Safety Design for Space Operations

• Thrust level and thrust direction errors:These errors can be reduced by particular calibration maneuvers at the beginning of the mission.

• Thrust duration errors:Duration of thrust depends on the thrust level available and on the boost to be achieved. Errors can be kept very low, when controlled by the clock of the onboard system.

• Start time errors:Start time of thrusts can be calculated either on board or on ground. In particular the start time of the second boost has to be determined accurately together with the thrust duration to end the trajectory at the desired point. When calculated on ground, time tagged commands will be sent to the spacecraft and executed according to the onboard clock. In both cases time errors can be kept ...