Showing papers in "Journal of Dynamic Systems Measurement and Control-transactions of The Asme in 1993"
TL;DR: In this paper, the three principal control effects found in present controllers are examined and practical names and units of measurement are proposed for each effect and corresponding units for a classification of industrial processes in terms of two principal characteristics affecting their controllability.
Abstract: In this paper, the three principal control effects found in present controllers are examined and practical names and units of measurement are proposed for each effect. Corresponding units are proposed for a classification of industrial processes in terms of the two principal characteristics affecting their controllability. Formulas are given which enable the controller settings to be determined from the experimental or calculated values of the lag and unit reaction rate of the process to be controlled
5,412 citations
TL;DR: In this paper, a continuous time deterministic optimal preview control algorithm is applied to the lateral guidance of a vehicle for an automated highway, where the front wheel steering angle of the vehicle is controlled so that the vehicle follows the center for a lane with small tracking error and maintains good ride quality simultaneously.
Abstract: The continuous time deterministic optimal preview control algorithm is applied to the lateral guidance of a vehicle for an automated highway. In the lateral guidance problem, the front wheel steering angle of the vehicle is controlled so that the vehicle follows the center for a lane with small tracking error and maintains good ride quality simultaneously. A preview control algorithm is obtained by minimizing a quadratic performance index which includes terms representing the passenger ride quality as well as the lateral tracking error, each of these terms is multiplied by a frequency dependent weight. It is shown that the optimal preview control law consists of a feedback control term and two feedforward control terms. The feedforward preview control action significantly improves the tracking performance and ride quality. Frequency-domain analyses, as well as numerical simulation results, show the improvements achieved by using the preview control algorithm in both the frequency and time domains.
315 citations
TL;DR: The paper surveys applications of optimal control techniques to the design of active suspensions, starting from simple quarter-car, 1D models, which are followed by their half-Car, 2D, and full- car, 3D, counterparts.
Abstract: The paper surveys applications of optimal control techniques to the design of active suspensions, starting from simple quarter-car, 1D models, which are followed by their half-car, 2D, and full-car, 3D, counterparts. The emphasis is on Linear-Quadratic (LQ) optimal control and automotive vehicles
263 citations
TL;DR: In this article, the flexibility of the drives and structures of controlled motion systems is presented as an obstacle to be overcome in the design of high performance motion systems, particularly manipulator arms.
Abstract: The flexibility of the drives and structures of controlled motion systems are presented as an obstacle to be overcome in the design of high performance motion systems, particularly manipulator arms. The task and the measure of performance to be applied determine the technology appropriate to overcome this obstacle. Included in the technologies proposed are control algorithms (feedback and feed forward), passive damping enhancement, operational strategies, and structural design. Modeling of the distributed, nonlinear system is difficult, and alternative approaches are discussed. The author presents personal perspectives on the history, status, and future directions in this area.
205 citations
TL;DR: The use of function identification and adaptive control algorithms in learning controllers for robot manipulators and the similarities and differences between betterment learning schemes, repetitive controllers and adaptive learning schemes based on integral transforms are discussed.
Abstract: Learning control encompasses a class of control algorithms for programmable machines such as robots which attain, through an iterative process, the motor dexterity that enables the machine to execute complex tasks. In this paper we discuss the use of function identification and adaptive control algorithms in learning controllers for robot manipulators. In particular, we discuss the similarities and differences between betterment learning schemes, repetitive controllers and adaptive learning schemes based on integral transforms. The stability and convergence properties of adaptive learning algorithms based on integral transforms are highlighted and experimental results illustrating some of these properties are presented
183 citations
TL;DR: In this article, the analysis and control of nonlinear uncertain systems in which the uncertainties are modeled deterministically rather than stochastically is described, and the main applications are to mechanical/aerospace systems, such as robots and spacecraft.
Abstract: This paper describes some of my research in the analysis and control of nonlinear uncertain systems in which the uncertainties are modeled deterministically rather than stochastically. The main applications are to mechanical/aerospace systems, such as robots and spacecraft; the underlying theoretical approach is based on Lyapunov theory
176 citations
TL;DR: In this article, a new approach to control synthesis for robust robot operations in unstructured environments is presented, where the notion of terminal convergence is introduced and control laws based upon a new class of sliding modes, denoted terminal sliders, are developed.
