Design and Control of a Variable Aerial Cable Towed System

Abstract

Aerial Cable Towed Systems (ACTS) are composed of several Unmanned Aerial Vehicles (UAVs) connected to a payload by cables. Compared to towing objects from individual aerial vehicles, an ACTS has significant advantages such as heavier payload capacity, modularity, and full control of the payload pose. They are however generally large with limited ability to meet geometric constraints while avoiding collisions between UAVs. This paper presents the modelling, performance analysis, design, and a proposed controller for a novel ACTS with variable cable lengths, named Variable Aerial Cable Towed System (VACTS).Winches are embedded on the UAVs for actuating the cable lengths similar to a Cable-Driven Parallel Robot to increase the versatility of the ACTS. The general geometric, kinematic and dynamic models of the VACTS are derived, followed by the development of a centralized feedback linearization controller. The design is based on a wrench analysis of the VACTS, without constraining the cables to pass through the UAV center of mass, as in current works. Additionally, the performance of the VACTS and ACTS are compared showing that the added versatility comes at the cost of payload and configuration flexibility. A prototype confirms the feasibility of the system.

A modular computational framework for the dynamic analyses of cable-driven parallel robots with different types of actuation including the effects of inertia, elasticity and damping of cables

“… CDPR cable-driven parallel robot MP moving platform DoF degree(s)-of-freedom VACTS variable aerial cable towed system (see [1]) FD forward dynamics ID inverse dynamics EoM equation of motion SDE spring and damper element RSSLM recursive sub-system-level Lagrange multiplier approach (see [2]) MRFE modified rigid finite element (see, e.g., [3]) GIM generalised inertia matrix (see, e.g., [4]) DAE differential-algebraic equation - CDPR a CDPR with distinct exit and anchoring points of cables (see, e.g., [5], pp. - ) joint positions, velocities and accelerations, respectively GIM of the robot centripetal and Coriolis matrix (see Eq.…”

Shared Control of an Aerial Cooperative Transportation System with a Cable-suspended Payload

“…This wrench analysis is combined in [8] with a modified version of a controller developed for discretely reconfigurable CDPRs. The parallelism between ACTS and CDPR is even more pronounced in [30], where the MAVs of the transportation system are equipped with actuated winches.…”

Review of Aerial Manipulator and its Control

“…Nicotra et al [32] developed a nested saturation control method for quadrotors to transport suspension cable payloads. Li Zhen et al [33] proposed a variable aviation streamer system. The length of the driven cable can change the size of the entire system.…”