Nonlinear Control for Autonomous Trajectory Tracking While Considering Collision Avoidance of UAVs Based on Geometric Relations

Abstract

Trajectory tracking with collision avoidance for a multicopter is solved based on geometrical relations. In this paper, a new method is proposed for a multicopter to move from the start position to a desired destination and track a pre-planned trajectory, while avoiding collisions with obstacles. The controller consists of two parts: First, a tracking control is introduced based on the errors between the relative position of the multicopter and the reference path. Second, once the obstacles with a high possibility of collision are detected, a boundary sphere/cylinder of the obstacle is generated by the dimensions of the vehicle and the obstacles, so as to define the safety and risk areas. Afterwards, from the relation between the vehicle’s motion direction, and the tangential lines from the vehicle’s current position to the sphere/cylinder of the obstacle, a collision detection angle is computed to decide the fastest direction to take in order to avoid a collision. The obstacle/collision avoidance control is activated locally when an object is close, and null if the vehicle moves away from the obstacles. The velocity control law and the guidance law are obtained from the Lyapunov stability. In addition, a proportional controller is used at the end of vehicle’s journey to ensure the vehicle stops at the target position. A numerical simulation in different scenarios was performed to prove the effectiveness of the proposed algorithm.

Unmanned Aerial Vehicles (UAVs): Collision Avoidance Systems and Approaches

“…Considering changes only in vertical directions, the authors use an integration equation of distance, track adjustment costs and time, under certain restrictions such as performance and distance constraints, to generate an optimal flight path to be navigated upon. An approach in which tracking control is integrated with a geometric collision avoidance method is proposed in [100]. Upon detection of obstacles, the obstacles with the highest risk are first selected.…”

“…In [102], the authors proposed a methodology of guiding the UAVs from mission start to destination whilst avoiding colliding with any obstacles in their path and keeping a track of the pre-defined trajectory. In order to achieve this optimally, the authors propose combining the collision avoidance control with the trajectory control of the system while solving these tasks independently and later combining them by a designed movement strategy.…”

Robust Dynamic Sliding Mode Control-Based PID–Super Twisting Algorithm and Disturbance Observer for Second-Order Nonlinear Systems: Application to UAVs

“…The dynamics model of a quadcopter is described in many existent approaches [44][45][46][47][48][49][50][51]. The essential frames include an Earth frame, E, and body frame, B, as shown in Figure 2.…”

Robust Geometric Navigation of a Quadrotor UAV on SE(3)

“…In ref. [17] authors presented a strategy for the trajectory tracking of a quadrotor with collision avoidance and based on geometrical relations. Numerical simulations are performed to prove the proposed algorithm.…”