Synthesis of a Force Generator using Two-Fold Tape Loops

Synthesis of a Force Generator using Two-Fold Tape Loops

de Jong, Martijn (TU Delft Mechanical, Maritime and Materials Engineering; TU Delft Precision and Microsystems Engineering)

van de Sande, Werner (graduation committee)
Herder, Just (mentor)

Delft University of Technology

ShellMech

2018-05-17

Normal linear springs have spring characteristics that are often too simplistic for complex applications. For instance in balancing applications, constant force or negative stiffness mechanisms are required. A tape loop, which consists of a two-fold tape spring, is a compliant shell mechanism which can act as a force generator with theoretically any force-displacement behavior by adjusting the tape spring’s cross-section.

In this thesis, a synthesis method is developed to determine the required tape spring geometry for obtaining the desired force-displacement behavior. Fifteen force-displacement curves are defined which all describe a unique characteristic behavior. These fifteen force-displacement curves are used as input to synthesize fifteen tape spring geometries. The resulting geometries are simulated in a finite element model to validate the synthesis method. The geometry with a non-zero constant force characteristic, is optimized, produced and tested in an experiment.

It is shown that a tape loop can generate all fifteen force-displacement curves by varying its cross-section and thereby can act as an all-purpose force generator. The production of tape loops however is challenging.

Force generators
Tape spring
Tape loops
Custom force displacement

http://resolver.tudelft.nl/uuid:4fc1b35f-f82f-43b5-8972-cbd51b0ec3d1

Student theses

master thesis

© 2018 Martijn de Jong