Design and Analysis of a Series-Parallel Hybrid 3-SPS-U Mechanism

Abstract

This article presents the design and analysis of a seriesparallel hybrid tensegrity mechanism. The mechanism has two stages which consist of a fixed base, an intermediate mobile platform, and a mobile end-effector. Each stage is connected by three tension springs and a universal joint in the center. By correlating to a 3-SPS-U architecture, the geometrical equations for the mechanism are generated in the Euler space and the Tilt & Torsion space. To simplify the computations, the Tilt & Torsion space is employed for the analysis of the mechanism. A stability analysis is carried out initially to identify the design parameters of the mechanism in the static mode through an optimization approach. By employing algebraic methods, the singularity analysis is then carried out on the hybrid mechanism. The results of this analysis helped in identifying the feasible workspace and the maximum tilt limits of the architecture. A mapping equation that demonstrates the relation between the Tilt & Torsion angles and the Euler angles is then presented using the results of singularity analysis. A numerical simulation is then demonstrated to validate the results of the analysis. The mechanism under study is then proposed to be integrated into a piping inspection robot for passing through elbows and T-sections.