This paper describes a new spatial operator algebra for the dynamics of general{topology rigid multibody systems. Spatial operators allow a concise and systematic formulation of the dynamical equations of motion of multibody systems and the development of e cient computational algorithms. Equations of motion are developed for progressively more complex systems: serial chains, topological trees,...

Consider the Cholesky factorization of a sparse symmetric positive de nite matrix, A = LL . The rst two steps use symbolic, graph-theoretic techniques to order A to reduce ll in L, and to determine the exact sparsity structure of L. The factor L is computed in a third \numeric factorization" step. The two leading schemes for numeric factorization are a blocked column-oriented scheme, and a mult...

In a previous paper we introduced a system of recursion operators for formulating pure logic programs, dispensing with explicit recursions. The recursion operators, some of which are similar to higher-order functions known from functional programming, take the form of quasi-higher order predicates. In this paper we identify a comprehensive class of logic programs called primitive recursive rela...

This work deals with the use of our recent generalized dispersive material (GDM) model built on Pade approximants that is applied to FDTD simulations of nanoplasmonic structures. In particular, our original formulation is compared to the classical recursive-convolution technique for the Lorentz oscillator using a complex recursive accumulator. The proposed GDM model is then used to simulate the...

The focus of this paper is to review hybrid recursive-complementarity formulations for multibody systems characterized by a large number of bilateral constraints which are frequently encountered in robotics. Here, hybrid implies the use of complementarity contact models with recursive forward dynamics schemes. Such formulations have a common underlying structure which can be applied to multibod...

This paper presents a recursive algorithm for the deadbeat predictive control that brings the output response to rest after a few time steps. The main idea is to put together the system identification process and the deadbeat control design into a unified step. It starts with reformulating the conventional multi-step output-prediction equation to explicitly include the coefficient matrices to w...

This paper describes a new spatial operator algebra for the dynamics of general{topology rigid multibody systems. Spatial operators allow a concise and systematic formulation of the dynamical equations of motion of multibody systems and the development of e cient computational algorithms. Equations of motion are developed for progressively more complex systems: serial chains, topological trees,...

We present an object calculus for structured concurrent programming, facilitating the implementation of typed binary protocols, known as sessions. Session types are based on a concept of duality of interactions, providing a powerful type-theoretic foundation for guaranteeing well-behaved parallel composition of communicating code. Our formalism extends the Abadi and Cardelli imperative object c...

A recently developed spatial operator algebra for manipulator modeling, control and tra-jectory design is discussed. The elements of this algebra are linear operators whose domain and range spaces consist of forces, moments, velocities, and accelerations. The eeect of these operators is equivalent to a spatial recursion along the span of a manipulator. Inversion of operators can be eeciently ob...

One of the main problems in the database area is to define query languages characterized by both high expressive power and ease of use. In this paper, we propose a system to query databases, using diagrams as a standard user interface. The system, called Query by Diagram* (QBD*), makes use of a conceptual data model, a query language on this model and a graphical user interface. The conceptual ...