Free-shape contour control for excavators based on cross-coupling and double error pre-compensation

In construction automation, excavators frequently undertake intricate contouring tasks, including precise leveling and surface shaping. However, the absence of a dynamic model and error estimation approach for curved contours in existing solutions can significantly reduce operational precision. To address these challenges, a free -shape contour control method based on cross -coupling and double error pre -compensation is presented. The double error is a linear combination of tracking error and contour error. The curve contour error is calculated using a parameter -based backward approximation method. Furthermore, nonlinear disturbance observer and sliding mode control are combined to deal with the lumped disturbance. Simulation and platform experiment results demonstrate that the proposed controller has smaller chattering and contour error under loaded and extreme operating conditions. The control method provides an effective solution for excavators to complete different types of contour tasks. For further study, hydraulic system modeling will be considered to improve the performance of control system.