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Magic Arms


  Another low budget 3D printed arm exoskeleton is one released by Magic Arms. This is the most advanced (lo budget) project so far and evolved from well known among children’s orthopedists WREX. WREX is acronym of Wilmington Robotic EXoskeleton and is apparatus for automating arm and grasping movement training for rehabilitation of patients with motor impairment, as stated in headline of its USpatent.
  Basically WREX design is more resistant to misalignment on the cost of complexity. It adds second arm to first stage of exoskeleton to always position elbow yaw axis equally and enlarge range of motion.
  I printed exoskeleton believed to be Magic Arms from files from my friend physiotherapist and tested with boy who was using Angel Arms before. I used Form Futura HDglass for its FDA approval and Carbonfill for its stiffness as a main materials. Unfortunately the device I made was too large (printed without scaling), heavy and coarse to give a good results. Main problem in case of double armed Magic Arms is friction between devices elements while being under twisting force. And it’s usual state when child’s forearm is 90 degrees to arm. Right approach here seems to be installation of bearings and decreasing the overall size of the device. Also the closer exoskeleton is to the body the better.



  I’m going to take second approach to Magic Arms slightly redesigned to use with bearings and slimmed. The videos of Magic Arms in action are promising.




  The Magic Arms is going to provide ready to use, easy to setup exoskeletons for kids. Thanks to 3D scanning and 3D printing technologies (not to mention design and web tools) now it’s possible worldwide. 




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