A method for enabling determination of non-movement of a train before opening a door

Abstract

This invention discloses a method for determining whether a train is no longer moving before enabling door opening, comprising: step S1, acquiring the train's motion state; step S2, determining whether the train is stationary; if the train is stationary, proceeding to step S3; step S3, acquiring the train's traction command state within a "traction command delay" time window; step S4, determining whether a traction command has been applied; if a traction command has been applied, proceeding to step S5; step S5, acquiring the traction force magnitude of the traction command state during this period; step S6, determining whether the traction force magnitude during this period is higher than an adhesion threshold; if it is higher than the adhesion threshold, proceeding to step S7; step S7, acquiring the time difference between the most recently applied traction command higher than the "adhesion threshold" and the current time; step S8, determining whether the difference exceeds the "traction command delay"; if so, the train is considered no longer moving. This avoids train shaking or movement caused by residual traction force that may be en route.

Description

Technical Field

[0001] This invention relates to the field of urban rail transit signaling technology, specifically a method for determining that a train is no longer moving before enabling door opening. Background Technology

[0002] Existing technology only checks whether the current conditions are met before the train doors open, without considering whether the train's previously accumulated kinetic energy has been exhausted. This could lead to situations where the train is shaking or even moving while the doors are opening. Examples include situations where the train was previously applying secondary traction but has not yet responded (traction command is en route), and the door opening conditions are just met at this moment; and situations where the train waits too long for the brakes to be fully applied. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of existing methods and provide a method that enables the determination that the train is no longer moving before the doors are opened, thereby avoiding train shaking or movement caused by residual traction forces that may be in transit.

[0004] The technical solution to achieve the above objectives is:

[0005] A method for determining that a train is no longer moving before opening a door includes:

[0006] Step S1: Obtain the train's motion status;

[0007] Step S2: Determine whether the train is stationary. If the train is stationary, proceed to step S3. If the train is not stationary, wait until the train comes to a stop before proceeding to step S3.

[0008] In step S3, the traction command status of the train within the "traction command delay" time window is obtained.

[0009] Step S4: Determine whether a traction command has been issued. If a traction command has been issued, proceed to step S5.

[0010] In step S5, the magnitude of the traction force in the traction command state at this time is obtained;

[0011] Step S6: Determine whether the magnitude of the traction force is higher than the adhesion threshold. If it is higher than the adhesion threshold, proceed to step S7.

[0012] In step S7, the time difference between the most recently applied traction command that is higher than the "adhesion threshold" and the current time is obtained.

[0013] Step S8: Determine whether the difference exceeds the "traction command delay". If not, return to step S1 and reacquire the traction command status of the train in the past period. If so, it is considered that the train is no longer moving.

[0014] Preferably, in step S4, it is determined whether a traction command has been applied. If no traction command has been applied, the train is considered to no longer be moving.

[0015] Preferably, in step S6, when the train is running on a straight track, the traction force threshold Fs is obtained by first calculating the wheel-rail adhesion coefficient measurement value, and the calculation method is as follows:

[0016] Ψ′=(fm*a) / m;

[0017] Where Ψ′ is the measured value of the wheel-rail adhesion coefficient, f is the magnitude of the dynamic output traction force of the train, m is the actual wheel-rail vertical load, and a is the actual acceleration of the train.

[0018] Preferably, the measured wheel-rail adhesion coefficient is obtained by using a moving average method to get the adhesion coefficient value Ψ, and then the traction force threshold Fs is calculated using the following formula:

[0019] Fs = Ψ * m.

[0020] Preferably, in step S6, the condition for the train to be stationary is: the train is stationary and the magnitude of the traction force f of the train has always been less than the annual adhesion threshold Fs over a period of time.

[0021] The beneficial effects of this invention are: by judging whether a traction command has been applied, whether the force exceeds the adhesion threshold, and whether the traction command delay has been exceeded for a stationary train over a period of time, as long as the train's traction force does not exceed the adhesion threshold, there is no need to judge whether the traction command delay has been exceeded. As long as the time difference between the most recently applied traction command that exceeds the adhesion threshold and the current time exceeds the traction command delay, it can be determined that the train is no longer moving; thus avoiding train shaking or movement caused by residual traction force that may be en route. Attached Figure Description

[0022] Figure 1 This is a flowchart of a method for determining whether a train is no longer moving before opening a door, according to the present invention. Detailed Implementation

[0023] The technical solution of the present invention will now be clearly and completely described in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] The invention will now be further described with reference to the accompanying drawings.

