Design optimization of compact multi-degree-of-freedom mechatronic devices

Abstract

This research project mainly focuses on design optimization of compact, multi degree-of-freedom (CMDOF) mechatronic devices. In this work, CMDOF devices are defined as mechanical designs that are capable of executing multiple motions, whilst following strict weight and size limitations. These devices may range from a simple two-jaw gripper to a fully autonomous humanoid. Traditionally, design optimization entails the maximization (or minimization) of a very limited number of factors. In contrast, the design optimization technique being investigated in this work revolves around three conflicting yet desirable design attributes, being Simplicity, Dexterity and Usability. In this work, these three attributes have been expanded to incorporate a wide spectrum of design aspects. Detailed qualitative definitions of these terms are proposed. Moreover, a technique that quantifies these design attributes in an arbitrary device has been developed, termed the SDU tool. This technique provides an objective measure of the strengths and weaknesses of the design. A set of design guidelines that recommend means of achieving a sensible trade-off between the conflicting design attributes has been formulated. The outlined deliverables of this work are intended to assist designers and engineers in optimizing and comparing different designs of CMDOF devices. In this work, the design guidelines are applied to two case studies: (1) the development and construction of a robot hand, and (2) the conceptual design of a domestic device with a wide potential market. The former case study has served as a design improvement over a previously developed robot hand at the University of Malta. The latter case initially involved a market research of available domestic devices, whereby their common drawbacks were highlighted. A conceptual design of a new domestic device was developed, in attempt to overcome these shortcomings. In both case studies, designing efforts have been focussed on enhancing the effectiveness of the design, specifically focussing on the simplicity, dexterity and usability attributes.