Maurice F. Hutton

Bio: Maurice F. Hutton is an academic researcher from Singer Corporation. The author has contributed to research in topics: Angular displacement & Constant coefficients. The author has an hindex of 6, co-authored 7 publications receiving 643 citations.

Routh approximations for reducing order of linear, time-invariant systems

Abstract: A new method of approximating the transfer function of a high-order linear system by one of lower order is proposed. Called the "Routh approximation method" because it is based on an expansion that uses the Routh table of the original transfer function, the method has a number of useful properties: if the original transfer function is stable, then all approximants are stable; the sequence of approximants converge monotonically to the original in terms of "impulse response" energy; the approximants are partial Pade approximants in the sense that the first k coefficients of the power series expansions of the k th-order approximant and of the original are equal; the poles and zeros of the approximants move toward the poles and zeros of the original as the order of the approximation is increased. A numerical example is given for the calculation of the Routh approximants of a fourth-order transfer function and for illustration of some of the properties.

Theory and error analysis of vibrating-member gyroscope

Abstract: There is a general class of gyroscopic instruments that use a vibrating member as the sensitive element. Instruments in this class are governed by the differential equations \ddot{x} + \Omega^{2}x - c\omega\dot{y} = 0 \ddot{y} + \Omega^{2}y - c\omega\dot{x} = 0 which describe the position of a reference point on the vibrating member relative to a coordinate system fixed in the instrument case. The point (x,y) moves in an elliptical orbit with poriod 2\pi/\Omega . The orbit precesses at a rate -c\omega/2 (with c \leq 2 ) relative to the coordinate system and, hence, tends to remain fixed in inertial space. The differential equations for the orbital elements ( a =semimajor axis b =semiminor axis, φ=inclination, and \theta =orbital angle) are derived for a nonideal gyroscope with damping and anisoelasticity present. The difforential equations for the long-term effects are obtained by averaging the coefficients over the approximate period of oscillation. These equations can he transformed into a fourth-order system of linear differential equations with constant coefficients in the average energy and angular momentum, and their derivatives. These equations are solved explicitly for several cases of practical interest and the results are interpreted physically.

Control system for angular displacement sensor

Abstract: Stable reference gyroscopic apparatus is provided in the form of an angular displacement sensor which employs an end-supported vibratory rod or wire, instead of the commonly used rotatable element. The apparatus of the invention incorporates an improved means for maintaining the vibrational amplitude of the center of the vibratory element constant, and electronic circuit means for causing the orbit of center of the vibratory element to remain in a straight line, both means being effective to eliminate the major sources of potential drift in the sensor.

Quasi-optimum design of a six degree of freedom moving base simulator control system

Abstract: The design of a washout control system for a moving base simulator is treated by a quasi-optimum control technique. The broad objective of the design is to reproduce the sensed motion of a six degree of freedom simulator as accurately as possible without causing the simulator excursions to exceed specified limits. A performance criterion is established that weights magnitude and direction errors in specific force and in angular velocity and attempts to maintain the excursion within set limits by penalizing excessive excursions. A FORTRAN routine for relizing the washout law was developed and typical time histories using the washout routine were simulated for a range of parameters in the penalty- and weighting-functions. These time histories and the listing of the routine are included in the report.

Ellipticity control system for angular displacement sensor

Abstract: An ellipticity control system for controlling the elliptical deviation of the vibratory element of a displacement sensor. The apparatus incorporates a plurality of drive electrodes, at least six in number, mounted concentrically along the longitudinal axis of the elongated vibratory element. Each drive electrode is formed in pairs oriented along separate axes. A pair of X-axis pickoffs and a pair of Y-axis pickoffs axially spaced from the drive electrodes are also mounted concentrically of the vibratory element to sense the deviation of the vibratory element from null and to provide control signals by way of circuit means to the drive electrodes.

