CN111608522A - Sensor system for detecting platform door obstacle and detection method thereof - Google Patents

Abstract

The invention discloses a sensor system for detecting obstacles on a platform door and a detection method thereof, wherein the sensor system comprises a plurality of sensor groups which are uniformly arranged on one side of the platform door close to the running side of a train; each sensor group comprises 2 photoelectric sensors; the photoelectric sensor is arranged along the direction vertical to the platform door, and the detection distance along the direction vertical to the platform door is equal to the vertical distance between the platform door and the train; the sensor group is connected with the embedded chip and is used for processing input signals of the photoelectric sensor; when any sensor detects an obstacle, the sensor group outputs a high level. The method comprises the steps of detecting the triggering sequence of the photoelectric sensor group in each time period from the arrival to the departure of a train, correctly judging whether an obstacle exists between a train door and a platform door or not when the triggering sequence deviates from the normal triggering sequence, and sending a control instruction by an embedded chip to realize obstacle detection and train door opening and closing state monitoring.

Description

Sensor system for detecting platform door obstacle and detection method thereof

Technical Field

The invention relates to the technical field of obstacle detection, in particular to a sensor system for detecting obstacles of a platform door and a detection method thereof.

Background

In order to avoid accidents, most subways mainly depend on a driver to drive to advance for manual lookout, the luminous lamp strip of the tail of the vehicle is watched through the head manually, and whether pedestrians are clamped or foreign matters invade in the middle area or not is judged according to the integrity of the lamp strip. However, in a narrow and long area of more than 100 meters, it is difficult to judge by only manual means, firstly, the requirement for the driver's eyesight is high, and secondly, the driver is easily fatigued, so that the driver can make misjudgment due to subjectivity. In fact, some subway platforms adopt a curve platform, so that a driver cannot judge by looking out the tail of the vehicle through a head of the vehicle. In addition, the gap between the shielding door and the vehicle body is reduced by installing the rubber strip and the flexible baffle on the side, close to the track, of the shielding door of part of the subway, and passengers are prevented from sinking into the gap due to unexpected feet. The method can prevent people from being trapped to a certain extent, but the method cannot detect small objects which bring potential safety hazards in driving, has no alarm prompting function and only can prevent the shielding door from being closed. Therefore, the research on the foreign matter intrusion detection between the subway platform train and the screen door is helpful for assisting a driver to perform safety detection before driving, can effectively guarantee the life safety of passengers, and is also helpful for reducing the operation cost.

Disclosure of Invention

The purpose of the invention is as follows: the invention provides a sensor system for detecting obstacles on a platform door and a detection method thereof.

The technical scheme is as follows: in order to achieve the purpose, the invention adopts the technical scheme that:

a sensor system for detecting obstacles on a platform door comprises a plurality of sensor groups which are uniformly arranged on one side of the platform door close to the running side of a train; each sensor group comprises 2 photoelectric sensors; the photoelectric sensor is arranged along the direction vertical to the platform door, and the detection distance of the photoelectric sensor along the direction vertical to the platform door is equal to the vertical distance between the platform door and the train; the 2 photoelectric sensors have the same coordinate relative to the running direction of the train, and form a hardware redundant structure; the sensor group is connected with the embedded chip and is used for processing input signals of the photoelectric sensor; when any sensor detects an obstacle, the sensor group outputs a high level.

Furthermore, the photoelectric sensor adopts a laser light source, and the diameter of a light spot is 2 mm.

An obstacle detection method using the sensor system for platform door obstacle detection includes the steps of:

step 1, a train arrival detection stage;

when a train enters a station, the sensor groups arranged on the platform door are sequentially triggered by the train body to output high level, and at the moment, the embedded chip acquires a high level signal; the sensor which is not triggered by the rising edge in the time period is judged to be in a fault state, the power supply of the sensor is cut off, and the other redundant sensor takes over the work;

step 2, a train door opening detection stage;

after the train enters the station, entering a door opening stage; when the train door is opened, the corresponding sensor group does not detect obstacles, the output signal is changed into low level, and the sensor group is changed into falling edge triggering; when the sensor groups corresponding to the train doors are triggered along the falling edge in sequence, the train doors enter an opening operation; when the sensor groups corresponding to the train doors are not triggered along the falling edge in sequence within the specified time, the embedded chip immediately sends an overtime door closing command; when the train door is opened, the sensors which are triggered for the last two times are triggered again, the embedded chip immediately sends out an obstacle alarm command, and meanwhile, the train door is closed;

