TRAIN ANTI-COLLISION CONTROL METHOD

Abstract

ABSTRACT TRAIN ANTI-COLLISION CONTROL METHOD The present invention discloses a method to implement a train collision avoidance system which is a critical aspect of railway safety management. This system simulates a collision avoidance scenario using MATLAB, focusing on the behaviour of two trains traveling either in the same direction or in opposite directions. By dynamically adjusting train speeds based on their proximity and applying deceleration techniques when necessary, the simulation demonstrates how modern safety mechanisms can be implemented to ensure that trains maintain a safe distance from one another, effectively avoiding collisions. The simulation employs a time-step-based approach, where the position, speed, and distance between two trains are updated at each step. Key parameters such as initial speed, deceleration rate, stopping distance, and safe distance between trains are considered to create a realistic simulation. The invention highlights the importance of implementing automated train control systems in real-world railway networks to enhance safety and operational efficiency. (FIG. 1(a) and FIG. 1(b) will be the reference figures)

Specification

Description:TRAIN ANTI-COLLISION CONTROL METHOD

FIELD OF THE INVENTION
The present invention particularly relates to a train anti-collision control methodand belongs to the technical field of automobile safety.
BACKGROUND
Train collision avoidance is a critical aspect of railway safety, aimed at preventing accidents and ensuring the smooth operation of rail systems.
668/BOM/1999titled 'An anti-collision device systems for train like transportation system'comprises of a Network of Anti Collision Devices (ACD) provided at locomotives (LOCO ACD), guard vans (GUARD ACD) stations (STATION ACD) and Jevel crossing gates (GATE ACD) comprising of a microprocessor based Central Control Unit (CCU) (1), Radio Transceiver (2), Global Positioning System (GPS) receiver (3), Power Converter (4), Data entry key pad (5), Whip antenna (7) for radio transceiver and hard mount antenna (8) for GPS receiver, a Crew interface (9), Automatic Braking Unit (ABU) (6) linked with the braking mechanism of locomotive to control the speed of train as per command received from the CCU (1) all units and systems functionally interconnected to detect situations when collision or side collision of two moving ACDs may occur and take quick action to prevent the same or drastically reduce the seriousness of impact by cutting down speed, independent of all types of signalling and inter locking systems and human failure.
The drawback of this system is that it could not detect the rail tracks separated by a distance of 10-15 feet because of limitations of accuracy of GPS in our country. The ACD does not take into account factors based on environment, also the system is limited when one train is not ACD-equipped.
Aamir Ahamed et. al. titled 'Train Collision Avoidance Using GPS and GSM Module'proposed a system which will identify the obstacles that lie in the railway track. This system combines with PIC16F877A microcontroller, ultrasonic sensor and GPS and GSM. The ultrasonic sensor which is interfaced with the microcontroller is used to detect the obstacle. GPS is used to locate the train after being stopped by detecting obstacles. The system components, including a motor driver that controls train speed and an LCD display for system status, work together to ensure safety. However, the project faces limitations in high humidity or bad weather, as ultrasonic waves are affected by air moisture, impacting detection accuracy.
Thus, there is a need to address the disadvantages associated with the systems used in prior art. Embodiments of the present invention address the foregoing and other needs.The present invention simulates a train collision avoidance system using a computing platform ensuring that a safe distance is maintained.
OBJECTS OF THE INVENTION
The object of the present invention is to create a realistic simulation of two trains either approaching each other in opposite directions or traveling in the same direction along a straight track.
Another object of the present invention is to incorporate a dynamic speed adjustment mechanism that responds to the proximity of the two trains.
Yet another object of the present invention is toprovide a clear visual representation of the train movements over time.
Yet another object of the present invention is to ensure that asafe distance is maintained at the end of the simulation.
Yet another object of the present invention is to validate that the simulation successfully demonstrates effective collision avoidance.

