Trigger Mechanism for Obtaining Dynamic Derivatives in Wind Tunnels Using Free-Oscillation Technique

What is it about?

After completing a space-mission, astronauts need to be safely brought back to the earth in crew-modules. For this purpose, deployment of deceleration systems / subsystems is essential. To enable the same, proper understanding of the dynamic response of the crew module at various wind speeds has to be established through dynamic tests in wind tunnels. Free oscillation tests are best suited for such tests. During the tests, a trigger mechanism is required to initially hold the motion of the model at an initial position and instantaneously release the hold to permit model to oscillate on a spring. In the present paper, the performance of a pneumatic and a mechanical trigger mechanism in bench tests as well as in wind-on tests are compared. It is established that the mechanical trigger meets all the requirements.

Featured Image