We dropped our Spacecraft
No really, we’re not kidding.
If you have been following what we’re up to, you’d know we recently went live with the drop test of our landing gear.
We had conducted a vibration and drop test of the lander structure prototype at NAL in Dec 2014. This played a critical role in securing independent technology validation by the GLXP experts, winning us $1 million as the Milestone prize for our lander technology.
Why the drop test?
A smooth and stable touchdown of a spacecraft moving with vertical and horizontal velocities on the lunar terrain is a must for a successful mission. To achieve this, landing gear with specially designed impact-energy absorbent (crushable aluminium honeycomb) is incorporated in the spacecraft.
The landing gear design with the absorbent and several other features require experimental validation well before implementation on the lander spacecraft.
The drop test setup
On 7th July 2017, we conducted the qualification test of our landing gear design with a full-scale drop test at our facility.
A flight-type landing gear system was dropped from a height on to a simulated lunar terrain to replicate the impact expected during an actual moon landing. The spacecraft velocities at impact were simulated by fixing the drop height.
And we go live with the drop test.
1. Crush of honeycomb in landing gear = ~40 mm
2. Compaction/sinkage of the simulated lunar terrain = ~15–20 mm
3. Peak instantaneous acceleration at base of landing gear = ~17 g
All the results including the high-speed videography all show excellent performance. The foot pad restraining mechanism which was designed to break on touchdown, functioned as intended.
“Completion of a few more tests and a closer study of results will help us fine-tune the landing gear hardware and assemble it on the spacecraft qualification model for conducting the full set of qualification tests to get ready for launch,” says structures lead Dr P.S. Nair.
Next on our to-do list is drop tests with varying horizontal and vertical velocities. We will also be looking at experimenting with different inclinations of the terrain while performing these tests.
This is a special article where our scientists and engineers share their take on the technology driving our mission. This article is by TeamIndus Jedi commander Dr. P.S Nair.