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afcorson
Australia
Asked
Resolved by Dave Schulpius!
Servos Suited For Legs
Can anyone provide some advice on high torque servos suitable to use for robot legs? I just finished installing the standard EZ robot HDD servos - one in each hip and one in each knee. When powering up, the robot will topple over as these servos are not strong enough to hold it up (the start up position is 90 degrees). My robot is 4' high and the top half weighs a lot more than its legs. I want the robot to slide walk, not lifting the leg at all. CR servos will be in the feet.
Any advice would be appreciated.
Related Hardware EZ-B v4
There are a few options out there. There are a number of Dynamixel servos from Robotis that would likely fit the bill. Otherwise, you can look at the servos that are used in the inMoov project, but be aware that they are a much larger form factor. HS-805BB and TS-80 are some servos that are used by the inMoov. I would suggest though to find a digital servo because the noise with analog servos for a walking robot would be unbearable. You could also look at augmenting the EZ-Robot HDD servos with 3D printed gearing to increase the torque. The worm gear in the inMoov shoulder is a good example. There is also the openDog project by James Bruton for another idea for driving robot legs.
Any way you look at it, legs for a 4-foot tall robot is a large challenge, you will likely need to engineer a few different prototype ideas.
I forgot that James Bruton also did a humanoid leg project, and there was a 5-foot robot with legs here in the community as well. The robot here moved by slide walking as you described. Hopefully, another community member can remember that post.
afcorson
did you print the chest ? very cool robot.
Nice robot, but those servos will not have enough power to operate it...you should have done some testing before building the whole thing I guess! But don't let this bring you down, failing is always a good lesson and I am sure you will be improving your build soon!
Hope to see updates on this one, its beautiful!!
I found it! It's HAL the robot that walks and talks
https://synthiam.com/Community/Robots/HAL-THE-ROBOT-THAT-WALKS-AND-TALKS-18477
That's a great bot and I'm surprised nobody has made the link as to what it is yet.
As a hint, I would love to see it with a Dr. Theopolis around his neck. Beee De Beee De Beee De
Hi Nomad, Hi, Perry_S, you said you have the same 3d printer as I have, any does and don'ts?, pointers?
EzAng
Hi EzAng - no real advice. I was able to just use mine out of the box. Use Simplify 3D as a slicer.