Abstract: Many robotic systems would, in the future, be required to operate in environments that are highly unstructured and active, i.e., possessing means of self-actuation. Although a significant volume of results exist in model-based, robust and adaptive control literature, general issues pertinent to the performance of such control systems remain unresolved, e.g., feasibility of implementing high gain switches for control robustness. It is also pointed out that in certain applications, control switching can be very detrimental to the overall system. The primary focus of this paper is development of a new approach to control synthesis for robust robot operations in unstructured environments. To enhance control performance with full model information, we introduce the notion of terminal convergence, and develop control laws based upon a new class of sliding modes, denoted terminal sliders
173 citations
TL;DR: In this article, the use of cylinder pressure measurements from reciprocating internal combustion engines for real-time automotive engine control has been investigated for the last 20 years, including the measurement of spark liming, fuel-air ratio control, charge temperature measurements, and misfire detection.
Abstract: Research into the use of cylinder pressure measurements from reciprocating internal combustion engines for real time automotive engine control has been investigated for the last 20 years. The measurement has been investigated for spark liming, fuel-air ratio control, charge temperature measurements, and misfire detection. The cost of the sensors has inhibited widespread use in production vehicles; however, it was introduced in domestic Japanese production for spark control five years ago. Its use for misfire detection is also being actively considered
154 citations
TL;DR: In this paper, the proportional plus multiple delay control (P2MDC) is proposed to cancel the residual vibration of lightly damped servomechanisms in a robust manner, which involves the use of multiple time delays in conjunction with a proportional part.
Abstract: A method is presented to minimize residual vibration of structures or lightly damped servomechanisms. The method, referred to as the proportional plus multiple delay control, involves the use of multiple time delays in conjunction with a proportional part to cancel the dynamics of the system in a robust fashion. An interesting characteristic of the controller involves addition of a basic single time-delay control unit in cascade to the existing controller, for every additional requirement of robustness
151 citations
TL;DR: In this paper, the existence and location of dynamic singularities cannot be predicted solely from the manipulator kinematic structure because they are functions of the dynamic properties of the system, unlike the singularities for fixed-base manipulators.
Abstract: Dynamic Singularities are shown for free-floating space manipulator systems where the spacecraft moves in response to manipulator motions without compensation from its attitude control system. At a dynamic singularity the manipulator is unable to move its end-effector in some inertial direction; thus dynamic singularities must be considered in the design, planning, and control of free-floating space manipulator systems. The existence and location of dynamic singularities cannot be predicted solely from the manipulator kinematic structure because they are functions of the dynamic properties of the system, unlike the singularities for fixed-base manipulators. Also analyzed are the implications of dynamic singularities to the nature of the system’s workspace.
146 citations
TL;DR: The structured singular value as discussed by the authors is a linear algebra tool developed to study a particular class of matrix perturbation problems arising in robust feedback control of multivariable systems, called linear fractional, and is a natural way to model many types of uncertainty in linear systems.
Abstract: The structured singular value is a linear algebra tool developed to study a particular class of matrix perturbation problems arising in robust feedback control of multivariable systems. These perturbations are called linear fractional, and are a natural way to model many types of uncertainty in linear systems, including state-space parameter uncertainty, multiplicative and additive unmodeled dynamics uncertainty, and coprime factor and gap metric uncertainty. The structured singular value theory provides a natural extension of classical SISO robustness measures and concepts to MIMO systems. The structured singular value analysis, coupled with approximate synthesis methods, make it possible to study the tradeoff between performance and uncertainty that occurs in all feedback systems. In MIMO systems, the complexity of the spatial interactions in the loop gains make it difficult to heuristically quantify the tradeoffs that must occur. This paper examines the role played by the structured singular value (and its computable bounds) in answering these questions, as well as its role in the general robust, multivariable control analysis and design problem.
TL;DR: In this article, the authors describe their work on the design of digital tracking controllers over the past two decades, and discuss tracking control for the following two typical situations: one is the situation where the desired output is known in advance and the other is where the target output itself is not known but has a certain known property, e.g., it is periodic with a know period.
