直线驱动铰链机构的键合图因果关系分类整理

采用键合图方法对直线驱动铰链机构进行动力学建模时,传统的虚拟弹性铰接点或拉格朗日乘子法会引入新的动态环节导致出现刚性问题,势流关系混乱难以规范化和模块化.提出了一种针对该机构的键合图因果关系分类整理方法,通过元件接口势流因果分析及元件间连接规则整理两个方面,分类为液压缸、主部件和连杆三种元件,并分别统一各铰接点势流因果关系接口为根点、外力顶点、力输出点和负载点,使得刚体元件接口的因果关系得以延续.在此基础上建立了元件间连接的规范方法以简化建模过程.最后反铲挖掘机的建模及仿真示例证明了本方法对于工程机械的常见工作机构均可适用.

Classification of Causality in Bond Graph Model for Linear Actuator Revolute Joint Mechanism

Bond graph modeling for linear actuator revolute joint mechanism which uses Lagrange approach or stiff compliance approach with new elements inserted causes stiff equation problems， and causality in bond graph is not classified and modularized. A causality classification method is proposed for modeling with this kind of mechanism. Classifications for elements are classified as main-body， cylinder and lever type by analysis of element bond graphs and connection patterns， and joints are classified as root， pusher， pushed and load type to maintain the original causal link. Causality determination principles are proposed by these definitions to make modeling orderliness. An excavator mechanism modeling and simulation demonstration proved that proposed method is suitable for mechanism cases of earthmoving vehicles.