JPS6195413A - Travel control system of moving car - Google Patents

Abstract

PURPOSE:To attain automatic travelling even in any traveling area by mounting a fault detector on a moving car to search an unknown obstacle, store the searched result in a memory and travel the moving car so as to keep the car away from the obstacle. CONSTITUTION:The unit moving distance of the moving car 1, the increment of a distance to be used for the retrieval of an obstacle and the increment of an angle are previously set by a travel control device 22 and stored in a memory 22b. The obstacle in the traveling area is seatched by an obstacle searching device 18 mounted on the moving car 1 and the position of the obstacle is sequentially stored in the memory 22b. To search a route, the obstacle is searched by adding or subtracting the distance and angle increments to/from a straight line connecting between the current point of the moving car 1 and an objective moving point in a circle defined by the unit moving distance around the current point as its radius on the basis of information stored in the memory 22b, the succeeding moving point to which the moving car 1 may be moved without being interrupted by the obstacle and its advancing direction are determined and then a steering angle and a car speed are also found out. These results are sent to a traveling speed control device 23 to control the driving of DC motors L10, R11. Said operation is repeated successively to travel the moving car 1.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention relates to a mobile vehicle that runs autonomously, detects unknown obstacles within the travel area, avoids them, and reaches a target. The present invention relates to a travel control system for a mobile vehicle suitable for driving the mobile vehicle to a specified point.

(Background of the Invention) Conventionally, as a method for autonomously driving or guiding a moving vehicle at a moving target point 1, a plurality of transmitters are installed within the moving area of the moving vehicle and mounted on the moving vehicle. A receiver receives a signal from the transmitter and causes the moving vehicle to travel based on the direction information. The driving path,
It is stored in a storage device installed in the moving vehicle itself,
Based on the traveling route information, the current position and attitude angle of the vehicle, command values for vehicle speed and steering angle are calculated, and the vehicle travels along the set traveling route based on the command values. A method has been proposed for
issue.

JP-A-57-120118).

However, in the above-mentioned conventional method, taking into consideration various obstacles to signal transmission and reception and the fact that the placement of obstacles (objects) within the driving area is not always uniform, the above-mentioned conventional method cannot be used in the applicable driving area ( For example, indoors) is limited.

[Purpose of the invention]

An object of the present invention is to detect an obstacle within a travel area using an obstacle (object) detection device mounted on a moving vehicle, and to detect the position of the obstacle by using an obstacle (object) detection device mounted on a moving vehicle. An object of the present invention is to provide a traveling control system for a moving vehicle, which stores the information in a storage device and causes the moving vehicle to avoid the obstacles and travel toward a target point.

[Summary of the invention]

The outline of the traveling control method for a mobile vehicle according to the present invention will be explained below.

First, within the travel area where the mobile vehicle is placed, there are objects within the travel area (hereinafter referred to as obstacles, whose existence is initially unknown to the mobile vehicle), the position of the mobile vehicle itself, and the location of the vehicle itself. Set an arbitrary coordinate system to display coordinates such as attitude angle, moving target point, etc. Then, as will be described later, while the vehicle is traveling, an obstacle detection device mounted on the vehicle detects obstacles within the travel area, and a map is created while storing the coordinates of the obstacles in the storage device.

Next 1, initial position A1 of movement expressed in the above coordinate system
(A represents the position vector in the above coordinate system), the attitude angle θ11, and the moving target point AT
The position vector AT and the attitude angle OT of the vehicle are input to the storage device mounted on the vehicle.

Now, let's consider a route to move one moving vehicle from the initial point A1 to the target point AT while avoiding obstacles.

Display the route from point A1 to point AT as a position vector,
Ant (→ represents a vector. AL = A T-A
1), AIAT can be expressed as the sum of arbitrary vectors whose component is li and whose angle with the X-axis of the coordinate system is θi. That is, AIAT =:, Σzi
Heexp (joi) =11)l=1 Roar. In equation (1), the right-hand side is expressed in bar format, and j
indicates the imaginary unit. n is an arbitrary number of vectors.

In Equation (1), since li, θi, and n are arbitrary values, there are an infinite number of routes from point A1 to point AT, and similarly, by avoiding obstacles, from point A
There will also be an infinite number of routes leading to point T. Therefore, in order to determine a route from point A1 to point AT while avoiding obstacles, li, θi, and will have to be specified.

