Virtual and Physical Prototyping of a Cable-Driven Compliant Robotic Wrist

Abstract

This article presents the virtual prototyping and experimental validation of a two degrees of freedom (DOFs) cable-actuated robotic wrist. The two DOFs have been achieved using two pairs of cross axis flexural pivot compliant transmission elements, supported by passive rolling contacts that guide deflection and prevent buckling phenomena. In this study, a simplified virtual prototype has been developed based on Finite Element Analysis data. Through appropriate simplifications aimed at replacing the soft components in the model with their rigid counterparts, together with a suitable cable model, a 99.98% reduction in computational time has been achieved. In addition, a friction estimation model based on Euler–Eytelwein’s formula has been implemented and integrated into the control algorithm used to fine-tune the system parameters and estimate its response speed. The development of a computationally efficient virtual prototype allows testing of the device’s control algorithm in various application scenarios, as well as optimization routines, even before the physical prototype is built, significantly reducing time and costs. Finally, experimental validation has been conducted, confirming the accuracy of the model for both individual modules and the complete device. This comprehensive validation highlights the reliability of the simplified virtual prototype in representing real-world behavior, underscoring its potential for optimizing future designs and control strategies in cable-actuated robotic systems.