Generation of Shape Instances for Ergonomic Optimization of Shapes

The Integrated Concept Advancement (ICA) research project aims for the development of a Computer Aided Conceptual Design engineering ontology for the shape of consumer products [1]. This paper focuses on the ergonomics boundary conditions (ICA-E). It considers an ergonomics shape optimization system (CAECD), see the accompanying paper for this conference [3]. FE analysis is used intensively to optimize the product shape for specific features of the pressure distribution and shape of the contact area. Sitting support was selected for testing and practical implementation of the methodology. The construction of a FE model needs a geometric model of the shape of the involved body parts, in casu the areas of the upper leg and the buttocks. The shape of the human body shows natural variability. The quantitative description of the shape for application in shape instancing, CAECD and FE modeling, is as yet in its infancy. In computer models of the human body the included anthropometric data are usually based on measurements of specific anatomical landmarks [4, 5], and the shape is usually indicated as elliptical cross sections or by straight lines connecting the landmarks [6, 7]. Such shape descriptions are unable to generate specific shape instances that are needed for FE modeling. This paper presents a method to generate (i) a vague model and (ii) geometric shape instances for specific body characteristics.