Some aerospace applications of estimation theory

In this report, the application of estimation theory to three problems from aerospace research is described. The applications considered deal with spacecraft attitude estimation, software reliability modelling and estimation, and with a satellite-based navigation algorithm. Maximum likelihood estimation is used in the software reliability case...

Bayesian estimation for decision-directed stochastic control

Stochastic processes with a decision-directed control are considered as controlled Markov processes, the state space of which is hybrid; i.e. a product of a discrete set and a Euclidean space. This approach yields a mathematical model for many problems of decision-directed stochastic control. In general, the observations made from the "past" and...

Two-dimensional flight-path reconstruction by means of spline approximation

In this report, a method is developed to reconstruct the flight-path of an aircraft in symmetric, non-steady flight by representing this path by a set of splines. That set of splines is chosen, for which the flighttest data are best explained in some weighted least squares sense. This leads to a large, sparse, nonlinear, overdetermined system,...

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...

Survey of modern control and observation theory for disturbed, target following aerospace systems. Part one: Basic theory

The document contains a general theory towards the observation and optimal control of disturbed, target following aerospace systems. Disturbed, target following aerospace systems eire defined as aerospace systems that are designed to track a moving target system, while they are subjected to external, time-varying disturbances. The first five...