cr0sh:
Prodigy_Snipes:
-tell when it hits the surface from the job and drive out of a capsuleWell - first you need to know when the capsule is no longer in motion, and you also need to know that the capsule is "upright" (how are you going to ensure this? Even with a parachute, you might not land upright!). Probably a 3-axis accelerometer would be best for this, that way you can measure if you are still in motion, also when you "hit" the surface (a large jolt in acceleration opposite - I believe? - to "down"). You might also want something on the capsule that can tell when surface contact has been made (maybe a simple switch?). Or - if acceleration measurement is too much, look for a "caged ball" sensor to determine "orientation". Using one of those, and some kind of contact sensor switch on the capsule, might be enough to tell you "I am down, and I am upright - open pod bay doors, HAL"...
The landing capsule could be designed like the ones used on NASA's Pathfinder and Mars Exploration Rovers. They were tetrahedral in shape, with "pedals" that could shift the base (where the rover was attached) to be on a flat surface even if it didn't land completely right-side-up.