Sherpa OTV Passes Vibration Testing
Spaceflight completed vibration testing on its latest generation Sherpa OTV, Sherpa LTC. Testing has been conducted on the primary Sherpa structure, the Configurable Annex Base (CAB), putting it through environmental testing to clear its use for flight on SpaceX’s Transporter-3 no earlier than January 2022. The completion of this testing clears the Sherpa OTV to start customer integration and the final configuration for flight.
We’re breaking new ground at Spaceflight through applying a standardized test campaign on all Sherpa vehicles to verify launch environmental compatibility and fully characterize load transfer through our vehicle to customer payload interfaces."
Adam Hadaller, Chief Engineer at Spaceflight.
The ride to space is not a benign environment, and preparatory testing is a must. We do this to ensure not only that Sherpa will survive — and thrive, but there are no failures that can impact the customers’ spacecraft or the launch vehicle provider. That’s why Sherpa is subjected to an environment and load testing regimen that is more severe than it would see in flight, according to the company
The testing was completed at NTS facility in Santa Clarita and included acceptance vibration testing for the Sherpa-FX3 and LTC1 CAB. This testing included:
Perform Sherpa-FX3 Vibration Acceptance Testing (y-axis)
Pre-test baseline sine sweep to characterize the structure
Quasi Static Sine Burst test, Sine Vibration test, Random Vibration test
Complete testing on FX3 unit in the second horizontal axis
Reconfigure shaker table to test vertical axis
Complete FX3 Testing in the vertical axis
Swap out the FX3 unit for the LTC1 test unit
Instrument Sherpa-LTC1 test unit. Same 10 triaxial accelerometer setup as FX3.
Begin Testing on LTC1 Vehicle. Rinse & Repeat.
Complete Sherpa-LTC1 vibration acceptance testing in all axis
Data review and procedure closeout for both test units
Basic vibration engineering shows that the loads experienced by customers will not be exactly that of the launch vehicle. So this is not only a validation of those customer loads, but also an opportunity to refine analysis techniques for the next mission.
"We’re breaking new ground at Spaceflight through applying a standardized test campaign on all Sherpa vehicles to verify launch environmental compatibility and fully characterize load transfer through our vehicle to customer payload interfaces," said Adam Hadaller, Chief Engineer at Spaceflight. "Our test approach proves vehicle robustness while developing environmental loading for our customers’ spacecraft to ensure the highest level of mission assurance.”
(Image provided with Spaceflight news release)