Friday, April 13, 2012
Jordin Kare on Recent Laser Propulsion Work
They are proposing a whole bunch of lasers on the ground which beams to a flat plate, heats up the fuel and the rocket exhausts providing push. The current plan is to have one set of lasers to get the vehicle off the ground and a larger batch of lasers to provide the energy as the rocket flies over the main bank of lasers.
Jordin was part of a study on using lasers and/or microwave to power a launch. The group was composed of Myrabo, Kare and Parkin. Each of them has different thoughts and the one group ended up with three different results. Kare’s version had payload of 60kg and a total mass to orbit of 1000kg. He talked about the problem of NASA engineers implementing some of his ideas. Kare was expecting a long thin rocket, the NASA group pushed for more short and fat.
Kare said that there is a commercial product which does what he needs. IPG sells a 10 kW single mode at $130 a Watt, but this is because they have only done small orders. If could order in volume the price would drop to at least to $20 a watt. NASA said his machine should cost about $10,000 a kilogram to build, but most rockets only cost around $2000 to $5000 a kilogram.
I think the study is available here. Be warned, the report is almost 700 pages and takes about 90 Megabytes of space.
The study concluded that this is possible. People asked why. Jordin believes there is a market for putting small amounts of material a thousand times or more a year has value. He walked through some of the economics and technology.
Kare's proposal is to use lasers to basically build an assembly line to launch stuff into space very frequently.