Automated modular fixture planning based onlinkage mechanism theory1. IntroductionModular fixture is a kind of very promising flexible fixture devices in manufacturing. It is also used in assembly and verification processes. The use of modular fixture seems to be a trend in the manufacturing field as it can meet the desire for greater flexibility (i.e. it is able to deal with the workpieces with irregular shapes by combining modular fixture elements). By using modular fixtures, the flexibility and rapid response capability of manufacturing systems can be improved.However, modular fixture planning is a very difficult problem, especially for the modular fixture with the dowel-pin system as the locators of such modular fixtures can only be inserted into the fixed doweled holes. That is why modular fixture planning is still performed by fixture designers in industries up to now, relying on designer´s experiences and trial and error method. The main problem with manual planning of modular fixtures lies in that it is almost impossible for a designer to enumerate all the alternative fixture plans, which makes it extremely hard to find out the optimal fixture plan. Obviously it hinders the use of modular fixtures with dowel-pin system in industries. One way to solve the above problems is to use computer to assist designers in performing modular fixture planning. In recent years, the research on automated modular fixture planning has been paid more and more attention, and several approaches have been proposed in this area. Asada and By [1] described the basic concept of an adaptable fixturing system and its hardware implementation. The analytic tool of the fixture was developed, including that of accessibil...
