Kinematic Model Predictive Control for a Novel Tethered Aerial Cable-Driven Continuum Robot

Abstract

This paper presents the concept of a tethered aerial cable-driven continuum robot capable of flight and actuation whilst drawing its power from a ground station. The inspiration of this concept is to combine the manoeuvrability of an aerial vehicle with the flexibility of a continuum robot to make it an ideal candidate for a variety of operations in distant and narrow locations. We present a model predictive control (MPC) scheme to control the continuum robot’s position using only its velocity kinematics, thus removing the need for a computationally expensive dynamic model. To derive the velocity kinematics, we used the constant curvature assumption of a flexible rod and took its Jacobian matrix to get the required state-space model. The configuration states are estimated using optimisation-based inverse kinematics. We also present a prototype of the proposed system which to the knowledge of the authors, is the first to employ a tethered aerial cable-driven continuum robot capable of flight and transmission of mechanical work over 4 metres. We demonstrate the performance of the kinematic MPC through a series of experiments in both simulation and real life, and also show why a conventional PID controller falls short comparatively.