Traffic Flow Evaluation for Platoons of Autonomous Vehicles using Constant Time-Gap Policy

Recently, the traffic flow for autonomous vehicles pla-toons has drawn the attention of researchers. For those vehicles, the utilization of different vehicles following policies needs investigation. Among those, the Constant Time-Gap (CTG) policy is commonly used in human-driven Adaptive Cruise Control (ACC)-equipped vehicles. In this work, the impact of the CTG policy on road traffic was investigated in addition to the string stability. A comparison between the Proportional-Integral-Derivative (PID) speed control and the CTG policy was illustrated. The range versus range-rate diagrams were implemented for evaluating the algorithms' string stability. For simplicity, the algorithms were applied to a platoon of mobile robots instead of real-size vehicles. In the model, a differential drive tri-cycle mobile robot was considered. Simulation results showed the advantage of the CTG policy regarding the string stability and the traffic flow. In addition, the CTG policy provided design parameters for controlling the traffic flow.