JPS60160413A - Guiding device of mobile body - Google Patents

Abstract

PURPOSE:To obtain steering and stable driving with high accuracy by picking up the image of a road mark at the driving path region by means of an image pickup device before and after the mark and obtaining the forecast drive state amount in front and the history drive state amount at the back to apply steering control. CONSTITUTION:An unattended truck 1 is driven by detecting a road mark 4 adhered onto a line 3 of a drive path 2. The image pickup device 6 is fitted before and after the unattended truck 1, detects the said mark 4 and a driver 8 controls a steering mechanism 7 fitted to a drive wheel 9 and drive wheels 9, 10. Moreover, a steering signal and a drive signal are inputted to a control section of a control panel 11 to control the steering mechanism 7 and the driver 8 and a processing section 12 processes data. In this case, the image pickup device 6a detects the mark 4a in front of the truck 1 to operate the forecast drive state amount and the image pickup device 6b detects the mark 4b at the back to operate the history drive state amount respectively and the forward/reverse steering signal is operated from both the state amounts.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention captures an image using a mark-like imaging device affixed on a running road surface, processes the image to determine the amount of deviation from the planned running road, and calculates the amount of deviation from the planned running road. The present invention relates to a guiding device for a moving body that guides the moving body so as to eliminate the problem.

[Background of the invention]

One of the typical moving objects is an automatic guided vehicle, and in order to move this automatic guided vehicle along a designated travel route, a traveling detection device is required to detect the traveling situation.

Conventionally, this running detection device was of the electromagnetic induction type.

Tape optical type, capacitive type, ultrasonic type, visual guidance type, etc. are known. Among these, the visual guidance type attaches marks at equal intervals in the center of the travel route, and an imaging device attached to the moving object captures images of the marks, which are then image-processed to determine the route from the planned route. This detects the amount of deviation.

Therefore, a guidance device using a visual guidance system guides a mobile object onto a planned travel route by utilizing the state quantity detected in this manner.

However, conventionally known guidance devices of this type detect the running situation in front of the moving object, that is, the trajectory deviation, inclination, and amount of movement of the moving object in front of the moving object, and use this as predictive information to drive the running wheels on both the left and right sides. Steering is performed by controlling the speed difference between the two motors. Alternatively, a steering mechanism is attached to the wheels, and the aforementioned predictive information is used to control the steering.

Therefore, if only such control is used, the moving object will meander significantly from side to side on the traveling road, making it difficult to run stably.

On the other hand, in conventional guidance devices of this type, the mark is provided in the center of the travel path of the moving object, and as the wheels of the moving object move over the mark, the mark may become dirty or scratched. The reliability of the mark is a problem because the marks may be damaged or missing parts may occur.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a steering device for a moving body that can perform crystal-accurate steering.

[Summary of the Invention] The present invention provides a method for marking marks forming a travel path for a moving body.
1, an imaging device is provided to take an image of the mark at the front and rear of the moving body, and a steering mechanism is provided on each of the front running wheels of the moving body, and the image taken by the imager I device of each ITI is provided. an image processing unit that detects a forward predicted running state quantity and a backward historical running state quantity by image processing, respectively; and a steering signal for each of the steering mechanisms using the predicted running state quantity and the historical running state quantity. The present invention is characterized in that it includes a control amount calculation section that determines the amount of control, and a control section that controls the steering mechanism using the steering signal.

[Embodiments of the invention]

Hereinafter, the present invention will be explained in detail based on specific examples.

First, the overall configuration of an automatic guided vehicle, which is a type of moving object, will be explained with reference to FIGS. 1 to 3. FIG. 1 is an overall perspective view of the automatic guided vehicle, FIG. 2 is a side view thereof, and FIG. 3 is a diagram showing a traveling device portion including a steering mechanism. In FIGS. 1 and 2, reference numeral 1 denotes an automatic guided vehicle that travels on a travel path 2. 3 is a line for forming a running route. In other words, the inside of Gen 3 is the travel path of the automatic guided vehicle. 4a, 4b
is a road mark pasted on line 3, and unmanned transportation It
fl uses this mark to drive. 6a.

