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Angel Arms


  The very first arm exoskeleton for kids with SMA I’ve discovered was Angel Arms. Designed by two biomedical engineering students Joseph Kissing and Brooks Schaefer at Grand Valley State University in Grand Rapids, Michigan was simple and beautiful piece of engineering. Its minimalist design use rubber bends to compensate hand weight thus allows less force to move.
  SMA – Spinal Muscular Atrophy is a neuromuscular disorder characterized by loss of motor neurons and progressive muscle wasting. Kids with SMA have very weak muscles and often couldn’t move their arms themselves. Thanks to initiatives like Angel Arms they can finally play, draw and throw a ball, but it’s still emerging field. There are medical companies that produce similar devices but they need a lot of measurements and custom fitting and can’t be ordered remotely because proper setup in their case is crucial and simply they doesn’t work if they’re misaligned. Moreover they need to be replaced multiple times during children growth and becomes too expensive for most parents.
  Low budget 3D printed Angel Arms open doors for frequent replacement on larger ones and general use for kids. This is really dirty cheap (unit for one hand weights less than 100g) and super easy to assembly. So can be 3D printed locally and made by parents themselves. Unfortunately it has also downsides. It’s difficult to mount, setup and operate. Even minor misalignment can prevent the device from working. I would suggest this for kids with milder SMA type (SMA3) as it can rally provide much fun for them. And for parents with basic mechanical skills as it need some of maintenance from time to time.

You can visit and download models from official Angel Arms source page here: https://www.patternspace.co/PatternSet/36

And here is one of polish users of Angel Arms printed by Golem 3D:





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