A Portable Cable-Suspended Parallel Robot and Its Applications in Indoor Inspection

Cable-driven parallel robots (CDPRs) are now widely used in tasks such as filming and inspection due to their large workspace. Compared to unmanned aerial vehicles (UAVs), there's no need to navigate or position indoors for CDPRs, and CDPRs have lower noise levels and longer endurance. Therefore, this letter proposes a portable cable-suspended parallel robot (CSPR) to perform inspection tasks more effectively than UAVs in some indoor workplaces. It is highly integrated, compact, and lightweight, facilitating carrying, transportation and deployment. Then, the kinetostatic model of the proposed CSPR is established to analyze the advantages of the adopted cable configuration. To suppress the oscillation of the proposed under-actuated CSPR, reaction wheels are applied for active stabilization. Disturbance and trajectory experiments are carried out to validate the effectiveness of this oscillation suppression method. Moreover, with reaction wheels, the precision of the end-effector trajectory tracking improves by approximately 60%. At last, a demonstration experiment is conducted to show the application in tracking and filming a swimmer. The proposed CSPR could also be useful for other indoor applications, such as the volume measurement of indoor coal piles.