A Robust Control Approach to AMSs by Using the Implementation of Strong and Weak Robustness
将具有不可靠资源的自动制造系统分为非鲁棒、弱鲁棒和强鲁棒三类，提出基于新Petri网模型和死锁避免算法的鲁棒控制方法，确保系统在资源故障下仍能完成所有产品。
In automated manufacturing systems, the completion of all essential products must be guaranteed. Hence, each process of a system should have outputs. This outcome requires assurance that a system composed of a set of processes with shared and dedicated resources will operate smoothly. Shared resources can introduce deadlock problems through circular waits. In most methods to investigate the deadlock issues, shared and dedicated resources are assumed to never fail. However, the failure of one resource may cause the real crash of an entire system such that no finished products can output. Systems with unreliable resources are classified in this article into three types: 1) nonrobust systems; 2) weakly robust systems; and 3) strongly robust systems. A robust control method based on this classification is necessary for a system. Two approaches to robust control are developed. First, systems of sequential systems with shared and copied resources <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$(S^{4} C R\text{s}$ </tex-math></inline-formula> ), which is a new type of petri nets, is designed to strengthen the robustness of systems. It ensures that processes with unreliable resources complete their products. In addition, based on a deadlock-avoidance algorithm, a robustness algorithm is proposed. This ensures a system can operate without disruption under any situations.