Simulating basic spring / return force

[twrig144]

I'm designing an object dropped that uses two trapdoors actuated by a single servo, and I was wondering if there was any way to make the trapdoors automatically return towards what will be their closed state on the model (I'll use rubber bands on the real thing). 

I've attached three screenshots of the underside of the mechanism; the orange is the fixed piece and the blue pieces are the trapdoors. The servo is in the middle. I've got the trapdoors and servo linkage in the same contact set, so I can drag the linkage to move the trapdoors, but is there an easy way to get the trapdoors to return on their own?

[swalton]

I usually start with a quick hand calculation based on a Free Body Diagram.  That gives me enough info for a preliminary size of the various components.  If I don't care about the details of the motion, I will stop there.

If I need to understand the system behavior through the entire range of motion, I'd use Inventor's Dynamic Simulation tool to solve the rigid body kinematics of the system.  From there, I might export the peak loads on individual components to Inventor FEA or Inventor Nastran to confirm stress and deformation.

[JDMather]

Attach your assembly here if you can’t figure out how to add a Spring Force.

[twrig144]

Thanks for the response, to clarify further, I'm not looking for a realistic representation of the spring size required, just a way to have the parts move back to into place so that I can take a screen recording of the system operating.

Cheers,

[twrig144]

Thanks for the response, as I told JDMather, I'm not looking for the most realistic representation of a spring / force required to actuate, I'd just like to be able to have the trapdoors move back on their own when not being actuated by the servo arm.

[Lucas.dolinarVFXZU]

With @Anonymous you can notify them without having to write the message again...

About the Assembly: check the constraint created to solve this problem.
Furthermore, try not to use that many components in your contact set, it is heavy on your computer.