Hybrid Reasoning Groove, Department Of Modular Fixture Cad System

Fixtures are craft setups used to arrurately and stably locate the workpiece during machining process. Proper fixture design can improve the quality of parts and increase production efficience. Nowadays, the products that customers need are various, so it is very important to research a high performance computer aided modular fixture design system (CAMFDS). Though there have been some CAMFDs, most of them are unifunctional and their practicability is weak. In this paper, a computer aided fixture design system for slot-based modular fixture is developed using SolidWorks with Visual Basic, based on the integration of both rule-based reasoning and case-based reasoning. The major sdudy points are as follows:(1) Based on the analysis of various means used in CAMFDS and their weakness, a hybrid reasoning model combining RBR and CBR orienting to slot-based modular fixture is presented.(2) In order to obtain locating feature more accurately and efficiently, the definition of pseudo-locating feature is proposed, and an algorithm on excluding pseudo-locating feature is also described in this paper. The study shows that the index efficiency and accurance of real-locating feature are improved when the algorithm is used in CAMFDS.(3) A new approach that conbines the RBR and fuzzy comprehensive judgment method is proposed to accomplish the reasoning of locating and clamping feature. On the one hand, this approach can increase reasoning speed. On the other hand, the approach can introduce the experience of expert into CAMFDS, so as to make the reasoning results more desirable.(4) In order to express the feature of fixture example very well, a coding system with 53 parameters is proposed. Comparing with the past coding system, it includes the fixture information from locating and clamping reasoning module, which express the feature of fixture example more comprehensively. It is very helpful for us to retrieve the optimal fixture example. (5) An index strategy relying mainly on Nearest-Neighbor Approach with assistant of Knowledge Guided is proposed to express well the weighted coefficient of the feature of fixture case. It not only increases index efficiency and reliability, but also overcomes the shortcoming that a method using only Nearest-Neighbor approach or Knowledge Guided can not express the significance of case-feature attribute.(6) Based on the analysis of requirement from customers, a high performance CAD system for slot-based modular fixture is developed, based on Solidwork software platform and the several key algorithms presented in this paper. Two cases of fixture design show that the fixture feature coding sytem and the index strategy proposed in this paper are reasonable, and the CADS for slot-based modular fixture developed in this paper is also reliable.