A triboelectric nanogenerator sensor-based capture, positioning and release mechanism (CPRM) for test mass in TianQin Gravitational Wave detection Project

Space-based gravitational wave (GW) detection offers a powerful platform for observing millihertz GW signals and probing extreme astrophysical phenomena. As an important part for GW detection, monitoring key state during test-mass (TM) capture, positioning, and release is essential. Here, we designed a capture, positioning, and release mechanism (CPRM) for TianQin project, and further constructed a monitoring system based on triboelectric nanogenerator (TENG) to achieve state recognition of TM during the three-stage process. Three nano-TENG sensors generate characteristic pulse signals (>0.5 V, >0.8 V, >2.5 V, respectively). Varied timing sequences and peak magnitudes of the signals characterize the mechanical motions of the CPRM, allowing effective feedback and state recognition throughout the multistage capture, positioning and release (CPR) process. This work provides a promising strategy for monitoring the TM states during the CPR process and broadens the application of TENGs in high-precision aerospace systems.