Estimates of spacecraft attitude and sensor parameters using adaptive filtering: Meteosat-1 transfer orbit application

In practical applications of Kalman filtering theory often inconsistencies between real estimation errors and computed error variances occur due to modelling errors. An adaptive filtering technique has been developed at NLR to deal with this filter divergence problem. Special attention is paid to divergence detection. When divergence is detected...

Digital filtering methods, with applications to spacecraft attitude determination in the presence of modelling errors. Part II: Extension of theory, and applications

The present issue is the second and final part of a report describing the results of a study about digital filtering. The first part is available as the report NLR TR 760U8 U. The report considers a number of digital filtering methods and gives examples of their application. The methods include batch processing methods and recursive methods....

Processing of Meteosat attitude measurement flight data and evaluation of the performance of an adaptive filtering technique

The attitude measurement data of the ESA geosynchronous spacecraft METEOSAT have been analyzed using an adaptive recursive filtering technique developed at NLR. The mathematical models of spacecraft dynamics and sensors have been kept very simple. Modelling errors are such that, without adaptive feed-back, strong divergence of the filtering...

Accurate spacecraft attitude estimation with the ESA starmapper

The ESA starmapper is an optical-electronic instrument with an array of photo-sensitive slits, to "be strapped down to spinning spacecraft. Recorded times of passage of known stars over these slits, together with mathematical models for spacecraft dynamics and starmapper instrument, provide the basis for recursive estimation of the spacecraft...

Comparison of three state and parameter estimation methodfs, with a specialm view to modelling errors

Estimation of modelling errors in satellite attitude determination

Paper presented at the 27th Congress of the I.A.F., October 10-I6, 1976, Anaheim, USA.

Digital filtering methods, with applications to satellite attitude determination in the presence of modelling errors. Part I: theory

The report reviews a number of digital filtering methods and gives examples of their application. The methods include batch processing methods and rec\irsive methods, not only in the classical formulations but also in square-root formulations. The latter formulations have the purpose to prevent certain numerical inconveniences. Much attention is...

Analysis of a stepwise numerical method for solution of a three-dimensional flow problem

The simulation of a class of three-dimensional, stationary, supersonic gas flows by construction of an approximate solution to the governing system of partial differential equations, is analysed. The investigated method is a hybrid one: it involves finite difference calculations on a regular, orthogonal grid, and characteristics calculations,...

Error analysis for a satellite based air traffic control system

Program for the computation of axisymmetric supersonic flow around launch type vehicles, based on the method of characteristics

In this report a program in ALGOL (CDC-3300, MBOS (3,2) operating system) is described for the computation of the supersonic flow of a thermally and calorically perfect gas around axisymnetric bodies. Computational details are given and some numerical results are presented. Emphasis is placed on the organization of the program. For a specific...

Response to ESOC request for quotation Ref. RQ/153/72/AR: Study on a numerical orbit computation based on an intermediate orbit

High-order accuracy numerical integration of second-order ordinary differential equations by means of Nordsieck's method

An investigation has been performed to obtain a reliable and economical method for the numerical integration of second order ordinary differential equations of considerable complexity over a long interval. A Nordsieck process of 10th order has been selected for this purpose, A derivation of the process is given in this report. Stability and...

The accurate numerical calculation of the flow around blunt bodies (ideal gas and spherical shape) moving at supersonic speeds

An accurate inverse method for the numerical calculation of the supersonic flow around an axisymmetric blunt body is presented. By a suitable transformation the field under connideration is mapped on a rectangular strip. Integration of the equations of motion in the transformed domain is performed by simultaneous application of a third order...

Blunt body supersonic flow: Investigations about an inverse and a direct method

An accurate inverse method for the numerical computation of the supersonic flow around a blunt body, on the presupposition of ideal gas properties, is presented. By a suitable transformation the field under consideration is mapped on a rectangular strip. Integration of the equations of motion in the transformed domain is performed by...