An idea that I think is pretty ingenious and would be a shame not to use - borrow this mechanic from RC Airplane landing gears:
In this video, the landing gear doors are opened by the spring trying to straighten itself. As the gear comes up, the compartment opens up. As the gear goes back in, the doors close around it. All of that is driven by the movement of the landing gear, no extra servos needed.
A similar design could be used for the arms and part of the legs (
maybe fingers too). I'm envisioning a rectangular piece on the top of the arm (where a watch would rest) that acts as the "skeleton" of the suit, which is connected with hinges to two curved doors, one to go around each side of the arm. These curved doors would connect to each other with a simple spring loaded latch which could be released by a string pulling towards the center of the body (or, more likely, towards the skeleton frame, which then uses a simple pulley to redirect it towards the body).
With this, you would lock the "skeleton" in a ridged stance and pull the latch string. That would open the latches, but the suit wouldn't open
until you start to walk out of it. The spring would gently and fluidly push the arm into an open position as you left it. Entering the suit, you release the tension on the latch string and press your arm in towards the "skeleton" frame. As you do so, the arms wrap around you, and when you're in all the way the latch springs lock the suit in place again.
How smooth the effect was would depend on how strong the spring is, how heavy the suit is, and having a method to lock the "skeleton" into a rigid position. The rigid position part was always going to need to happen if it was going to stand on it's own. The lighter the suit, the easier it will be to get a "skeleton" to hold it up. The spring will need to be stiff enough to push the armor plates apart, but gentle enough to bend without you putting too much force on the skeleton.
To apply the same technique to the fingers, you'd use some
very small hinges/latches. Each finger's "skeleton" part would have to connect to the back of the wrist in a way that could hold it rigid. You could then have the palm of the hand rotate as one big piece on a hinge opposite of the thumb (near the pinky finger), so it hangs down when out of the suit. This palm plate could have an additional curved groove that you rest your hand into when getting back into the suit, allowing you to rotate the palm back into position. This would give you a hand piece that you could get into and out of without having to pull at/having dangling gloves. I'm not so sure on this portion, because it'd be
a lot of very,
very tiny moving parts, but if you could somehow manufacture them then in theory it should work. Maybe some of the Ant Man cosplayers could give us a hand
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I'm still trying to think out how you'd make the frame rigid. So far all I've got is that you'd probably want a system of pins that extends over the joints to prevent them moving. To line up those pins, you'd basically want a funnel to guide them to where they should be. That's all super early brainstorming, mostly I just got excited about the idea above!
