Exploiting Null Space in Aerial Manipulation through Model-In-The-Loop Motion Planning

TL;DR

This paper introduces a novel motion planning method for aerial manipulators that integrates UAV dynamics and null space exploitation to improve end-effector trajectory tracking, validated through experiments.

Contribution

The proposed approach combines model-in-the-loop simulation with null space correction and applies TOPP-RA to enhance aerial manipulation accuracy.

Findings

Effective trajectory correction using null space exploitation.

Successful experimental validation of the planning framework.

Improved end-effector pose accuracy in aerial manipulation tasks.

Abstract

This paper presents a method for aerial manipulator end-effector trajectory tracking by encompassing dynamics of the Unmanned Aerial Vehicle (UAV) and null space of the manipulator attached to it in the motion planning procedure. The proposed method runs in phases. Trajectory planning starts by not accounting for roll and pitch angles of the underactuated UAV system. Next, we propose simulating the dynamics on such a trajectory and obtaining UAV attitude through the model. The full aerial manipulator state obtained in such a manner is further utilized to account for discrepancies in planned and simulated end-effector states. Finally, the end-effector pose is corrected through the null space of the manipulator to match the desired end-effector pose obtained in trajectory planning. Furthermore, we have applied the TOPP-RA approach on the UAV by invoking the differential flatness principle. Finally, we conducted experimental tests to verify effectiveness of the planning framework.