Constraint modelling in 'design for all'

‘Design for All’, or Inclusive Design, is an approach to the design of products and workplaces that aims to maximise suitability for a wide range of consumers/workers. In particular attempts are made to include elderly and disabled consumers/workers without stigmatising the product or in any other way detracting from its attractiveness to younger more able-bodied users. The interest in Design for All stems from the increasing number of elderly and disabled people in western societies, the considerable economic power that they command and pressure from a wide variety of legislative forces. Research has recently been completed that provides a new basis for the application of ergonomics through computer aided design based on multivariate techniques using anthropometric and other data related to individuals rather than populations. The design tool created (known as HADRIAN) is briefly described. This tool is capable of assessing the percentage of the individuals that are able to perform a task whether this be in a domestic or industrial environment. However, it is not capable of suggesting design changes to improve this percentage accommodation, and hence ongoing research is concerned with ‘design synthesis’. The design synthesis approach uses a constraint modeller (SWORDS, which has been used elsewhere in many design and industrial applications) to search a potentially infinite design space to find sets of spatial characteristics of the design that maximise the user accommodation. This design synthesis approach is presented in this paper and described by a case study.