On Computer Aided Conceptual Design Of Executive Mechanism Systems Based On FBS Model

It was reported that the conceptual design stage consumes only 5% of total cost of the product development, but determines almost 70% of the whole product development cost. Besides, the mistakes and errors made within this stage are impossible to be modified in the following stages. Furthermore, the conceptual design stage contributes more to the novelty of the products which helps to win the market competition.This thesis selected time serial interrelationship connecting executive mechanism systems as subject investigated. The research gives priority to theory, method, and application of the conceptual design based on function-behavior-structural design process model (FBS model). Five bottleneck problem of the conceptual design on the executive mechanism systems studied systematically and deeply. The main contributions are summarized as follows:1. Learning algorithm of the design expertise based on neural network This learning method once has accomplished learning using LVQ neural network, and then only knows code of mechanisms, designer that have not experience and knowledge can evaluate performance in the conceptual design stage like designer that have experience and knowledge.2. Computerized mapping from function to mechanical motions Motion forms of working stroke were defined through analyses of executive motion. All possible motions of working stroke on carrying out one function were evaluated on the basis of expertise. In order to seek optimum scheme among motion schemes of working stroke, which were required to fulfill whole technology movement process, evaluation criteria, mathematical models and solution procedure were established.3. Computer aided innovation of behavior structure for conceptual design of mechanical executive systemsThe behavior expression method is proposed. The computer reasoning procedure is described to support the innovation of behavior structure. The gene coding, genetic operation, mathematical model and genetic algorithm are detailed.4. Computer aided mapping from behavior to structure for conceptual design of mechanism systemBased on a systematic investigation of hundreds of existing mechanisms and machines, we identified movement (output) types of executive component in the actuating mechanisms. The correspondence relation table between action and existing mechanism was structured from point of view of the pure machine mechanics. Evaluate alternatives rule of the actuating mechanism system was established in order to select optimal alternative, further more, mathematical model selecting optimal alternative and solution procedure based on genetic algorithm were established.5. Optimization for evaluation and coordination of time and time relationshipTime and time relationship, that is, motion cycle diagram is a key in coordination design of executive mechanisms. Issue on former method of evaluation and coordination on time and time relationship were educed. In order to resolve the issue on former method of evaluation and coordination on time and time relationship, linear mini-max mathematical models were established.