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Schuler, B. C.

Publications and source records attributed to Schuler, B. C..

Rate-control system /RCS/ for zero-gravity experiments

A sounding rocket payload, free falling in space, with low angular body rates provides a near zero gravity environment. To efficiently utilize the time above the earth's atmosphere, a positive means of controlling angular body rates must be provided for the payload. A rate-control system (RCS) was designed at the Goddard Space Flight Center (GSFC) to meet the requirements of the Space Processing Applications Rocket Program and for use on the Black Brant-V sounding rocket. After the sounding rocket exits the atmosphere, the payload separates, the RCS reduces the initial angular rates to low levels and maintains the low levels until the payload reenters the atmosphere. The maiden flight of the RCS was aboard a NASA sounding rocket. The system performed as expected, and the payload experienced a low-G environment below 0.0001 G for 300 sec. This paper describes the design criteria, the components used, and the mode of operation.

Schuler, B. C.

STRAP IV - High accuracy, low drift attitude control system.

The STRAP IV attitude control system was designed, tested, and successfully launched to provide stable high accuracy pointing at nontrackable X-ray sources. On its initial flight (May 19, 1972), the STRAP IV control system updated its high accuracy, rate integrating gyros on two successive stellar targets and then maneuvered the rocket body to point the experimental payload at two separate X-ray sources and an X-ray-free background location. The third axis, which remained under the control of a coarse free gyro, was updated by a technique of successive star-target coordinate transformation to ensure the correct fine-axis azimuth alignment for the high accuracy inertial maneuvers. Pointing accuracies of 4 arc min with limit cycle stability of less than 20 arc sec peak to peak were obtained on all targets.

Shrewsberry, D. J.