Wait Jeffe…I need to try something. I had upgraded the software a couple weeks ago but never actually installed the latest version. I just did that and found they have replaced the .pde with an INO file (attached). I’m going to go try it. And then I’ll have to figure out how to make the same changes if the steppers don’t step.
Doesn’t explain why the supplied sketch form the Arduino forum wasn’t working but still…
Gimme 10.
DFMocoVers4.zip (14.3 KB)
Verified OK. Flashed OK. But I’m not certain it’s gonna work straight up like that. But I’ll give it a whirl! I need to find a power supply first and set the pots. Then I’ll plug in a stepper. I think I have time to dig into it tonight.
Maybe you would know right from the get go based on what was supposed to be done to the .pde version whether I’m going to need to do the same to this INO version. I’m going to go in and see if the same lines of code exist actually…
[Edit]
Looks like it’s the same so I’m going to go ahead and try making those changes.
I can check it later, maybe tomorrow. I’m AFK now.
I made the edits and it compiled and uploaded. I’l play with the pots and try the steppers hopefully tonight. Thanks for the support!
Just reading through “next steps”. Am I right that I can just use a USB cable and a USB power block (the ones you plug into the wall to charge your phones/iPads etc) to power the Arduino. And then I need a second power supply with a good amp output rating (enough to cover the max stepper motor load - 4 Nema 17’s…same as the V1 Machine’s steppers) and with an output voltage of 12-36 volts?
12-36V 2A or better, no big deal, same as the one we use.
I used one of these board with grbl on it – that is correct for power, but the USB will need to be connected to a computer, not just a power block since the computer signal is needed to control the board. Hope that helps!
Ha! Thanks. I just came back to the laptop from the big box of eWaste under the stairs (power bricks, old routers etc) and thought “Wait a second…I need the USB plugged into the computer so it’s going to get power anyway!”
I did happen to find a 110V Input > 5v output at 2.5A complete with a plug that would fit the plug on the Uno but I need to verify the polarity if I were to consider using that. I’ll see if it self-powers through the computer first. I DID find a 12v @ 3A output brick. I’ll use that to get things set but it looks like I might want to invest in a new power supply like on the printers.
And the wife chastises me for keeping this stuff around…
For goodness sake. Don’t let her see all that stuff! This is the main advantage of being the one who vleans out the basement.
I put all that stuff in front so she doesn’t see the kite collection under there. I was a bit of a chronic in my old days…although this very thread could be evidence of a pattern in my life…
If anyone ever asks you say “Kelly who? Nope. Can’t say that rings a bell.”
Well, thanks a pant load (once again) guys! I’m super stoked that this project is DONE!
If you don’t quite get what’s going on here, the start of the test runs all the steppers back to their start position…technically these guys are supposed to be hooked up to camera sliders, pan and tilt heads, focus rings, objects that are to move on stage etc. When the test runs, the steppers jog to position #1 for the start frame, advance to the next spot for the second frame and so on and so on frame by frame as you animate. The steppers advance after each shot is taken but those shots are controlled by the animator. Once the puppets/props etc have been moved for the next shot you hit a capture button, the shot is taken and the steppers advance to the right spot for the next shot.
Accurate, programmable, repeatable and fine tuneable. With this set up I’ll be able to do complex camera moves and verify the shots will work and frame up properly before committing to the animation of the subjects on stage. Can’t wait to get this stuff hooked up to some gear!
FWIW - Stop motion animation is solidly placed on the “hobby” spectrum in my life and definitely not top priority. I’m still gathering and amassing gear for the “studio” which I have been doing slowly over the past six years or so. This $100 project has saved me THOUSANDS on commercial motion control gear. Literally. It’s a big milestone in my studio preparations. And one of the last big milestones…it may be time to start animating quite soon. Thanks again for the off-topic assistance! Beers all around!
One other thing…holy heat generator Batman! The heat coming off that Arduino/Shield is ridiculous. I set my pots to ~750mV (steppers rated at 1.7 Amps). Should I hook up a cooling fan or should I dial down the pots a bit?
Nice! Open hardware and open source software For The Win!
You should post your modified file back to the source to hopefully give the next Kelly that little leg up.
Personally, I would turn down the current. You’ll see a big reduction in heat if you do and you’re not milling aluminum, you’re moving a camera. It depends on the mechanics though. If you’ve got poor mechanical advantage you might need the torque.
Have you seen this? https://www.v1engineering.com/forum/topic/mostly-printed-camslider/
Your 12V 3A power supply is also technically being over worked. 750mV is 1.5Ax4 is 6A at 12V.
Thanks. I’ll turn them down to 500mV. I’m not sure how often I’ll ever run four steppers at once but I’ll be sure to keep an eye on the power supply. What would be the point of failure? Would it kill the power brick (which is fine) or could it fry the Arduino/Shield?
The point of failure is probably the PSU running at 9V instead of 12V or something. Eventually, something might get so hot as to pop (in the PSU).
Even if you’re not moving all the motors, if you have them enabled, they are each consuming 1A at 500mV. The current is on when they are stopped just to hold them in place.
As I understand it, the output current to the motors doesn’t translate directly to input current from the PSU. The motor controller acts somewhat like a buck converter, transforming higher voltage lower current input into lower voltage higher current output, using the inductance of the motor itself.
It’s hard to predict the input current, especially since it changes once things are moving. Best to just measure it. But don’t be surprised if it’s much less than the current through the motors.
So you know what the overarching wonder is that’s rolling around in my pea brain over all of this? At what point does the student become the teacher for me? I mean, how can I move from “following instructions” to paving the way? I fell down a rabbit hole late last night called “Otto Robot” and am now keen on playing with some nanos. These little computers or whatever the “proper” term is for them are so versatile it’s almost mind boggling. But without someone leading the way for me I’d just have a pile of boards around and no clue what to do with them.
The Moco project got me thinking - what if I wanted to build a stepper driven piece of home decor that required the stepper to give me 27 full rotations over a 12 hour period and then reverse over the next twelve hours? Where would I start looking to learn how to make that happen?
I have a few otto kits here for any of my friends older kids that show interest in my nerd stuff. I used a few nano’s in my college senior project, in the PID, and I have 50 or so on hand. All the arduino’s are crazy versatile, robust, and well documented. Get a kit with switches, buttons, screens and sensors and just play around. Pretty mind expanding when you start to get it. Heffe taught me about interrupts, leveled me up a bit…
I would start with two things separately…time how to use it on a Arduino, and How to drive a stepper with a nano. Then add them together.
27 rotations and 200 steps per full step and 16 steps per full step = 86,400 steps per day.
24 hours, 60 minutes, 60 second = … what? 86,400!
Just run the blink sketch! Oh wait, you want just 12 hours.
If you’re ok with slop, you can use a lot of basic techniques to count. If it needs to be precise, because it’s a clock, then you’ll need an external source for a clock. Either ntp and wifi, a real time clock with a battery, or a GPS receiver.
As for becoming a teacher, it’s not really binary like that. You could help Kelly from just a few months ago and you’ll get more capable with each project. There is an enormous amount to learn though, so don’t be surprised if you are still following directions a few years from now. Personally, I have my engineering degrees, and a lot of on the job experience, and I’ve watched a ton of videos. I used to go through all the adafruit and sparkfun tutorials.