Validation of CubeSat tether deployment system by ground and parabolic flight testing

This paper describes the experimental validation of a CubeSat tether deployment design by air-bearing ground test and microgravity parabolic flight test. The tethered CubeSat mission includes two 1U CubeSats with a tape-type tether of 100 m. The tether will be deployed by pull with two CubeSats separating at a desired velocity. Various ground tests were performed to validate the designed separation velocity, estimate the internal friction force, and measure the deployed tether length. Finally, the engineering model of tether deployment system is validated by microgravity parabolic flight testing. The parabolic flight demonstrated the tether deployment system works as expected. By measuring the separation velocity of CubeSats in the parabolic flight, it reveals the internal friction is much less in the microgravity environment than the value measured on the ground.