Sigmoid Function Optimization for Path Following Control with Obstacle Avoidance of an Autonomous Truck-trailer

In this study, an obstacle avoidance maneuver with sigmoid function optimization is applied on the path following control of the Autonomous truck-trailer. The accumulation of trailers and traffic density become obstacles in the lanes traversed by trailer trucks. A control design is needed that can perform obstacle avoidance actions in the form of optimal path changes. In the application of a path-following autonomous truck-trailer, the avoidance path reference must be dynamically adjusted to bring the system to a lane change. The optimization of the sigmoid function was proposed to obtain the optimal obstacle avoidance path reference based on the traction speed and steering angle. The MATLAB Fmincon Nonlinear Programming function is used to get the optimal solution which affects the concavity and distance of the turning path to the obstacle. The optimal turning path is integrated with the Lyapunov stability-based path follower control. This is intended to obtain a global asymptotic stable condition both under normal conditions and to avoid obstacles. Simulation is done by comparing the path pattern of the optimized and unoptimized sigmoid curves. The simulation results show the optimal turn path based on the mean of orientation angle and traction velocity in addition to the value of the performance index.