6b is an imaging device attached to the front and rear of the automatic guided vehicle 1, which images the marks 4a and 4b, respectively. 5a
and 5b indicate the imaging area (field of view) of each imaging device. 7a and 7b are steering mechanisms attached to the front and rear running wheels. 8 is a running device for running the carrier. 9'a and 9b are running wheels provided at the front and rear;
0a and 10b are running wheels provided on the left and right sides. In addition,
9a and 9b are driving wheels, and 10a and 10b are subordinate wheels. Reference numeral 11 denotes a control panel, into which steering signals and running signals are input, and the steering mechanism and running! It includes a control section that controls the J position. 2 is a processing unit that processes data, including an image processing unit that calculates running state quantities from imaged information, and a control 'I# calculation unit that calculates control signals (steering signals and running signals) from the running state quantities. including. 13 is a battery device that supplies power to each device; 14 is a loading platform; and 15 is a wireless device for receiving travel command signals from a ground communication station. The steering mechanism 7a and the traveling device 8 in FIGS. 1 and 2. FIG. 3 shows the running wheel 9a in detail. In FIG. 3, the traveling device 8 has a traveling motor 16, a shaft 17b coupled to a motor shaft 17a, a spur gear I8.19, and the rotational direction of power transmission between the spur gears 18 and 19 at right angles. Bevel gears, 20a, 20b to be converted into
, the main shaft 21a of the bevel gear, and both end bearings 22a, 22
b, and a member 21 that connects the running wheel 9a and the main shaft 21 with a boss.
It is composed of b. The casing n includes a spur gear train 18°19, an east row of bevel teeth 20a, 20b, and a main shaft 21a.
1. Both end bearings na122b etc. are integrated. The steering mechanism 7a is fixed to the vehicle body side and includes a steering motor 5 and a spur gear 24a that decelerates the rotational movement of this motor via a shaft.
and a member I that fixes the main shaft 24b to the casing 23. Steering is performed by rotating the steering motor 25 and swinging the casing. Although not shown, the steering wheel a#7b has a similar configuration and is configured to swing the running wheels 9b.

Next, a configuration for controlling the automatic guided vehicle shown in FIGS. 1 to 3 will be explained using FIG. 4. In FIG. 4, 6a, 6b1. is an imaging device, and only 6a is disclosed in detail. Reference numeral 12 denotes a processing unit, which is composed of an image processing unit and a control amount calculation unit 35. The control unit 11 is
It receives the control signal that is the output of the control amount calculation section 35, and controls each of the steering mechanisms 7a, 7b and the traveling device 8 in accordance with the control signal. Now, the imaging device 6a (same as 6b) inputs an image of the line 3 and the road mark 4a attached thereon through a camera 29a configured with a filter T and no lens. That is, the optical image input through the camera is projected onto the solid-state image element Tagami, and excites the photodiodes 31 arranged in a matrix to generate lightning current in the circuit, which is transmitted through the load resistor 32. After converting the signal into a voltage, the preamplifier 33 amplifies the signal and inputs the image as an electrical image signal.

This input image signal is supplied to the analog/digital converter 37 in the image processing section 34 via Kirisugi Kita, and is converted into a digital signal. The image signal converted into a digital signal is stored in the image memory 38.

Imaging device! ! The image signal inputted by 6b is also analog/digital converted 91! via the switch 36.
37 and stored in a converter image memory 38 as a digital signal. Since the switching of the switching device I is performed at high speed, the image memory 3B stores the latest image signals input by the respective imaging devices 6a and 6b. Since the imaging devices 6a and 6b are provided at the front and rear of the transport vehicle, the image memo 1J3B stores an image signal from the front in the traveling direction of the transport vehicle and an image signal from the rear. The image processor 40 calculates the running state amount using the image signals stored in the image memory 38 according to an image processing algorithm stored in the program memory 39.

Note that the load resistor 32 is adjusted when there is a change in illuminance in the viewing area due to disturbance light or a change in contrast due to dirt on the line 3° road surface mark. The control amount calculation section 35 stores the running state amount calculated by the image processing section 34 in the data memory 42.
and the steering/control data stored in program memory a.
Control signals (steering signals and running signals) are calculated by the control processor 41 according to the running control algorithm.

These control signals are supplied to the control section 11, and the control section 11 controls the steering mechanisms 7a, 7b and the traveling device 8 using these as command signals. 44a and 44b are control amplifiers.

Next, a method of calculating the steering signal will be explained with reference to FIG. Assuming that the images input by the imaging devices fia and 6b are 45 and 46 in FIG. 5, the data on the three fixed lines are al, a2, . bllb2゜CI +
C2 and aH,a;, b;, bH,c;, c;
The position coordinates of Using these, the calculation unit 47 calculates each running state m. The predicted running state quantity, that is, the running state quantity obtained from the front imaging device (y1+91°x
l) can be calculated as follows.

