ABSTRACT
Constraint based modell ing has been predominantly used at the University of Bath to redesign machinery for the packaging industry. This approach involves the manipUlation of geometric entities through the use of rules that arc written in the form of mathematical or geometric relationships . The rotation, translation and scaling of the geometric entities about their individual axes are considered as variables that can be invoked and resolved through the use of rules, as described by Medland et at ( 1 995).
