Attitude estimation for low-cost spacecraft equipped with GPS

The objective of the present paper is to give an overview of spacecraft attitude determination with GPS. GPS receivers with single or multiple antennas nowadays are low-cost sensors that constitute a valuable complement to existing sensor suites. GPS has been widely used for positioning and vehicle navigation. However, using GPS as an attitude...

Linear recursive formulation of flexible multi-body space system dynamics

Numerical simulation of the dynamics of multi-body systems constitutes a central part in the design and analysis of modern space-based systems. The report focuses on the development of a recursive formulation of the dynamics of flexible spacecraft-robotmanipulator systems, suitable for efficient numerical simulation. The rather well-established...

Quasi-recursive dynamics equations for spacecraft-based flexible robotic manipulators

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...

Equivalent flexibility modelling for the recursive simulation of robot manipulator dymamics

The report focuses on the mathematical modelling of the dynamics of spacecraft based manipulators displaying structural flexibility in their links. The equations of motion must be cast in a form suitable for efficient numerical simulation. Equations of motion found in literature are usually written in the form of an augmented system of...

Flexible space-based robot modelling and real-time simulation

The Hermes manipulation system (HERA) is a sophisticated space manipulator system, which has to perform tasks ranging from berthing to tool operation in various operational modes from fully automatic to purely manual. Development and qualification of such a space-based manipulator must be supported by computer simulation facilities. The HERA...

Equivalent flexibility modelling: A novel approach towards recursive simulation of flexible spacecraft-manipulator dynamics

For the simulation of rigid spacecraft manipulator dynamics there exists efficient recursive software. Extension of this software for the simulation of flexible spacecraft-manipulator dynamics would have important advantages. In this paper the method of Equivalent Flexibility Modelling (EFM) is outlined. Each flexible body is re-modelled as a...

On fictitious joints modelling of manipulator link flexibility for the HERA simulation facility pilot

The mathematical model for the dynamics of HERA must take into account structural flexibility in the slender manipulator links. For the HERA Simulation Facility Pilot, the model will contain one bending mode in each bending plane, and one torsion mode. The present document describes how this model can be simulated with rigid body simulation...

Dynamics modelling, simulation, and control of a spacecraft/manipulator system

Four well-known formalisms for mathematical modelling of the dynamics of a spacecraft/manipulator system are derived from the unifying d'Alembert principle. The Newton-Euler formalism is discussed in more detail, as it allows efficient numerical simulation. An algorithm is defined for the control of the manipulator end-effector motion in...

Dynamics of flexible spacecraft: the internal balancing approach towards mathematical model order reduction

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...

Towards digital computer simulation of the dynamics of flexible spacecraft

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...

Application of model following control and estimation techniques to attitude control of manoeuvring spacecraft Part I: Theory and simulation results

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...

Application of model following control and estimation techniques to attitude control of manoeuvring spacecraft Part II: Simulation software description

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...