Unity 3D: Space Physics Experiments 03 - Landing Gear Prototyping
Not necessarily space, but something I've always wanted to try nonetheless: animated suspension on landing gear.
My goal was to use baked in animations to create collapsible landing gear suspension. I finally got around to learning how to set up basic IK rigs in 3DS, and exported that animation into Unity.
For some reason I was convinced that Unity had built in support for doing something like this. Unfortunately it doesn't even have an easy way to tell how far up the suspension a wheel collider has moved. In the end, I figured out that you can deduce that number from finding the distance between the wheel's location and the location of its transform. Those two are not the same thing for a wheel collider. From there, it's just a matter of carefully lining up and setting up the wheel spring parameters to match the strut animation, and then calling a specific frame based on where the wheel is in the suspension.
I'm really happy with how this turned out. I was very worried I might have to do some really wacky faked IK stuff in Unity that would have just been terrible because it would be unique to every single set of landing gear. With animations, all the motion is handled through simply calling an animation.