Abstract: This paper describes my work on the design of digital tracking controllers over the past two decades. In tracking control, the control object must be moved along a time varying desired output and the transient path error must be minimized. Tracking control is discussed for the following two typical situations: one is the situation where the desired output is known in advance and the other is where the desired output itself is not known but has a certain known property, e.g., it is periodic with a know period
TL;DR: In this article, an analytical technique for vehicle handling qualities assessment is briefly discussed, along with a driver/vehicle steering model that contains both preview and compensatory steering dynamics and is used to evaluate the overall validity of the model.
Abstract: The resulting model is shown capable of producing driver/vehicle steering responses which compare favorably with those obtained from driver simulation. The model is simple enough to be used by engineers who may not be manual control specialists. The model contains both preview and compensatory steering dynamics. An analytical technique for vehicle handling qualities assessment is briefly discussed. Driver/ vehicle responses from two driving tasks evaluated in a driver simulator are used to evaluate the overall validity of the driver/vehicle model
TL;DR: In this paper, the authors reviewed the important recent research contributions for control of machining processes (e.g., turning, milling, drilling, and grinding) from the perspective of a hierarchical control system which considers servo, process, and supervisory control levels.
Abstract: This paper reviews the important recent research contributions for control of machining processes (e.g., turning, milling, drilling, and grinding). The major research accomplihsments are reviewed from the perspective of a hierarchical control system structure which considers servo, process, and supervisory control levels. The use and benefits ad advanced control methods (e.g., optimal control, adaptive control) are highlighted and illustrated with examples from research work conducted by the authors
TL;DR: In this paper, the velocity command input generated by repetitive control is used to learn the control input which eliminates errors caused by stiction, a subclass of learning control, and demonstrate that near-perfect tracking can be achieved in twelve cycles or less.
Abstract: One of the most significant sources of tracking error for an X-Y table is static friction, a nonlinear disturbance at low velocity. In traversing a circular profile, an X-Y table encounters zero velocity crossings at ninety degree intervals around the circle, leaving relatively large tracking errors referred to as “quadrant glitches.” To learn the control input which eliminates errors caused by stiction, repetitive control, a subclass of learning control, is employed. Experiments, conducted on the X-Y bed of a CNC milling machine, demonstrate that near-perfect tracking can be achieved in twelve cycles or less. Of particular interest is the velocity command input generated by repetitive control. The input contains feedforward information for developing perfect trajectories at low velocities.
TL;DR: In this paper, a method for limiting vibration in flexible systems that have more than one characteristic frequency and mode is described, and simple tests are established to determine when this technique can be used and examples are presented.
Abstract: This paper describes a method for limiting vibration in flexible systems that have more than one characteristic frequency and mode. It is only necessary to have knowledge of the component mode frequencies and damping ratios in order to be able to calculate the timing and magnitudes of the impulse sequence used in the shaping. Only two impulses, in the nonrobust case, or three impulses in a more robust case, are necessary regardless of the number of component frequencies. Simple tests are established to determine when this technique can be used and examples are presented.
TL;DR: In this article, a model-based approach to the recognition of discrete state transitions for robotic assembly is presented, in which sensor signals are interpreted with reference to the physical model of an assembly process in order to recognize the state of assembly in real time.
Abstract: This paper presents a model-based approach to the recognition of discrete state transitions for robotic assembly. Sensor signals, in particular, force and moment, are interpreted with reference to the physical model of an assembly process in order to recognize the state of assembly in real time. Assembly is a dynamic as well as a geometric process. Here, the model-based approach is applied to the unique problems of the dynamics generated by geometric interactions in an assembly process. First, a new method for the modeling of the assembly process is presented. In contrast to the traditional quasi-static treatment of assembly, the new method incorporates the dynamic nature of the process to highlight the discrete changes of state, e.g., gain and loss of contact
TL;DR: In this paper, the authors discuss the dynamic analysis and control of the lateral and longitudinal motions of a moving web which correspond to fluctuations perpendicular and parallel, respectively, to the primary direction of web transport.
