Design and control of a 6-DOF hybrid thrustered cable-suspended parallel robot using a fully-actuated hexarotor
Year: 2026
Type: article
Abstract: Cable-suspended parallel robots (CSPRs) are under-actuated robots in which the end-effector is suspended from above, thereby reducing interference with surrounding objects because no cables are arranged below it. However, in CSPRs, cable tension is mainly maintained by the gravity of the end-effector, which limits their wrench generation capability. Hybrid CSPRs with propeller-based thrusters have been proposed to address this issue, but online force coordination during continuous motion requires further investigation. This paper proposes a 6-DOF hybrid thrustered cable-suspended parallel robot (TCSPR), referred to as the 3C-FAH TCSPR, where three cables are attached to the center of mass of the end-effector, which serves as the reference point, for mainly translational actuation, while six thrusters are arranged in a fully-actuated hexarotor configuration to control orientation and assist cable-tension regulation. Owing to this arrangement, the end-effector position and orientation can be controlled independently. To realize online force distribution for this hybrid-actuation redundant system, the Improved Closed-Form Method (ICFM), originally developed for conventional over-constrained cable-driven parallel robots, is adapted to account for the different actuation characteristics of cables and thrusters. Based on the Adapted ICFM, which allocates cable tensions and auxiliary thruster forces, numerical workspace analysis shows that the computed feasible workspace is expanded compared with a conventional three-cable CSPR without hexarotor assistance. A prototype with integrated mechanical, electrical, and control systems is developed for experimental validation. Results of trajectory-tracking experiments using this prototype show reasonably stable tracking behavior within the tested range, demonstrating the basic feasibility of the 3C-FAH TCSPR.
Source: Advanced Robotics
Institutions: Institute of Science Tokyo, Ricoh (Japan)
Language: English
Subfield: Control and Systems Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Award: G6968929258
OpenAlex ID: W7219691841