SUMMARY OF THE INVENTION
The present invention disclosesa method to implement a train collision avoidance system.
According to an embodiment of the present invention, a train collision avoidancesystem simulates a collision avoidance scenario using MATLAB, focusing on the behaviour of two trains traveling either in the same direction or in opposite directions. By dynamically adjusting train speeds based on their proximity and applying deceleration techniques when necessary, the simulation demonstrates how modern safety mechanisms can be implemented to ensure that trains maintain a safe distance from one another, effectively avoiding collisions. The simulation employs a time-step-based approach, where the position, speed, and distance between two trains are updated at each step. For the same- direction scenario, the leading train maintains a constant speed, while the following train adjusts its speed to avoid overtaking. For the opposite-direction scenario, both trains decelerate as they approach one another, ensuring that they stop at a predefined safe distance. Key parameters such as initial speed, deceleration rate, stopping distance, and safe distance between trains are considered to create a realistic simulation. The visual representation of trains is provided using images that update in real-time, offering a clear view of their positions throughout the simulation. The results of the simulation show that the trains successfully maintain safe distances, and if necessary, decelerate to a complete stop, thereby preventing collisions. The invention highlights the importance of implementing automated train control systems in real-world railway networks to enhance safety and operational efficiency.
According to another embodiment of the present invention, a time step (dt) of 0.1 seconds is chosen for the simulation to balance computational efficiency and accuracy. The total duration of the simulation is set to 50 seconds, allowing sufficient time to observe the interactions between the trains.
According to another embodiment of the present invention, the initial speeds are defined as 40 m/s for Train 1 and 15 m/s for Train 2 (or 35 m/s and 25 m/s, respectively, in opposite direction scenarios). Initial positions are set to 0 meters for Train 1 and 1000 meters for Train 2 to simulate their movement towards each other.
According to another embodiment of the present invention, the safe distance is defined as 50-120 meters, and the stopping distance is set to 100-150 meters.
According to another embodiment of the present invention, the final distance maintained between Train 1 and Train 2 is equal to or greater than the predetermined safe distance, ensuring compliance with safety regulations.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1(a)showstrain collision avoidance simulation in same direction.
Figure 1(b) showstrain collision avoidance simulation in opposite direction.
DETAILED DESCRIPTION OF THE INVENTION
The following description includes the preferred best mode of one embodiment of the present invention. Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings.Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can bemade in the present invention without departing from the scope or spirit of the invention.
The train collision avoidance system is a critical aspect of railway safety management, aimed at preventing accidents caused by train collisions. The present invention simulates a train collision avoidance system using MATLAB, demonstrating how two trains, either moving towards each other or in the same direction, can adjust their speeds and safely stop without colliding. The simulation uses real-time speed monitoring, dynamic deceleration rates, and predefined safe distances to ensure the trains decelerate and stop when approaching too closely.
By visually representing the motion and interaction of the trains, the invention highlights key aspects of collision avoidance, such as safe stopping distances, the effect of deceleration rates, and real-time decision-making based on proximity. This simulation not only showcases the principles behind automated train control systems but also provides a platform for understanding how modern rail networks can employ such systems to enhance safety and prevent collisions.
Steps involved in implementing the train collision avoidance system:
A) Simulating two trains moving towards each other or in the same direction
The primary goal of the invention is to create a realistic simulation of two trains either approaching each other head-on (in opposite directions) or traveling in the same direction along a straight track. This setup allows for the examination of collision risks inherent in both scenarios. By modelling these situations, the invention aims to highlight the dynamics of train interactions, emphasizing how relative speed and distance play critical roles in preventing collisions.
B) Implementing speed deceleration and stopping mechanisms based on the distance between the trains
It is a crucial objective to incorporate a dynamic speed adjustment mechanism that responds to the proximity of the two trains. This involves:
