Next Article in Journal
Lower Limb Exoskeleton for Rehabilitation with Improved Postural Equilibrium
Next Article in Special Issue
Optimal Kinematic Design of a 6-UCU Kind Gough-Stewart Platform with a Guaranteed Given Accuracy
Previous Article in Journal
VETO: An Immersive Virtual Environment for Tele-Operation
Previous Article in Special Issue
Motion Investigation of a Snake Robot with Different Scale Geometry and Coefficient of Friction
Article Menu

Export Article

Open AccessArticle
Robotics 2018, 7(2), 27; https://doi.org/10.3390/robotics7020027

Hexapods with Plane-Symmetric Self-Motions

Institute of Discrete Mathematics and Geometry, Vienna University of Technology, Wiedner Hauptstrasse 8-10/104, 1040 Vienna, Austria
Received: 30 April 2018 / Revised: 5 June 2018 / Accepted: 5 June 2018 / Published: 8 June 2018
(This article belongs to the Special Issue Kinematics and Robot Design)
View Full-Text   |   Download PDF [4742 KB, uploaded 8 June 2018]   |  

Abstract

A hexapod is a parallel manipulator where the platform is linked with the base by six legs, which are anchored via spherical joints. In general, such a mechanical device is rigid for fixed leg lengths, but, under particular conditions, it can perform a so-called self-motion. In this paper, we determine all hexapods possessing self-motions of a special type. The motions under consideration are so-called plane-symmetric ones, which are the straight forward spatial counterpart of planar/spherical symmetric rollings. The full classification of hexapods with plane-symmetric self-motions is achieved by formulating the problem in terms of algebraic geometry by means of Study parameters. It turns out that besides the planar/spherical symmetric rollings with circular paths and two trivial cases (butterfly self-motion and two-dimensional spherical self-motion), only one further solution exists, which is the so-called Duporcq hexapod. This manipulator, which is studied in detail in the last part of the paper, may be of interest for the design of deployable structures due to its kinematotropic behavior and total flat branching singularities. View Full-Text
Keywords: hexapod; self-motion; spatial symmetric rolling; plane-symmetric motion; Duporcq manipulator hexapod; self-motion; spatial symmetric rolling; plane-symmetric motion; Duporcq manipulator
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Nawratil, G. Hexapods with Plane-Symmetric Self-Motions. Robotics 2018, 7, 27.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Robotics EISSN 2218-6581 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top