High Payload Capacity

HABE (High Altitude Balloon Experiment)

Developed for the Ballistic Missile Defense Organization (now the Missile Defense Agency), the HABE gimbals use the Roto-Lok® rotary drive to point balloon borne telescopes that track missiles from launch until their propulsion engines are expended. Roto-Lok® drives are used to position the 1,700 pound laser and telescope payload hanging under a 17 foot tall 6,500 pound gondola. The Roto-Lok® drives were chosen because no other technology could provide the needed accuracy and response within the weight and power budget for a balloon operating at 85,000 feet.

The azimuth drive is a dual-drive system with a belt driven coarse drive, capable of continuous revolution, to derotate the payload with respect to the freely turning balloon so that the Roto-Lok® driven fine drive with 320° of total travel can be held centered on the target during acquisition and tracking. The elevation drive provides +90° to -90° angular range for acquisition and tracking.

The drives use a brushless DC servomotor/gearbox first stage with a 2:1 ratio driving a 36:1 Roto-Lok® second stage, for a total end-to-end ratio of 72:1. Both axes are equipped with absolute encoders with a positional resolution under 10 microradians.

The HABE drive systems are designed for operating temperatures of+40°C to -50°C and for an altitude of 85,000 ft. In addition, the bearings and structures are designed to survive, without damage, an 8g shock load upon parachute opening and a maximum 10g load upon landing.

(Photos courtesy of the Missile Defense Agency)