Hybrid Nonlinear Control of Quadcopter for Collision Avoidance Approach in Static Environment

A straightforward and effective nonlinear control strategy for quadcopters is presented, designed to prevent collisions using a Proportional–fractional order-integral–derivative sliding surface sliding mode control with backstepping controller. This controller enables the quadcopter to evade both single and multiple obstacles. When an obstacle with a high collision risk is identified, a virtual spherical boundary around the obstacle is created to define the collision zone. The controller then calculates the angular tracking errors between the quadcopter’s current trajectory and the tangential lines extending from its position to the boundary sphere, using these to adjust the quadcopter’s path for collision avoidance. A method is proposed to guide the quadcopter to its intended destination after successfully avoiding obstacles. The performance of this collision-avoidance algorithm is validated through simulation results.