A Novel Robust Feedback Controller Design Methodology for Exploiting Directional Preferences

建议工作的主要目标是开发一种新的反馈设计方法，该方法利用多输入多输出系统中可能的方向性偏好。在过去的六十年里，反馈控制系统的设计积累了大量的知识。尽管已经发生了许多发展，但经典控制仍然在反馈控制设计中占据核心地位。建议的工作将利用古典设计提供的真正优势。SISO和MIMO设计的一个根本区别是在MIMO问题中存在方向性影响，而在SISO问题中没有这种影响。仔细检查现有的设计方法，如和QFT，很明显，具有方向性的现有灵活性没有得到利用。事实上，所有这些方法基本上都会在所有可能的方向上加强绩效。这样做的原因是设计或综合集中在闭环系统传递函数上。例如，即使当已知输出干扰在特定方向上时，也使灵敏度传递函数矩阵在所有可能的方向上都很小，尽管这不是必需的。提出了一种新的多输入多输出系统的方向反馈控制方法。这项研究将提供新的工具来解决许多先进控制问题，这些问题可能是现有方法无法解决的。例如，随着新的控制效应器和传感器的出现，预计非常高性能的系统将拥有高度冗余的执行器和传感器，这将使许多迄今未被考虑的性能要求得以结合。高性能飞机可能会包含高度冗余的控制执行器，可能没有垂直尾巴，可能能够在大姿态速率下进行非常高的g机动，并将在具有高度非线性空气动力学的扩展飞行包线上运行。可重构控制将变得越来越重要。可以预见，可重新配置的控制将允许设计和实施在损坏或系统故障的情况下执行系统性能的自动、在线优化的系统。提出目标的成功解决将通过提供一套新的设计工具，对机械和结构中的故障诊断和故障隔离、冗余管理和可重构控制系统设计产生立竿见影的效果。对复杂而昂贵的设备(如自动化制造系统、涡轮机械和传动系统)进行基于状态的监控，可以提高安全性和可靠性，并降低令人震惊的运维成本。目前，美国工业每年因维护不善而造成的成本估计为500亿美元。

The main objective of the proposed work is to develop a new feedback design methodology that takes advantage of directional preferences that are possible in multi-input multi-output systems. Over the last six decades a considerable body of knowledge has accumulated in the design of feedback control systems. In spite of the many developments that have occurred, classical control still occupies a central role in feedback control design. Proposed work will exploit the true advantages offered by classical design. One fundamental difference between SISO and MIMO designs is that there are directional influences in the MIMO problem whereas there is no such influence in the SISO problem. On closer examination of existing design methodologies such as and QFT it is clear that available flexibility with directional properties are not taken advantage of. As a matter of fact all these methodologies essentially enforce performance in all possible directions. The reason for this is that design or synthesis is focussed on a closed loop system transfer function. For example, even when an output disturbance is known to be in a specific direction the sensitivity transfer function matrix is made small in all possible directions although it is not necessary. We propose a new paradigm of directional feedback control of MIMO systems. This research would provide new tools to enable the solution of numerous advanced control problems that may not be solvable with existing methods. For example, with the advent of new control effectors and sensors it is anticipated that very high performance systems will possess highly redundant actuators and sensors that will enable the incorporation of many hitherto not considered performance requirements. High performance aircraft will likely incorporate highly redundant control actuators, may not have vertical tails, may be capable of very high g-maneuvers with large attitude rates and will operate over extended flight envelopes with highly nonlinear aerodynamics. Reconfigurable control will become ever so important. It can be envisioned that reconfigurable controls will allow design and implementation of systems that will perform automatic, on-line optimization of system performance in the event of damage or system failures. The successful resolution of proposed objectives will have an immediate effect on fault diagnosis and fault isolation in machinery and structures, redundancy management and reconfigurable control system design by making available a new set of design tools. Condition based monitoring of complex expensive equipment such as automated manufacturing systems, turbomachinery, and drive trains can improve safety and reliability as well as reduce the staggering O&M costs. The annual cost of poor maintenance to US industries is currently estimated at $50 billion.