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van Woerkom, P.T.L.M. (author)The sttdy aims at a synthesis of the large body of literattire dealing with the analytical description of the perturbed motion of rigid, spinning spacecraft. The reader is familiarized with the various mathematical approaches to the problem. The class of restricted, perturbed motion is analyzed using the Poincarê asjrmptotic expansion procedxire...report 1972
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- Traas, C.R. (author), van Woerkom, P.T.L.M. (author) report 1972
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Boerstoel, J.W. (author), Huizing, G.H. (author), van Woerkom, P.T.L.M. (author)Purpose of the present study is the investigation of the validity of a new algorithm for the estimation of parameters related to spacecraft torques. The algorithm is based on data reduction by numerical differentiation using smoothing splines. Measured data of the ESRO lA "Aurorae" spacecraft are used. It is concluded that the new data reduction...report 1974
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van Woerkom, P.T.L.M. (author)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...report 1976
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- van Woerkom, P.T.L.M. (author) report 1976
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van Woerkom, P.T.L.M. (author)The attitude motion of interplanetary, spinning spacecraft under the influence of solar radiation and optimal thrusting, is investigated. A general model is formulated to describe the forces and torques exerted on the spacecraft due to solar radiation. The model is compared with model! available in the large body of literature on the subject. It...report 1978
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van Woerkom, P.T.L.M. (author)This document extends the general theory of observation and control for disturbed, target following aerospace systems surveyed in the companion document NLR TR 76041 U, to include stochastic disturbances. The theory thus extended is then applied to the high accuracy attitude control of a one—dimensionally rotating spacecraft, equipped with a...report 1978
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van Woerkom, P.T.L.M. (author), Traas, C.R. (author)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...report 1978
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van Woerkom, P.Th.L.M. (author), Sonnenschein, F.J. (author)The study deals with the rotational motion of a spin-stabilized spacecraft equipped with a V-slit sun sensor and the X-slit ESA starmapper. Assuming complete absence of an a priori attitude estimate, it is required to produce a rough estimate of the spacecraft attitude motion. It was assumed that sensor misalignments, external torques and...report 1979
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van Woerkom, P.Th.L.M. (author), Sonnenschein, F.J. (author)The study deals with the rotational motion of a spin-stabilized spacecraft equipped with a V-slit sun sensor and the X-slit ESA starmapper. Assuming complete absence of an a priori attitude estimate, it is required to produce a rough estimate of the spacecraft attitude motion. It was assumed that sensor misalignments, external torques and...report 1979
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- van Woerkom, K. (author) report 1981
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van Woerkom, P.T.L.M. (author), Sonnenschein, F.J. (author), Moek, G. (author)In order to obtain highly accurate estimates of the attitude motion of spin-stabilized spacecraft one may decide to use a starmapper as basic attitude sensor. This reliable and versatile sensor detects the times of crossing of stars over photosensitive slits. Suitable data processing techniques are needed to transform the highly accurate...report 1981
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van Woerkom, P.T.L.M. (author)The report deals with the equations of motion of spacecraft with rigid main body, flexible appendages, and rotors and jets on the main body. The hybrid coordinate modelling method is applied. The resulting equations describe the translational motion of the spacecraft, the rotational motion, and the coupling between these two types of motion. The...report 1981
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Zwartbol, T. (author), van den Dam, R.F. (author), Terpstra, A.P. (author), van Woerkom, P.T.L.M. (author)The paper presents an approach to sampled data, on-board estimation and control of the attitude motion of manoeuvring spacecraft. Algorithms for (1) estimation of gyroscope parameters (drift rate bias, scale factor error) and spacecraft state (attitude, angular velocity, disturbance torque), and (2) model following control of attitude manoeuvres...report 1982
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Zwartbol, T. (author), Terpstra, A.P. (author), van Woerkom, P.T.L.M. (author), van den Dam, R.F. (author)This document presents an approach to sampled data, on-board estimation and control of the attitude motion of manoeuvring spacecraft. Algorithms which are developed include: a - model following control of attitude manoeuvres b - estimation of spacecraft state (attitude, angular velocity, disturbance torque) c - optical-inertial attitude...report 1982
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Terpstra, A.P. (author), van den Dam, R.F. (author), van Woerkom, P.T.L.M. (author), Zwartbol, T. (author)This document describes two computer programs developed during a study of the application of modern control techniques in the area of spacecraft attitude control. Theory and simulation results are described in part I of this report. In part II a general overview of the tasks of the simulation program is presented, and program design aspects are...report 1982
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van Woerkom, P.T.L.M. (author)Software design for digital computer simulation of the dynamics of flexible spacecraft equipped with actuators and sensors, should take into account two properties of the overall system: (i) s.ampled-data control of the spacecraft leads to discontinuous inputs (forcing functions) in the differential equations of motion, thereby requiring...report 1983
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Milgram, P. (author), van Woerkom, P.T.L.M. (author), Wewerinke, P.H. (author)This report presents the results of an illustrative analysis of human-in-the-loop rendezvous and docking (RVD) performance, for the purpose of demonstrating the practicality of applying human engineering methods and techniques, introduced in Part I of this project, to the analysis of control loops with human operators in space operations....report 1984
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van Woerkom, P.T.L.M. (author)Increases in size and mechanical complexity of spacecraft result in increased complexity of the mathematical model which describes the spacecraft dynamics. This results in turn in increased computational effort, in increased difficulties in understanding the characteristics of the spacecraft dynamics, and in increased difficulties in the design...report 1985
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van Woerkom, P.T.L.M. (author)Mathematical models of the dynamics of spacecraft are needed to carry out numerical simulations, to gain insight into the characteristics of the spacecraft dynamics, and to synthesize control algorithms suitable for online system Identification, estimation, and control. Increases in size and mechanical complexity of spacecraft result in...report 1985