maybe make it like a hamster ball.
edit: just realized my own stupidity, a ball would be very hard to land..
edit: just realized my own stupidity, a ball would be very hard to land..
https://en.wikipedia.org/wiki/Mars_Exploration_Rover#Airbags
See also the section "uprighting", further down the page - they used a tetrahedral shell with a sensor so it knew which side was down and could lever itself upright.