Full Content is available to subscribers

Subscribe/Learn More  >

Experimental Validation of Compliant Joints in a Dynamic Spar Numerical Model

[+] Author Affiliations
Joseph Calogero, Mary Frecker

Pennsylvania State University, University Park, PA

Zohaib Hasnain, James E. Hubbard, Jr.

University of Maryland, Hampton, VA

Paper No. SMASIS2016-9074, pp. V002T06A006; 13 pages
  • ASME 2016 Conference on Smart Materials, Adaptive Structures and Intelligent Systems
  • Volume 2: Modeling, Simulation and Control; Bio-Inspired Smart Materials and Systems; Energy Harvesting
  • Stowe, Vermont, USA, September 28–30, 2016
  • Conference Sponsors: Aerospace Division
  • ISBN: 978-0-7918-5049-7
  • Copyright © 2016 by ASME


A dynamic spar numerical model for passive shape change is validated for a single degree of freedom contact-aided compliant mechanism (CCM) in a flapping spar. CCMs are modeled as compliant joints: spherical joints with distributed mass and three axis nonlinear torsional spring-dampers. Several assumptions were made in the original formulation of the model, such as assuming the spars were rigid and a simple damping model for the compliant joints. An experiment was performed to validate the assumptions and tune the model. Four configurations of the leading edge spar were tested: a solid spar, a previously designed CCM at two spatial locations, and a modified version of the CCM. Reflective markers were placed on each configuration, then the spars were inserted into the wing roots of a clamped ornithopter. An array of computer vision cameras was used to track the spar and CCM kinematics as they were flapped. First, a flapping angle function was extracted using a moving average of the flapping cycles. Then, a genetic algorithm was implemented to tune the stiffness and damping parameters for each of the configuration, minimizing the root mean square error between the model and experimental marker kinematics. The model was able to capture the deflection amplitude and harmonics of the CCMs with very good agreement and minimal to no phase shift.

Copyright © 2016 by ASME



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In