Free-flight test technique with projectile onboard data recorder for ballistic range has been developing in JAXA Kakuda Space Center. The key technology for the test technique is a JAXA in-housed miniature data recorder, which are small enough to be instrumented in free-flying projectiles. The specification of the recorders are;(1) Sampling rate 100kHz, (2)8-channels for Piezoelectric sensors (or Piezoresistive sensors) (3) Sensitivity 16bit and (4) Duration of 1300ms. The size of a recorder was 58mm diameter × 50mm height including batteries. Preliminary free-flight test results with a capsule shaped projectile flying at transonic speed in open air were performed. The test was conducted in the air driven two-stage light gas gun HEK-G with the newly built 120mm-diameter launch tube. This facility can launch 100mm diameter capsule shaped projectiles, which are going to use to obtain benchmarks of transonic instability to compare with wind tunnel results and with numerical calculations. For measurement of aerodynamic characteristics of the projectile, piezoelectric accelerometers were onboard in the projectile. High-speed video cameras were used for optical measurement of the projectile flying in the air. In the present test campaign with the 120mm diameter launch tube, we successfully conducted to launch and recovered capsule shaped projectile (Japanese reentry capsule HTV-R option 2 configuration), which velocity at the launch tube exit was approximately 220m/s. Acceleration at launch, during free-flight and impacting into the recovery-catcher was recorded with the onboard data recorder.
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