Loading video...

Video Failed to Load

Go Home

A little weekend side-project, trying out gravity comp with PWM controls on an so-101 It holds but feels very stiff, the giant gear ratios probably impact backdriveability. Will see if any AI/SW tricks can mitigate, would prefer keeping standard servos Pepijn 🦾

16,106 views • 2 months ago •via X (Twitter)

11 Comments

Jason Liu's profile picture
Jason Liu2 months ago

@pepijn2233 stiction compensation can help a lot if you haven’t tried it already

Embedr's profile picture
Embedr2 months ago

@pepijn2233 that limb is looking dangerously close to gaining free will

Paolo AI's profile picture
Paolo AI2 months ago

@pepijn2233 Let's compare notes I did the same for the ElRobot arm.

Ville🤖's profile picture
Ville🤖2 months ago

@pepijn2233 > "these motors only have position control" this is not right for feetechs, they offer direct pwm control as well which allows us to approximate voltage & current control. this is the correct way to implement gravity comp rather than using position control

Paolo AI's profile picture
Paolo AI2 months ago

@pepijn2233 I like your approach with PWM I am going to test it too.

atharva ☆'s profile picture
atharva ☆2 months ago

@pepijn2233 share code I think I can help you with this

Ville🤖's profile picture
Ville🤖2 months ago

@pepijn2233 I will eventually but it's not ready yet, what part might you be able to help out with?

Praveen Selvaraj's profile picture
Praveen Selvaraj2 months ago

@pepijn2233 should make teleop easier right, esp bimanual ?

Ville🤖's profile picture
Ville🤖2 months ago

@pepijn2233 it's step 1/n on that journey and I'm not sure if all steps are feasible on these motors

Makr3D's profile picture
Makr3D2 months ago

@pepijn2233 The standard servos may still be workable if the gravity term stays deliberately conservative. Have you measured backdrive torque across the joint range yet? That would help separate gearbox friction from controller stiffness before adding more software compensation.

Yuv Bindal's profile picture
Yuv Bindal1 month ago

@pepijn2233 gravity comp on a so101 is fiddly. connect sometime

Related Videos

Elon Musk on Grok: “I think an AI that is sort of SpaceX’s baby will be a very good AI. I think SpaceX is a collection of some of the very best humans on Earth, both in capability and morality and goodness, and I think we want to have an AI that is born of that capability and that morality and that goodness. I think that’s very, very important. So I’d like to encourage people to help out, actually, with the AI hardware on the ground and the AI software and, of course, with the AI satellites. Solar is going to be a very important part of that. The TerraFab will be a very important part of that, but we must also succeed on the software front, and we’re going to be training Grok on the sum total of all SpaceX information. So in a way, it will be trained on you. You will effectively be the parents of the AI. It will inherit your thoughts and ideas and beliefs, and I think that’s a good thing. So, yeah, we’ve got to win here on the AI hardware and the AI software. That maybe is the most important message. I think that is actually the most important message I wanted to convey today is that we must win on AI because the future is overwhelmingly AI and robots. So we won’t ultimately be able to control the AI. It’ll be too smart for that. But just like if you have a child that is a super genius child, you can still instill in that child the values and beliefs that you think are good and right. And so that’s why it’s incredibly important that we succeed with Grok. So, yeah, well, Grok 4.5 you’ve tried probably. We’ve got 4.6 coming out in about a week. And then 4.7 should be really pretty special. So I’d like to encourage everyone at SpaceX to use AI and to make it better.”

DogeDesigner

64,434 views • 1 month ago