<story><title>Write code, fix the space station, win $10,000</title><url>http://hackaday.com/2013/01/19/write-code-fix-the-space-station-win-10000/</url></story><parent_chain></parent_chain><comment><author>progn</author><text>Optimization problems like that are fascinating. We can treat them generically without having to teach our program about the specific problem it&apos;s trying to solve. All we have to do is come up with proposed solutions and pare them down.&lt;p&gt;For starters, we need a &quot;cost function&quot; so we can see which solutions are better than others. That&apos;s the easy part: render the model on 3D hardware, lighting it with a distant point light source. The &quot;cost&quot; (the value we&apos;re trying to minimize) is 1 - Σ(face_brightness); modern hardware can easily handle precise geometric shadowing using a stencil buffer or similar well-known technique. Handle the thermal constraints by setting the &quot;cost&quot; to 1 when the space station disintegrates.&lt;p&gt;Now we just need to find some ways of coming up with proposed solutions and pruning all but the best solutions. This problem has path dependencies, so we can&apos;t just apply a greedy algorithm. That is, solar panel actuators take time to move, so the best solution for time [T_1, T_3] isn&apos;t necessarily the concatenations of the best individual solutions for intervals [T_1, T_2] and [T2, T_3].&lt;p&gt;What you&apos;re left with is actually a graph search problem, where our graph nodes are actuator inputs at specific (quantized) times; I feel like something like the veneralbe A* algorihm would be a good place to start looking for paths through this graph.</text></comment>
<story><title>Write code, fix the space station, win $10,000</title><url>http://hackaday.com/2013/01/19/write-code-fix-the-space-station-win-10000/</url></story><parent_chain></parent_chain><comment><author>jtchang</author><text>So many trash comments on the site about how NASA should be &quot;offering more money&quot; or how this is a way for them to &quot;save money&quot; and it is all a scam.&lt;p&gt;Seriously? Any decent hacker attempting this is probably doing it for props. The money is great and provides a good monetary incentive but when it comes down to it I&apos;d wager people would do this for free. Hell a personal tour of NASA and maybe their name in the code might but just as good.</text></comment>