Arduino Setworks (with video!)

[hackberry jake]

I am in my last semester at the community college to get an associates degree. I have a class called "programing logic" which is handy and all but the people in it are extremely smart electronics students. I have been telling them about sawmilling and they have been helping me through understanding logic. They enlightened me to a thing called an "Arduino". Its a $30 board you can buy online that can be programed to do all kinds of functions. It's exactly like a mini computer without a screen, but you can buy a screen and have it display certain variables. I am pretty sure I can build a highly accurate setwork system for under $400. Program the Arduino and have it send info to a stepper driver, the driver controls the stepper motor and your head moves up and down in precise incriments.
At the moment I am thinking about having a button for 4", a button for 1", a button for 1/4", and a button for 1/16". There would also be an "up" button and a "down" button that would finalize the command. I may change the set-up a bit as I learn more about all thats involved. to lower the head 5 1/2 inches you would hit the 4, then the 1, then hit the 1/4 button twice and once you hit the down button it would "send" the command and the sawhead would lower. What you guys think?

[drobertson]

sounds like C++ programming, very doable,   david

[beenthere]

Anxious to see it put to work.
When do you start? 

Where will you pick up the needed parts.. board, stepper motor, and the stepper driver? 

Does the stepper driver start out with 'slow' steps and ramp up to a cruise speed and then ramp down slowing to the final step?

Will you drive it through a timing belt or a roller chain, or other means?

http://en.wikipedia.org/wiki/Arduino               

[hackberry jake]

sounds like C++ programming, very doable,   david

Exactly 
Board comes from spark, driver from gecko, and stepper from keling cnc.
As far as ramping speed that is very doable, but I imagine I will save some money on steppers and use a pretty high reduction so I can get away with one medium sized stepper instead of two big ones. I would likley just leave the speed pretty high since it is hooked up to reduction.
I will likley use acme threaded rod for travel up and down and they will be tied together with chain and sprockets.
This is assuming I actually do it. I was mainly throwing it out for people that may need it more than me and for general discussion.

[wildbill]

if you can think it you can program an arduino to do it.

you will want a motor driver shield to pair with the arduino.  the arduino alone cannot output enough voltage or amps to drive much of anything.  for the motor required to move a saw head you may end up making your own motor driver to pair with the arduino. 

the ones i have are a few years old and use the ATMega328 chip.  it gives me 12 digital I/O's and 5 analog I/O's.  while the arduino may cost 30-50 depending on the model you choose it is the ATMega chip that is actually doing everything.  everything else on the board is there to make it easier to program and connect to.  the last time i bought some chips alone they were about $5 each.  after the programming is done you pull the chip and put it in its own circuit board as a stand alone unit.  cutting your costs way down.  just be sure to buy the chips that have the bootloader already burned in the chip.

the possibilities are limitless with these little PLCs.  if you can dream it and build it mechanically you can program an arduino to control it

[POSTON WIDEHEAD]

I have no idea what y'all are talking about but boy am I a reading.  :D

[beenthere]

. I was mainly throwing it out for people that may need it more than me and for general discussion.

We can't let ya off that easy.....   ;D

Well.... today being "HuuMP" day, maybe 'til next week.

[pineywoods]

Member Shaworth did a lot of work on such a project. He and I corresponded a bit viaPM and there are a few posts on here. There are a bunch of hidden gotcha's. A stepper motor and driver big enough to drive a sawhead up and down will cost some serious money. Another solution is use a hefty DC motor driven by a mosfet H bridge. (ask your electronics buddies) Most head lift mechanisms use some type of rotary motion. Attach a small magnet and use a hall effect pickup feeding the micro processor to count revolutions. Then there is the problem of stopping the head right where you want it. A sawhead is heavy and it will continue to coast downward after drive power is removed. How much ? Depends, fuel tank full or empty, water tank full or empty. lube on the posts , sawdust in the mechanics. There are solutions, but it ain't as simple as it looks.
Jake, if you pursue such a project, I would certainly like to be involved. Ill se if I can find Shannon's posts..