step 3, detecting train door closing;

after the train door opening operation is finished, entering a door closing stage; at the moment, the sensor group corresponding to the train door sequentially detects obstacles, the output signal is changed into high level, and the sensor group is changed into rising edge triggering; when the sensor groups corresponding to the train doors start along the rising edge in sequence, the train doors enter a door closing operation; when the sensor groups corresponding to the train doors are not triggered along the rising edge in sequence within the specified time, the embedded chip immediately sends an overtime door closing command; when the train door is closed, the sensors triggered twice are triggered again, the embedded chip immediately sends out an obstacle alarm command, and meanwhile, the train door is closed;

step 4, a train outbound detection stage;

when the train leaves the station, the sensor groups are triggered along the falling edge in sequence, and when the sensor groups which are not triggered along the falling edge exist, the embedded chip immediately sends out an obstacle alarm command.

Has the advantages that: the invention judges the state of the train door according to the triggering sequence of the sensors. When at least three groups of sensors are triggered, the state of the train door can be judged, and the embedded chip sends out a control command. Meanwhile, whether the door opening and closing actions are finished or not is judged after a period of time. And if the fault occurs, immediately sending a door closing command. In the process of opening and closing the door, if the two groups of sensors are continuously triggered again, a door closing command is immediately sent.

Drawings

FIG. 1 is a layout view of a vehicle position and sensor set according to the present invention;

FIG. 2 is a schematic diagram of a train arriving at a station;

FIG. 3 is a schematic diagram of a train outbound;

FIG. 4 is a schematic diagram of a sensor configuration;

FIG. 5 is a schematic view of a sensor mounting location;

Detailed Description

The following provides a more detailed description of the present invention, taken in conjunction with the accompanying drawings.

According to the actual train operation requirement, the hardware design, the software design and the sensor arrangement are as follows:

hardware design:

in this embodiment, an STM32F107 chip is adopted, 15 IO ports are reserved, the number of the photoelectric sensors is 15, the sensors are composed of two diffuse reflection sensors with model numbers of OS10-AKL150CN6, and the sensor structure is shown in fig. 4. The X-axis coordinates of both sensors are the same. When the train door is opened and closed, the train door moves horizontally in the X direction, and does not move in the Y-axis direction, so that two position signals of each group of sensors for detecting the X axis are completely consistent. The two OS10-AKL150CN6 photoelectric diffuse reflection sensors form a hardware redundancy structure, and when any one of the sensors detects an obstacle, the sensor group outputs high level. The photoelectric sensor adopts a laser light source, the diameter of a light spot is 2mm, and the detection distance of the photoelectric sensor along the direction vertical to the platform door is equal to the vertical distance between the platform door and the train workshop.

Designing software:

this embodiment is programmed with keil5 and the photosensor triggers the high and low levels by detecting the presence or absence of an obstacle. And reading the high and low levels of the input port by calling a standard library function API GPIO-ReadInputDataBit, wherein the high level is 1, and the low level is 0. In order to ensure the processing speed, binary system is adopted for judgment, and all sensors are 1 if triggered, and all sensors are 0 if not triggered. And then carrying out sequence judgment according to the requirement of the scheme. The software adopts simple c language programming, judges the sequence through if, and sends out corresponding control signals.

The sensors are arranged as shown in fig. 5, the sensors are uniformly distributed in the area with the distance between the platform sliding door and the boundary being 30 mm-2240 mm, the sensors at two ends are respectively 30mm away from the boundary of the platform sliding door, the distance between the sensor groups is 160mm, and the serial numbers of the sensors are from left to right and are S1-S15.

According to the requirements related to train parking, the parking precision of the train is +/-350 mm. The left error is negative, the right error is positive, the error value is represented by delta D, the train stops at any position in a specified range, and the layout is shown in figure 1.

The following provides the detection results of the sensors of the system and corresponding processing schemes of the system in each time period from the arrival to the departure of the train:

(1) train arrival stage

Before the train enters the station, the sensor detects the obstacle-free object. When the train arrives, the train body will in turn trigger the sensors, as shown in figure 2.

The process can be used as a fault determination time period of the photoelectric sensor, when the sensors feed back signals according to the mode and the sequence, the fact that the train is entering the station can be determined, the sensor which is not triggered by the rising edge in the time period can be determined as a fault state, the power supply of the sensor is cut off, and the sensor is replaced by another redundant sensor to work.

