Modal measurements and model corrections of a large stroke compliant mechanism

Journal Title: Archive of Mechanical Engineering - Year 2014, Vol 0, Issue 2

Abstract

In modelling flexure based mechanisms, generally flexures are modelled perfectly aligned and nominal values are assumed for the dimensions. To test the validity of these assumptions for a two Degrees Of Freedom (DOF) large stroke compliant mechanism, eigenfrequency and mode shape measurements are compared to results obtained with a flexible multibody model. The mechanism consists of eleven cross flexures and seven interconnecting bodies. From the measurements 30% lower eigenfrequencies are observed than those obtained with the model. With a simplified model, it is demonstrated that these differences can be attributed to wrongly assumed leaf spring thickness and misalignment of the leaf springs in the cross flexures. These manufacturing tolerances thus significantly affect the behaviour of the two DOF mechanism, even though it was designed using the exact constraint design principle. This design principle avoids overconstraints to limit internal stresses due to manufacturing tolerances, yet this paper shows clearly that manufacturing imperfections can still result in significantly different dynamic behaviour.

Authors and Affiliations

S. E. Boer, W. B. J. Hakvoort, R. G. K. M. Aarts, W. Wijma, D. M. Brouwer

Keywords

Related Articles

Structural and thermal analysis of automotive disc brake rotor

The main purpose of this study is to analyze the thermomechanical behavior of the dry contact between the brake disc and pads during the braking phase. The simulation strategy is based on softawe ANSYS11. The modeling of...

Stack parameters effect on the performance of anharmonic resonator thermoacoustic heat engine

A thermoacoustic heat engine (TAHE) converts heat into acoustic power with no moving parts. It exhibits several advantages over traditional engines, such as simple design, stable functionality, and environment-friendly w...

Rehabilitation robot prototypes developed by the ITAM Zabrze

Limb physical movements disability is the result of illnesses or serious injuries, impaired execution of daily activities and limitations or even inability to perform working activity. Restoration of fitness in such case...

Investigation of design features of compressor casing treatment

Casing treatment in the form of circumferential grooves over a rotor blade tips is used for improvement of an axial compressor performance. Usually, these grooves extend compressor’s stall range (stable operational range...

Effect of tool geometry and welding speed on mechanical properties and microstructure of friction stir welded joints of aluminium alloys AA6082-T6

Friction stir welding is a solid state innovative joining technique, widely being used for joining aluminium alloys in aerospace, marine automotive and many other applications of commercial importance. The welding parame...

Download PDF file
  • EP ID EP166726
  • DOI 10.2478/meceng-2014-0020
  • Views 92
  • Downloads 0

How To Cite

S. E. Boer, W. B. J. Hakvoort, R. G. K. M. Aarts, W. Wijma, D. M. Brouwer (2014). Modal measurements and model corrections of a large stroke compliant mechanism. Archive of Mechanical Engineering, 0(2), 347-366. https://europub.co.uk/articles/-A-166726