In 2010, our group (Lunar Robotics) entered the Google XPrize competition. The goal of the competition is to land a small robot on the moon. During the research and preparation for the contest, we made two discoveries that could have a huge potential impact on the future of unmanned space travel.
Our team consists of five engineers - two software engineers, two mechanical engineers, and one rocket engineer (aka, the Rocket Scientist). We each have over ten years experience in our respective fields (some of use have over 20 years).
We have made a few successful launches, in 2010 and earlier in 2011. When we entered the competition, we had a financial backer. Unfortunately, the economy has changed for our backer. We have withdrawn from the competition due to lack of funding.
However, we believe our two discoveries are worthy of pursuit, and could mean that anyone can build their own moon rocket, in their own backyard, for $5,000 or less.
What did we discover? When a rocket is launched from the ground, the rocket must not only fight gravity, but it most also fight air friction. As the rocket gains in altitude, it has less and less air friction to fight against. A large quantity of a rocket's fuel is spent simply fight air friction.
In the 1950's and 1960's, the US Air Force experimented with, and successfully launched rockets from specially designed high altitude balloons. The USAF eventually closed the project, because as the rockets got larger, the balloons would need to many times larger. One successful launch, had a balloon with a diameter of 250 feet!
We quickly realized that unmanned rockets, especially ones carry small cargo payloads, could still be used today. We tested several launches using off-the-shelf high-altitude weather balloons (capable of achieving heights of 100,000 - 150,000 feet).
Our second discovery was the type of rocket fuel used. The majority of modern rockets use liquid fuel. The advantage of liquid fuel is that it compresses (relatively) easily, and has more energy than an equivalent volume of solid fuel.
The disadvantage of liquid fuel is safety and stability. Most types of liquid rocket fuel must be kept below freezing, require high pressure, and the smallest leak or accident could mean a massive explosion. History is rife with liquid rocket fuel accidents.
In the course of our research, we found an off-the-shelf solid state rocket fuel, which provided its own oxidizer. This is important, because space does not contain oxygen, a necessary ingredient for combustion. This fuel has a constant burn rate, is easy to use and transport, requires no special license to use (below a certain volume), and is safe and stable.
Our Goal - The goal of our project is build a rocket capable of reaching the moon, for $5,000 or less. The main expense (approx 75%) for the rocket is the fuel, so a key component of this project is identifying alternative fuel sources or recombinations of existing sources which result in lower cost.
We will be using the latest technologies to assist us in our project. One goal is to create as many parts as possible using 3D printers, laser cutters, and CNC machines. When at all possible, we will off-the-shelf hardware and software, to make this as easy and cost-effective as possible for you to recreate.
- (45 days)