Compliant mechanism

Some common devices that use compliant mechanisms are backpack latches and paper clips.

Expected loading and desired motion and force transmission are input and the system is optimized for weight, accuracy, and minimum stresses.

Also, the forces applied by the mechanism are limited to the loads the structural elements can withstand without failure.

This, combined with the fact that mechanisms tend to perform cyclic or periodic motion, can cause fatigue and eventual failure of the structure.

Some designs of catapults also made use of the flexibility of the arm to store and release energy to launch the projectile larger distances.

[1] Compliant mechanisms are used in a variety of fields such as adaptive structures and biomedical devices.

These systems benefit from the lack of required assembly and simple planar shape of the structure which can be easily manufactured using photolithography.