Fuzzy control over constraint satisfaction problem solving in structural design

The authors address the problems of usual constraint satisfaction (CSP) in structural design and present a technique to control the design by applying a new model called the fuzzy constraint satisfaction problem (FCSP). In FCSP both the constraints and the domains of variables are allowed to be fuzzy. It helps in reasoning about the degree to which a constraint is satisfied and to avoid the statical partition of the set of constraints into hard and soft as is traditionally used. With fuzzy control of the constraint satisfaction problem, the design can be optimized with the satisfaction index lambda which leads to meaningful results that the usual CSP cannot provide. To show the benefits of FCSP, an example of structural design is given.