Control of Quadrotors for Tracking and Landing on a Mobile Platform

Abstract

Quadrotors have become very popular, both commercially and as research platforms. Numerous studies have been carried out on these aerial vehicles, covering different aspects of their dynamics and control. Many of the interesting applications of quadrotors arise when they are used as part of a cooperative robotic system, consisting of aerial and ground robots. Two essential steps toward realizing autonomous teams of aerial and ground robots are achieving position coordination between them, and autonomous landing of aerial robots on ground platforms. The goal of this paper is to tackle the problems of tracking and landing of an aerial robot on a mobile platform. Two approaches are presented for the control of a quadrotor with the purpose of tracking a mobile platform and landing on it while in motion. First, a sliding mode controller is proposed for the tracking application. The controller is then improved to an adaptive controller for the landing phase, taking into account an aerodynamic phenomenon known as the ground effect. Formal proof of stability is provided for both controllers using the Lyapunov stability theorem. Simulations are also conducted to assess the performance of the proposed control schemes, which demonstrate good tracking and landing behavior with realistic control action. The presented work was done as part of a bigger project aiming to develop a system consisting of two aerial and ground robots capable of coordinated tracking and landing.