Emergency vehicle priority and traffic light control at intersection using IoT

Project Title

Emergency vehicle priority and traffic light control at intersection using IoT

Project Area of Specialization Information & Communication TechnologyProject Summary

Traditional traffic control sytems have fixed sequence for each approach of the intersection and fixed duration of green light signal for each approach which results in the waste of time, fuel consumption, increase in number of accidents at intersections, heavy loss of lives due to latency of emergency vehicles. Therefore an intelligent intersection control system is required that prioritizes the transit of emergency vehicles and also reduces the waiting time of regular traffic.

Hence, the aim of this research is the development of intersection control system that prioritizes emergency vehicles and reduces routine traffic congestion at intersections by utilizing V2I communication. For this purpose, we will install NodeMCU ESP8266, GPS receiver module in non-emergency vehicles and GSM module along with controller and GPS receiver in emergency vehicles. A WiFi router installed at intersection will provide WiFi signals. Each vehicle approaching an intersection, will send a beacon message to the centralized controller at intersection. The centralized controller will then count the number of vehicles on each approach based on received beacon messages. Afterwards, the controller will turn on green signal for the approach having high vehicle density. Moreover, if an emergency vehicles approaches an intersection, the controller prioritizes the emergency vehicle by showing green light to the respective approach containing emergency vehicle.

Project Objectives

The project's main objectives are given as follows:
• Prioritize Emergency Vehicle at intersection to reduce their waiting time.
• To assign highest priority to the approach which has the highest vehicle density to avoid long queue of vehicles.
• To assign variable time to four approaches of intersection based on the number of vehicles to reduce waiting time for non-emergency vehicles.
• Maintain the dynamic traffc flow for busy intersections.

Project Implementation Method

Project implementation menthodology:

The system immediately reacts to emergency vehicles (EV) arriving at the intersection and handles the smooth flow of non-emergency vehicles as well. The system contains two main parts i.e., Vehicle on Board Unit (OBU) and road side fixed Intersection Controller (IC). OBU is installed on every vehicle which is responsible for transmitting vehicle’s position and direction information and receiving traffic light information from the AP. Each OBU transmits a beacon message every second that includes vehicle position, direction and velocity information. Similarly, OBU is installed in the emergency vehicles like fire brigades, ambulances, police vans, military vehicles etc to transmit their local information. On the other side, the IC is positioned at the intersection as shown in Figure ?1 and is responsible for collecting the location information of the vehicles and for constantly tracking the arrival of beacon message from the EV, so that the lane comprising EV must be assigned high priority for crossing intersection. IC also priorities the regular traffic flow by calculating the traffic density in each direction which is explained later.

Figure 1: Block diagram of proposed system

Emergency Vehicle Priority:

Emergency vehicle, upon approaching at intersection, will periodically transmit a beacon message. After receiving a beacon message from EV, IC checks that EPR field is set to 1 which indicates that beacon is sent by EV. Then, the IC transmits grant message containing green signal to the lane in which EV is present and red signal to remaining directions as shown in the flow chart of Figure 2. 

Figure 2: Flow chart of Emergency vehicle

Non-Emergency Vehicle Priority Scheme

In case of non-emergency vehicles, IC calculates the traffic density on each approach  and then calculates time for each approach by utilizing Eq. (1).

                          T =  (s / v ) * ( Nd / Nm)

Where, 

• S= Distance
• V= Velocity
• N(d)= Number of Vehicle per direction
• N(M)= Maximum Number of vehicle per direction

After calculating time for each approach, the IC assigns green signal to approach with high vehicular density as shown in Figure 3.

Figure 3: Flow chart of Intersection controller

Benefits of the Project

The project plays a vital role in the betterment of the traffic system of a country. Accidents and fatalities due to increase in number of vehicles has become a global challenge. This project helps to overcome the heavy life losses due to inadequacy of traditional trac control system. Moreover, the late arrival of emergency vehicles also causes casualties. So this project overcomes the problem by reducing the latency of emergency vehicle. Hence much needed by the society for the well being of the citizens.

Technical Details of Final Deliverable

The Final deliverable of the proposed system contains the following key elements:

• Intersection Controller: The Intersection controller (IC) manages the arrival of emergency and non-emergency vehicles. It prioritises emergency vehicles at intersections and assigns the highest priorities to high-density roads or approaches.
• On Board Unit: OBUs are deployed inside vehicles to transmit their position and direction information to the IC.
• Emergency vehicle Unit: An emergency vehicle approaching an intersection wirelessly communicates with the IC for priority assignment.

For this purpose, we will install NodeMCU
ESP8266, GPS receiver module in non-emergency vehicles as OBU. Similarly, GSM module along
with NOdeMCU ESP8266 and GPS receiver will be installed in emergency vehicles as emergency vehilce unit . The intersection controller  will contain NodeMCU ESP8266 and GSM module to interact with both emergency and non-emergency vehicles.

Final Deliverable of the Project Hardware SystemCore Industry TransportationOther Industries Telecommunication Core Technology Internet of Things (IoT)Other Technologies OthersSustainable Development Goals Sustainable Cities and CommunitiesRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	65300
NodeMCU ESP8266	Equipment	6	650	3900
NEO 6M GPS Module	Equipment	5	1100	5500
SIM800L GSM Module	Equipment	2	1450	2900
Traffic lights Boxes	Equipment	4	12000	48000
Miscellaneous equipment used for assembling	Miscellaneous	1	5000	5000