Author
N.H. McClamroch
Other affiliations: Worcester Polytechnic Institute, University of Texas at Austin
Bio: N.H. McClamroch is an academic researcher from University of Michigan. The author has contributed to research in topics: Nonlinear system & Control system. The author has an hindex of 30, co-authored 118 publications receiving 6317 citations. Previous affiliations of N.H. McClamroch include Worcester Polytechnic Institute & University of Texas at Austin.
Papers published on a yearly basis
Papers
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02 Jun 1999
TL;DR: This work designs a feedback controller so that the controlled vehicle accomplishes a given planar maneuver, that is a change in the translational velocity vector and the attitude of the vehicle, while rapidly attenuating any relative motion of the internal degree of freedom.
Abstract: We study feedback control laws that enable an aerospace vehicle to perform planar maneuvers. We make several key assumptions including: (1) maneuvers are planar, (2) a complete set of vehicle control forces and moments is available, (3) the vehicle is a rigid body with a single unactuated internal degree of freedom. The control objective is to design a feedback controller so that the controlled vehicle accomplishes a given planar maneuver, that is a change in the translational velocity vector and the attitude of the vehicle, while rapidly attenuating any relative motion of the internal degree of freedom. A time-invariant discontinuous feedback law is constructed that achieves these control objectives with exponential convergence rates. The effectiveness of the proposed feedback law is illustrated through a simulation example.
8 citations
15 Dec 1993
TL;DR: In this article, an asymptotic output tracking problem for a class of nonlinear control systems with fewer outputs than inputs is studied, and conditions for when this approach is successful.
Abstract: An asymptotic output tracking problem is studied for a class of nonlinear control systems with fewer outputs than inputs. The development is based on a standard relative degree assumption. The most interesting feature of the development is that the extra control degrees of freedom can be used to influence the closed loop characteristics, including the zero dynamics. Conditions are developed for when this approach is successful. >
7 citations
TL;DR: In this paper, the authors address the question of design and optimal control of a class of dual-spacecraft interferometric imaging formations and propose a maneuver that offers improved imaging performance.
Abstract: We address the question of design and optimal control of a class of dual-spacecraft interferometric imaging formations. The first main contribution is that we combine two ideas introduced separately in the literature and propose a maneuver that offers improved imaging performance. We then formulate an optimal control problem to minimize fuel consumption and maximize image quality by minimizing the relative speed, which is proportional to the signal-to-noise ratio (SNR) of the reconstructed image. We show that the necessary conditions are also sufficient and that the resulting optimal control is unique. Finally, we apply a continuation method to solve for the unique optimal trajectory.
7 citations
09 Dec 2003
TL;DR: In this article, a rigid body, supported by a fixed pivot point, is free to rotate in three dimensions, and conditions that guarantee asymptotic stability for relevant equilibrium solutions are presented.
Abstract: A rigid body, supported by a fixed pivot point, is free to rotate in three dimensions. Two cases are studied: the balanced case, whose dynamics are described by the Euler equations for a free rigid body, and the unbalanced case, whose dynamics are described by the heavy top equations. Both cases include linear passive dissipation effects. For each case, conditions are presented that guarantee asymptotic stability for relevant equilibrium solutions. The developments are based on a careful treatment of nonlinear coupling in applying LaSalle's invariance principle. Emphases are given to the partial damping cases; an approach based on the polynomial structure of the dynamics is used to obtain asymptotic stability conditions for these cases.
7 citations
01 Dec 2007
TL;DR: This work considers a spacecraft formation reconfiguration problem in the case of identical spacecraft and proposes a coupled combinatorial and continuous optimization framework, in which the inner loop consists of computing the costs associated with a particular assignment by using a geometrically exact and numerically efficient discrete optimal control method based on Lie group variational integrators.
Abstract: We consider a spacecraft formation reconfiguration problem in the case of identical spacecraft. This introduces in the optimal reconfiguration problem a permutational degree of freedom, in addition to the choice of individual spacecraft trajectories. We approach this non-convex optimization problem using a coupled combinatorial and continuous optimization framework, in which the inner loop consists of computing the costs associated with a particular assignment by using a geometrically exact and numerically efficient discrete optimal control method based on Lie group variational integrators. In the outer optimization loop, combinatorial optimization techniques are used to determine the optimal assignments based on the costs computed in the inner loop. The proposed method is demonstrated on the optimal reconfiguration problem for 5 identical spacecraft to go from an inline configuration to one equally spaced on a circle.
7 citations
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Book•
22 Mar 1994
TL;DR: In this paper, the authors present a detailed overview of the history of multifingered hands and dextrous manipulation, and present a mathematical model for steerable and non-driveable hands.
