This study improves the performance of a previously developed acoustic actuator in the presence of an acoustic duct system with strong pressure coupling. The speaker dynamics and the acoustic duct dynamics are first modeled separately. The two systems are then coupled, and the resulting system is modeled. A velocity sensor is developed and used in feedback compensation. The resulting speaker sy...

A direct adaptive nonlinear tracking control framework for multivariable nonlinear uncertain systems with actuator amplitude and rate saturation constraints is developed. To guarantee asymptotic stability of the closed-loop tracking error dynamics in the face of amplitude and rate saturation constraints, the adaptive control signal to a given reference (governor or supervisor) system is modifie...

This article focuses on theoretical developments in modeling and control of High-Speed Supercavitating Vehicles (HSSV). A simplified model of longitudinal dynamics is developed for control, and a dynamic inversion based inner-loop control technique is proposed to handle the switched, time-delay dependent behavior of the vehicle. Two outer-loop control schemes are compared for guidance level tra...

The piezo tutorial "Actuators for dynamic applications" or Actuator 2 describes dynamic applications, where dynamics (acceleration, damping) can be neglected. However, in many applications, dynamics play an important role and have to be taken into account in the design process. The tutorial gives an introduction to dynamic applications. Also the Mason model used to model, analyze and estimate t...

In this paper, a combined adaptive-robust and neural network control based on backstepping design is proposed for trajectory tracking of two 6-DOF rigid link electrically driven (RLED) elbow robot manipulators moving a rigid object when actuator dynamics is also considered in the system dynamics. First, the authors derive kinematics and dynamics of the mechanical subsystem and the relations amo...

Wireless sensor-actuator networks (WSANs) refer to a group of sensors and actuators linked by a wireless medium to perform distributed sensing and acting tasks. In order to provide effective sensing and acting, coordination mechanisms are required among sensors and actuators. We have presented the architectural design of a self organizing coordination framework in [3]. The framework organizes t...

Two electro-mechanical actuators are examined for a semi­ active Helmholtz resonator acoustic device. The device is used to reflect narrowband noise back to the source in an acoustic duct. The controller and actuator are used to tune the system on-line allowing optimum performance over a range of operating conditions. Actuator. dynamics play an important role in the controller design and the op...

This paper summarizes the formulation of two distinct methods for high-bandwidth nonlinear adaptive flight control of an unmanned helicopter testbed, and presents an evaluation and comparison of the two controllers in both simulation and flight test when subject to unmodeled dynamics, time delay, and actuator position and rate saturation. The attitude command system functions as an inner loop, ...

Conjugated polymer actuators can be employed to achieve micro and nano scale precision, and have wide range of applications including biomimetic robots and biomedical devices. In comparison to robotic joints, they do not have friction or backlash, but on the other hand, they have complicated electro-chemo-mechanical dynamics which makes modeling and control of the actuator really difficult. Bes...

Gao, Xiuyu. Ph.D., Purdue University, December 2012. Development of a Robust Framework for Real-time Hybrid Simulation: from Dynamical System, Motion Control to Experimental Error Verification. Major Professor: Shirley Dyke. Real time hybrid simulation (RTHS) has increasingly been recognized as a powerful methodology to evaluate structural components and systems under realistic operating condit...