6 December 2001Rosetta SOWG 1/10

Status of the RosettaProject TestBed (PTB)

P. van der PlasModelling and Simulation Section

ESA/ESTEC

ESA/Estec6 December 2001

6 December 2001Rosetta SOWG 2/10

Rosetta Project TestBed (PTB)• Simulator supporting Rosetta Science Operations• Real-time simulation core with variety of models• Capable of generating S/C trajectory and attitude• Capable of importing S/C trajectory and attitude• Capable of generating input data for the EPS• Capable of simulating experiment operations• Extensive visualisation capabilities (3D, maps)

6 December 2001Rosetta SOWG 3/10

The Rosetta mission• January 2003 Launch• August 2005 Mars fly-by• November 2005 Earth fly-by #1• June 2006 Otawara fly-by• November 2007 Earth fly-by #2• July 2008 Siwa fly-by• March 2011 Wirtanen arrival

6 December 2001Rosetta SOWG 4/10

Complete Mission Scenario

6 December 2001Rosetta SOWG 5/10

Earth Escape Scenario

6 December 2001Rosetta SOWG 6/10

Mars Fly-by Scenario

6 December 2001Rosetta SOWG 7/10

Asteroid Fly-by Scenarios

6 December 2001Rosetta SOWG 8/10

Comet Scenario

6 December 2001Rosetta SOWG 9/10

Current PTB Status• Earth (and Moon), Mars (and Phobos/Deimos),

Siwa, Otawara and Wirtanen models available• All mission phases implemented• Star catalogue (up to 100,000 stars) including

constellations for experiment FOV analysis• EPS software v0.5 integrated (event generation,

simulation of experiment operations)• Pointing Request (PTR) execution completed

6 December 2001Rosetta SOWG 10/10

PTR Execution• Goal:

– To support analysis of pointing opportunities and to assess feasibility of pointing timelines

– To reduce the iteration time between the RSOC and the FD team in constructing pointing timelines in combination with the experiment operations

• Interface: The Pointing Request (PTR) file format

6 December 2001Rosetta SOWG 11/10

PTR File Format• PTR modes: INERT, NADIR, TRACK and LIMB• Time based or event based• Predefined database of celestial objects, landmarks

on target bodies (e.g. the Moon, Wirtanen)• PTB will perform various levels of error checking

– Goal: To produce a feasible pointing request timeline that can be processed in detail by the FD team

• Execution including simple slew computations

6 December 2001Rosetta SOWG 12/10

PTR File ExampleRef_date: 27-August-2005_05:01:40

Start_time: 00:00:00End_time: 1_00:00:00

# Pointing slot 00_00:00:00 RSOC INERT ( \ SLEW_POLICY = BEFORE_NEXT \ DURATION = 1000.0 [seconds] \ OBJECT = Polaris)

# Pointing slot 10_00:35:00 RSOC TRACK ( \ SLEW_POLICY = IMMEDIATE \ DURATION = 600 [seconds] \

REF_BODY = Phobos \ OBJECT = PhobosLM1)

# Pointing slot 20_00:51:40 RSOC NADIR ( \ SLEW_POLICY = SMOOTH \ DURATION = 400 [seconds] \ POSITION_ANGLE = 90.0 [degrees] \ OFFSET_ANGLE = 5.0 [degrees] \ FRAME = EME)

6 December 2001Rosetta SOWG 13/10

Future PTB Improvements• Improving the comet model, supporting irregular

shaped bodies• Extending the 3D visualisation, e.g. displaying

sequences of images in 3D• Integrating new EPS versions, displaying

experiment information in real-time (modes, states), adding events to be generated

• Etc, etc…