基于修正网重写系统的制造系统动态重构

Dynamic reconfiguration of manufacturing systems based on MNRS

智能制造模式要求制造系统能够快速动态重构以及时响应多品种、小批量产品的客户化、个性化定制的需求.本文从生产制造流程出发,针对不同输入输出函数下非托肯守恒复杂制造系统一般PN模型,在网重写系统的基础上提出修正网重写系统.修正网重写系统依据产品制造流程聚类对规则类库中重构单元子类进行系统的模块化封装,并制定相应的重构区域边界耦合约束与内部结构使能规则.构建的修正网重写系统重构单元类库具有行为特性继承的特点,保证局部区域重构后制造系统的活性、有界性及可逆性,根据制造系统修正网重写系统重写规则与重构步序可实现制造系统自主快速的动态重构.仿真结果与应用实例验证了修正网重写系统的可用性.

The manufacturing system under the smart manufacturing model is required to timely respond to the changing customization and individuation production demand of diversified small-lot products through quick dynamic reconfiguration. For the general Petri net with different input / output functions and non-conservative Tokens,a modified net rewriting system（ MNRS） is proposed according to the production process on the basis of NRS. Reconfiguration cells in the rule class library of MNRS are encapsulated systematically and modularly based on the manufacturing process of the products,and the corresponding boundary coupling and internal enabling rules of the reconfiguration area are formulated. The class library with reconfiguration cells in MNRS has the characteristic of behavioral property inheritance,which can guarantee the liveness,boundedness and reversibility of the manufacturing system after the local area reconfiguration,so that the autonomous,quick and dynamic reconfiguration of the manufacturing system can be achieved according to the rewriting rules and reconfiguration mechanism of MNRS. Simulation results and application cases verify the usability of MNRS.