JP2696724B2 - Automatic traveling system for traveling vehicles - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an automatic traveling system for automatically traveling a traveling vehicle in a set direction.

[Conventional technology]

As an automatic traveling system for traveling vehicles, a system that automatically travels along the electromagnetic cables and reflection tape while detecting electromagnetic cables and light reflective tape laid on the traveling path, traveling speed, traveling direction, The current position is detected by the detecting means, the detected value is compared with a set value,
There are known systems that automatically control the travel by controlling the travel so as to correct the difference.

[Problems to be solved by the invention]

The former automatic traveling system cannot be used outdoors because the installation of the electromagnetic cable is troublesome and the change of the traveling direction is troublesome, or the light reflecting tape becomes inoperable if it becomes dirty.

On the other hand, the latter problem can be solved by the latter automatic driving system.
A system in which several positions along a traveling direction to be traveled are stored as XY coordinates in a memory of a computer, and travel control is performed so as to pass through the stored position based on a current position of the traveling vehicle detected by a detection unit. Specifically, as shown in FIG. 4, the traveling control is performed along the straight line B connecting the adjacent positions A ₁ , A ₂ among the many positions A ₁ , A ₂ , A ₃ ,. If the traveling direction of the traveling vehicle deviates even slightly from the straight line B, the steered wheels are steered, and steering of the steered wheels becomes frequent, and smooth traveling control cannot be performed.

Therefore, an object of the present invention is to provide an automatic traveling system for a traveling vehicle that can solve the above-described problem.

[Means and actions for solving the problem]

The present invention relates to a speed detecting means 4 for detecting a speed of a vehicle based on a rotation speed and a driving wheel diameter of a driving wheel 2, a direction detecting means 5 for detecting a direction of the vehicle, and a position detecting means 6 for detecting a position of the vehicle. A traveling vehicle that stores the target position of the vehicle as XY coordinates in the computer 7 and stores the speed and the direction of the vehicle at the target position, respectively. Detected speed and direction detecting means 5
The X-axis component and the Y-axis component of the combined acceleration of the current lateral acceleration and the longitudinal acceleration of the traveling vehicle are calculated based on the direction detected by the position detection unit 6 and the current position detected by the position detection unit 6, and the operation is performed based on the calculated values. An automatic traveling system for a traveling vehicle, wherein a steering angle of a steering wheel and a longitudinal acceleration are obtained, and a steering angle of a steering wheel, an accelerator, and a brake are controlled to automatically travel toward a target position stored in a computer 7. It is.

As a result, the control factor input of the steering angle increases, so that the degree of freedom of the control gain is increased, and the traveling control can be smoothly performed toward the target position.

〔Example〕

As shown in FIG. 2, the traveling vehicle C includes a vehicle body 1 and driving wheels 2
And the steered wheels 3. The steered wheels 3 are steered to change the traveling direction. The traveling vehicle C is provided with speed detecting means 4, direction detecting means 5, and position detecting means 6. 7 is provided.

The speed detecting means 4 is for calculating a speed from a detected value of a rotation sensor for detecting the number of revolutions of the driving wheel 2 and a driving wheel diameter, and the direction detecting means 5 is, for example, a gyro compass, and The means 6 calculates the current position as XY coordinates from the speed and direction.

As shown in FIG. 3, a target position is input as XY coordinates into the memory 8 of the computer 7, and the azimuth and speed of the vehicle at that position are stored. The CPU 9 calculates the target position azimuth and speed based on the detected speed, direction, and current position based on the brake 10 and the engine output control means 1.
1, brake amount command, engine output command to steering means 12,
Each steering angle command is output.

 Next, the traveling control will be described with reference to FIG.

The case where the traveling vehicle at the position shown by the solid line in FIG. 1 travels to the target position as shown by the virtual line will be described.

First, the target position is stored in the memory 8 of the computer 7 as X.
-Stored as Y coordinate (0,0), velocity as V ₀ , azimuth as zero degrees. Here, the azimuth zero degree means traveling in the X-axis direction.

On the other hand, the current speed V, azimuth θ, and position (x,
y) is detected by each of the detection means and input to the CPU 9.