[0025] like Figure 1 As shown, a method for determining that a train is no longer moving before opening a door includes:

[0026] Step S1: Obtain the train's motion status.

[0027] Step S2: Determine if the train is stationary. If the train is stationary, proceed to step S3. If the train is not stationary, wait until the train comes to a stop before proceeding to step S3.

[0028] Step S3: Obtain the traction command status of the train within the "traction command delay" time window.

[0029] Step S4: Determine whether a traction command has been issued. If a traction command has been issued, proceed to step S5.

[0030] In this embodiment, it is determined whether a traction command has been issued. If no traction command has been issued, the train is considered to be no longer moving.

[0031] Step S5: Obtain the magnitude of the traction force in the traction command status at this time.

[0032] Step S6: Determine whether the magnitude of the traction force is higher than the adhesion threshold. If it is higher than the adhesion threshold, proceed to step S7.

[0033] In this embodiment, when the train is running on a straight track, the traction force threshold Fs is obtained by first calculating the wheel-rail adhesion coefficient measurement value, which is calculated as follows:

[0034] Ψ′=(fm*a) / m;

[0035] Where Ψ′ is the measured value of the wheel-rail adhesion coefficient, f is the magnitude of the dynamic output traction force of the train, m is the actual wheel-rail vertical load, and a is the actual acceleration of the train.

[0036] In this embodiment, the calculated wheel-rail adhesion coefficient measurement value is used to obtain the adhesion coefficient value Ψ, and then the traction force threshold Fs is calculated using the following formula:

[0037] Fs = Ψ * m.

[0038] In the embodiment, the condition for the train to be stationary is: the train is stationary and the magnitude of the traction force f of the train has always been less than the adhesion threshold Fs over a period of time; otherwise, it is considered that the train may move again.

[0039] Step S7: Obtain the time difference between the most recently applied traction command that is higher than the adhesion threshold and the current time.

[0040] Step S8: Determine whether the traction command delay has been exceeded based on the current time difference. If not, return to step S1 and reacquire the traction command status of the train over a past period. If so, assume that the train is no longer moving.

[0041] By using this method, it can be confirmed that the train is no longer moving when the train doors open, thus avoiding train shaking or movement caused by residual traction forces that may be present during the journey.

[0042] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for determining whether a train is no longer moving before enabling door opening, characterized in that, include: Step S1: Obtain the train's motion status; Step S2: Determine whether the train is stationary. If the train is stationary, proceed to step S3. If the train is not stationary, wait until the train comes to a stop before proceeding to step S3. In step S3, the traction command status of the train within the "traction command delay" time window is obtained. Step S4: Determine whether a traction command has been issued. If a traction command has been issued, proceed to step S5. In step S5, the magnitude of the traction force in the traction command state at this time is obtained; Step S6: Determine whether the magnitude of the traction force is higher than the adhesion threshold. If it is higher than the adhesion threshold, proceed to step S7. In step S7, the time difference between the most recently applied traction command that is higher than the "adhesion threshold" and the current time is obtained. Step S8: Determine whether the difference exceeds the "traction command delay". If not, return to step S1 and reacquire the traction command status of the train in the past period. If so, it is considered that the train is no longer moving. In step S6, the condition for the train to be stationary is: the train is stationary and the magnitude of the traction force of the train over a certain period of time is... Always less than the adhesion threshold .

2. The method for determining that the train is no longer moving before enabling door opening, as described in claim 1, is characterized in that... In step S4, it is determined whether a traction command has been issued. If no traction command has been issued, the train is considered to be no longer moving.

3. The method for determining that the train is no longer moving before enabling door opening, as described in claim 1, is characterized in that... In step S6, when the train is running on a straight track, the traction force threshold is obtained. First, calculate the measured value of the wheel-rail adhesion coefficient. The calculation method is as follows: ； in, This is the measured value of the wheel-rail adhesion coefficient. The magnitude of the traction force dynamically output by the train. This represents the actual wheel-rail vertical load. This represents the actual acceleration of the train.

4. The method for determining that the train is no longer moving before enabling door opening, as described in claim 3, is characterized in that... The calculated wheel-rail adhesion coefficient was obtained by using a moving average method to get the adhesion coefficient value. , and then the traction threshold The calculation formula is: 。

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