A comprehensive static model of cable-driven multi-section continuum robots considering friction effect. (May 2019)

• Record Type: Journal Article
• Authors: Yuan, Han; Zhou, Lili; Xu, Wenfu
• Is Part Of: Mechanism and machine theory. Volume 135(2019)
• Page Start: 130
• Page End: 149
• Publication Date: 2019-05
• Subjects: Continuum robots -- Static modeling -- Friction effect -- Three dimensional motion -- Multi-section robots; Machine theory -- Periodicals; Machinery -- Periodicals; Machines -- Périodiques; Génie mécanique -- Périodiques; Machine theory; Machinery; Periodicals; 621.81
• DOI: 10.1016/j.mechmachtheory.2019.02.005
• Languages: English
• ISSNs: 0094-114X

Abstract

Highlights: A comprehensive 3D static model of multi-section continuum robots is proposed and experimentally validated. High modeling accuracy is proved by experiments. The average RMSE accounts for 1.82% of the robot length. Friction effect has non-negligible effect on the static robot profile, especially when the robot deflection is large. Friction-introduced history-dependency is found. The static robot shape is related to the driving-cable loading sequence. Abstract: Continuum robots featured by super dexterity and flexibility are excellent candidates for operations in confined environments. However, accurate modeling of continuum robots has been a challenge due to their large structural elasticity, attracting many research interests recently. This paper presents a comprehensive static model for continuum robots, considering most of the common forces and moments applied to the robot by both its own actuators and the external environments. Experimental results based on 68 tests show that the proposed model has high accuracy in describing the in-plane robot profile, but have certain errors for out-of-plane deformations. The average root-mean-square-error of the proposed model is 1.26 mm, which accounts for 1.82% of the total robot length. Moreover, the friction effect is investigated. Results show that actuating frictions could obviously change the robot deflection, and the static continuum robot shape is relevant to the historical cable tension status. Consequently, friction is vital to improve the static modeling accuracy of continuum robots.