JPH0584267B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fixed position stop control method for a vehicle, and in particular for a railway vehicle, detects the actual value of acceleration/deceleration and uses this to predict the stop position. The present invention relates to a fixed position stop control method for a vehicle that accurately stops a vehicle at a fixed position without impairing riding comfort by determining an optimum brake command value.

[Conventional technology]

Conventionally, as a fixed-position stop control method for a vehicle, a stop pattern of target speed with respect to distance is determined, a target speed is generated according to the actual value of distance (hereinafter referred to as "actual distance"), and a target speed is generated according to the actual value of distance (hereinafter referred to as "actual distance"). A tracking control method that matches the actual speed) and a brake notch selection method that determines the walking curve for each notch from the calculated value of the brake force and then determines the brake notch to be used according to the distance and speed are considered. There is.

The following control method will be explained based on FIGS. 1 and 2. A walking curve up to a stop is determined as a stop pattern using a brake force calculation value, etc. with respect to a distance to a stop target point, and this is stored in the ROM 1 in advance.

Each time the actual distance and actual speed to the target stop point are detected, the target speed corresponding to the actual distance is read from ROM1, and the brake command value is adjusted according to the difference from the actual speed to create a walking curve that is given in advance as much as possible. stop along. A method for calculating the brake command value from the difference between the target speed and the actual speed is PID control, which adds a proportional value, differential value, integral value, or a combination of these values of the difference between the actual speed and the target speed to the brake command set value. is common.

Furthermore, as seen in Japanese Patent Laid-Open No. 51-20308, a method is known in which, in addition to the difference between the target speed and the actual speed, a value proportional to the difference between the target deceleration and the actual deceleration is added to the brake command. There is.

Next, the brake notch selection method will be explained with reference to FIGS. 3 and 4. This is done by calculating the travel curve to a stop based on the calculated brake force value corresponding to the brake notch, and storing this in advance as a speed corresponding to the notch and distance. Each time the actual distance and actual speed are detected, the brake knock is read out from the ROM 3 and used as the brake command value.

[Problem to be solved by the invention]

Generally, railway vehicles use air brakes in the low speed range of 30 km/h or less, which uses air pressure to push the brake shoe through the brake cylinder and obtain braking force through frictional force. There may be variations in braking force for the same brake command value due to conditions such as individual differences in the brake system, and there may be a time delay of one to several seconds after the brake command is issued until the specified deceleration is actually reached. is common. For this reason,
With the tracking control method, it is very difficult to obtain good control characteristics and accurately stop the vehicle at the target stop point. Furthermore, in the brake notch selection method, if the calculated value of the brake force deviates from the actual value, the brake force may increase immediately before stopping.

SUMMARY OF THE INVENTION An object of the present invention is to provide a fixed-position stop control method for a vehicle that can solve the above-mentioned problems, avoid sudden changes in brake command values that are unfavorable in terms of ride comfort, and also be able to accurately stop a vehicle at a target stop point. shall be.

[Means to solve the problem]

In order to solve the above problems, the present invention provides a vehicle having a means for detecting the distance to the target stop point, a means for detecting speed and acceleration/deceleration, and a brake force control means. After outputting a brake command from a point in front of you, the actual values of the distance, speed, and acceleration/deceleration to the stop target point are detected at approximately regular intervals, the destination point is predicted from these values, and the predicted destination point and stop target point are predicted. If the difference between the predicted arrival point and the target stop point is within a certain range, the current brake command value will be output continuously, and if the difference between the predicted arrival point and the target stop point exceeds the above range, the brake will stop at the target stop point. The brake command value corresponding to the required deceleration is calculated from the correspondence between the brake command value and the actual acceleration/deceleration value.

〔Example〕

Regarding the first embodiment of the present invention, FIGS.
This will be explained based on the diagram. First, a brake command is output from a point a certain value before the target stopping point, and the actual distance L _R , the actual speed V _R and the actual acceleration/deceleration β _R are detected at approximately regular intervals. Assuming that the deceleration remains the same until the vehicle stops, the traveling distance until the vehicle stops is expressed as L=V _R ² /(2β _R ).

If ΔL ₁ ≦L−L _R ≦ΔL ₂ (1), where ΔL ₁ and ΔL ₂ are positive or constant values of zero, the current brake command value is connected.

If L-L _R <-ΔL ₁ or ΔL ₂ <L-L _R (2), the brake command value is changed. Assuming that the deceleration is proportional to the brake command value, the optimum brake command value can be determined by the following equation.

