Workspace and Assembly modes in Fully-Parallel Manipulators : A Descriptive Study

TL;DR

This paper explores the distribution and role of assembly modes in fully-parallel manipulators' workspaces, analyzing singular and non-singular mode changes and their implications for trajectory planning.

Contribution

It provides a detailed analysis of assembly mode changes, especially non-singular ones, and their impact on trajectory planning in fully-parallel manipulators.

Findings

Non-singular assembly mode changes are crucial for trajectory planning.

Three cases are identified based on initial and final configurations relative to workspace domains.

Distribution of assembly modes affects feasible trajectory design.

Abstract

The goal of this paper is to explain, using a typical example, the distribution of the different assembly modes in the workspace and their effective role in the execution of trajectories. The singular and non-singular changes of assembly mode are described and compared to each other. The non-singular change of assembly mode is more deeply analysed and discussed in the context of trajectory planning. In particular, it is shown that, according to the location of the initial and final configurations with respect to the uniqueness domains in the workspace, there are three different cases to consider before planning a linking trajectory.