1) Deceleration logic: Developing a mathematical model to determine when a train should begin to decelerate based on its current distance from the other train. This model will use parameters such as initial speed, safe distance, and stopping distance.
2) Stopping mechanism: Establishing a criteria when each train must stop to avoid a collision. This includes calculating the stopping distance required based on the train's speed and deceleration rate, ensuring that trains can halt safely within the designated stopping area.
3) This step ensures that trains can autonomously reduce their speed in a timely manner, preventing accidents through predictive adjustments.
C) Displayingtrain positions dynamically throughout the simulation
The simulation aims to provide a clear visual representation of the train movements over time. This includes:
1) Real-time visualization: Using MATLAB's graphical capabilities to continuously update the position of each train on a plot, allowing for a visual understanding of their relative speeds and distances throughout the simulation.
2) User-friendly interface: Ensuring that the train images are properly displayed and that any changes in position are immediately reflected on the visual interface. This enhances the user experience and aids in the comprehension of the simulation's dynamics.
3) By showcasing the trains' movements, users can observe how effective the deceleration and stopping mechanisms are in preventing collisions.
D) Ensuring the safe distance is maintained at the end of the simulation
An essential aspect of the invention is to verify that, at the conclusion of the simulation, the two trains maintain a safe distance between them, thereby confirming the success of the collision avoidance mechanisms. This involves:
1) Final position assessment: After the simulation runs its course, a final check will be conducted to ensure that the distance between the two trains meets or exceeds the predefined safe distance.
2) Data analysis: Collecting data on the final positions of both trains and analyzing it to evaluate the effectiveness of the implemented strategies. This analysis will provide insights into whether the objectives were met and if further improvements can be made.
This step emphasizes the importance of safety in train operations and aims to validate that the simulation successfully demonstrates effective collision avoidance.
Methodology
Software and tools
The primary software used in this invention is MATLAB, a powerful platform for numerical computation and visualization. Its robust features enable effective simulation of dynamic systems. MATLAB's image processing capabilities allow for the incorporation of graphical representations of trains. Train images are loaded using the imread function, facilitating the display of visuals that represent each train during the simulation. The use of MATLAB's plotting functions, such as plot and image, allows for dynamic updates of train positions on a defined axis, providing a clear visual output of the simulation's progress.
Simulation Setup
1) Time step and duration: A time step (dt) of 0.1 seconds is chosen for the simulation to balance computational efficiency and accuracy. The total duration of the simulation is set to 50 seconds, allowing sufficient time to observe the interactions between the trains.
2) Initial speeds and positions: The initial speeds are defined as 40 m/s for Train 1 and 15 m/s for Train 2 (or 35 m/s and 25 m/s, respectively, in opposite direction scenarios). Initial positions are set to 0 meters for Train 1 and 1000 meters for Train 2 to simulate their movement towards each other.
3) Distance parameters: Safe distance and stopping distance parameters are set to ensure trains maintain a safe operating distance. The safe distance is defined as 50-120 meters, and the stopping distance is set to 100-150 meters. These values dictate when the trains should start decelerating to avoid collisions.
Train movement logic
1) Deceleration and stopping conditions:
The simulation incorporates a logic that adjusts the speeds of the trains based on their relative distance. When the distance between the trains falls below a threshold (stopping distance + safe distance), the following logic applies:
• Speed reduction: If the distance is within the stopping distance, the speed of each train is reduced based on a predetermined deceleration rate (2 m/s²). This reduction continues until either the trains come to a stop or the distance exceeds the safe distance.
2) Safe stopping distance:
The trains are programmed to come to a complete stop when they reach the designated safe distance. If the distance is less than or equal to this safe distance, the speeds are set to zero, ensuring that both trains halt without passing each other.
Deceleration Formula
1) Speed adjustment logic:
The speed of each train is adjusted using a formula that takes into account the distance between the two trains. This formula operates as follows:
• When the distance between the trains is less than or equal to the stopping distance, the speed reduction is proportional to how close they are to each other. The closer the trains are (within the stopping distance), the greater the rate of deceleration.
The formula can be summarized as:
new_speed=max(0,current_speed−deceleration_rate×dt)
This approach ensures that the trains react appropriately to their proximity, enhancing the safety features of the simulation.
Visualization
1) Dynamic visualization process:
The simulation features real-time visualization of train movements on the track. The process includes:
• Image placement: Each train's image is initially placed on the plot using defined XData and YData values, representing their positions.
• Dynamic updates: Within each iteration of the simulation loop, the XData for each train image is updated based on the current positions of the trains. The set function is utilized to modify the positions of the train images dynamically.
• Pause for visualization: A pause function (pause(dt)) is incorporated to allow users to observe the movements of the trains in real time, ensuring the updates are visually coherent and easy to follow.
• Final position display: At the end of the simulation, the final positions of the trains are displayed in the command window, providing clear feedback on the outcome of the collision avoidance strategy.
Algorithm
Same direction
• Trains are initialized with specified speeds and starting positions.
• The simulation calculates the distance between the trains at each time step.
• Train 1's speed is adjusted to avoid collisions when the distance between the trains falls within a critical range.
• Speed reduction and eventual stopping of Train1 is implemented to maintain a safe distance from Train 2.
Opposite direction
• Both trains are initialized with defined speeds and initial positions.
• The simulation continuously monitors the distance between the trains.
• If the distance falls within a predefined safe range, Train 1's speed is reduced to prevent a collision.
• Both trains are stopped if the distance becomes critically close to ensure safety.
Results
Train speeds and distances
The simulation effectively demonstrates the dynamic behavior of two trains as they approach each other, showcasing how their speeds decrease over time in response to the distance between them. As the trains close in on each other, the following observations were made:
1) Speed reduction: Both trains exhibit a gradual decrease in speed as they approach the designated stopping distance. The initial speeds are reduced in a controlled manner based on their proximity to one another, ensuring a smooth deceleration.
2) Proportional deceleration: The deceleration is implemented to be proportional to the distance remaining, allowing for a realistic simulation of braking behavior. This adjustment ensures that trains have sufficient time to stop without crossing into the safe distance zone.
Throughout the simulation, it was observed that:
• Train 1 started at an initial speed of 40 m/s and reduced its speed to a complete stop as it reached the safe distance.
• Train 2, initially traveling at 15 m/s, similarly decreased its speed as it neared Train 1.
Final stopping positions
At the end of the simulation, both trains successfully halted at designated safe distances apart, thereby preventing any potential collision.
As shown in Figure 1(a)and Figure 1(b)the final distance maintained between Train 1 and Train 2 is equal to or greater than the predetermined safe distance, ensuring compliance with safety regulations.
This outcome demonstrates the effectiveness of the collision avoidance system, emphasizing its ability to prevent accidents in real-world scenarios where trains operate on shared tracks. 
, Claims:I/WE CLAIM
1. A method for implementing a train collision avoidance systemcomprises the steps of;
a) creating a realistic simulation of two trains either approaching each other or traveling in the same direction;
b) incorporatinga dynamic speed adjustment mechanism involving speed deceleration and stopping mechanismthat responds to the proximity of the two trains, wherein the parameters, initial speed, safe distance, and stopping distance are used;
c) displaying train positions dynamically throughout the simulation by using a computing platform; and
d) ensuring that a safe distance is maintained at the end of the simulation.
2. The methodas claimed in claim 1, wherein MATLAB is used for numerical computation and visualization.
3. The method as claimed in claim 1, whereintime step (dt) of 0.1 seconds is chosen for the simulation to balance computational efficiency and accuracy.
4. The method as claimed in claim 1, wherein the total duration of the simulation is set to 50 seconds.
5. The method as claimed in claim 1, wherein the safe distance is defined as 50-120 meters, while the stopping distance is defined as 100-150 meters.
6. The method as claimed in claim 1, wherein the trains can autonomously reduce their speed in a timely manner, preventing accidents through predictive adjustments.

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