The trajectory deviation y1 is as follows: y1=] (b1+b2) 1' (a1+ a2+cl+ c2) ・---・=
(The 11th place W Xl is obtained from the mark count value. Also, the historical running state quantity, that is, the running state B it (y2 + 92 + X2) obtained from the rear imaging device is determined as follows.

Orbit deviation view y2 is 1/7 y2= -T-(J+ b2) 1/I-17 -T(81+a2+ cI+c2) ------(3)
The position x2 is obtained from the mark count value.

In addition, the predicted running state quantity and historical running state 1! ! Using the quantity, the running state quantity at the center position of the transport vehicle, that is, the current running state quantity (ys + color, x3) can be determined as follows.

Orbit deviation Q ys is -" - ys-2 (Y1+ y2) ・Curve... Concave bend (5) Attitude angle ψ is ψ3=-T-(ψ1+92) ......Song (6)
) Traveling position rI1. x3 is x3 = 1 (x1 + x2) +++++++++++ (7) Using each of these driving state quantities, each front side and rear side steering 8
! The amount of steering applied to the structure δ1. a2 is determined as follows.

a) δ1 = 01 in high-speed straight sections and accelerated turning sections
()'1+(1+d) ψ1)・・・・・・・・・・・・
...(8) δz--02()'2+ (1+ a
)ψ2)・・・・・・・・・・・・・・・(9) However, δ1', steering amount δ2 of W wheel (running wheel 9a): rear wheel (
Steering amount Gl, G2 of running wheel 9b): operation gain constant l! : Length d of the automatic guided vehicle 1 : Distance from the imaging device Mj6a to the front subject b) In the low-speed straight section and deceleration turning section, δ=-01(y1+(
l! +d)ψ1)...Concave curve (1°δ= 02(3'
z+(/+d)ψ2) ・・・・・・・・・・・・・・・
-Qj However, G3: Operation gain constant As described above, the steering amount differs depending on the driving mode of the automatic guided vehicle.

Next, the flow of each processing operation of the image processing section 34 and the control amount calculation section in FIG. 4 will be explained using FIG. 6 (al) and FIG. 6 (bl).

First, the processing operation flow of the image processing unit M will be explained using FIG.
p) is executed as follows.

Step (bl: Adjust the gains of the imaging devices 6a and 6b regarding the 2# threshold level, which will be described later, so as to reliably recognize images of white lines or road markings.

Steps (cl, (cl', (dl: m) After confirming that the imaging devices 156a and 6b operate normally, the image capturing devices 6a and 6b image the scene on the two surfaces of the running path, and The presence or absence of obstacles in front of the driving path is confirmed, and the image of the white line 3 or each mark 4a*4b is input.

Step (e): The analog voltage amplified by the preamplifier is sequentially input to the A/D converter 37 to convert the image signal into a digital signal.

Step (f): Transfer the digital signal to an image memory blade connected to the image processor and store it sequentially.

Steps (gl~(j): Binarization processing of the digital signal stored in the image memory 38, that is, by setting a digital threshold level, signals above that level value are set to "1", and signals below that level are set to "1". After converting the signal to 0° and specifying a storage address, it is stored again in the image memory 38.

At that time, the total area showing the "1" signal is output to determine whether a white line or road mark is detected, and if it is not normal, the threshold value is lowered step by step.
゜Step 0): Binarized white line 3 or road mark 4
Extract the features of the edge signals in ``11'' and ``10'' of a and 4b, and extract the features of the edge signals in ``11 and 10'' of a and 4b, and calculate
+ G2) (CIl 02) and (81,;l2)
(e'1+c2) is calculated.

Step (kl, (/'l: (From the address calculated in jl, center address (+(a1+82) +
z (c1+G2) ) T(T(a1+G2)
, 2 (cl+G2)).

Step 2: The captured image of the white line 3 and the image of the mark 4a are identified. Note that the determination of whether the course is a straight course or a turning course is made by identifying the shape of the mark, and the movement position and movement course of the automatic guided vehicle 1 are ascertained.

Step -, (nl nistep (among the center address values determined by kl, as shown in FIG. 5, the forward state quantity, that is)'++9'i and the rear attack Ry2 +92 are calculated.