Abstract: A web refers to any material in continuous flexible stripform which is either endless or very long compared to its width, and very wide compared to its thickness. The paper discusses the dynamic analyse and control of the lateral and longitudinal motions of a moving web which correspond to fluctuations perpendicular and parallel, respectively, to the primary direction of web transport. Historical perspectives are provided, from the early work of Osborne Reynolds in the late 1800s to current research. An overview of the control of both lateral and longitudinal web motion, which includes the control of tension, is presented. Present limitations in understanding and controlling lateral and longitudinal web behavior are discussed
TL;DR: In this paper, a modification of the conventional minimum variance state estimator is presented to accommodate the effects of randomly varying delays in arrival of sensor data at the controller terminal, where the currently available sensor data is used at each sampling instant to obtain the state estimate which can be used to generate the control signal.
Abstract: This paper presents a modification of the conventional minimum variance state estimator to accommodate the effects of randomly varying delays in arrival of sensor data at the controller terminal. In this approach, the currently available sensor data is used at each sampling instant to obtain the state estimate which, in turn, can be used to generate the control signal. Recursive relations for the filter dynamics have been derived, and the conditions for uniform asymptotic stability of the filter have been conjectured
TL;DR: In this paper, a personal history of one area of research with which I have been concerned over the past twenty years and which continues to attract my albeit waning attention, the control of dynamical systems based on uncertain models is presented.
Abstract: This paper is a personal history of one area of research with which I have been concerned over the past twenty years and which continues to attract my albeit waning attention, the control of dynamical systems based on uncertain models. Thus, it is a subjective account of various factors which I believe to have steered me to approach the problem via a constructive use of Lyapunov stability theory
TL;DR: In this paper, a low-frequency lumped-parameter mathematical model of the hydraulic mount is developed over 1 to 50 Hz, based on the measured nonlinear system parameters such as the steadystate inertia track fluid resistances and fluid chamber compliances.
Abstract: Nonlinear properties of a generic hydraulic mount with an inertia track are identified and characterized by using experimental and analytical approaches. A low-frequency lumped-parameter mathematical model of the hydraulic mount is developed over 1 to 50 Hz, based on the measured nonlinear system parameters such as the steadystate inertia track fluid resistances and fluid chamber compliances. New experiments specifically designed for this study are also described. The effect of temperature on the mount dynamic properties is discussed briefly
TL;DR: In this article, a theoretical development of generic piezoelectric shell distributed systems is presented, denoted by a new theoretical development for generic piezo-lectric shells distributed systems.
Abstract: This paper is denoted to a new theoretical development of generic piezoelectric shell distributed systems. System electromechanical equations and boundary conditions for a thick piezoelectric shell continuum with symmetrical hexagonal structure (Class C 6v =6 mm) are derived using Hamilton's principle and linear piezoelectric theory. Further simplification leads to a set of new electromechanical system equations, three translated coordinates and two rotary coordinates, for piezoelectric shell continua including rotary inertias and transverse shears
TL;DR: In this paper, a tracking control law for multijoint flexible-link manipulators is described, where passive joint controllers, together with the feedforward of nominal joint torques corresponding to a desired end-effector trajectory, results in exponentially stable tracking control.
Abstract: In this paper we describe a new tracking control law for multijoint flexible-link manipulators. The scheme is a synthesis of the inverse dynamics solution for flexible manipulators developed by Bayo at UCSB and tracking control theory for rigid-link manipulators put forth by Bayard, Wen and others. We show that passive joint controllers, together with the feedforward of nominal joint torques corresponding to a desired end-effector trajectory, results in exponentially stable tracking control
TL;DR: In this article, several methodologies are proposed for identifying the dynamics of a machine tool feed drive system in the low frequency region, including linear models described by output-error (OE) and Autoaggressive Miving Average with eXogeneous Input (ARMAX) models.
Abstract: Several methodologies are proposed for identifying the dynamics of a machine tool feed drive system in the low frequency region. An accurate indentification is necessary for the desing of a feedforward tracking controller, which achieves unity gain and zero phase shift for the overall system in the relevant frequency band. In machine tools and other mechanical systems, the spectrum of the reference trajectory is composed of low frequency signals. Standard least squares fits are shown to heavily penalize high frequency misfit. Linear models described by the output-error (OE) and Autoaggressive Miving Average with eXogeneous Input (ARMAX) models display better closeness-of-fit properties at low frequency
TL;DR: In this paper, the active noise control of a one-dimensional hard-walled duct with a partially dissipative boundary condition is addressed by applying modern, state space, control theory to globally reduce noise levels in a 1D acoustic enclosure rather than at a single location.
