CVT Arm #3 (Patreon)

CVT Arm #3 = PREVIEW VERSION

This is part 3 of the one-motor robot arm, which uses three continuously variable transmission clutches to translate the motor drive to three axes. This isn’t a totally practical way to make a robot arm, but I wanted to see if it could be controlled electronically and if we can run inverse-kinematics on it. Mostly it’s an experimental project, although it’s a little bit like a Hydraulic system which normally has one engine driving a hydraulic pump, and then multiple valves which switch the fluid to multiple hydraulic cylinders. In my case though, my valves are actually continuously-variable transmissions which use ball-shaped clutches. As the ball tilts a larger or smaller part of the circumference runs between two wheels, giving either a reduction or enlargement in velocity. There’s also a dead-spot in the middle so we can stop a specific axis with no friction. I’ve used worm gears to lock the axes in place while the clutch is at its dead-spot so they doesn’t free-wheel. I’d previously made a two-wheeled differential drive robot using this system which worked well, but I’ve now expanded to three axes. The first one drives the whole robot around on its base which is made from a lazy Susan bearing - the clutch drives a spur gear around the inside of a large ring gear. Axes two and three drive the shoulder and elbow of the robot. Two drive shafts exit the gearbox at the top, equally spaced from the centre of the robot. I then used a series of bevel gears to make a differential drive system that translates the motion to the shoulder and elbow axis. You can support me on Patreon or buy my Merchandise: *************************** Patreon: https://www.patreon.com/xrobots Merchandise: https://teespring.com/stores/james-bruton *************************** Affiliate links - I will get some money of you use them to sign up or buy something: *************************** Matterhackers 3D printing supplies: http://www.matterhackers.com?aff=7500 Music for your YouTube videos: http://share.epidemicsound.com/xrobots *************************** Other socials: *************************** Instagram: https://www.instagram.com/xrobotsuk Facebook: https://www.facebook.com/xrobotsuk/ Twitter: https://twitter.com/xrobotsuk *************************** CAD and Code for my projects: https://github.com/XRobots Huge thanks to my Patrons, without whom my standard of living would drastically decline. Like, inside out-Farm Foods bag decline. Plus a very special shoutout to Lulzbot, Inc who keep me in LulzBot 3D printers and support me via Patreon. HARDWARE/SOFTWARE Below you can also find a lot of the typical tools, equipment and supplies used in my projects: Filament from: https://www.3dfuel.com/ Lulzbot 3D Printers: http://bit.ly/2Sj6nil Bearings from: https://simplybearings.co.uk/ Lincoln Electric Welder: https://bit.ly/2Rqhqos CNC Router: https://bit.ly/2QdsNjt Ryobi Tools: http://bit.ly/2RhArcD Axminster Micro Lathe: http://bit.ly/2Sj6eeN 3D Printer Filament: http://bit.ly/2PdcdUu Soldering Iron: http://bit.ly/2DrNWDR Vectric CNC Software: http://bit.ly/2zxpZqv Why not join my community, who are mostly made up of actual geniuses. There’s a Facebook group and everything: https://www.facebook.com/groups/287089964833488/ XROBOTS Former toy designer, current YouTube maker and general robotics, electrical and mechanical engineer, I’m a fan of doing it yourself and innovation by trial and error. My channel is where I share some of my useful and not-so-useful inventions, designs and maker advice. Iron Man is my go-to cosplay, and 3D printing can solve most issues - broken bolts, missing parts, world hunger, you name it. XRobots is the community around my content where you can get in touch, share tips and advice, and more build FAQs, schematics and designs are also available.