Load Frequency Control in Power Systems via Internal Model Control Scheme and Model-Order Reduction

Abstract: The large-scale power systems are liable to performance deterioration due to the presence of sudden small load perturbations, parameter uncertainties, structural variations, etc. Due to this, modern control aspects are extremely important in load frequency control (LFC) design of power systems. In this paper, the LFC problem is illustrated as a typical disturbance rejection as well as large-scale system control problem. For this purpose, simple approach to LFC design for the power systems having parameter uncertainty and load disturbance is proposed. The approach is based on two-degree-of-freedom, internal model control (IMC) scheme, which unifies the concept of model-order reduction like Routh and Pade approximations, and modified IMC filter design, recently developed by Liu and Gao [24]. The beauty of this paper is that in place of taking the full-order system for internal-model of IMC, a lower-order, i.e., second-order reduced system model, has been considered. This scheme achieves improved closed-loop system performance to counteract load disturbances. The proposed approach is simulated in MATLAB environment for a single-area power system consisting of single generating unit with a non-reheated turbine to highlight the efficiency and efficacy in terms of robustness and optimality.

Model reduction using the Routh stability criterion

Abstract: A new method of model reduction is introduced based on the Routh stability criterion. The reduced order transfer function is determined directly from elements in the Routh stability arrays of the high-order denominator and numerator. An eighth order example illustrates the accuracy of the method, the preservation of the frequency response and computational simplicity. The method is equally applicable to unstable systems.

Simulator motion-drive algorithms - A designer's perspective

Abstract: Changes in the design of software algorithms for generating physical motion in flight simulators have typically been put forward on the grounds of improved motion cueing. Little attention has been paid to more practical criteria such as computational cost, ease of adjustment, or evaluation by experienced pilots in a realistic simulation environment. A comparison of three of the algorithms most commonly found in the literature has been performed: classical washout, optimal control, and coordinated adaptive. This consisted of pilot evaluations of these algorithms implemented on a six-degree-of-freedom flight simulator simulating a large transport aircraft during low-altitude flight and ground maneuvering. This paper presents the results of that study from the designer's viewpoint. In it, we contend that, with enough effort, most algorithms can be massaged to perform reasonably well, and that a more important consideration is the ease with which a given algorithm can be brought to high performance levels. If this criterion is used, it appears that the classical algorithm is a good starting point, and that the benefits of an adaptive algorithm can be added gradually to obtain the advantages conferred by nonlinear filtering and "intelligent" cost functions.

Multiobjective genetic algorithms with application to control engineering problems.

Abstract: Genetic algorithms (GAs) are stochastic search techniques inspired by the principles of natural selection and natural genetics which have revealed a number of characteristics particularly useful for applications in optimization, engineering, and computer science, among other fields. In control engineering, they have found application mainly in problems involving functions difficult to characterize mathematically or known to present difficulties to more conventional numerical optimizers, as well as problems involving non-numeric and mixed-type variables. In addition, they exhibit a large degree of parallelism, making it possible to effectively exploit the computing power made available through parallel processing. Despite their early recognized potential for multiobjective optimization (almost all engineering problems involve multiple, often conflicting objectives), genetic algorithms have, for the most part, been applied to aggregations of the objectives in a single-objective fashion, like conventional optimizers. Although alternative approaches based on the notion of Pareto-dominance have been suggested, multiobjective optimization with genetic algorithms has received comparatively little attention in the literature. In this work, multiobjective optimization with genetic algorithms is reinterpreted as a sequence of decision making problems interleaved with search steps, in order to accommodate previous work in the field. A unified approach to multiple objective and constraint handling with genetic algorithms is then developed from a decision making perspective and characterized, with application to control system design in mind. Related genetic algorithm issues, such as the ability to maintain diverse solutions along the trade-off surface and responsiveness to on-line changes in decision policy, are also considered. The application of the multiobjective GA to three realistic problems in optimal controller design and non-linear system identification demonstrates the ability of the approach to concurrently produce many good compromise solutions in a single run, while making use of any preference information interactively supplied by a human decision maker. The generality of the approach is made clear by the very different nature of the two classes of problems considered.