V=V _R −β _R Δt ……(3) L′=L _R −(V _R ² −V ₂ )/(2β _R ) ……(4) β=V ₂ /(2L′) ……(5 ) B _N = B _O・β/β _R ...(6) However, Δt is the time from when the actual distance, actual speed, and actual acceleration/deceleration are detected until the new brake command value is output, and L' is the current actual The difference between the distance L _R and the distance traveled when traveling from the current actual speed V _R to the current actual acceleration/deceleration β _R for a time Δt, β is the deceleration required to stop at the target stop point, and B _O is The current brake command value, B _N , is the optimum brake command value.

Next, the second aspect of the present invention described in patent claim 2
An example of this will be explained based on FIG. If the brake command value cannot be a continuous value, the brake command value will be a discrete value corresponding to the brake notch command, and as in the first embodiment, the brake command value will determine the deceleration necessary to stop at the target stop point. It is not always possible to do so. In such a case, the predicted acceleration/deceleration value for each brake command value is corrected from the predicted acceleration/deceleration value corresponding to the brake command value and the actual acceleration/deceleration value, and then the corrected acceleration/deceleration predicted value is used to determine the stop target point. It is possible to stop the vehicle at a fixed point by determining the brake command value and its duration so that the brake command value reaches .

First, from the actual acceleration/deceleration β _R for the brake command value B _O corresponding to the current brake notch, the predicted deceleration value β _i for the brake command value B _i corresponding to each brake notch is predicted using the following equation.

β _i = B _i /B _O *β _R ...(7) Next, find the deceleration β required to stop at the target stop point in the same way as in the first example, and find the deceleration β that is greater than β and closest to β. Find the brake command value B ₁ for deceleration β ₁ and its brake notch BN ₁ . In this case, to give an example of how to stop at the target stop point using coasting and brake notch BN ₁ , the brake distance L ₁ from the speed V is L ₁ = V ₂ / (2β) ...(8) Therefore, it is only necessary to coast for the time Δt ₁ = (L−L ₁ )/V (9). In other words, in the first embodiment, the brake command value B N is output Δt seconds after detecting the actual distance, actual speed, and actual acceleration/deceleration, whereas in the second embodiment, the brake command value B _N is output only Δt ₁ second after Δt seconds. Just command brake notch BN ₁ after coasting.

In the above two embodiments, the time delay in brake operation relative to the brake command value was ignored, but it is possible to take the time delay into consideration in the above calculation. For example, if the delay time is Δt ₂ , use equation (3) to convert Δt to Δt
+Δt ₂ may be used.

〔Effect of the invention〕

According to the present invention, it is possible to accurately stop a vehicle at a target stop point without impairing ride comfort due to sudden changes in braking force.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing the stop pattern and control status of the conventional tracking control method, Fig. 2 is a block diagram of the above tracking control method, and Fig. 3 is a diagram showing the stop pattern corresponding to the brake notch of the conventional brake notch selection method. FIG. 4 is a block diagram of the brake notch selection method described above, FIG. 5 is a diagram showing a stop pattern corresponding to the brake notch of the present invention, and FIG.
FIG. 7 is a control flow diagram of the embodiment of the present invention.
FIG. 3 is a control flow diagram of an embodiment of the invention. 1...ROM, 2...Control gain, 3...ROM.

Claims (1)

[Scope of Claims] 1. In a vehicle having a means for detecting the distance to a target stop point, a means for detecting speed and acceleration/deceleration, and a means for controlling brake force, a brake command is issued from a point a certain value before the target stop point. After outputting, the distance to the target stop point,
Detects the actual values of speed and acceleration/deceleration, predicts the destination point based on these values, and continues outputting the current brake command value if the difference between the predicted destination point and the target stop point is within a certain range. If the difference between the predicted destination point and the target stop point exceeds the above range, calculate the necessary deceleration necessary to stop at the target stop point, and calculate the necessary deceleration from the correspondence between the brake command value and the actual acceleration/deceleration value. A fixed position stop control method for a vehicle characterized by calculating a brake command value corresponding to speed. 2 Correct the predicted acceleration/deceleration value for each brake command value from the predicted deceleration value and actual acceleration/deceleration value corresponding to the brake command value, and then use the corrected predicted acceleration/deceleration value to reach the target stop point. A fixed position stop control system for a vehicle according to claim 1, characterized in that a brake command value and its duration are determined.