11 of equation (1) explained above. In view of the specific need for θt, n, the travel control method of the present invention sets in advance the unit movement distance of the moving vehicle, the distance increment bone and the angle increment amount used when searching for obstacles, as described later. , input it into the storage device installed in the moving vehicle, and when searching for a route,
Search for obstacles on the map while changing the above-mentioned distance increment and angle increment, using the linear circulation connecting point Ai and AT point as the base line until the moving vehicle reaches a certain point, Search for the next movement point Ai+1, which can be moved while avoiding obstacles and is away from the point At by the unit movement distance, then specify li and θi and drive, and then move to the point Ai++. Using the straight line Ai+tAT connecting points Ai+tAT and A-r as the base line, search for obstacles in the same way as above, determine the next movement point Ai+2, and move to the right+1. While driving by specifying θi+4, detect obstacles in the area while driving sequentially from point A1, store the coordinates of the obstacles in the storage device, and based on the 114 reports, the above theory The moving vehicle is made to travel from point A1 to AT.

[Embodiments of the invention]

Hereinafter, the uninvented travel control method will be explained by way of an example.

Fig. 1 is a plan view of a mobile vehicle to which the present invention is applied, and Fig. 2 is a side view of Fig. M1.

In the figure, 1f'i is a moving vehicle to which the route search method of this embodiment is applied. 2 is a vehicle body, and a straight line C-C is a center line that passes through the center of the moving vehicle 1 and is oriented in the direction of travel. A straight line S-8 is an axis of a wheel L3 and a wheel R4, which will be described later, and is perpendicular to the center line CC. 3 and 4 are wheels 2 and 4 fixed to a wheel axle L5 and a wheel axle R6, which will be described later, on the axis S-8 at positions equidistant from the center line CC. The diameters of the wheel L3 and the wheel R4 are equal to each other. 5 and 6 are a wheel axle and a wheel axle R supported by a bearing 7 and a bearing 8 fixedly installed on the vehicle body 2, and 9 is a wheel axle R supported by a wheel axle L5 and a wheel axle R6 fixedly installed on the vehicle body 2. It is a bevel gear. 10 and 11 are a DC motor L and a DC motor R for driving the wheel L3 and the wheel R4, respectively, and 12
This is a tachogenerator attached to the motor.

Then, the moving vehicle 1
When running, the speed is controlled.

Number 13 is a speed reducer attached to the DC motors T, 10 and DC motor R11, and 14 is a bevel wheel fixed to each output shaft, which meshes with the bevel gear 9. 15 is
The rotation axis is the wheel axis L5. These are rotary encoders (tachometers) connected to the car picture axis R6, and each measures the rotational speed of the car ML3 and the wheels R4. 16 is
This is an angular velocity meter side bag @ (rate gyro) that measures changes in the moving direction of the moving vehicle 10 (changes in attitude angle).

Reference numeral 17 denotes a speed control device (driver) that receives a speed command for travel control from a travel speed control device 25, which will be described later, and controls the rotational speeds of DC motor L10 and DC motor R11 to the command speed. Reference numeral 18 is an obstacle detection device (e.g., an ultrasonic pulse generator) that rotates to detect obstacles within the travel area and transmits distance information from the mobile vehicle 1 to the obstacles to a travel control device 22 (described later). This is an ultrasonic pulse transmitter/receiver that transmits and receives ultrasonic pulses. 19 is a low rotation motor that rotates the signal transmission/reception unit 188 of the obstacle detection device 18; 20 is connected to the shaft of the low rotation motor 19, and is connected to the base line of the mobile vehicle 1 (for example, straight line C- This is a tachometer (for example, a rotary encoder) for measuring the rotation angle of the transmitter/receiver 18a of the obstacle detection device 18 with respect to C). Reference numeral 21 denotes a support base that supports the obstacle detection device 18 described above, and is fixed to the center of the vehicle body 2. 22 has a function of receiving the wheel rotation speed information from the two rotary encoders 15 and the angular velocity information from the angular velocity measuring device 16 to determine the coordinates and direction (attitude angle) of the moving vehicle 1 while it is running; Receiving the distance information from the detection device 18 and the angle information from the tachometer 20, the coordinates of the position where the obstacle is located are determined and stored in the storage device 2 described later.
A function to execute and control a route search program that searches for a route to a target movement point by restoring the obstacle information (hereinafter referred to as map information) stored in the memory device ffi 22b and the memory device ffi 22b. and a travel control function that causes the vehicle to travel on a route to a target point determined by the program. 23 receives a speed command, a steering angle command 9, a start or stop command, etc. from the traveling control device fW22, and simultaneously outputs a wheel L3 and a wheel R from a rotary encoder 15 and a tacho generator 12.
This is a traveling speed control device that receives rotation speed information of No. 4 and controls the rotation speeds of DC motor L10 and DC motor R11. 24 is a storage battery serving as a power source, and 25 is a caster attached to the vehicle body 2.