Based on these conditions, the steering angle 輪 of the steered wheels 3 is determined as follows.

The X-axis and Y-axis components V _x and V _y of the velocity V are given by V _x
= Vcosθ, given by V _y = Vsinθ, traveling the vehicle steering wheel 3
The lateral acceleration α _s is operated by operating the left and right sides, and the longitudinal acceleration α ₁ is exerted by operating the engine output control means 11 and the brake 10 to accelerate and decelerate, and the relationship between the lateral acceleration α _s and the steering angle ζ Becomes Here, 1 is a wheel base.

Assuming that the X-axis and Y-axis components of the resultant acceleration α of the longitudinal acceleration α _s and the longitudinal acceleration α ₁ are α _x and α _y , α _x = α _l cos
θ−α _s sin θ, α _y = α _l sin θ + α _s cos θ.

On the other hand, the equation of motion of the traveling vehicle is As is well known, α _x = − ｛k ₁ x + k ₂ y + k ₃ (V _x −V ₀ ) + k ₄ V _y ｝ (1) α _y = − ｛k ₅ x + k ₆ y + k ₇ (V _x −V ₀ ) + k ₈ V _y ｝... (2) that can be controlled by performing the feedback. Given α _x and α _y , the above equations (1) and (2) are solved, and ζ and α _l Therefore, α _x and α _y are calculated based on the detected speed, azimuth, and position, and ζ and α _l are obtained based on the calculated _values to determine the steering angle の of the steered wheels 3.

Here, in order to determine k _{1 to} k ₈ , J = C ₁ x ² + C ₂ y ² + C ₃ (V _x −V ₀ ) ² + C ₄ V ² _y + C ₅ αx ² + C ₆ αy ² (3) Is determined, and k ₁ to k ₈ are selected so as to mathematically minimize the evaluation function.

C comes to quickly reach to the C ₁ -C ₆ the response of the traveling vehicle is changed by adjusting the (3) wherein C ₁ -C ₂ largely them if target position as seen from the form of the formula _The azimuth θ quickly approaches zero when C ₃ and C ₄ are increased, and the steering angle of the steered wheels 2 is reduced to decrease the acceleration when C ₅ and C ₆ are increased.

As described above, since the steering angle and the speed are controlled based on the position and speed components of the traveling vehicle C in the X-axis and Y-axis directions, the control factor input becomes 4 and the degree of freedom in obtaining the control gain is large. In addition to smooth running control, desired characteristics can be obtained for control characteristics such as azimuth, acceleration, and steering angle.

〔The invention's effect〕

Since the control factor input of the steering angle increases, the degree of freedom in how to set the control gain increases, so that not only the traveling control can be smoothly performed toward the target position, but also the control characteristics can be set to desired values.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a traveling control operation showing an embodiment of the present invention,
FIG. 2 is an explanatory view of a traveling vehicle, FIG. 3 is a control circuit diagram, and FIG.
The figure is an explanatory view of a conventional example. 1 is a vehicle body, 2 is a driving wheel, 3 is a steering wheel.

Claims (1)

(57) [Claims] 1. Speed detecting means 4 for detecting the speed of a vehicle based on the number of rotations of the driving wheels 2 and the diameter of the driving wheels, direction detecting means 5 for detecting the direction of the vehicle, and position detecting means 6 for detecting the position of the vehicle. And a computer 7, wherein the computer 7 stores the target position of the vehicle as XY coordinates, and stores the speed and the direction of the vehicle at the target position, respectively. The X-axis component and the Y-axis component of the combined acceleration of the current lateral acceleration and the longitudinal acceleration of the traveling vehicle are calculated based on the speed detected by the above, the direction detected by the direction detecting means 5 and the current position detected by the position detecting means 6. The steering angle and the longitudinal acceleration of the steered wheels are obtained based on the calculated values, and the steering angle of the steered wheels, the accelerator, and the brake are controlled to automatically drive the vehicle toward the target position stored in the computer 7. An automatic traveling system for a traveling vehicle, characterized in that the traveling is performed.