

Why We're Giving Away Free Robots - jennyjenjen
https://medium.com/@carbonrobotics/we-want-to-give-you-a-free-robot-ed64d5c338ea

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sbierwagen
Would really like to see some actual technical information on the arm.
Payload, speed, accuracy, etc.

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jennyjenjen
Absolutely! Payload is 1kg at extension, speed is 2 seconds between any two
points, accuracy is sub-millimeter. It's got the capabilities of an industrial
arm for the price of a laptop.

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pravda
Power requirements? What's in it... steppers, servos?

"Guide the arm through a motion, which it replays flawlessly" \-- ok, I assume
it has servo motors with encoders.

The motors are in the base with timing belts extending to the joints?
Backlash? Rigidity?

What's it made of? I assume it is not carbon fiber. :-)

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rmyers
Hi! Co-founder here...

KATIA plugs into a normal wall jack (120/240v single-phase), so you don't need
to be wired for 360v three-phase power like you would with other industrial
robots.

We also don't use any steppers or hobby servos like you would find on a toy
arm. When we say the performance of an industrial arm, we mean it. We've built
highly integrated, custom permanent magnet synchronous motors with 14-bit
absolute rotary position sensors built into each joint.

Furthermore, the arm has been designed from the ground up for zero-backlash
operation, and the rigidity is insane -- we're gettting less than one hundreth
of a millimeter of transient deflection during our worst-case stress testing.

And it is made out of carbon fiber, because that's just how we roll.

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pravda
Well, I am very impressed.

14 bit = 2^14 = 16384. Optical or some kind of hall-effect? I am going to
guess hall-effect.

When I read "permanent magnet synchronous motor" I think stepper-ish motor. Is
that what the joints are? No gearbox, custom stepper-ish motor, with the
14-bit encoder giving feedback not just on the position, but also the load?

What voltage do these custom motors run on? I will guess .... 48V.

It is a very sleek-looking arm.

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sbierwagen

      the 14-bit encoder giving feedback not just on the 
      position, but also the load?
    

Rotary encoder probably wouldn't give you that. Usually you just measure how
much current the motor's drawing.

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cranium
I want to see the robot :'(

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jennyjenjen
We are about ready to make some demo videos! Check out our page main site
[http://carbon.ai](http://carbon.ai) and there's a video of one of our first
arms - not a rendering.

