A PSL Ontology-based Shop Floor Dynamical Scheduler Design

Due to the complex, uncertainty and dynamics in the modern manufacturing environment, a flexible and robust shop floor scheduler is essential to achieve the production goals. A design framework of a shop floor dynamical scheduler is presented in this paper. The workflow and function modules of the scheduler are discussed in detail. A multi-step adaptive scheduling strategy and a process specification language, which is an ontology-based representation of process plan, are utilized in the proposed scheduler. The scheduler acquires the dispatching rule from the knowledge base and uses the buildin on-line simulator to evaluate the obtained rule. These technologies enable the scheduler to improve its fine-tune ability and effectively transfer process information into other heterogeneous information systems in a shop floor. The effectiveness of the suggested structure will be demonstrated via its application in the scheduling system of a manufacturing enterprise.     

基于系统综合效率最优的双轴并联PHEV联合优化控制策略

针对双轴并联插电式混合动力汽车控制策略与参数优化问题,综合考虑发动机和电动机工作区间对整车经济性的影响,以系统综合效率最高为目标提出了同时优化转矩分配和变速器挡位的联合优化控制策略,同时引入成本函数对整车经济性和换挡成本进行综合评价.制定控制策略后,以整车在NEDC工况下的电平衡油耗最低为优化目标,采用Isight/Cruise/Simulink联合仿真优化平台采用自适应模拟退火算法对联合优化控制策略参数进行了优化.仿真结果表明,经优化参数后的联合优化控制策略比未经参数优化的规则策略节省油耗7.7%,比运用初始规则策略节省油耗17.3%.     

基于新型趋近律的智能无人车辆线控转向系统滑模控制

路径跟踪是智能无人车辆的关键技术之一，其中，对线控转向系统的精确控制是影响智能无人车辆路径跟踪精度的重要因素.为提升线控转向系统在未知扰动下的转角动态响应性能和路径跟踪精度，本文基于一种新型趋近律设计了改进滑模控制方法并应用于线控转向系统.首先，考虑模型不确定、系统摩擦和齿条力建立线控转向系统数学模型.然后，分析得到滑模趋近律的设计原理，通过设计参数调节函数构建了一种新型滑模趋近律实现趋近速度的动态调节，并对比分析了其在离散形式下的性能.最后，针对线控转向系统，设计改进滑模控制方法.仿真和试验结果表明，改进滑模控制方法能够改善线控转向系统对转角的动态响应性能，提高路径跟踪精度.