document

A MATLAB program to study gust loading on a simple aircraft model

Vink, W.J. (author), de Jonge, J.B. (author)

The present report is part of a "Manual" on aircraft loads, that is being prepared by NLR. It contains a computer program, to be used in combination with "MATLAB4 for Windows" (Student Edition) software, to study aircraft loading due to turbulence. It includes a simple aircraft response model with two rigid and three flexible symmetric degrees...

report 1997

document

Classical HPCN geared to application in industry

Verwer, J. (author), Loeve, W. (author), Snijdoodt, E. (author), ten Dam, A. (author)

In The Netherlands as a result of a national HPCN initiative a Foundation HPCN was established in 1995. The purpose of this Foundation is to stimulate structural and lasting cooperation of universities, technological institutes and industry in economically relevant applications of HPCN. Projects have been selected and since the beginning of 1996...

report 1997

document

Dynamics and control of a spacecraft with a moving, pulsating ball in a spherical cavity

Vreeburg, J.P.B. (author)

A model with two interacting bodies, for a spacecraft with liquid, has been developed. The spacecraft without liquid is the "tank" and is characterized by its inertial properties and the location and size of a spherical cavity. In the cavity is located the "slug", a sphere of uniform density with a variable radius. At the point of contact...

report 1996

document

On the simulation of fluid spacecraft interactive dynamics

Guelman, M. (author)

The present report contains a study on the simulation of interactive fluid spacecraft dynamics. The equations of motion of the two dimensional full tank case as well as the corresponding finite different discretized equations are presented. The numerical solution of this system is studied. Results are presented for a number of cases. Based on...

report 1993

document

Dynamics motion simulation of the Hermes robot arm subjected to constraints

Couwenberg, H.J.H. (author), ten Dam, A.A. (author)

During operations with a manipulator arm situations will occur when the manipulator end-effector is, or comes, in contact with its environment. The dynamics equations, which describe the motion of the manipulator, can be represented by an ordinary differential equation for the free motion and an additional algebraic (in)equality for the motion...

report 1990

document

Linear recursive formulation of flexible multi-body space system dynamics

van Woerkom, P.T.L.M. (author)

Numerical simulation of the dynamics of multi-body systems constitutes a central part in the design and analysis of modern space-based systems. The report focuses on the development of a recursive formulation of the dynamics of flexible spacecraft-robotmanipulator systems, suitable for efficient numerical simulation. The rather well-established...

report 1990

document

Predesign of a simulator for inverse robot kinematics

Groothuizen, R.J.P. (author)

An inverse robot kinematics method is being developed that is to be applicable to any sequential rigid robot. In this report, first requirements are identified and a survey of existing methods is given. An. evaluation of these methods with respect to the requirements then shows that a method based on optimization is the best candidate. It...

report 1990

document

De plaats van de wiskundige bij de ontwikkeling van digitale simulatie-systemen voor toepassingen uit de "Computational physics"

van der Wees, A.J. (author), van den Berg, J.I. (author)

NLR mainly performs applied scientific research for use in the aerospace industry. In many cases the product has the form of an information system for the design, production and usage of aerospace vehicles. Within this context, the mathematician contributes, in cooperation with specialists from other disciplines such as aerodynamics, structures,...

report 1990

document

Numerical solution of dynamical systems with equality state-space constraints

ten Dam, A.A. (author)

Numerical simulation of constrained dynamical systems is known to exhibit stability problems even when the unconstrained system can be simulated in a stable manner. We show that not the constraints themselves, but the transformation of a continuous set of equations to a discrete set of equations is the true source of the stability problem....

report 1990

document

Study on efficient numerical time-integration methods for simulation of multi-body systems

ten Dam, A.A. (author), Dieleman, P. (author)

This report describes the results of an evaluation of numerical integration schemes to be used for the digital simulation of second order ordinary differential equations (ODE's) which are characteristic for multibody systems such as space manipulators. The study focuses on dedicated schemes for this type of systems. Main attention is paid to the...

