January 25, 2024
The 6-meter long magnetometer boom on the Aditya-L1 satellite has been
successfully deployed. It is deployed in the Halo orbit at the Lagrange point
L-1, on January 11, 2024. The boom had been in stowed condition for 132 days
since the Aditya-L1 launch.
The boom carries two state-of-the-art, high-accuracy fluxgate magnetometer
sensors that measure the low intensity interplanetary magnetic field in space.
The sensors are deployed at distances of 3 and 6 meters from the spacecraft
body. Mounting them at these distances minimizes the impact of the spacecraft
generated magnetic field on measurements. , and using two of them assists
precise estimation of this influence.The dual sensor system facilitates
cancelling out the spacecraft's magnetic influence.
The boom segments are constructed from carbon fibre reinforced polymer and serve
as interfaces for the sensor mounting and mechanism elements. The articulated
boom mechanism comprises 5 segments interconnected through spring-driven hinge
mechanisms, allowing for folding and deploying actions. The deployment occurs in
an accordion fashion, controlled by a novel patented Kevlar closed control loop
mechanism, with hinges locking the segments into the deployed configuration.
During the stowed condition, the boom is securely held in position by two
hold-downs, transferring launch loads to the spacecraft body. A thermal
cutter-based release system is employed to execute the boom deployment on
command. Date received through the telemetry switches confirm the hold-down
release, first motion, and locking of all hinges. The observed in-orbit
deployment time was approximately 9 s, well within the predicted range of 8 to
12 s. All telemetry indications for hinge locking and hold-down release were
within nominal parameters.