The above is the configuration of the moving vehicle 1.

Next, the configuration and functions of the control in the moving vehicle 1 will be explained below with reference to FIG. 5.

FIG. 3 is a control block diagram showing the control configuration of the mobile vehicle 1. As shown in FIG. In the figure, the aforementioned traveling control device 22 includes a microprocessor (central processing unit) 22a and a memory (
It consists of a storage device) 22b and an interface (input/output signal processing circuit) 22c. Similarly, a traveling speed control device 23, a microprocessor 23a,
It is composed of a memory 23b and an interface 23c. 26Vi, input the initial position of mobile vehicle 1, the coordinates and attitude angle at the target point of movement,
This is the keyboard (operation panel) used to turn on and off the power.

The travel control of the mobile vehicle 1 is performed by the travel control device 22.
The coordinates, attitude angle, and obstacles of the current location and the pre-stored target movement point are detected by the obstacle detection device 18, and using the map information stored in the memory 22b, as will be described later. Through the route search of the present invention, a movable character moving point toward a movement target point is searched, the character moving point is determined, and then steering is performed when moving from the current position to the character moving point. The angle and vehicle speed are determined, and the results are sent to the traveling speed control device 23 to drive and control the DC motor LIO and the DC motor R11.

Next, the travel control described above will be specifically explained using FIGS. 4 and 5. FIG. 4 is a route search explanatory diagram for explaining the route search included in the travel control system of the present invention, where the position Ai of the mobile vehicle 1 itself (i=
1.2. ....

T) and the attitude angle (azimuth) θ1 (i=1
．． 2. This is a coordinate system set to display the above attitude angle θ1, which is the straight line C in Fig. 1.
-Defined as the angle between C and the X axis. Reference numeral 27 is an obstacle located within the travel area and whose existence is completely unknown to the mobile vehicle 1 at the beginning. FIG. 5 is a flowchart of control while the mobile vehicle 1 is traveling. Note that 5 shown in Figure 5
t(i==1.2, 5...) indicates each step of the flowchart. Further, the flowchart is performed at a predetermined time period Δt.

The mobile vehicle 1 moves to the target point in the following order.

(1) In order to display the position [Ai of the moving vehicle 1 and the attitude angle θi at that position, a coordinate system X-0-Y is set. The coordinate system is set by the traveling control device 22 of the moving vehicle 1, with the initial point A1 before the start of movement as the origin O, the straight line C-C shown in FIG. 1 as the Y axis in the direction of travel, and the straight line S. −
8 on the X-axis, or by presetting and inputting and storing the memo '122bi' of the travel control device 22. The following explanation will be based on the latter.

(2) Search radius R of 10 moving vehicles used when searching for obstacles 27 and required radius R as the size of moving vehicle 10
8, the distance increment Δl and the angle increment 1 . Δα and Memo 1J22
(3) The coordinates of the initial point Ai and the moving target point AT of the mobile vehicle 1, 'j l + AT, and the attitude angle θ1. θT is input from the keyboard 26 and stored in the memory 22b (Sl).

(4) First, it is checked whether the route search, that is, the number of searches i for the personal movement point Aj+1, exceeds N times set in advance as the upper limit number of times to travel through the moving target point AT (Sl). . If it exceeds the limit, it is assumed that there is no route, issue a stop command, and move! Stop it 1 and end it (connector (of).

(5) The mobile vehicle 1 uses the travel control device 22 to
The coordinates of Ai, which is the vehicle's current location, and the attitude angle θi of the mobile vehicle 1 are measured and stored (S3). The measurement is carried out using the rotary encoder 15 shown in FIG. 3, where Δ is the amount of movement within time, and using the angular velocity measuring device 16, Δ is the angular variation within time.
This is done by measuring each and sending the information through the interface 22c to the microprocessor 22a, where it is subjected to arithmetic processing.

'6) Next note! It is checked whether the moving target point AT stored in j22b and the current point At of the moving vehicle 1 are equal (S4). If they are equal, it is assumed that the target point AT has been reached, and the attitude angle is set to 0.
It is stopped and finished (S5゜connector ■).

(7) As the next step, obstacles 27 in the driving area
Search for. To detect the obstacle 27 and store it in the memory 22b, the travel control device 22 receives the distance information between the moving vehicle 1 and the obstacle 27 from the first day of the obstacle detection device and the angle information from the tachometer 20. This is done by importing the data, performing arithmetic processing on the microprocessor 22a, and storing the result in the memo 1J22b (S6).

