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Topic: ArduDelta - delta Robot implementation (Read 17 times) previous topic - next topic

body28

Hello Zozerk and thank you.
The code is attached to my previous post.
The kinematic functions are also embedded in the project.

Just ask if you need more help, and good luck with your project.

howiem

Wow - beautiful work. I love the tripod-like legs, and the way they curve under to support the base plate. Simple and elegant.

May I ask - what reasons made you choose servos rather than stepper motors?

I suspect that servos will never let you get quite the accuracy you want; different servos may accelerate and decelerate at subtly different rates, and there's a lot of slack/backlash in the internal gears which doesn't matter when you're just using a servo to get from angle A to angle B, but will make a big difference if you want the combined velocity from all three to be precise and repeatable. Plus the internal gearboxes have quite a bit of 'bounce' in them, which may be hard to engineer around.

Having said that, I dread to think what the code would look like for stepper motors - it's a big leap to go from smoothly ramping three PWM signals over time, to sending out between three and six streams of variably timed pulses where the timing itself is non-trivial to work out and needs to run smoothly.

(I managed to build a crude CNC mill out of bits and pieces, and I naively thought it would simple to get an Arduino to not just act as an interface, but actually be capable of doing simple jobs itself - draw/cut circles, that sort of thing. When I actually started to have a go, I found the code waaaay more complex than I could handle. One axis, accelerating and decelerating from A to B was simple enough, but add another axis into the mix and it gets much more complicated... I gave up and started using TurboCNC. Gave me an enormous amount of respect for the guy who wrote it - there's a lot of funky maths going on in there :)

Cool remote control and display, too. Next step: ethernet shield and a webcam, so we can all have a go at writing our names with it? ;)


fgarrido

nice!
I couldnĀ“t find the code anywhere!
can you share it?

thanks! (from Argentina)

fg

alegiaco

Your ball joints are very interesting. Where can I buy these joints? Thanks.

IVANMONSAO

Hi, your project is awesome, I would like to have the code, is it possible?
ivan.monsao@gmail.com

Congratulations, Ivan

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