Sliding mode based integrated guidance and autopilot for chasing UAV with the concept of time-scaled dynamic inversion

Integrated guidance and control approaches exploit the synergy between the guidance and the control of a vehicle. This study focuses on the integrated guidance and control(autopilot) design for a chasing UAV against a target aircraft. A second-order sliding structure for desired coupled roll and pull-up motions is proposed as a means to develop an integrated guidance and autopilot scheme. For easier design synthesis, intermediate control variables for partial derivatives of a sliding surface are carefully selected. As a consequence, the sliding surface structure is simple and sufficient to relate the actuator input to the sliding surface. The potential of the proposed method is demonstrated through an aircraft application by comparison of its simulation performance, and the number of tuning parameters with a synthesis technique where the guidance law and the controller are designed independently.