Observer-based trajectory inclination control with weight-on-bit uncertainty in directional drilling systems

This study concerns trajectory inclination control with the uncertainty of weight-on-bit for the directional drilling process. The trajectory inclination model considers the variation of weight-on-bit and accounts for the uncertainty term of the model. A two-layer observer-based control scheme of the trajectory inclination is developed to compensate for the unavailability of direct measurement of trajectory inclination, the uncertainty of weight-on-bit, and external disturbances. The system's stability is analyzed through the Lyapunov function and then converted to a linear matrix inequality (LMI) form to obtain the control parameter gains. Eventually, some simulations manifest our control system can effectively eliminate the influence of uncertainty of weiaht-on-bit and external disturbances.