Abstract: INTRODUCTION: Brief History. Multifingered Hands and Dextrous Manipulation. Outline of the Book. Bibliography. RIGID BODY MOTION: Rigid Body Transformations. Rotational Motion in R3. Rigid Motion in R3. Velocity of a Rigid Body. Wrenches and Reciprocal Screws. MANIPULATOR KINEMATICS: Introduction. Forward Kinematics. Inverse Kinematics. The Manipulator Jacobian. Redundant and Parallel Manipulators. ROBOT DYNAMICS AND CONTROL: Introduction. Lagrange's Equations. Dynamics of Open-Chain Manipulators. Lyapunov Stability Theory. Position Control and Trajectory Tracking. Control of Constrained Manipulators. MULTIFINGERED HAND KINEMATICS: Introduction to Grasping. Grasp Statics. Force-Closure. Grasp Planning. Grasp Constraints. Rolling Contact Kinematics. HAND DYNAMICS AND CONTROL: Lagrange's Equations with Constraints. Robot Hand Dynamics. Redundant and Nonmanipulable Robot Systems. Kinematics and Statics of Tendon Actuation. Control of Robot Hands. NONHOLONOMIC BEHAVIOR IN ROBOTIC SYSTEMS: Introduction. Controllability and Frobenius' Theorem. Examples of Nonholonomic Systems. Structure of Nonholonomic Systems. NONHOLONOMIC MOTION PLANNING: Introduction. Steering Model Control Systems Using Sinusoids. General Methods for Steering. Dynamic Finger Repositioning. FUTURE PROSPECTS: Robots in Hazardous Environments. Medical Applications for Multifingered Hands. Robots on a Small Scale: Microrobotics. APPENDICES: Lie Groups and Robot Kinematics. A Mathematica Package for Screw Calculus. Bibliography. Index Each chapter also includes a Summary, Bibliography, and Exercises
6,592 citations
TL;DR: In this paper, the authors survey three basic problems regarding stability and design of switched systems, including stability for arbitrary switching sequences, stability for certain useful classes of switching sequences and construction of stabilizing switching sequences.
Abstract: By a switched system, we mean a hybrid dynamical system consisting of a family of continuous-time subsystems and a rule that orchestrates the switching between them. The article surveys developments in three basic problems regarding stability and design of switched systems. These problems are: stability for arbitrary switching sequences, stability for certain useful classes of switching sequences, and construction of stabilizing switching sequences. We also provide motivation for studying these problems by discussing how they arise in connection with various questions of interest in control theory and applications.
3,566 citations
Journal Article•
[...]
TL;DR: In this paper, two major figures in adaptive control provide a wealth of material for researchers, practitioners, and students to enhance their work through the information on many new theoretical developments, and can be used by mathematical control theory specialists to adapt their research to practical needs.
Abstract: This book, written by two major figures in adaptive control, provides a wealth of material for researchers, practitioners, and students. While some researchers in adaptive control may note the absence of a particular topic, the book‘s scope represents a high-gain instrument. It can be used by designers of control systems to enhance their work through the information on many new theoretical developments, and can be used by mathematical control theory specialists to adapt their research to practical needs. The book is strongly recommended to anyone interested in adaptive control.
1,814 citations
01 Jul 2000
TL;DR: In this paper, the authors introduce the concept of hybrid systems and some of the challenges associated with the stability of such systems, including the issues of guaranteeing stability of switched stable systems and finding conditions for the existence of switched controllers for stabilizing switched unstable systems.
Abstract: This paper introduces the concept of a hybrid system and some of the challenges associated with the stability of such systems, including the issues of guaranteeing stability of switched stable systems and finding conditions for the existence of switched controllers for stabilizing switched unstable systems. In this endeavour, this paper surveys the major results in the (Lyapunov) stability of finite-dimensional hybrid systems and then discusses the stronger, more specialized results of switched linear (stable and unstable) systems. A section detailing how some of the results can be formulated as linear matrix inequalities is given. Stability analyses on the regulation of the angle of attack of an aircraft and on the PI control of a vehicle with an automatic transmission are given. Other examples are included to illustrate various results in this paper.
1,647 citations
TL;DR: Nonholonomic control systems as discussed by the authors provide a good introduction to the subject for nonspecialists in the field, while perhaps providing specialists with a better perspective of the field as a whole.
Abstract: Provides a summary of recent developments in control of nonholonomic systems. The published literature has grown enormously during the last six years, and it is now possible to give a tutorial presentation of many of these developments. The objective of this article is to provide a unified and accessible presentation, placing the various models, problem formulations, approaches, and results into a proper context. It is hoped that this overview will provide a good introduction to the subject for nonspecialists in the field, while perhaps providing specialists with a better perspective of the field as a whole. The paper is organized as follows: introduction to nonholonomic control systems and where they arise in applications, classification of models of nonholonomic control systems, control problem formulations, motion planning results, stabilization results, and current and future research topics.
1,269 citations