Spacecraft attitude and orbit control systems testing

Contemporary AOCS are equipped with local Attitude Control Computers which provide sophisticated Attitude and Orbit Control functions, automatic Failure Detection and Isolation functions and extensive Telemetry and Telecommand handling functions. Generic models of the design, development and test life cycle approaches for such Intelligent AOCS...

A new generation test and verification equipment for attitude control systems

Currently a new generation Test and Verification Equipment (TVE) is being developed under ESA contract as successor "to the Test and Simulation Assembly (TSA) for a Modular Attitude Control System (MACS). It will be a modular system that can be tailored for any Attitude and Orbit Control Subsystems (AOCS). The gained experience with complex AOCS...

The MACS-TSA applied in the ISO and SAX spacecraft projects

The place of the Test and Simulation Assembly for a Modular Attitude and Orbit Control Subsystem (MACS-TSA) in the development process of the ISO and SAX spacecraft is given, with emphasis on the simulation aspects. The MACS-TSA is used as checkout equipment during the integration of AOCS, hardware and software at subsystem level. The other...

Design of a standard test and simulation assembly for a modular attitude and orbit control system (MACS): part III: annex 2, design documentation

A Standard test and simulation assembly (TSA) for a modular attitude and orbit control system (MACS) is defined. Its functional requirements, detailed specification and design are presented. The assembly consists of a commercial available minicomputer and a specificly designed front-end which interfaces with the AOCS via an OBDH-, MACS- and IEEE...

Design of a standard test and simulation assembly for a modular attitude and orbit control system (MACS): part II: annex 1, formal specification

A standard test and simulation assembly (TSA) for a modular attitude and orbit control system (MACS) is defined. Its functional requirements, detailed specification and design are presented. The assembly consists of a commercial available minicomputer and a specificly designed front-end which interfaces with the AOCS via an OBDH-, MACS- and IEEE...

Design of a standard test and simulation assembly for a modular attitude and orbit control system (MACS): part IV: annex 3, acceptance testplan

A Standard test and simulation assembly (TSA) for a modular attitude and orbit control system (MACS) is defined. Its functional requirements, detailed specification and design are presented. The assembly consists of a commercial available minicomputer and a specificly designed front-end which interfaces with the AOCS via an OBDH-, MACS- and IEEE...

Design of a standard test and simulation assembly for a modular attitude and orbit control system (MACS): part I: phase 1 study report

A standard test and simulation assembly (TSA) for a modular attitude and orbit control system (MACS) is defined. Its functional requirements, detailed specification and design are presented. The assembly consists of a commercial available minicomputer and a specificly designed front-end which interfaces with the AOCS via an OBDH-, MACS- and IEEE...

The use of ESA starmapper measurements for spacecraft attitude estimation: estimator design rationale and results

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...

Procurement of starmapper software reference run of STRMP5 (Work Package 3)

This memorandum describes and annotates a reference run performed by the STRMP5 computer programme. This attitude determination programme uses a sky model containing intentionally errors. The influence of these errors on the attitude estimate is assessed.

Study of an attitude acquisition measurement technique using the ESA starmapper: Part I: Executive summary

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...

Study of an attitude acquisition measurement technique using the ESA starmapper: Part two: final report

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...

Study of double gimballed momentum wheels in the attitude and orbit control system of a geostationary communication satellite

The potentials of a double glmballed mcwientum wheel as an actuator for the attitude oontrol of a geostationary communication satellite are discussed with respect to the related systems. A justification of the IXaW is given and the characteristics defining the wheel system are determined. They can serve to be the input to a detailed design of an...

Factors influencing the choice of an orbital propulsion system for geostationary satellites

In this report the requirements of orbit control of geostationary communications satellites are investigated. A comparison between chemical and electrical propulsion is made for mission lives up to I5 years. The mass of electrical propulsion is lower than of chemical syetems, even when mass penalties for the low reliability of the ion thrusters...

Stability of double gimballed momentum wheels

Due to the finite stiffness of rotor- and gimbal-suspensions, a double gimballed momentum wheel will oscillate with high natural frequencies. The stability of these oscillations is studied, in order to obtain requirements for the stiffness of the suspensions and/or the gimbal inertia properties. From energy considerations, it is concluded that...

Accuracy of attitude control systems for satellites using double gimballed momentum wheels

Preparatory study of satellite attitude control with momentum wheels

Preparatory study of satellite attitude control with momentum wheels

In this study a survey is given of laimched satellites, paying special attention to mission objectives and attitude control systems. This picture is extrapolated into the near future to analyse the control requirements that are to be expected for future satellite missions. Possible attitude control systems for satellites are also surveyed and...