Searched for: subject%3A%22spacecraft%22
(61 - 80 of 89)

Pages

document
Delil, A.A.M. (author), Heemskerk, J.F. (author)
Two mechanically pumped two-phase test rigs were built at NLR in order to experimentally study critical issues of spacecraft two-phase thermal management systems: - a 5 kW, 31 mm ID, freon loop, focusing on the critical components of the ESA Two-Phase Heat Transport System. - a 30000 W, 4.93 mm ID, ammonia loop, to support the development of the...
report 1990
document
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
Wanhill, R.J.H. (author)
The opportunities for sustained load fracture control in spacecraft are indicated. Emphasis is given to verification by small-scale laboratory testing.
report 1989
document
Veldman, A.E.P. (author)
Time-integration methods for partitioned dynamical systems and iterative methods for viscous-inviscid interaction are unified using the language of linear algebra. In this way all expertise built up in viscous-inviscid interaction methods becomes available for the integration of partitioned dynamical systems. This report applies some well...
report 1989
document
Delil, A.A.M. (author), Heemskerk, J.F. (author)
The monitoring of the quality of the two-phase mixture at various locations in the system is a valuable, possibly indispensable, part of the control system needed to properly operate a two-phase heat transport system for large spacecraft. Based on a trade-off of various quality monitoring concepts, NLR started to develop a dedicated quality...
report 1988
document
van Woerkom, P.T.L.M. (author)
The objective of the study is to develop the equations of motion of a single link, flexible manipulator, attached to an orbiting spacecraft. A payload may be attached to the end-effector of the manipulator. Starting point is d'Alembert's principle, with displacements described by hybrid coordinates. The equations of motion for the two-body...
report 1988
document
van Woerkom, P.T.L.M. (author)
The objective of the study is to contribute towards the formulation of a mathematical truth model for the dynamics of a robotic manipulator which is attached to an orbiting spacecraft-manipulator system consisting of rigid constituent body is assumed to be known; here the generalization to the case of structurally flexible bodies is attempted....
report 1987
document
Delil, A.A.M. (author)
Two-phase flow heat transport systems for the Columbus Space Platform and the Space Station are expected to incorporate systems to control the liquid flow rates into evaporative cold plates. Candidate components for such a control system are sensors monitoring the (very high) mixture quality at the cold plate exit lines, control algorithms and...
report 1987
document
Delil, A.A.M. (author)
Different concepts for a moveable thermal joint are described and discussed with respect to the applicability in a dedicated deployable or steerable heat pipe radiator system to handle the waste heat of the NiH batteries of the Polar Platform. Concepts which are identified as possible candidates for near-term deployable radiator development are:...
report 1986
document
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
document
Milgram, P. (author)
This report presents a discussion of short-term human engineering research requirements for developing rendezvous and docking and space telemanipulation capabilities. A catalogue of research topics related to human-in-the-loop teleoperation performance is given. This is followed by an overview of available resources for model analytical...
report 1985
document
Milgram, P. (author)
This volume comprises the executive summary of the final report of the study on Control Loops with Human Operators in Space Operations, performed for the European Space Agency (ESA). It summarises the following four volumes: Part I : Human Engineering Analysis, Synthesis and Evaluation Techniques (NLR) Part II : Robotics Operations and Manual...
report 1985
document
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
document
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
document
Prins, J.J.M. (author)
The testing of Spacecraft Attitude and Orbit Control Subsystems is described from the early design up to in-flight, inclusive. Main topics dealt with are: description of three generic AOCS test classes, model philosophy, standardization, subsystem static test methods, subsystem dynamic test methods, generic test equipment and test facilities....
report 1984
document
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
document
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
document
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
document
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
document
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
Searched for: subject%3A%22spacecraft%22
(61 - 80 of 89)

Pages