Research progress on torsion pendulum in ground testing of gravitational reference sensor: a review

Space gravitational wave detection has become a hotspot in international cosmological research. The European and American Laser Interferometer Space Antenna space gravitational wave detection program and China's Taiji and Tianqin space gravitational wave detection programs are rapidly developing with simultaneous cooperation and competition. As the core load for space gravitational wave detection, gravitational reference sensors must undergo corresponding ground testing before being launched into orbits. To understand the research progress of ground testing of gravitational reference sensors using a torsion pendulum at home and abroad, this article briefly introduces gravitational reference sensors and their torsion pendulum-based test methods, summarizes the research progress of the use of torsion pendulums at home and abroad, and provides a review of the use of torsion pendulums to test gravitational reference sensors. The development trend of gravitational reference sensors for ground testing is proposed to provide a reference for their development and ground testing for the Taiji space gravitational wave detection program.