The space industry has been developing the "in-space manufacturing" approach for years - printing tools and parts on demand right in orbit: an additive manufacturing facility for the production of plastic elements is operating on the ISS, and Europe has already demonstrated the printing of a metal part in space.
Researchers from the Massachusetts Institute of Technology (WITH) offer an alternative - printing of an electric machine right on the spot, without being tied to global supply chains. The team created a multi-material extrusion 3D printing platform, able to manufacture electrical devices. Such a multi-material platform takes a step from housings and brackets to full-fledged electromechanics - they printed a working electric linear motor in a few hours, that is, potentially the same drives, which drive precise positioning mechanisms in robots, devices and optical systems.
The system uses four extrusion tools and can handle multiple functional materials, in particular, electrically conductive and magnetic. At the demonstration, scientists printed an electric linear motor (actuator, which creates rectilinear motion) from five materials in a matter of hours; only one post-processing step is required after printing. It took about three hours to make the prototype, and the material costs were approx 50 cents.
According to MIT, the assembled device worked no worse, and sometimes even better than analogues, which require more complex production or additional operations. A key engineering challenge is to match materials with very different requirements: conductors are squeezed out under pressure, whereas filaments or pellets require heating. So that the layers match exactly, the platform uses sensors and a control system for highly repeatable tool positioning. In the future, the researchers want to integrate magnetization directly into the printing process and progress to fully printed rotary electric motors.
Maintainability and autonomy are critical for space missions: when the knot breaks, waiting for supplies from Earth is expensive and long. A print-on-site approach potentially reduces the need to stock a large inventory of spare parts and speeds up the recovery of robots/mechanisms. Linear actuators are also used in optical systems (positioning, focusing, delivery mechanisms), so rapid fabrication of custom actuators can be useful for tools as well, who work in astronomy and related laboratories.
Source: https://universemagazine.com