(8) And a memo! On J 22b, find the vector AT connecting the current point Ai of the moving vehicle 1 and the moving target point AT, and find its component AiA7 and the angle αi that ↑ to A makes with the X axis. Next, the ratio of AiA to early movement radius R9 and required radius l phase is softened, and if AiAT≧(R-R3), then unit movement distance ej is 1i=(R-Rs), otherwise , Ji=AiAr (S79° After passing through the steps above (9), V, Hashiraji Deep Purple, and the resulting running are performed as follows.

(a) Memo IJ22b) of the travel control device 22 Based on the accumulated map information, point f in the direction αi determined in (8), and move on the tangent line tangent to the circle l of the required radius at the point of contact (in Fig. 4). , if the angular increment Δα is a positive value, it is 81 points, and if it is a negative value, it is an-1 point), search for the obstacle 27 while increasing the distance increment Δl, and search for the obstacle 27. If not, the above tangent line is searched (Ss, S+o, Sr1.
S12).

(b) Next, if the obstacle 27 was not searched in (a), considering that the size of the moving vehicle 1 is a circle with the required radius Rs, it is possible to move towards the αi direction with a width of 2 Rs The space of is defined as the tangential surface (if Δα is positive) or the tangent Ha H−
pad (when Δα is negative) as the baseline, and obstacle 2
Search for 7. That is, as shown in FIG. 4, in the αi direction l, a point a3 + &5 + with a required radius Rs
”・y From all−1, each unit movement distance li
The search for the obstacles 27 is performed sequentially up to the point a4+85+...+ all, which is a distance of
+o + S++ + 812).

(C) As a result of the search in (a) and (b), if there is no obstacle 27, the angle is αi and Δi from the point At.
A point [Aid] which the mobile vehicle 1 can move to can be determined. In addition, as the traveling direction of moving vehicle 1),
αi can be determined.

(d) If the presence of the obstacle 26 is detected during the searches in (a) and (b) above, the search is aborted at that point, and if the angular increment Δα is positive,
(αi+Δα), if Δα is negative, (αi−1Δα1)
The same search as in (a) and ib) is performed in the direction of . As a result, if the obstacle 27 is long, (c)
In the same way as i-koyoru, (αl+Δα) can be determined as the point of motion of the person Ai+1 and the direction of movement (S+ 3.s
e). On the other hand, if the obstacle 27 is captured, in the same way as above, the angle increment amount Δα is further increased to obtain (αi+
2Δα) direction.

By repeating the above search, the next point A that the mobile vehicle 1 can move to in order to move from the current point Ai to the target point AT.
i +1 and the direction of travel of the mobile vehicle 1 can be determined. Then, the moving vehicle 1 travels with the personal movement point Ai++ as the target point (Be, S+ 4. Connector ■). Traveling is performed by sending a steering angle and a travel command from the travel control device fR22 shown in FIG. 5 to the travel speed control device @25. The steering angle is given by the value obtained by subtracting the traveling direction αi from the attitude angle θi.

(e) If (d) is searched for, obstacle 27
If the angular increment amount Δα is positive and the value of the addition amount Δθ exceeds an arbitrarily set angle (180° in the description of the present invention), the angular increment amount is calculated from the current point Ai. The addition amount Δθ of the quantity Δα is added (αi+Δ0
) direction, the memo 1J22b stores that the route is not blocked by 271 obstacles (ΔθL is set to 1),
Newly set the angle increment Δα to a negative value and search for the next movement point Ai++ (Ss+S+s ls+613
171SI81 connector ■). When the angular increment amount Δα is negative and there is no route (ΔθR is set to 1), contrary to the above, Δα is replaced with a positive value and Ai++ of the next movement point is set.
Search (581SL5151915201 S2
1 + Connector ■) 0 Then, at the current point Ai, the above search is performed, and if the next moving point Ai++ is determined, the traveling of the moving vehicle 1 is continued in steps S91 to S14. When the angle increment amount Δα is negative as well as when it is positive, if the next movement point Aids cannot be determined (both ΔθL and ΔθR are 1), the route from the current point Ai to the movement target point AT is blocked by the obstacle 27. is detected, it is treated as not existing, the moving vehicle 1 is stopped, and the process ends (S'
s.

Say + S22 + S23 or S19 + S
20! Connector ■, S22 T 823).

In addition, in the search for the next t8 moving point Ai+1, if the absolute value IΔ01 of the addition amount of Δα does not exceed 180°, Δα
Search and run without changing the sign of 1Δθ1 is 1
When the angle exceeds 80°, the sign of Δα is changed and the vehicle is searched and run.

