Variable stiffness characteristics of tapered curved beam
Anirudh R. KATGERI, R. CHIRAG, Ankith KACHINTHAYA, S. ASHISH, C.V. CHANDRASHEKARA
Abstract. Variable Stiffness Actuators (VSA) are modern mechanical systems, designed to exhibit varying stiffness/compliance characteristics in response to the external forces. It is an essential sub-system in the fields of robotics, biomechanics and prosthetics. Key elements of VSAs are springs, cables, pneumatic units, variable transmission mechanisms etc., playing a crucial role in providing a reliable and effective performance. A Miniature type straight and curved leaf-springs are more commonly used elements. The development and demonstration of varying stiffness characteristic of non-tapered curved beam in the form of S-springs, as a part of actuators has attained major recognition in the recent days. Present work is on demonstrating the varying stiffness characteristics of a tapered-curved beam, demonstrating modified varying stiffness range. A generalized and simplified mathematical model to estimate the deflection and corresponding stiffness of the tapered-curved beam for varying orientation is developed using Castigliano’s theorem. A limited parametric study for a tapered-curved beam is conducted and the results are presented along with the non-tapered curved beam. The initial results for non-tapered curved beam published in the literatures are compared with the present approach. Analytical results are validated with the results obtained by numerical approach. Numerical analysis is conducted on Ansys platform. It can be extended for a cost-effective design in robotics actuator’s design. The results are plotted in graphs to compare the deflection of tapered beams of different geometries for easy understanding of varying deflection and stiffness. Tapered curved beam can be incorporated in actuation mechanism such as gripping, pick and place or other robotic applications, requiring specific stiffness that can be altered through rotating the curved beam.
Keywords
Curved Beam, Variable Stiffness, Actuators
Published online 3/1/2025, 9 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Anirudh R. KATGERI, R. CHIRAG, Ankith KACHINTHAYA, S. ASHISH, C.V. CHANDRASHEKARA, Variable stiffness characteristics of tapered curved beam, Materials Research Proceedings, Vol. 49, pp 406-414, 2025
DOI: https://doi.org/10.21741/9781644903438-41
The article was published as article 41 of the book Mechanical Engineering for Sustainable Development
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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