Process and system for discharging a test mass free-floating in a satellite

A computer program product encoded with machine-readable program commands for a control unit of a data processor which cause the latter to implement a process for discharging a test mass that is free-floating inside a surrounding electrode casing on board a satellite, the electrode casing having at least one first electrode for applying electrostatic forces or moments to the test mass and for the electrostatic measurement of the position or orientation of the test mass;

• at least one second electrode for modulating, particularly high-frequency, alternating voltages for measuring purposes on the test mass;
• at least one light-emitting element, which irradiates at least one of the test mass, the electrode casing, and the electrodes with ultraviolet light, to generate a photoelectric effect;
• said processing comprising automatically and iteratively:
• determining a test mass charge of the test mass;
• and
• performing a control operation to eliminate the determined test mass charge, until the test mass charge has reached a defined target value.

A system for discharging a test mass that is free-floating inside a surrounding electrode casing on board a satellite, the electrode casing enclosed by a vacuum tank having:

• at least one first electrode for applying at least one of electrostatic forces and/or moments to the test mass;
• at least one second electrode for modulating, particularly high-frequency, alternating voltages for measuring purposes onto the test mass;
• and
• at least one light-emitting element, which irradiates at least one of the test mass, the electrode casing, and the electrodes with ultraviolet light for generating a photoelectric effect;
• wherein the system has devices for the implementation of a process for discharging a test mass that is free-floating inside a surrounding electrode casing on board a satellite, the electrode casing having at least one first electrode for applying electrostatic forces or moments to the test mass and for the electrostatic measurement of the position or orientation of the test mass;
• at least one second electrode for modulating, particularly high-frequency, alternating voltages for measuring purposes on the test mass;
• at least one light-emitting element, which irradiates at lest one of the test mass, the electrode casing, and the electrodes with ultraviolet light, to generate a photoelectric effect;
• said processing comprising automatically and iteratively:
• determining a test mass charge of the test mass;
• and
• performing a control operation to eliminate the determined test mass charge, until the test mass charge has reached a defined target value.