The Boltzmann transport equation is used to calculate thermal and electrical conductivity of metal nanostructures with characteristic dimensions in the 25--500 nm range, near above Debye temperature. Thermal contributions from phonons electrons are considered. intrinsic effects electron-phonon, phonon-phonon, phonon-electron scattering, grain boundary surface interactions addressed. Excellent agreement found between model results available data reporting direct measurements nanowires,...

We present a general intrinsic tracking controller design for fully-actuated simple mechanical systems, when the configuration space is one of class Lie groups. first express state-feedback in terms function-the "error function"-satisfying certain regularity conditions. If an error function can be found, then smooth and bounded reference trajectory may tracked asymptotically from almost every initial condition, with locally exponential convergence. Asymptotic convergence condition referred...

This paper examines control strategies for electrostatically actuated microelectromechanical systems (MEMS), with the goals of using feasible measurements to eliminate pull-in bifurcation, robustly stabilize any desired operating point in capacitive gap, decrease settling time, and reduce overshoot. We show that input-output linearization, passivity-based design, theory port-controlled Hamiltonian lead naturally static output feedback device charge. formalizes extends previously reported...

A nanofabricated electrothermal test structure is reported for directly measuring the thermal conductivity of aluminum nanowires near room temperature. Interdigitated perturb an otherwise symmetric heater-sensor analogous to electrical bridge circuit. Nanowires studied are 100 nm thick with 75, 100, and 150 widths. Finite element simulation accounts complex device geometry. Thermal resistivity vary significantly nanowire dimensions. Electron transport equation models which adequately...

This paper presents a dynamic observer for class of simple mechanical systems on Lie groups. provides velocity estimates based configuration measurements. The is \textit{intrinsic}, so its performance does not depend the choice coordinates, and it \textit{coordinate free}, in sense that equations may be written explicitly without specifying coordinates space. Our main result obtained by specializing previous Aghannan Rouchon concerning estimation Riemannian manifolds to such specialization...

Operating regions of electrostatically-actuated microelectromechanical systems are limited by a bifurcation phenomenon called "snap-through" or "pull-in". It is known that charge feedback control can be employed to avoid this bifurcation. The performance such controllers may poor, especially if the natural damping system very low high. This paper discusses two possible strategies eliminate snap-through as well improve performance. A serious drawback these laws they require measurement device...

Abstract In this article, we design a backstepping control law based on geometric principles to swing up spherical pendulum mounted moving quadrotor. The available degrees of freedom in the vector also permit us position plane quadrotor parallel ground. problem addressed here is, indeed, novel and has many practical applications which arise during transport payload top modeling are coordinate‐free thus avoid singularity issues. treatment greatly simplifies both for system. action is verified...

Abstract This paper presents a geometric framework for the stabilization and control of general class electrostatically actuated mechanical systems. Microelectromechanical systems (MEMS), such as micromirrors, are one motivating application this work. There wavelengths applications interest lead to positioning requirements on order 40–100 nm. Furthermore, electrostatic actuation is poised be method choice emerging field nanoelectromechanical (NEMS), approach presented should applicable there...

With constant voltage control, use of the entire capacitive gap in analog operation electrostatically-actuated MEMS devices is restricted by a bifurcation phenomenon known as "pull in" or "snap through." It well that properly-sized series capacitor will eliminate this bifurcation. We re-visit result from viewpoint control theory, and show implements static charge feedback, can semi-globally stabilize any position gap. In fact, with output, system relative degree one, input-output...

This work presents an intrinsic formulation of observer for important class simple mechanical systems on a Lie group. Recently, Aghannan and Rouchon have formulated system general Riemannian manifold. The current paper specializes their result to the case where manifold is group, kinetic energy left invariant, velocity variables are be estimated based measurement configuration variables. These restrictions allow greatly simplified result, interest in its own right. Most significantly, no...

