A position reference system for flight test, based on GPS/IRS integration

Nowadays, several flight test organizations recognize the potential of the Navstar Global Positioning System (GPS) for flight test trajectorydetermination. In 1990 the National Aerospace Laboratory of the Netherlands (NLR) started the development of a Position Reference System (PRS) based on an Inertial Reference System (IRS), updated by GPS...

Experiences with two GPS SPS receivers in northern Europe

Results are given of measurements with two hand-held GPS C/A- code SPS (Standard Positioning Service) receivers at thirty locations in Finland, Norway and Sweden. Comparison is made between computed positions by the receivers and positions on geographic maps. It is concluded that both receivers have pros en cons. A combination of the...

Dynamics motion simulation of the Hermes robot arm subjected to constraints

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...

DME-derived positions compared with MLS- and ILS-derived positions

From recorded Distance Measurement Equipment (DME) data during Microwave Landing System (MLS) flight trials performed at London Gatwick Airport (April 21 - 26, 1989) using the NLR Fairchild Metro II Laboratory Aircraft, the position of the aircraft was determined by post-processing and compared with the MLS- and ILS-derived positions. This...

A positioning system based on NAVSAT

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.

In-flight attitude estimations and control experiments with Iras based on modern control theory

One of the research activities of the Space Division of the National Aerospace Laboratory NLR is the application of modern estimation and control theory to spacecraft attitude control problems. Algorithms for spacecraft state estimation and attitude control, as well as for inertial-optical attitude determination have been developed previously...

Historical development of collision risk models for en-route air traffic

This lecture reviews the model studies that were made with the object to reduce en-route separation standards. It also describes the basic principles of the Reich model used in most of these studies and of the Minimum Navigation Performance Specification (MNPS). Paper presented at the Princeton University Conference 155, "Safety Issues in Air...

Improvement of the superposition of geographical data in KOSMOSS

Since mid 1982, the Royal Netherlands Meteorological Institute KNMI has to its possession a ground station (KOSMOSS), which receives and processes high resolution imagery, acquired from Tiros-N type weather satellites. To determine the weather positions in the images, the ground station is equipped with the capability to superpose, in real time,...

A simulation investigation on the feasibility of curved approaches under MLS guidance. Revised edition