(2) Train door opening stage

After the train stops in the prescribed area, the door center may be located at any position between S4 and S12, and when the door is opened, 10 sensor activation sequences are shown in table 1.

TABLE 1 train door opening stage sensor trigger sequence

When at least the first three groups of sensors are sequentially triggered as shown in the table 1, the embedded chip sends out a control command and continues to monitor the triggering state of the sensors; when the specified time is over, if the ten groups of sensors are not correctly triggered in sequence, a door closing command is immediately sent out; in the door opening process, the sensors which are triggered at the last two times are triggered again, and then a door closing command is sent immediately.

(3) Train door closing stage

Due to different train parking positions, there are 10 sensor trigger sequences when the door is closed, as shown in table 2.

TABLE 2 train door closing phase sensor trigger sequence

When at least the first three groups of sensors are sequentially triggered as shown in the table 2, the embedded chip sends a door closing command and continues to monitor the triggering state of the sensors; when the set time is over, if the ten groups of sensors are not triggered in a correct sequence, a door closing command is continuously sent out, and an alarm is sent out; in the door closing process, the sensors triggered at the last two times are triggered again, and then the embedded chip immediately sends out a door closing command and sends out an obstacle detection alarm.

(4) Train departure phase

As shown in fig. 3, when a train leaves the station, the sensor groups are triggered along the falling edge in sequence, and when the sensor groups which are not triggered along the falling edge exist, the embedded chip immediately sends out an obstacle alarm command.

The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the invention and these are intended to be within the scope of the invention.

Claims (3)

1. A sensor system for detecting platform door obstacles is characterized by comprising a plurality of sensor groups which are uniformly arranged on one side of a platform door close to the running side of a train; each sensor group comprises 2 photoelectric sensors; the photoelectric sensor is arranged along the direction vertical to the platform door, and the detection distance of the photoelectric sensor along the direction vertical to the platform door is equal to the vertical distance between the platform door and the train; the 2 photoelectric sensors have the same coordinate relative to the running direction of the train, and form a hardware redundant structure; the sensor group is connected with the embedded chip and is used for processing input signals of the photoelectric sensor; when any sensor detects an obstacle, the sensor group outputs a high level.

2. A sensor system for platform obstacle detection according to claim 1, wherein the photoelectric sensor employs a laser light source with a spot diameter of 2 mm.

3. An obstacle detection method using the sensor system for platform door obstacle detection according to claim 1, comprising the steps of:

step 1, a train arrival detection stage;

when a train enters a station, the sensor groups arranged on the platform door are sequentially triggered by the train body to output high level, and at the moment, the embedded chip acquires a high level signal; the sensor which is not triggered by the rising edge in the time period is judged to be in a fault state, the power supply of the sensor is cut off, and the other redundant sensor takes over the work;

step 2, a train door opening detection stage;

after the train enters the station, entering a door opening stage; when the train door is opened, the corresponding sensor group does not detect obstacles, the output signal is changed into low level, and the sensor group is changed into falling edge triggering; when the sensor groups corresponding to the train doors are triggered along the falling edge in sequence, the train doors enter an opening operation; when the sensor groups corresponding to the train doors are not triggered along the falling edge in sequence within the specified time, the embedded chip immediately sends an overtime door closing command; when the train door is opened, the sensors which are triggered for the last two times are triggered again, the embedded chip immediately sends out an obstacle alarm command, and meanwhile, the train door is closed;

step 3, detecting train door closing;

after the train door opening operation is finished, entering a door closing stage; at the moment, the sensor group corresponding to the train door sequentially detects obstacles, the output signal is changed into high level, and the sensor group is changed into rising edge triggering; when the sensor groups corresponding to the train doors start along the rising edge in sequence, the train doors enter a door closing operation; when the sensor groups corresponding to the train doors are not triggered along the rising edge in sequence within the specified time, the embedded chip immediately sends an overtime door closing command; when the train door is closed, the sensors triggered twice are triggered again, the embedded chip immediately sends out an obstacle alarm command, and meanwhile, the train door is closed;

step 4, a train outbound detection stage;

when the train leaves the station, the sensor groups are triggered along the falling edge in sequence, and when the sensor groups which are not triggered along the falling edge exist, the embedded chip immediately sends out an obstacle alarm command.

Images