In a study published in Sensors, a research group led by Prof. WANG Zhi from the Changchun Institute of Optics, Fine Mechanics and Physics of the Chinese Academy of Sciences,studied advance charge measurement method enhances space sensor accuracy.

In the quest for more precise space missions, especially those involving gravitational wave detection, the reliability of inertial sensors is paramount. These sensors, central to missions like LISA (Laser Interferometer Space Antenna) and Tianqin, require the inertial mass to remain undisturbed, floating freely within the spacecraft. This setting is critical to avoid interference from both the satellite platform and extraterrestrial influences.

Typically, inertial masses accumulate charges due to cosmic rays and solar particles, which then interact with surrounding magnetic fields and conductors. This interaction can generate forces that disturb the mass, leading to measurement inaccuracies. Existing methods, such as force modulation, have been utilized to estimate these charges but come with significant limitations. These methods, while effective, risk interrupting the primary mission objectives, such as gravitational wave detection, due to their intrusive nature.

Researchers have now developed a new high-precision charge measurement method using phase-sensitive demodulation (PSD). This technique allows for a more accurate assessment of the charges by employing a torsion pendulum to simulate conditions in space. The pendulum, by its design, offers a unique degree of rotational freedom that mimics the free-floating conditions of the test mass in orbit.

The application of PSD in charge measurement significantly outperforms traditional methods like the Butterworth band-pass filtering technique. Simulation results indicate that PSD not only offers higher accuracy but also features enhanced resistance to external interference, a crucial advantage in the fluctuating conditions of space.

The advancement in charge measurement techniques marks a significant milestone in space exploration technology. By ensuring higher accuracy in inertial sensor readings, missions can achieve more precise data, essential for projects like LISA and Tianqin. This improvement could potentially lead to better management of the charges on inertial masses, thus enhancing the overall reliability and success of future gravitational wave detection missions.

The development of the phase-sensitive demodulation method for charge measurement in inertial sensors signifies a leap forward in space technology. With its proven higher precision and robustness against disturbances, this method is set to enhance the performance of sensors critical to the success of next-generation space missions. As space exploration continues to advance, the integration of such refined technologies will be crucial in overcoming the physical challenges of the cosmos.