I'm currently designing some small-scale robots capable of both melee and laser-tag combat. For the melee component, I'd like to create small, ejectable panels that hide the laser-tag receivers. When hit, these panels would pop off exposing the receivers.
However, I'm having trouble finding a suitable mechanism to fit my constraints. Ideally the mechanism would be: small/shallow, so as not to stick out too far from the robot and either 3D-printable or low-cost. My first thought was the mechanisms in pens which don't seem accessible without disassembling a ton of pens, or push-to-open cabinet latches which are too large to use. I've also ruled out something like an electromagnet and push-button as that would add unwanted circuit complexity. Is there another mechanism that would serve this purpose?