ECS-9619363 Tao This proposal describes a university-industry collaborative research project to explore a new area of adaptive control: adaptive control of sandwich nonlinear systems, and to solve some long-standing and wide-range control problems of urgent relevance to theory as well as applications. The proposed research will focus on adaptive control of sandwich systems with linear and nonsmooth nonlinear dynamics and on adaptive control of two-layer systems with smooth and nonsmooth nonlinear dynamics. Typical nonsmooth nonlinear characteristics are dead-zone, backlash, hysteresis, other piecewise-linearities as well as frictions which are the main sources of component imperfections in control systems. The proposed adaptive inverse control approach employs an adaptive inverse to cancel the nonlinearity effects in order to achieve system performance improvements. This approach points to a new direction to design control systems using a new algorithm-based technology, which, after a period of learning or adaptation, can recognize component imperfections and compensate for their harmful effects. With such adaptive controllers, the component specifications could be greatly relaxed, their cost reduced, and their reliability increased. The results of this research will advance the knowledge of adaptive control significantly, provide new tools to effectively handle practical nonlinearities which have haunted the constructors of control systems for many years, and have many applications in defense and civil industries in which high-precision control systems are vital components. A-1
