Full-Pose Tracking Control for Aerial Robotic Systems with Laterally-Bounded Input Force

TL;DR

This paper introduces a geometric control strategy for a broad class of aerial robots with laterally bounded forces, enabling full-pose tracking under force constraints, with proven stability and demonstrated experimental effectiveness.

Contribution

A novel control method for Laterally Bounded Force aerial vehicles that achieves full-pose tracking with stability guarantees, accommodating both under- and fully-actuated platforms.

Findings

Proven exponential stability of full-pose tracking in SE(3).

Experimental validation shows improved performance over existing methods.

Controller handles unfeasible trajectories by ensuring positional tracking.

Abstract

In this paper, we define a general class of abstract aerial robotic systems named Laterally Bounded Force (LBF) vehicles, in which most of the control authority is expressed along a principal thrust direction, while in the lateral directions a (smaller and possibly null) force may be exploited to achieve full-pose tracking. This class approximates well platforms endowed with non-coplanar/non-collinear rotors that can use the tilted propellers to slightly change the orientation of the total thrust w.r.t. the body frame. For this broad class of systems, we introduce a new geometric control strategy in SE(3) to achieve, whenever made possible by the force constraints, the independent tracking of position-plus-orientation trajectories. The exponential tracking of a feasible full-pose reference trajectory is proven using a Lyapunov technique in SE(3). The method can deal seamlessly with both under- and fully-actuated LBF platforms. The controller guarantees the tracking of at least the positional part in the case that an unfeasible full-pose reference trajectory is provided. The paper provides several experimental tests clearly showing the practicability of the approach and the sharp improvement with respect to state of-the-art approaches.