Stabilization Control Using State Estimation for 4-DOF Hydraulic Excavator

In recent years, automation of construction machinery has gained increasing attention as a solution to the severe labor shortage in the construction industry. However, when sensor failures occur, the inability to accurately measure system states might significantly degrade control performance and increase the risk of accidents. To address this issue, this study proposes a control system design method for a 4-degree-of-freedom hydraulic excavator by combining Unscented Kalman Filter (UKF)-based state estimation with Lyapunov stabilization control. The proposed method estimates unmeasurable states using a UKF and ensures system stability via a control law derived from Lyapunov's direct method. Numerical simulations were conducted assuming a sensor fault in the boom’s angular velocity, and the results confirmed that the estimated states promptly converges to the real values and the system state is successfully stabilized to the target state. Thus, the effectiveness of the proposed method in this study is verified by numerical simulations.