Publication

Position and singularity analysis of a class of planar parallel manipulators with a reconfigurable end-effector

Journal Article (2021)

Journal

Machines

Pages

7

Volume

9

Number

1

Doc link

https://doi.org/10.3390/machines9010007

File

Download the digital copy of the doc pdf document

Abstract

Parallel robots with configurable platforms are a class of robots in which the end-effector has an inner mobility, so that its overall shape can be reconfigured: in most cases, the end-effector is thus a closed-loop kinematic chain composed of rigid links. These robots have a greater flexibility in their motion and control with respect to rigid-platform parallel architectures, but their kinematics is more challenging to analyze. In our work, we consider n-RRR planar configurable robots, in which the end-effector is a chain composed of n links and revolute joints, and is controlled by n rotary actuators located on the base of the mechanism. In particular, we study the geometrical design of such robots and their direct and inverse kinematics for n = 4, n = 5 and n = 6; we employ the bilateration method, which can simplify the kinematic analysis and allows us to generalize the approach and the results obtained for the 3-RRR mechanism to n-RRR robots (with n > 3). Then, we study the singularity configurations of these robot architectures. Finally, we present the results from experimental tests that have been performed on a 5–RRR robot prototype.

Categories

robots.

Author keywords

parallel manipulators; reconfigurability; direct kinematics; singularities

Scientific reference

T. Marchi, G. Mottola, J.M. Porta, F. Thomas and M. Carricato. Position and singularity analysis of a class of planar parallel manipulators with a reconfigurable end-effector. Machines, 9(1): 7, 2021.