I have created landing gear animations with Blender, baked them, and exported the result to glTF. "Inverse kinematics", "Damped track", and "Child of" constraints where used to ensure that torque link, resistance rod, and piston are animated correctly. Animations affecting multiple objects are merged using NLA track names when exporting to glTF. I didn't find a way to create multiple animations affecting the same objects, so I had to sequence steering, suspension, and gear deployment in the same animation. Wheel rotation however was kept separate. The following screen recording shows Blender playing back the sequence of steering, suspension, and gear deployment in parallel with the wheel rotation. [previewyoutube=A_yCNBr2qdU;full][/previewyoutube] The model including the animations are imported using the Assimp bindings of LWJGL. The suspension and wheel rotation then can be driven using the wheeled vehicle constraint of the Jolt Physics engine. The planet surface was simulated by extracting 3x3 tiles from the planetary cube map and converting them to a static Jolt mesh. By simulating the wheels as moving surfaces, the numerical instabilities of simulating a rotating cylinder with constraints directly are avoided. The result is a beautiful interaction of the landing gear with the ground as shown in the following video (music: "Dune" by Andrewkn). [previewyoutube=GiBjMYRKbfU;full][/previewyoutube] If you are interested in a realistic space flight simulator, please consider wishlisting sfsim on Steam.

At the moment I am developing the landing gear for the spacecraft in the upcoming sfsim simulator.
The Jolt Physics library provides a great physics implementation for wheeled vehicles. Previously I have implemented extracting a small part from the planet mesh and convert it to a Jolt Physics mesh. This then can be used to simulate the behaviour of the suspension and the wheels when the gear makes contact with the ground. [previewyoutube=Dd-tTBWKjTs;full][/previewyoutube] I am also working on an animation for gear deployment. Blender supports different constraints such as inverse kinematics as shown in Mark Alloway's tutorial. Here is a video showing the first working version of the landing gear (doors not implemented yet). [previewyoutube=ckkAMJVVl-U;full][/previewyoutube] Only part left to do is baking animations, exporting it to glTF and driving the animations using information from Jolt Physics. Let me know if you have any comments or suggestions. If you are interested in a realistic space flight simulator, please consider wishlisting sfsim on Steam.