Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA...

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Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA Team ISA operations in cruise RSE support • In-cruise calibration • Periodical checkouts Long-term stability tests ISA “cruise science”

Transcript of Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA...

Page 1: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruise

• RSE support• In-cruise calibration• Periodical checkouts• Long-term stability tests• ISA “cruise science”

• RSE support• In-cruise calibration• Periodical checkouts• Long-term stability tests• ISA “cruise science”

Page 2: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruise

Superior Conjunction Experiment (SCE)

•Quiet dynamical environment (no thrust)•High-precision tracking•ISA on

ISA support of PODISA support of POD

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Page 3: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruise

The direct solar radiation pressure signal is above ISA sensitivity (possibly inside ISA band if MCS is rotating)

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-7 BepiColombo MCS Cruise - 2013 trajectory

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Possibility of instrument calibration by comparison with tracking

Page 4: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruiseRequired information for in-cruise calibration

• Estimation of tracking accuracy during SCEtracking accuracy during SCE, and therefore of the accuracy in recovering the MCS acceleration

• Estimation of the expected acceleration signal acting on the expected acceleration signal acting on the MCSMCS, to be confronted with the tracking accuracy and accelerometer sensitivity

• Re-assessment of expected signals acting on the sensing expected signals acting on the sensing elementselements, taking into account the different positioning of ISA with respect to MCS COM (instead of MPO COM)

• Estimation of tracking accuracy during SCEtracking accuracy during SCE, and therefore of the accuracy in recovering the MCS acceleration

• Estimation of the expected acceleration signal acting on the expected acceleration signal acting on the MCSMCS, to be confronted with the tracking accuracy and accelerometer sensitivity

• Re-assessment of expected signals acting on the sensing expected signals acting on the sensing elementselements, taking into account the different positioning of ISA with respect to MCS COM (instead of MPO COM)

Transducer factor

Page 5: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruise

Periodical checkouts

Long-term stability tests

• Zero position of the sensing massesZero position of the sensing masses: potential drifts in the working positions of the sensing masses will be detectable by a continuous read-out

• Noise levelNoise level: the (nearly constant) solar radiation pressure and the residual vibrations on MCS being the only source of vibration noise, it will be possible to test the instrument intrinsic noise with high accuracy

Page 6: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruise

“Cruise science”

• Direct measurement of solar radiation pressure• Flybys (“anomalies”, gradiometric measurements)• Direct measurement of solar radiation pressure• Flybys (“anomalies”, gradiometric measurements)

An accelerometer disentangles gravitational and non-gravitational effects

Out of the spacecraft center of mass, an accelerometer measures also gravity gradients

Page 7: Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario ISA TeamISA Progress MeetingRome, 26 May 2009 ISA operations in cruise.

Istituto Nazionale Di Astrofisica - Istituto di Fisica dello Spazio Interplanetario

ISA Team ISA Progress Meeting Rome, 26 May 2009

ISA operations in cruise

RSE-RD 50 ASD TN 35 page 11

ISA operation requirements for SCE