3D-printed bend-based mechanism

It might look like some bizarre alien artwork but this is actually a frictionless gear mechanism, 3D-printed all in one in high-performance stainless steel, designed to enable the precise rotation of items such as satellite thrusters, sensors, telescope lenses or mirrors.

Standard moving parts in space involve friction, and therefore require some kind of lubrication that can potentially lead to unwanted contamination of delicate systems, while also inducing ongoing wear and tear and reducing overall operating life.

By contrast, this is an example of a ‘compliant mechanism’ that transmit force through bending, or ‘elastic deformation’, such as bag fasteners or bows and arrows. Incorporating 24 bendable blades, of which 16 are interlocking, the design serves to reduce the rotation angle by a factor of 10, so to allow a rotary motion with very fine resolution and high repeatability.

ESA Technical Officer Paolo Zaltron explains: “The deformable and rigid parts are built together as one single monolithic structure, avoiding any time-consuming assembly and alignment. Their unusual shapes pushed the boundaries of Additive Manufacturing technologies and are the result of advanced optimization techniques that lead to unprecedented high flexibility and low mass.”

This Compliant Rotation Reduction Mechanism was designed by CSEM in Switzerland, with Swiss company 3D Precision SA undertaking the 3D printing while its performance testing was undertaken by Almatech SA, as part of an ESA Technology Development Element activity.

See a video of the mechanism in operation here. For more details of the activity, click here.