Selection of Reference Points for Path Tracking Control Based on Rolling Prediction

Path tracking control techniques are commonly used in automated traveling systems for mobile equipment, where the role is to control the mobile equipment to travel along a reference path. The selection of reference points on the reference path is critical for path tracking control. However, current methods for selecting reference points face difficulties in simultaneously ensuring the accuracy and real-time performance required for path tracking control. To solve the problem, a method for selecting path tracking control reference points based on rolling prediction is proposed. The principle of this method is to predict the search range of the next control period by parameters such as the reference point of the current control period, the speed of the mobile equipment, the control period, and the mileage interval between adjacent points of the reference path. Subsequently, a localized optimization technique identifies the point on the reference path closest to the mobile equipment and is selected as the reference point. Our proposed rolling prediction method demonstrates commendable performance in ensuring path tracking control’s accuracy and real-time capabilities. In the simulation results, the absolute value of the displacement error in path tracking control does not exceed 0.1872 m. Compared with the equal-interval point selection method, the magnitude of reduction in the absolute value of displacement error can achieve at least 33.12%. Additionally, the average value of the time consumed in each control period by the rolling prediction method does not exceed 0.0709 ms and does not more than 2.87% of the average value of the total time consumed by the path tracking controller in each control period. In contrast, the existing global optimization method can occupy up to 82.36% of the total time.