Abstract: Based on the parameterized coding of product shape, the method that lets customers participate the process is used to evaluate parameters’ weights. According to the order of the parameters’ weights, the shape coding of product design is sorted. The data is processed by the ways that degrade the ladders, and the seeking optimal is searched through interactive genetic algorithm. Then the product shape detail is determined gradually. The solving process is thoroughly based on decoded product shapes, which provides designers the visualized interface.

Key words: computer application, ladder-type method, degrade solution space, products&rsquo, shape design