report 1990

document

Quasi-recursive dynamics equations for spacecraft-based flexible robotic manipulators

van Woerkom, P.T.L.M. (author)

The report contains the development of the dynamics equations of a spacecraftmanipulator system with chain topology. The spacecraft may be flexible. The attached manipulator consists of an arbitrary number of links, connected by single degree-of-freedom rotational joints. None, any, or all of the links may be flexible. A rigid or flexible...

report 1990

document

Equivalent flexibility modelling for the recursive simulation of robot manipulator dymamics

van Woerkom, P.T.L.M. (author)

The report focuses on the mathematical modelling of the dynamics of spacecraft based manipulators displaying structural flexibility in their links. The equations of motion must be cast in a form suitable for efficient numerical simulation. Equations of motion found in literature are usually written in the form of an augmented system of...

report 1989

document

Flexible space-based robot modelling and real-time simulation

Prins, J.J.M. (author), Dieleman, P. (author), van Woerkom, P.T.L.M. (author)

The Hermes manipulation system (HERA) is a sophisticated space manipulator system, which has to perform tasks ranging from berthing to tool operation in various operational modes from fully automatic to purely manual. Development and qualification of such a space-based manipulator must be supported by computer simulation facilities. The HERA...

report 1989

document

The use of MEBAS in creating a simulation environment for compression and encryption

Kordes, F.L.G. (author), Schuurman, J.J. (author)

In order to get a better sight on the performance of compression and encryption algorithms under various conditions a simulation environment is needed. Within this simulation environment It must be possible to investigate the influence of code tables, channel characteristics and frame formats on the performance of the algorithms. In this report...

report 1989

document

Definition of P.S.D.-design loads for nonlinear aircraft

Noback, R. (author)

The Power Spectral Density (P.S.D.)-method is used to define design loads due to atmospheric turbulence. The design loads are calculated using linear transfer functions. These methods can not be used if the equations describing the behaviour of the aircraft are nonlinear. One method to define design loads for a nonlinear aircraft is by means of...

report 1989

document

A positioning system based on NAVSAT

de Reus, N.M. (author), Moek, G. (author), Olsder, G.J. (author)

A worldwide navigation system called NAVSAT is discussed. This positioning system is based on satellites which broadcast information which can be used by receivers of this Information to estimate their position. The motion of the users is modelled by splines. The estimation procedure is based on the extended Kalman filter approach.

report 1987

document

Investigation on MLS approach path interception and transition techniques: part II: flight simulator investigation

Erkelens, J.J. (author), van der Geest, P.J. (author)

Due to the wide coverage volume of MLS, in both azimuth and elevation, the system enables the introduction of new approach and terminal area procedures. For several years the NLR has been investigating the potential of MLS with respect to the execution of non-straight-in approaches. In an earlier theoretical study four MLS-guided interception...

report 1986

document

A perspective of mathematical simulation and optimization techniques in computer aided design

van den Dam, R.F. (author)

The central issue discussed in this paper is how a designer may profit from the use of mathematical simulation and optimization techniques. These techniques can be useful tools to support the designer in solving his design problem. The place and the potential of these techniques in the design process, as well as their use by the designer, are...

report 1985

document

Investigation on MLS approach path interception and transition techniques: part I: fast-time computer simulations

Erkelens, L.J.J. (author), van der Geest, P.J. (author), Hagenberg, T.H.M. (author), Schrier, D. (author), Pouwels, R. (author)

MLS provides the possibility to define non-straight-in approach paths and to use more advanced interception procedures. From an ATC point-of-view it became necessary to structure this capability as a prerequisite in order to make a realistic use of the potential capabilities of MLS. Four different MLS approach path interception procedures were...

report 1985

document

Simulation and optimization techniques in computer aided design

van den Dam, R.F. (author)

The use of numerical simulation and optimization techniques is rapidly expanding in all fields of engineering design. The place and the potential of these techniques in the design process, as well as their use by the designer, are discussed. The principles underlying these techniques are outlined and an overall view is given of the various...

report 1985