Abstract: The active noise control of a one-dimensional hard-walled duct with a partially dissipative boundary condition is addressed. Previous techniques have attacked this problem by developing adaptive filters designed to cancel acoustic noise at a single measurement location. The work presented here applies modern, state space, control theory to globally reduce noise levels in a one-dimensional acoustic enclosure rather than at a single location. This global control requires only the addition of a single response measurement microphone and control speaker to the open-loop system
TL;DR: In this paper, a variable structure control law based on the Lyapunov's second method was developed for trajectory planning problems of robotic systems, and a modified approach to the formulation of the sliding domain equations in terms of tracking errors was presented.
Abstract: A new variable structure control law based on the Lyapunov's second method that can be used in trajectory planning problems of robotic systems is developed. A modified approach to the formulation of the sliding domain equations in terms of tracking errors has been presented. This approach possesses three distinct advantages: (i) it eliminates the reaching phase, (ii) it provides means to predict the entire motion and directly control the evolution of tracking errors, (iii) it facilitates the trajectory planning process in the joint and/or cartesian spaces. A planar, five-link bipedal locomotion model has been developed
TL;DR: In this paper, the authors investigate the dynamics of nanometer motion of a ball screw and show that the observed dynamics are nonlinear, and consequently result in inconsistent and unpredictable closed-loop response while under PI position control.
Abstract: A desire to improve the positioning accuracy of ball screws prompted an investigation into the dynamics of nanometer motion. Characterization of the ball screw indicated that nanometer motion is possible prior to friction breakaway via elastic deformation of the frictional contacts while macroscopic motion involves slipping across the friction interfaces. The observed dynamics are nonlinear, and consequently result in inconsistent and unpredictable closed-loop response while under PI position control. The ball-screw can be modeled in two stages: The microdynamic stage includes «elastic» friction while the macrodynamic stage incorporates kinetic (sliding) friction
TL;DR: In this paper, a semi-active suspension control algorithm was proposed to reduce dynamic tire forces. But the application of observers for bilinear systems with unknown disturbances was not considered.
Abstract: This paper presents a semiactive suspension control algorithm to reduce dynamic tireforces and it includes the development and application of observers for bilinear systems with unknown disturbances. The peak dynamic tire forces, which are greatly in excess of static tire forces, are highly dependent on the dynamic characteristics of vehicle suspensions. One way to reduce dynamic tire forces is to use advanced suspension systems such as semiactive suspensions. Semiactive control laws to reduce dynamic tire forces are investigated and a bilinear observer structure for bilinear systems with unknown disturbances is formulated such that the estimation error is independent of the unknown external disturbances and the error dynamics are stable for bounded inputs
TL;DR: Some analytical derivations related to neural networks and fuzzy optimal control as elements of proposed intelligent control systems, along with experimental results, are presented.
Abstract: The fundamental concept of feedback to control dynamic systems has played a major role in many areas of engineering. Increases in complexity and more stringent requirements have introduced new challenges for control systems. This paper presents an introduction to and appreciation for intelligent control systems, their application areas, and justifies their need. Specific problem related to automated human comfort control is discussed. Some analytical derivations related to neural networks and fuzzy optimal control as elements of proposed intelligent control systems, along with experimental results, are presented. A brief glossary of common terminology used in this area is included
TL;DR: In this article, an adaptive controller for a one-degree-of-freedom pneumatic actuator is presented, which uses full-state feedback for simultaneous parameter identification and tracking control.
Abstract: An adaptive controller is presented for a one-degree-of-freedom pneumatic actuator. The control law uses full-state feedback for simultaneous parameter identification and tracking control. For position control, a pneumatic actuator with high bandwidth is difficult to obtain because of the compressibility of air and the nonlinear characteristics of air flowing through a variable area orifice. Most previous controllers for gas powered actuators were relatively limited fixed gain or on-off type controllers with low tracking accuracy. Experimental results demonstrate that tracking performance comparable to electric servomotors can be obtained using the algorithm presented despite the nonlinearities and compressibility of air