Investigation and Proposing a Method for Railroad Car Detachment
BACKGROUND
In the summer of 2021, I had the opportunity to work with Raja Company to solve one of the most catastrophic rail accidents for my undergraduate project. My project was based on IOT and designing whole system.
PROBLEM
The issue of rupture and escape of train wagons (separation of a number of wagons) has been one of the most accident-prone issues in the railway industry. The use of the end lights of the train and the counting of the axles mentioned that the use of the above-mentioned methods has a low safety factor, which has led to accidents.
PREVIOUS WORK
It can be said that some work has been done in this field but it is not practical or it has a high cost of implementation.
The actions and implementations done in the past can be divided into three groups:
One of the solutions that was considered is the microwave antenna that works in direct vision, the drawback of this method is that this type of antenna works in direct vision, which causes errors. In situations such as train movement in the tunnel, movement in the arc and the absence of the train in a straight line, this system gives a false warning of rupture.
Another method used was the wagon counting system, which in addition to the high cost it imposes, has many weaknesses, including theft of equipment and complexity of implementation. In fact, any system that is implemented outside the train car can be stolen.
Another solution that is currently used is to install a light at the end of the train, which the locomotive driver is obliged to confirm the existence of this light every 2 minutes in the mirror and make a note in their checklist. This method requires that the light always be in the view of the locomotive driver, which is not seen like a microwave antenna if the train is in an arc. Also, according to reports during the day, the presence of this lamp is not very useful because its light is not visible. Unfortunately, in some cases, there are reports that shows locomotives not being accurate, which, regardless of the rules and checking the lights in the mirror, try to register a report confirming that the lights have been seen.
SOLUTION
In this project, it is intended to introduce an intelligent (innovative) method based on wireless communication, a suitable solution with a high reliability to solve the problem of rupture. "Obviously, in the event of a rupture, the connection between the two antennas will be delayed and disrupted and then disconnected. Here we are going to measure the delay. If a significant increase in delay occurs, this We report the issue to the human factor as a rupture. The results of the research will be evaluated in several stages of the examination.
WORK FLOW
My goal is to implement a scalable and reliable alarm system that can alert you disconnection in an instant.
My intention is to get things done automatically to reduce human error. To achieving this goal, we defined the work flow steps.
Normal conditions and communication without problems of antennas
Wagons detached and antennas disconnected
When the train starts, the project starts automatically. Initially, it tries to establish a connection between the antennas. Then, after communicating, they start pinging each other, which causes them to calculate the delay. If the connection is lost, the locomotive driver will be alerted.
If driver receive a warning, it means that the wagons are separated from each other, and the train driver should investigate this issue and fix the problem. Since the timeout system may sometimes make a mistake, it tries to reconnect several times after failing to communicate, and if it fails, it will be warned.
WHY ZIGBEE
ZigBee is intended to be easier to use and less expensive than existing personal network technologies like Bluetooth. ZigBee is a wireless network technology that is both inexpensive and energy-efficient. It uses a mesh network topology, which allows for excellent reliability and an acceptable range.
ZigBee mesh topology: Every ZIGBEE network have one and only one coordinator
A comparison of different parameters for ZIGBEE, UWB, BLE and WI-FI
Comparison of the normalized energy consumption for each protocol
From the comparison of the above tables, it is easy to understand that ZigBee offers acceptable security along with the lowest energy consumption. Also, thanks to its star topology, this network has a high expansion capability that can provide a longer range while consuming less energy. We can also determine the frequency we want to be in that range with the least interference.
HARDWARE DESIGN
Hardware design is an important part because we need to be able to take advantage of ZigBee communication, especially in this project. There is a need for a decision-making and planned section to ensure communication and in the event of an interruption. Therefore, we have used the Arduino board according to the issue of energy consumption and implementation cost.
Measured power consumption of an Arduino UNO R3 board under different test conditions
Comparison of Arduino models for beginners
LCD display to Arduino connection
The Zigbee module also has a serial port that can be connected to the Arduino Ono through this port. For programming, it is appropriate to first use a three-hand shaking to ensure module connected successfully. After securing the temporary connection, we run an aging program on the Arduino, which I have implemented optimally. After ensuring a successful connection, we run a ping program on the Arduino, which I have implemented optimally.
