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This is a WIP of a cycloidal gearbox with a reduction ratio of 40:1.
It is driven by a Tarot 4108 brushless motor, in theory it should have almost zero backlash...
By Mickey666Maus
— Last update
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Actually I thought, I'll just throw my actuator in this thread to start the discussion!!
I got it working now, but the vibration is really heavy...lets see if I can reduce it some more!
What were your issues?
I will put together some links for Cycloidal Gearboxes that I used to build mine...
Which CAD software are you using?
I will upload all the .stl files once I got that gearbox ready!
@DJSures that looks great!! I am also following quiet a few quadrupets, James Bruton has two versions that he is currently working on...seems like elastic actuators are a big deal, when it comes to building a walking robot!!
Super interesting!!!
It would be great to have a robot that can adjust the force according to what is actually needed!!
Great idea!!
@Mickey - The problem I had with cycloidals is the vibration. You see from how they are put together that the cam that drives the process of the motor is inherently not balanced. There are two stage ones that try to fix that but as a rotating assembly they are not ideal.
But then again, you can see him failing and progressing...which is also a nice thing!!
Anyways, there should be more content like the one that he puts out...great channel!!
If you take a closer look at my reducer, you can see that it is a dual cycloidal disk driving the output...the disks are set to opposing sides, so the center of mass always stays in the middle!
Still vibration is quiet high...
I think there is another problem with the output shaft, that I need to fix...I will have to wrap my head around it, and look at a few other projects. Hope I can get it done!!
I made a quick showcase of the actuator...it is very noisy and has a lot of vibration!
I had to change Dongil Chois original design because I am using a different motor.
And am not sure if a printed Cycloid Gearbox just sounds like this, or if there is too much friction caused by the eccentric shaft?
There might also be too little space between the disks so the torque twist makes them collide?
Any ideas on what to improve?
Or am I on the wrong path here...
The one with the toothbelt might have been a Harmonic Reducer, also called Strain Wave Reducer...this would be the optimal robotic gearbox, but I never found someone managing to design one that is 3D printable!
The gearbox needs a lot of bearings, but let me know if you would like to print one, and I will upload the .stl files!!
What is your thoughts on this.
I am not sure if this is the better choice over a printed one...but it would surely offer all the needed material properties needed for that part!
What do you guys think?
So I got the gearbox setup with the encoder working...it is actually less vibration than expected, I will make more stress tests under load!
Looking good so far!!
Also ARC integration is super easy!!
Looking forward to your torque testing.
The motors and bearings were ordered from China, do quiet cheap but as we all know...its a waiting game!!
I think the cost should be less than 150 per joint!!
But a 3d printed gearbox still is a 3d printed gearbox after all...lets see how it'll hold up during some stress tests!!