Step (ol, (p) Nistep f) ~ (to)
The count number r of mark images calculated by, the orbit deviation amount Y1
+3'2+attitude angle ψ1. The running state quantities such as ψ2 and mark shape identification are sequentially transferred to the control amount calculation unit. Then, jump to step fe) again and step (el~(p
Repeat l.

Next, the processing operation flow of the control amount calculation section is shown in FIG.
Explain using.

Step (5) Initial settings are performed by turning on the power.

Step (E): Set the moving address = J of the position to be moved, and drive the steering mechanism and traveling device.

Step (O: Check the presence or absence of the driving state quantity signal transferred from the image processing unit A.

Step (g): Based on the transferred running state quantity,
It determines whether it is going straight or turning, and if it is turning, it jumps to step (G).

Jump to step (D: Compare the moving address J and the count number r, and if J≦r+1, go to step 0).

Step (Fl, TG: The operation of this step is performed when steady straight-ahead driving is performed. In other words, using the predicted driving state Ji yl +91, the above-mentioned (
8).

(9) is calculated, and each steering amount δ1. δ2 is observed. These δl and δ2 are output to the control unit 11, and the husband's steering mechanism is controlled.

Steps 0 to (6): A deceleration command (a type of traveling signal) is output to the control unit 11 in order to decelerate the traveling device 8. Then, among the predicted driving state quantity and the historical driving state quantity, )'1
+3'2 Using +ψl and ψ2, each steering amount δ1
Calculate °δ2. The calculation formula is the above-mentioned QO (111 formula).

This δ1. δ2 is output to the control unit 11, and each steering mechanism is controlled. Then, the automatic guided vehicle 1 is driven at a slow speed by a timer operation, and then stops at the target position.

Steps (Ll~(N: In the case of a deceleration region where the front imaging device 6a detects a turning mark image on the running road and the rear imaging device t6b detects a mark image on a straight running road,
δ and δ are calculated according to the acl.01 formula. Also, the imaging device g? , 6 a , and 5 b are steady turning sections in which turning mark images on the road were detected, respectively.
δ1. δ2 is calculated according to equation (12).Furthermore, the front imaging device 6a detects a mark image on the straight traveling road,
In the case of an acceleration section where the rear imaging device [6b is still detecting marks on the turning road, the above-mentioned (7) (81, (9
According to Equation 1, h and h are calculated. The steering amount calculated in this way is supplied to the control unit 11 as a steering signal, and each steering @97a, 7b is controlled.

As described above, according to this embodiment, a road surface mark is provided on a line indicating a driving road area, and the front and rear imaging devices take images of the road mark, thereby making it possible to estimate the forward predicted driving state quantity and the backward historical driving state quantity. , fine-grained steering control is performed based on these driving state quantities. Therefore, the automatic guided vehicle can travel on the road with high precision. Of course, the road mark is provided on a line with both elevations of 1μ that will not be broken by the running wheels of the transport vehicle, and the reliability of the mark is high.

〔Effect of the invention〕

As described above, according to the present invention, highly accurate steering can be performed and stable running of the moving body can be realized.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view of the automated guided vehicle, Fig. 2 is a side view of the automated guided vehicle, Fig. 3 is a diagram showing a traveling device including a steering mechanism, and Fig. 4 shows an embodiment of the present invention. Figure 5 is a diagram for explaining the calculation method of the steering signal, Figure 6 (a), Figure 6 (bl is a diagram showing the operation of the embodiment shown in Figure 4.1... ...Automated guided vehicle, 2...Travel path, 3
... Line, 4a, 4b ... Road mark,
6a, 6b...imaging device, 7a, 7b...
... Steering mechanism, 8... Traveling device, 9a, 9b.
...Running wheel,]1...Control unit, 12...
...Processing section, 34... Image processing section, 35.
...Controlled amount calculation section. Figure 5, Figure 6 (α)) Figure 6 (b)

Claims (1)

[Claims] 1. In a guidance device for a moving object that includes an imaging device in a moving object, processes the image signal captured by the imaging device, and guides the moving object using the output of a processing unit that calculates a control amount, the device moves in front of and behind the moving object. An imaging device installed to be able to take images of marks on the line forming the road, a steering mechanism installed on the front and rear running wheels of the moving object, and a prediction system that processes the image signals of the front and rear imaging devices, respectively. an image processing unit that calculates a running state quantity and a historical running state quantity; a control amount calculation unit that inputs the calculation results of the image processing unit and calculates front and rear steering signals for controlling the steering mechanism; A guiding device for a moving body, comprising: a control section that controls the steering mechanism using a signal.