An Open Source contender for Moon 2.0

Team FREDNET is the name of the Google Lunar X Prize‘s only self-proclaimed ‘open source’ contestant, led by Fred J. Bourgeois, who also raised the initial $10,000 entrant fee for enrolling the team in Google’s contest. Everything from system specifications to the operational source code of Team FREDNET’s lunar transfer and rover systems will be posted on the project’s web site for the world to see, and significant portions of the mission development is being conducted through the project’s online forum where anyone can contribute their own ideas and suggestions. Using this open format, Bourgeois hope that many different design proposals will come forward for the project leads to consider in their quest to deploy a robotic rover on the face of the Moon.

Team FREDNET outlined their first basic mission plan in late July. According to the draft plan, FREDNET will rely on commercial launch providers to lift their spacecraft into orbit around the Earth, and then, if the chosen launch vehicle does not support so-called Trans Lunar injection, establish communications with the space craft from ground stations and direct propulsion systems aboard the spacecraft itself to send the craft onwards to the Moon and into lunar orbit.

In lunar orbit, the lander module (named the Lunar Lander) will detach from the rest of the spacecraft (named the Lunar Bus). Once in its own orbit, the lander will  scan the lunar surface with a laser range-finder (LRF) for one of the four retroreflector mirrors left by earlier missions to the Moon (e.g. Apollo), and, once located, ingenuously use the reflector as a waypoint as the lander initiates descent towards the surface.

Projected trajectory of Team FREDNET's spacecraft.

During descent, the lander will keep calibrating its trajectory relative to the retroreflector on the surface and gradually decrease its velocity using on-board thrusters. Vertical altitude and velocity is determined using the LRF, horizontal velocity using cameras and a feature-point detection algoritm, calculating how fast a, say, crater is drifting away on the recorded footage as the lander approaches the surface.

At an altitude of about 30 meters, the lander will profile the landing site with a laser to find a suitable landing spot. At an altitude of less than 1 meter, the lander’s trusters will cut off, to minimize dust accumulation around the landing spacecraft. The lander will then free fall for one second to finally hit the lunar surface at an velocity of about 1.6 m/s. This small amount of momentum will be transferred to impact absorbers on the legs or body of the lander, and the g-force generated will initiate the antenna and rover deployment system.

Once on the surface of the Moon, a number of operations, some of which are driven by contest requirements, are planned for the rover, including recording video as it travels the lunar regolith and sending the world’s first e-mail from the surface of the Moon to ground stations on Earth.

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