DTUsat logo
Attitude Control System

The Attitude Control System (ACS) determines the satellite orientation in space and may upon request by the OBC alter the orientation.

To do so the ACS has as set of sensors and actuators.

Determination System

The main attitude determination system is a four axis magnetometer. Three magnetometers measures the magnetic field in the X, Y and Z direction and one magnetometer measures the magnetic field diagonal to X, Y and Z axis. This constellation allows for determination of the magnetic field even if one magnetometer fails.

InfraRed sensors are used to determine the satellite attitude with respect to the Earth. This system will be used in conjunction with the deployment of the GGBoom.

A supplement attitude determination system is the MEMS based sun sensor.

Control System

The actuators consist of three magnetotorquers placed perpendicular to each other. When asked to do so DTUsat will be able to alter its orientation by applying a current to one or more of the magnetorquers.

The GGBoom constitutes a passiv attitude control. A long boom (1,3m) is deployed such that it points away from Earth centre. The gravity gradient keeps the satellite oriented such that the boom continously points away from Earth. the passive system needs no power to maintain attitude and will not stop working in case of a set-up in any of the electronic systems.