A Robustness Analysis of Game-Theoretic CDMA Power Control (2008)
Xingzhe Fan, Murat Arcak, John T. Wen
This paper studies robustness of a gradient-type CDMA uplink power control algorithm with respect to disturbances and time-delays. This problem is of practical importance because unmodeled secondary...
Abstract-Flexure joints are frequently used in precision mo-tion stages and micro-robotic mechanisms due lo their monolithic construction. The joint compliance, howeyer, can affect the static and...
Adaptive scanning optical microscope (ASOM) for large workspace micro-robotic applications (2008)
Abstract — Manipulation and assembly tasks associated with micro-systems, biotechnology, and product miniaturization demand that robots increasingly operate at microscopic dimensions. This paper...
Parallel mechanisms frequently contain an unstable type of singularity that has no counterpart in serial mechanisms. When the mechanism is at or near this type of singularity, it loses the ability to...
Dynamic Modeling and Input Shaping of Thermal Bimorph MEMS Actuators (2008)
Dan O. Popa, Byoung Hun Kang, John T. Wen, Harry E. Stephanou, George Skidmore, Aaron Geisberger
Thermal bimorphs are a popular actuation technology in MEMS (Micro-Electro-Mechanical Systems). Their operating principle is based on differential thermal expansion induced by Joule heating. Thermal...
Abstract-Flexure joints are frequently used in precision mo-tion stages and micro-robotic mechanisms due lo their monolithic construction. The joint compliance, howeyer, can affect the static and...
A Novel Model Predictive Control Strategy for Affine Nonlinear Control Systems (2007)
Fernando Lizarralde, John T. Wen, Liu Hsu
This paper considers the stabilization problem for control-affine nonlinear systems. A gradient-based numerical method is proposed to solve this problem. A receding horizon strategy, from Model...
Feedback Stabilization of Nonholonomic Systems based on Path Space Iteration (2007)
Fernando Lizarralde, John T. Wen, Liu Hsu
: A class of iterative methods has recently been proposed for the path planning of nonholonomic systems. These methods iteratively warp an initial path to an acceptable final path by using...
Power control for multicell CDMA wireless networks: A team optimization approach (2005)
Tansu Alpcan, Xingzhe Fan, Murat Arcak, John T. Wen
We study power control in multicell CDMA wireless networks as a team optimization problem where each mobile attains at the minimum its individual fixed target SIR level and beyond that optimizes its...
Power Control for Multicell CDMA Wireless Networks: (2005)
Team Optimization Approach, Tansu Alpcan, Xingzhe Fan, Murat Arcak, John T. Wen
We study power control in multicell CDMA wireless networks as a team optimization problem where each mobile attains at the minimum its individual fixed target SIR level and beyond that optimizes its...
Power control for multicell CDMA wireless networks: A team optimization approach (2005)
Tansu Alpcan, Xingzhe Fan, Murat Arcak, John T. Wen
We study power control in multicell CDMA wireless networks as a team optimization problem where each mobile attains its individual fixed target SIR level by transmitting with minimum possible power...
Analysis and design of parallel mechanisms with flexure joints (2004)
Abstract — Flexure joints are frequently used in precision motion stages and micro-robotic mechanisms due to their monolithic construction. The joint compliance, however, can affect the static and...
lp stability and delay robustness of network flow control (2003)
Xingzhe Fan, Murat Arcak, John T. Wen
This paper studies robustness of Kelly’s source and link control laws in [1] with respect to disturbances and time-delays. This problem is of practical importance because of unmodeled flows, and...
A unifying passivity framework for network flow control (2003)
Abstract — Network flow control regulates the traffic between sources and links based on congestion, and plays a critical role in ensuring satisfactory performance. In recent studies, global...
A unifying passivity framework for network flow control (2003)
Abstract — Network flow control regulates the traffic between sources and links based on congestion, and plays a critical role in ensuring satisfactory performance. In recent studies, global...
A unifying passivity framework for network flow control (2003)
Abstract — Network flow control regulates the traffic between sources and links based on congestion, and plays a critical role in ensuring satisfactory performance. In recent studies, global...
A unifying passivity framework for network flow control (2003)
Network flow control regulates the traffic between sources and links based on congestion, and plays a critical role in ensuring satisfactory performance. In recent studies, global stability has been...
Successive Galerkin Approximation Of The Isaacs Equation. (1999)
Randal W. Beard, Timothy W. McLain, John T. Wen
. The successive Galerkin approximation (SGA) algorithm has recently been developed for approximating solutions to the Hamilton-Jacobi-Isaacs equation. The algorithm produces feedback control laws...
A New Model Predictive Control Strategy for Affine Nonlinear Control Systems (1999)
Fernando Lizarralde, John T. Wen, Liu Hsu
: This paper considers the stabilization problem for control-affine nonlinear systems. A gradient-based numerical method is proposed to solve this problem. A receding horizon strategy, from Model...
Passivity Motivated Controller Design for Flexible Structures. (1998)
When actuators and sensors on a controlled mechanical structure form naturally passive pairs, which usually requires physical collocation, very robust stabilizing controllers can be constructed. If...
Feedback Stabilization of Nonlinear Systems: a Path Space Iteration Approach (1997)
Fernando Lizarralde, John T. Wen, Liu Hsu
: In this paper we consider the feedback stabilization of nonlinear systems. The design methodology is based on a class of iterative methods, which has recently been proposed for the path planning...
Feedback Stabilization of Nonholonomic Systems in Presence of Obstacles (1996)
Fernando Lizarralde, John T. Wen
: A class of iterative methods have recently been proposed for the path planning of nonholonomic systems. These methods warp an initial path iteratively to an acceptable final path by using...
Attitude Control without Angular Velocity Measurement: A Passivity Approach (1996)
Fernando Lizarralde, John T. Wen
It is well known that the linear feedback of the quarternion of the attitude error and angular velocity globally stabilizes the attitude of a rigid body. In this note, we show that the angular...
Attitude Control without Angular Velocity Measurement: A Passivity Approach (1996)
Fernando Lizarralde, John T. Wen
It is well known that the linear feedback of the quaternion of the attitude error and the angular velocity globally stabilizes the attitude of a rigid body. In this note, we show that the angular...
Feedback stabilization of nonholonomic systems in presence of obstacles (1996)
John T. Wen, Lambda Dan Popa\lambda
1 Introduction Nonholonomic systems arise in mechanical systems subject to non-integrable velocity constraints or non-integrable conservation laws. These systems are challenging from the control...
Feedback Stabilization of Nonholonomic Systems based on Path Space Iteration (1995)
Fernando Lizarralde, John T. Wen
A class of iterative methods have recently been proposed for the path planning of nonholonomic systems. These methods warp an initial path iteratively to an acceptable final path by using...
Fernando Lizarralde, John T. Wen, Liu Hsu
A control scheme for the coordinated control of a Subsea vehicle/manipulator system is presented. The unit quaternion representation is used in a singularity free representation of the attitude. The...