Nearly all mechanism applications require some form of gearbox. Wet lubricated gearbox technologies are limited to the relatively narrow temperature ranges of their lubricants. Dry lubricated gearboxes have proven to be problematic with poor life and reliability characteristics. Testing has shown that dry lubricated rolling elements can be made to work reliably provided they are operated at conservative contact stresses, however when dry film lubrications are tested under the sliding conditions in conventional transmissions they are no longer reliable. During the Phase I SBIR Rocketstar Robotics developed the preliminary design of a transmission that consists of all rolling elements and has eliminated all of the sliding elements that exist in conventional gearing. The transmission operates at contact stress values that are conservative and within the envelope proven through previous testing to provide reliable performance in rolling elements. The resulting transmission can be provided in a range of sizes and offers considerable torque capability within a reasonable envelope while operating within conservative rolling contact stress regimes at operating temperatures from near absolute zero to over 500C. The development and test of a successful prototype could revolutionize the torque transmission industry and open the door to mechanisms operations over a much broader temperature range than is now possible. Rocketstar Robotics proposes that the design be carried through the detailed design phase which includes detailed analysis models and that multiple prototypes be built of two different size transmissions. The units would then be tested for performance and life over the extremes of temperature from near cryogenic to 500C operation. Rocketstar will build 3 small 100 in-lb units and 3 large 400 in-lb units for testing along with spare splines to allow development testing with multiple DFL types. One of each unit will be delivered to NASA.
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Mars. It has long been desirable for robotic vehicles to operate on Mars without requiring heaters during the day as well as at night. Venus. The Rocketstar Cyclo-Therm Drive provides a transmission that could make robotic rovers on Venus a reality. Europa. Beyond earth nowhere in the solar system provide a better candidate for life that Europa. Current technology will have difficulty operating in all the environments that such a probe could encounter. The Moon. With temperatures ranging from -150C to 105C long term lunar exploration of the moon will be difficult for both manned and unmanned missions without technology that can operate over the broad temperatures without the need for heaters or temperature limited operation. Asteroids. Similar to trips to the moon because of a lack of atmosphere, trips to asteroids will face similar extreme temperature hurdles. The temperature on asteroids can vary wildly between the sunlit side and the dark side. Instruments. Frequently even when the environment is relatively benign spacecraft detectors and instruments such as infrared detectors are required to be kept at temperatures close to absolute zero. One example of this would be the mirror focusing actuators on the JWST. Thrust Vectoring. Thrust vectoring is an efficient way of providing space vehicle maneuverability by changing the thrust vector however it can be difficult to implement because the temperature thrusters often operate at.
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