentioned operation flow.
The figure shows the calculation flow of the spatial filter 40A (40B), No. 8
The figure shows the calculation flow of the calculation processing section 50A (50B).

As shown in FIG. 7, in step Sl, the line sensor (C
CD) is A/D converted and input to the spatial filter. In the spatial filter, as shown in step S2, a sine wave (sin) pattern is read as window function data 1, and a product-sum operation of this sine wave pattern and the CCD output is executed (step S3). Next, as shown in step S4, a cosine wave (cos) pattern is read as window function data 2, and a product-sum operation of this cosine wave pattern and the CCD output is performed (step S5). Then, as shown in step S6, the operations of steps 81 to S5 are repeated 1.8 times per the number of CCD elements, for example, 20.

As shown in FIG. 8, in the arithmetic processing section, the output signals a and b of the spatial filter are passed through a one-dimensional low-pass filter, respectively. S8), as shown in step S9, the number of times the trajectory on the phase plane changes between the first and fourth quadrants, with the direction of movement from the fourth quadrant to the first quadrant being positive;
Count and perform m operation. Then, as shown in step Sho, p = arctan (S b / S a
) in the range O≦ρ<2π and perform phase calculation,
As shown in step S11, m-P+(ρ-P)/2
In addition to calculating π·P and executing a distance calculation, as shown in step S12, the distance is differentiated and a speed calculation is executed.

FIG. 9 shows another embodiment of the present invention, in which a microcomputer 90 is used as the arithmetic processing section. The microcomputer 90 includes a central processing unit (CPU) 91. ,
It is composed of a random access memory 92 and a read only memory (ROM) 93. As mentioned above, the road surface pattern is detected by the CCD through the optical system, and its output is inputted to the microcomputer 90 through the A/D converter, and its value and pre-calculated values are stored in the ROM 93.
The arithmetic processing described above is executed based on the setting pattern stored in the .

G1 Effects of the invention As described below, the present invention provides an optical system sensor on the vehicle body,
The detection signal of the optical system sensor is processed by a one-dimensional filter means, and the two-dimensional position, speed, and traveling direction of the vehicle body are detected from the output. This eliminates the need for contactless measurement, and enables highly accurate position and speed measurements without being affected by road surface irregularities, slips caused by external forces, or wheel wear.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the position detection device according to the present invention, FIG. 2 is a block diagram showing details of the detection processing section according to the embodiment of the present invention, and FIG. 3 is a block diagram of the rotation trajectory calculation = 19- section. Figure 4 is a rotation trajectory diagram of the rotation trajectory calculation section, Figures 5 and 6 are configuration diagrams of the optical system, and Figure 7
8 is a calculation flow diagram of the spatial filter, FIG. 8 is a calculation flow diagram of the calculation processing section, and FIG. 9 is a block diagram showing another embodiment of the detection processing section. DESCRIPTION OF SYMBOLS 10...Vehicle body, 11...Bottom part of vehicle body, 2OA...1st optical system, 20B...2nd optical system, 30A...1st image detection unit, 30B...2nd image Detection part, 40A
...First spatial filter, 40B...Second spatial filter, 50A -First arithmetic processing section, 50B...Second arithmetic processing section, 60A...First detection processing section, 6013
...Second detection processing section. To −

Claims (2)

[Claims] (1) an optical system disposed on the bottom of the vehicle body that captures the pattern of the road surface; an image detection section that samples the image pattern captured by the optical system at a predetermined period to obtain an image pattern signal; filter means for multiplying the video pattern signal of the video detection section by a preset trigonometric function setting signal and performing an integral operation on the multiplied signal to obtain a trigonometric function pattern signal; and an arithmetic processing unit that calculates a moving distance signal of the vehicle body by performing multiplication and addition processing on the vehicle body. (2) A first optical system disposed on the bottom of the vehicle body that photographs the pattern of the road surface, and a video pattern signal taken by sampling the video pattern taken by the first optical system at a predetermined period. a first image detecting section to obtain a trigonometric function pattern signal; a filter means, and a first filter means for calculating a moving distance signal of the vehicle body by performing multiplication processing based on the trigonometric function pattern signal of the first filtering means, and calculating a speed signal by differentially calculating the moving distance signal. a first detection processing means consisting of an arithmetic processing unit; and a first detection processing means disposed on the bottom surface of the vehicle body at a predetermined distance from the first optical system with respect to the axis in the traveling direction of the vehicle body, and captures a pattern of the traveling road surface. a second image detection unit that samples the image pattern captured by the second optical system at a predetermined period to obtain an image pattern signal; a second filter means for multiplying the pattern signal by a preset trigonometric function setting signal and performing an integral operation on the multiplied signal to obtain a trigonometric function pattern signal; a second detection processing means comprising a second arithmetic processing section that calculates a moving distance signal of the vehicle body by multiplying the moving distance signal, and calculates a speed signal by differentially calculating the moving distance signal; a moving distance signal obtained by the detection processing unit 1;
It is characterized by comprising means for calculating the traveling direction angle of the vehicle body based on the moving distance signal obtained by the second detection processing section and the installation interval between the first optical system and the second optical system. A position detection device for unmanned vehicles.