Structural Kinematics of In-Parallel-Actuated Robot-Arms

Abstract

An alternative is here put forward to counterbalance the present-day preoccupation with series-actuated robot-arms. A systematic study of robots and manipulators, now concentrating on “in-parallel” actuator-arrangements, reveals many geometries applicable either to entire robot-arms or to parts of otherwise series-actuated arms. No survey of this kind is possible without drawing heavily on the theory of screw systems. Having established a means of enumerating possible geometries, screw theory is again invoked to highlight, in broad terms, the patterns considered to be most promising. Criteria for avoiding undesirable robot-arm-configurations are touched upon, and certain aspects of the performance of in-parallel-actuated robot-arms are compared and contrasted with those of series-actuated arms. Within the bounds here set (thought to be realistic) the survey on its own is intended to be exhaustive, but many details remain to be investigated. This paper aims to do no more than edge open the door a little further towards in-parallel actuation in robot-arms; others may then consider that further study could be productive.

Direct Kinematics and Analytical Solution to 3RRR Parallel Planar Mechanisms

“…These mechanisms form one of the three categories of 3DOF planar parallel mechanisms as presented in [12]. Since the 3DOF planar parallel is made up of three chains connecting the base to the moving platform, each describing a circular locus with a quadratic equation, the resulting polynomial solution has a natural order of 2 3 = 8, admitting a maximum of 6 real solutions [13]. Minimal solutions were presented for specific cases of simplified 3DOF planar parallel mechanisms in [6] and more recently in [10] and [14].…”

Kinematic Analysis and Simulation of a Novel 2T1R Parallel Mechanism

“…Spatial parallel mechanism with two-translation and one-rotational (2T1R) DOFs, however, has been obtained less attentions in literatures. Hunt [3] proposed the 3-PRS PM in 1983. Refaat and Herve [4] have synthesized of several spatial mechanism; Zhang [5,6] presented structural synthesis of fully-isotropic 2T1R PM.…”

Delta robot controlled by robotic operating system

“…Many of these former studies were theoretical ones [7], until ABB Company introduced the IBR 360 Flexpicker model for practical or commercial use from the industry [8].…”