(f) The above-described search for the next moving point Aids and driving to that point are repeated at a period of Δt, and the moving vehicle 1 is made to move to the target point AT while avoiding the obstacle 27 (b9+ SI4 + conjunction ■).

When the mobile vehicle 1 reaches the target point AT, it assumes a posture at a predetermined posture angle θT and stops.

End (S4.Ss, connector ■+ 5221523
).

FIG. 4 shows an example of a travel route determined by the vehicle travel control system of the present invention including the route search described above. From the ω period point A+, the angular increment amount Δα is increased by the positive ζ, and the target point A is reached.
The next movement point is sequentially searched until T, and the determined route is A+
'-Ai-t A1-A1.1-Al1 A12-
This is the locus indicated by -AT. The angle increment from the initial point A1 is set to a negative value (thus, the next movement point to the target point AT is searched, and at point A23, the absolute value 1Δθ1 of the addition amount of the angle increment Δα exceeds 180°, so Δα is The route found by sequentially searching for the next movement point is At
-Ai-t -Ai-Ai+1-A21 A22
A23 A22 A21 A24 A25-・
...-A30 This is the trajectory indicated by AT.

In the traveling control method for a moving vehicle of the present invention described above,
Search distance radius R5 unit movement distance li and distance increment view Δl used in searching for obstacles.

Angle increment amount Δα, its positive/negative value, addition amount of angular increment amount 1Δθ
upper limit of 1, execution cycle Δt of the travel control flowchart,
The upper limit N1 of the number of searches is determined by the traveling speed of the mobile vehicle 1,
These values are selected in consideration of control responsiveness and accuracy for the required travel route. In addition, in the embodiment of the present invention, the obstacle detection device 18 is mounted on the moving vehicle 1 to detect an unknown obstacle 27 and detect the unknown obstacle 27 in the memory 22b.
However, this is not limited to the above, when the position of the obstacle 27 is known, without using the obstacle detection device 18, it is possible to run while avoiding the obstacle 27. ° By storing the position of obstacles in the driving area in the ROM of Memo 1J18b, you can avoid obstacles and
The moving vehicle 1 can also be caused to travel toward a target point AT.

As described above, according to this embodiment, it is possible to drive and guide the mobile vehicle to the target movement point while avoiding unknown obstacles.

〔Effect of the invention〕

As explained above, according to the present invention, there is no need to arrange a transmitter or the like as a reference point within the travel area of a moving vehicle, and the position of an obstacle within the travel area is input into a memory or the like in advance. Since the route of the moving vehicle to the target point can be searched and the traveling direction of the moving vehicle can be determined while the vehicle is traveling, the traveling control method of the moving vehicle of the present invention can be applied to any driving area. be.

[Brief explanation of drawings]

FIG. 1 is a plan view of a moving vehicle to which the moving vehicle running control system of the present invention is applied, FIG. 2 is a side view of the moving vehicle shown in FIG. 1, and FIG. 5 is a running control configuration of the moving vehicle. FIG. 4 is a route search explanatory diagram for explaining the route search included in the present invention, and FIG. 5 is an execution flowchart of travel control. 1...#h car 10...Progressive motor L11
... Hundred current motor R 15 ... Rotary encoder 16 ... Angular velocity meter side bag + ft 17 ... Speed control device 18 ... Obstacle detection device 22 ... Travel control device 25 ... Travel speed Control device (Fig. 1, Fig. 2, Fig. 3), Fig. 4, Fig. 2

Claims (1)

[Scope of Claims] 1. In a mobile vehicle, a unit movement distance, a distance increment, an angular increment, and an upper limit value of the addition amount of the angular increment, which are set for searching for obstacles in a driving area; The target movement point of the moving vehicle is input and stored in a storage device mounted on the moving vehicle, and an obstacle detection device mounted on the moving vehicle searches for obstacles within the driving area and locates the obstacles. Sequentially, the information stored in the storage device is stored in the storage device, and based on the information in the storage device, a circle centered on the current location of the moving vehicle and having the radius of the unit travel distance is defined as the current location of the moving vehicle and the above. Search for obstacles by adding or subtracting the above distance increment and angle increment based on the straight line connecting the target movement points of Determine the direction of travel when moving to the point,
A travel control method for a mobile vehicle, characterized in that the vehicle is caused to travel by sequentially running the vehicle from an initial point to a target travel point. 2. If the amount of addition or subtraction of the angular increment amount exceeds the upper limit value set in advance and stored in the storage device, change the value of the angular increment amount from positive to negative or from negative to positive, 2. The traveling control system for a moving vehicle according to claim 1, wherein an obstacle is searched for and a next moving point is searched for.