Tuesday, January 26, 2010

The Development of Wheels for the Lunar Roving Vehicle

Vivake Asnani, Damon Delap, and Colin Creager
NASA - Glenn Research Center

Abstract - The Lunar Roving Vehicle (LRV) was developed for NASA’s Apollo program so astronauts could cover a greater range on the lunar surface, carry more science instruments, and return more soil and rock samples than by foot. Because of the unique lunar environment, the creation of flexible wheels was the most challenging and time consuming aspect of the LRV development. Wheels developed for previous lunar systems were not sufficient for use with this manned vehicle; therefore, several new designs were created and tested. Based on criteria set by NASA, the choices were narrowed down to two, the wire mesh wheel developed by General Motors (GM), and the hoop spring wheel developed by the Bendix Corporation. Each of these underwent intensive mechanical, material, and terramechanical analyses, and in the end, the wire mesh wheel was chosen for the LRV. Though the wire mesh wheel was determined to be the best choice for its particular application, it may be insufficient towards achieving the objectives of future lunar missions that could require higher tractive capability, increased weight capacity, or extended life. Therefore lessons learned from the original LRV wheel development and suggestions for future Moon wheel projects are offered.

Read the full report (Adobe Reader) HERE.



Soviet Lunokhod (Luna 17, Nov 1970 & Luna 21, Jan 1973). Teleoperated from Earth, 8 traction wheels, 800 kg with a max speed of 2 kph and a range of 37 kilometers.




MET
- (Apollo 14, Feb 1971). Seventy-five kilos on two free wheels, towed by EVA crew with an approximate range of three kilometers.




LRV
- (Apollo 15, July 1971; Apollo 16, April 1972 & Apollo 17, Dec 1972) Operated by astronauts on-board with a joystick, on four traction wheels, a maximum speed of 16 kph, a loaded mass 700 kg and a range 36 kilometers.

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