Next Article in Journal
Multi-Objective Design Optimization of a Shape Memory Alloy Flexural Actuator
Previous Article in Journal
Stability and Performance Analysis of Electrodynamic Thrust Bearings
Article Menu

Export Article

Open AccessArticle

Design and Analysis of Novel Actuation Mechanism with Controllable Stiffness

Mechanical Engineering Department, Cleveland State University, 2121 Euclid Ave, Cleveland, OH 44115, USA
*
Author to whom correspondence should be addressed.
Actuators 2019, 8(1), 12; https://doi.org/10.3390/act8010012
Received: 3 December 2018 / Revised: 31 January 2019 / Accepted: 6 February 2019 / Published: 9 February 2019
  |  
PDF [1877 KB, uploaded 20 February 2019]
  |  

Abstract

Actuators intended for human–machine interaction systems are usually designed to be mechanically compliant. Conventional actuators are not suitable for this purpose due to typically high stiffness. Advanced powered prosthetic and orthotic devices can vary their stiffness during a motion cycle and are power-efficient. This paper proposes a novel actuator design that modulates stiffness by means of a flexible beam. A motorized drive system varies the active length of the cantilever beam, thus achieving stiffness modulation. New large deflection formulation for cantilever beams with rolling contact constraints is used to determine the moment produced by the actuator. To validate the proposed solution method, an experiment was performed to measure large static deformations of a cantilever beam with the same boundary conditions as in the actuator design. The experiments indicate excellent agreement between measured and calculated contact forces between beam and roller, from which the actuator moment is determined. View Full-Text
Keywords: variable-stiffness actuators; human-assist devices; flexible beams; energy-efficient actuators variable-stiffness actuators; human-assist devices; flexible beams; energy-efficient actuators
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

dos Santos, E.G.; Richter, H. Design and Analysis of Novel Actuation Mechanism with Controllable Stiffness. Actuators 2019, 8, 12.

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]
Actuators EISSN 2076-0825 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top