Local redesign for additive manufacturability of compliant mechanisms using topology optimization

Stijn Koppen, Emma Hoes, Matthijs Langelaar, Mary I. Frecker

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

Compliant mechanisms are crucial components in current and future high-precision applications. Topology optimization and additive manufacturing offer freedom to design complex compliant mechanisms that were impossible to realize using conventional manufacturing. Design for additive manufacturing constraints, such as the maximum overhang angle and minimum feature size, tend to drastically decrease the performance of topology optimized compliant mechanisms. It is observed that, among others, design for additive manufacturing constraints are only dominant in the flexure regions. Flexures are most sensitive to manufacturing errors, experience the highest stress levels and removal of support material carries the highest risk of failure. It is crucial to impose these constraints on the flexure regions, while in others part of the compliant mechanism design, these constraints can be relaxed. We propose to first design the global compliant mechanism layout in the full domain without imposing any design for additive manufacturing constraints. Subsequently we redesign selected refined local redesign domains with design for additive manufacturing constraints, whilst simultaneously considering the mechanism performance. The method is applied to a single-input-multi-output compliant mechanism case study, limiting the maximum overhang angle, introducing manufacturing robustness and limiting the maximum stress levels of a selected refined redesign domain. The high resolution local redesigns are detailed and accurate, without a large additional computational effort or decrease in mechanism performance. Thereto, the method proves widely applicable, computationally efficient and effective in its purpose.

Original languageEnglish (US)
Title of host publication45th Mechanisms and Robotics Conference (MR)
PublisherAmerican Society of Mechanical Engineers (ASME)
ISBN (Electronic)9780791885444
DOIs
StatePublished - 2021
Event45th Mechanisms and Robotics Conference, MR 2021, Held as Part of the ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC-CIE 2021 - Virtual, Online
Duration: Aug 17 2021Aug 19 2021

Publication series

NameProceedings of the ASME Design Engineering Technical Conference
Volume8A-2021

Conference

Conference45th Mechanisms and Robotics Conference, MR 2021, Held as Part of the ASME 2021 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC-CIE 2021
CityVirtual, Online
Period8/17/218/19/21

All Science Journal Classification (ASJC) codes

  • Mechanical Engineering
  • Computer Graphics and Computer-Aided Design
  • Computer Science Applications
  • Modeling and Simulation

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