High accuracy microaccelerometer is a device that enables you to measure an influence of non-gravitational forces upon an artificial satellite. It is used for measurement of very small and slow accelerations in space. The principal part of electrostatic accelerometer for space applications is a sensor based on a free-floating proofmass placed within a cavity of the same shape. To measure and control the proofmasss actual position inside the cavity, position detectors are used. They are working on the principle of capacity measurement between the proofmass and electrodes. The proofmass is kept at the center of the cavity by six independent electrostatic servomechanisms applying an action control voltage to electrode pairs. Electrostatic forces needed to fulfill this task are directly proportional to the forces acting on the satellite body.
- The principle of microaccelerometer was successfully verified on the Russian satellite Resurs F1 in 1992.
- The improved version was tested on the shuttle Atlantis during the flight No. STS-79 in 1996.
- The next version of microaccelerometer was tested during the flight of the 6th Czech national satellite MIMOSA in 2003.
- To reach better performances the new version of microaccelerometer was developed and verified on Russian satellite TATIANA 2 (launcher SOJUZ) in 2009.
- The latest version of microaccelerometer has been prepared for the SWARM mission from Earth Observation program supported by ESA with EADS Astrium as the prime contractor. The launch is scheduled to be in 2013.
- Measuring range – rotational +9.6e-3 rads-2
- Measuring range – linear 2.1e-4 ms-2
- Resolution – rotational 4.09e-7 rads-2
- Resolution – linear 8.94e-9 ms-2
- Frequency range from 1e-4 to 1e-1 Hz
- Accuracy of acceleration measurement 0.2 %
- Measurement is 24bit with 20bit significant
- Long term stability in linear channels 1e-8 ms-2/day
- Supply voltage 28 V
- Average consumption 6.5 W
- Command and Data Communication RS422 full duplex interface
- Redundancy Communication and supply interface only
- Operating temperature range from -10 to +50 C
- Non-operating temperature range from -40 to +60 C
- Mechanical loads Random 15.23 gRMS
- Mechanical loads Shock 750 gSRS@4kHz
- Dimensions 345 x 204 x 177 mm
- Weight 6.4 kg