August 31, 2023
The Instrument for Lunar Seismic Activity (ILSA) payload on the Chandrayaan 3 Lander is the first instance of a Micro Electro Mechanical Systems (MEMS) technology-based instrument on the moon. It has recorded the vibrations occurring due to the movements of Rover and other payloads.
ILSA comprises a cluster of six high-sensitivity accelerometers, which are indigenously fabricated using the Silicon Micromachining process. The core sensing element consists of a spring-mass system with comb-structured electrodes. External vibrations lead to a deflection of the spring, resulting in a change in capacitance which is converted into voltage.
ILSA's primary objective is to measure ground vibrations generated by natural quakes, impacts, and artificial events. The vibrations recorded during the rover's navigation on August 25, 2023, are depicted in the figure. Additionally, an event, seemingly natural, recorded on August 26, 2023, is also shown. The source of this event is currently under investigation.
The ILSA payload was designed and realised at LEOS, Bangalore, with the support of private industries. The deployment mechanism for placing ILSA on the lunar surface was developed by URSC, Bengaluru.