Showing papers on "Bounding overwatch published in 1996"

Ellipsoidal Calculus for Estimation and Control

Abstract: This text gives an account of an ellipsoidal calculus and ellipsoidal techniques that allows presentation of the set-valued solutions to these problems in terms of approximating ellipsoidal-valued functions. Such an approach leads to effective computation schemes, an dopens the way to applications and implementations with computer animation, particularly in decision support systems. The problems treated here are those that involve calculation of attainability domains, of control synthesis under bounded controls, state constraints and unknown input disturbances, as well as those of "viability" and of the "bounding approach" to state estimation. The text ranges from a specially developed theory of exact set-valued solutions to the description of ellipsoidal calculus, related ellipsoidal-based methods and examples worked out with computer graphics. the calculus given here may also be interpreted as a generalized technique of the "interval analysis" type with an impact on scientific computation.

State bounding with ellipsoidal set description of the uncertainty

Abstract: The paper presents recursive algorithms for state bounding, using ellipsoidal sets to describe the state uncertainties and to bound the process and observation noises The algorithms optimize each stage of updating, according to the minimum-volume and minimum-trace criteria Simulations compare the performance of the bounding algorithms with that of a Kalman filter, and investigate the influence of noise distribution within the bounds

System and method using bounding volumes for assigning vertices of envelopes to skeleton elements in an animation system

Abstract: A system and method for assigning the vertices of an envelope to one or more elements of a skeleton in an animation model. Bounding volumes are defined for skeleton elements and define effective volumes which are positioned relative to the skeleton elements to encompass one or more vertices of envelopes. The bounding volume geometry may be defined as desired and a desired assignment operation type is selected for the bounding volume. When automated assignment is performed, assignment of the vertices within the bounding volumes is performed in accordance with the selected assignment operation for each bounding volume and with a selected maximum number of elements to which each vertex may be assigned. Bounding volumes may be overlapped to provide versatile automated assignment and the bounding volumes and corresponding assignment operations are stored with the skeleton and therefore are independent of the envelopes employed. Thus, the bounding volumes and assignment operations can be used both for the assignment of pre-production quality, low resolution, envelopes and for the subsequent assignment of production quality, high resolution, envelopes, as desired.

Homogeneous bounding boxes as tools for intersection algorithms of rational bézier curves and surfaces

Abstract: In the divide-and-conquer algorithm for detecting intersections of parametric rational Bezier curves (surfaces), we use bounding boxes in recursive rough checks. In this paper, we replace the conventional bounding box with a homogeneous bounding box, which is projectively defined. We propose a new rough check algorithm based on it. One characteristic of the homogeneous bounding box is that it contains a rational Bezier curve (surface) with weights of mixed signs. This replacement of the conventional bounding box by the homogeneous one does not increase the computation time.

Bounding the Transient Response of Structures to Uncertain Disturbances

Abstract: An analytical method is presented for bounding the peak transient response of a structure to an arbitrary, dynamic input force vector of given total magnitude. Since the method is based on the linear operator norm for the multivariable impulse response of the structural system, it does not require either a simulation or a numerical search to bound the worst-case response. Instead, the bound is computed directly from the structural eigenmodes. The method reported in this paper is a generalization of existing bounding methods for single-input/single-output methods to the more practical case of vector-valued forces and vector-valued responses. In addition, the paper presents a method for computing one of the possible input force vector tune histories that will excite a structural response equal to the bounded value. This worst-case input force is proposed as a candidate for force time histories to be used in structural qualification testing.