Download - Wireless Sensor-Based Traffic Light Control Malik Tubaishat, Qi Qi, Yi Shang, Hongchi Shi
Wireless Sensor-Based Traffic Light Control
Malik Tubaishat, Qi Qi, Yi Shang, Hongchi Shi
Problem Statement
• Comparison of performance of wireless sensor based networks(Single sensor and dual sensor) with fixed traffic cycle TLC.
• Non-Occupancy Detection(NOD) and Occupancy Detection(OD) based comparision
• Effect of sensor distance on Average waiting time.
Results
• Used GLD(Green Light District) for their simulation
• Implemented Fixed Light controller, Single Sensor based and Fixed Sensor based
• Some values:– Random Spawn Frequency : 0.1-0.35– Cycle length 5000 averaged over 5 cycles.
(a) urban-like map and (b) downtown-like map
One Sensor- Urban Network
One Sensor- Downtown Network
Key take-aways
• Two Sensor Model outperforms one Sensor Model
• Two sensor model performance is close to best first which knows the exact number of waiting vehicles.
• OD model, the closer the sensor to thejunction the better the performance is.
Sensor Placement in Real-Time Sensor Based Traffic Light Control
• Infrastructure Based Controllers• Performance based Measurements• Control Decision through Sensor data
Outline
• Agent based Controllers– Learn the expected waiting times of vehicles and
set the traffic lights accordingly
• Infrastructure Based Controllers– Change the traffic flow based on the current flow
of Traffic– They basically know the queue length and act on
this information
List of Controllers:• Random: Switched Traffic at Random• Most Cars: Move lanes regardless of the queue
length• Best First: Give priority to lanes with maximum
length• Longest Queue: Selects only the lane with
maximum length• Relative Longest Queue: No. off road users is
divided on the basis length of the lane to get relative rewards for traffic light settings
Control Decision Through Sensor Data
One Sensor Based Controller:
• NOD-Non-Occupancy Based Detection• OD-Occupancy Based Detection
• Two Sensor-based Controller
• The Gain Value is the queue length for infrastructure-based TLC.
• In every cycle the TLC adds the gain value for the possible sign configurations and selects the sign configuration with the maximum gain value
Future Work
• Focus work more towards increasing the life time of sensors
• Study performance in realtime with smaller intervals.
Reference• Wireless Sensor-Based Traffic Light Control, Malik Tubaishat, Qi Qi, Yi
Shang, Hongchi Shi, Consumer Communications and Networking Conference, 2008. CCNC 2008. 5th IEEE
Thank You
-Questions...