Monday 18 August 2014

Harmonic Drive Update 3

Well I found some time to work on the harmonic drive the other day. I achived
about 5.8 Nm of torque reliably during testing the drive slipped when i applied a
17Nm load. When I examined the drive i found  the wave generator was not
forming the flex spline correctly I upgraded the drive to use 2 608 bearings but still not working as good as i hoped. After a bit of research i found a better wave generator design using a elliptical plug and a thin wall bearing the challenge was to design it in CAD then print it after a few tries I had a wave generator that worked at high speed and wouldn’t slip. My test drive is not up to the task of
testing so I need to reprint the whole thing again . Instead of using a gear motor I want to use a Nema 17 stepper motor and fit the encoder in the side. Below is the steering actuator from omni_bot2


Below is my latest wave generator, the flex spline is printed in nylon and is holding up well the print quality is bad with the teeth being a bit smaller then they should be




6 comments:

  1. very nice idea to use a nema motor with encoder

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    1. Thank you i hope to have a working version soon

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  2. You are making excellent progress and it is helpful for people to read your blog to discover more about how robotics work.

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  3. nice! Do you also have CAD files and codes available?

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    1. I will release files for the final version that will be some time away as
      I don’t have that much time for this project. You can look at the source for this project at http://www.thingiverse.com/thing:20177

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  4. Hallo Peter,
    FYI: http://www.ros.org/news/2014/10/announcing-package-for-the-schunk-servo-electric-5-finger-gripping-hand-svh.html

    ReplyDelete