This paper applies geometric PID control for asymptotic tracking of a desired trajectory by hoop robot in the presence disturbances and uncertainties. The robot, consisting circular body rolling without slip along one-dimensional surface, is planar analog spherical robot. A variety coupled mechanical system may be used to actuate specifically considers two different actuators, one simple pendulum other an internal cart. controller requires plant system, does not satisfy this condition....

The zeroth and first laws of thermodynamics define the concepts thermal equilibrium energy. second law determines whether a particular transfer energy can occur. Collectively, these fundamental nature imply that closed collection thermodynamic subsystems will tend to equilibrium. This paper generalizes energy, entropy, temperature undirected directed networks single integrators, demonstrates how principles be applied design distributed consensus control algorithms for networked dynamical systems.

This paper presents a PID controller for fully actuated, left-invariant, mechanical systems on general Lie group. The class of problems solved includes tracking smoothly time-varying desired orientation rigid body with actuated attitude dynamics in two or three dimensions. If the reference velocity and unmodeled disturbance forces converge to constant values, then closed-loop system will be almost-globally exponentially stable. is robust errors variations inertial parameters actuator...

Abstract We propose a framework for synthesizing real-time trajectories wide class of coordinating multi-agent systems. The problems considered is characterized by the ability to decompose given formation objective into an equivalent set lower dimensional problems. These include so called radar deception problem and control that fall under keeping and/or reconfiguration tasks. decomposition makes approach scalable, computationally economical, decentralized. Most importantly, designed are...

We present a unified approach to decentralized formation control of network agents, where the agents are modeled in framework geometric mechanics. The naturally accommodates underactuation, second-order agent dynamics, and nonholonomic constraints. Overall objectives specified for virtual structure (VS), while individual defined relative VS. restate problem as coupled set local two-body problems. construct controller assuming independent solution problems, plus asymptotic consensus VS...

Feedback control of electrostatic microelectromechanical systems (MEMS) is significantly complicated by the presence parasitics. This paper considers stabilization a one-degree-of-freedom (1-DOF) piston actuator under influence capacitively coupled parasitic electrode. Previous work authors has shown that, in absence parasitics, passivity-based may be used to make any feasible equilibrium point this system globally asymptotically stable. However parasitics destabilize nominal closed-loop...

This paper presents flight test results that demonstrate the effectiveness of a locally exponential and almost-globally stable geometric PID controller for attitude stabilization. The is implemented on low cost off shelf Arduino based quadrotor platform. requires only rough estimate inertia tensor device. It entirely using onboard processor does not require any board sensing or processing. presented show nonlinear capable quickly stabilizing desired vertically upright configuration large...

Closed-loop control of electrostatic MEMS requires sensing to provide a feedback signal. We present an integrated sensor for charge and position that negligibly affects the open-loop dynamics, does not increase device footprint, may be easily fabricated. Numerical finite-element simulation, incorporating realistic field model, experimental results validate functionality sensor. Simulations show how used in conjunction with nonlinear full gap operation improved transient performance....

In this paper we present a trajectory generation scheme for approximate way point tracking nonholonomic differential wheeled mobile robot. The generated trajectories are guaranteed to satisfy the dynamics and minimizes jerk of center mass motion Minimizing is desirable ensure smoothness often necessary physical hardware limitations electromagnetic actuators, prevent undesirable induced vibrations, comfort passengers. problem naturally formulated in setting constrained optimal control...

We present a feedback linearization control for almost global output-feedback tracking class of underactuated vehicles, with guaranteed stable zero dynamics and steady-state error in the absence uncertainties. show that has significant robustness to parameter variations unmodelled bounded forces moments. The potential benefits approach are illustrated simulations.

Intrinsic controllers are invariant under the coordinates used for their representation. In case of rigid-body motion in two and three dimensions, intrinsic approach eliminates problems with singularity or over-parametrization that may occur specific choices such as Euler angles quaternions. PD combine almost-global stabilization a familiar intuitive design framework have been known several years. this paper we show how integral action be added to control. We apply result stabilize attitude...