Found it. click here
https://forestryforum.com/board/index.php/topic,40770.msg586731.html#msg586731

[wildbill]

another option for setting level of movement is using a potentiometer.  if resistance = 0 dont move.  if resistance = 1ohm move 1/4" down

4ohm would be 1", 8ohm 2" and so on.  wouldnt have to be that much resistance either could be in the milliohms just as long as the arduino knows what each level means to you.  once the level is set say at 8ohms press the "lock button" and with each pass the head moves down 2" no matter the position of the dial.  a small LCD would show you the level you are set at, if you are locked in or not and anything else you wanted to hook up to the unit to know about (blade RPM?, oil pressure?, temperature?)

with the extra I/O's you lube water could be turned on and off automatically.  possibly a sensor telling how much force is needed to push through the wood (telling if your blade is getting dull or if your speed isnt right?)  im at my limits of what i think i know about a sawmill

[pat smith]

I think i'm on the wrong page lol!!!not for sure!!!confused a little!! ??? ???

[hackberry jake]

The arduino wont drive the stepper, a stepper driver will. The arduino just generates the step and direction and the driver does the heavy lifting. With a spring or counterweight you will get plenty of power out of a stepper. I have some 906 oz stepper on my cnc and I am almost sure it could break my arm.

[hackberry jake]

I dont know what kind of driver is needed but ill bet one of these would be plenty powerful enough
http://www.surpluscenter.com/130-VAC-185-IN-LB-STEPPER-MOTOR-6-5A/edp_no=45120/shop.axd/ProductDetails
I have only dealt with dc steppers. Ill have to research ac steppers.

[wildbill]

https://www.sparkfun.com/products/9107

a quick search gave me this.  15A-21A(with heatsink)

its not made for a stepper motor and is for a DC motor but its a step in the right direction

[pri0ritize]

It looks like you're going down the right path Jake. Everyone has given you good advice. Would suggest you price things at Digikey and I would also suggest you use a 32 or 64 character display and a few buttons to set the amount of movement. The display can be had for a couple dollars and will make the setworks much more usable. You could have two momentary buttons for increase and decrease increment and two buttons for move up and down.

I write embedded code for a living. Which language will you be using?

[pri0ritize]

Also, pay attention when you pick an Arduino. Most of the newer ones use 3.3V logic and the gecko driver needs 5V steps.

[hackberry jake]

https://www.sparkfun.com/products/9107

a quick search gave me this.  15A-21A(with heatsink)

its not made for a stepper motor and is for a DC motor but its a step in the right direction

If I went this way, I would also need an encoder... which adds a lot of complexity... I think  ???
The class I am taking is c++. But im sure it uses a different language. I should be able to figure out enough to do simple functions like setworks I hope. Maybe ill pm you and you could write my code if I go through with it? ;D

[47sawdust]

 Ah,yes,Pineywoods and the hidden gotcha's.They show up here more than I'd like.I think the next gizmo for Jake to be build is a Gotcha Alarm.It would be a best seller,especially if it was set to anticipate the said gotcha.
I too have no idea what your talking about,but that seems to happen more these days.

[bandmiller2]

Old curmudgeon here,what are you guys trying to do turn milling into a video game,replacing sawyer skill with micro chips.Milling is a simple mechanical function best handled in a simple dependable way.Look through past problem posts on this forum almost always its electronics.I'am not saying don't do it but just have a manual backup when you just have to get an order out.Flak jacket on, have at me guys. Frank C.

[drobertson]

A big ten four on the manual back up! Just in case,       david

[Leigh Family Farm]

Contact Make Magazine. They would love to hear about your Adruino project. As for the coding, search the web. There are a lot of resources out there that have the coding for many applicaitons already completed and are completly free.

Another application that the Adruino can do is link together with other Adruino units and create a huge sensory mechanism that will give you not only the ability to set your cut depth, but the number of cuts made, the width of each board removed from the mill, bdft yeild, catalog the bdft total for a customer, bdft per day rate, average bdft per day over a given time period, engine temp, average blade life, and on and on and on...

Bandmiller2, certain skills do need to be learned and there are no shortcuts to learning them. I am all for learning new skills and crafts, and I hope to teach my son one day the same skills. Some things are just done because we can, not neccissarily because we need to or the old crumugeon way  ;) is broken.

P.S. We don't use flak guns anymore.  ;) ;D

[downsouth]

Wow, Jake that boardwalk jr will sure be worth some money when you get finished with it.
  I too am lost but, seems pretty cool. I'm still trying to put together some hydraulics on mine.

[pri0ritize]

I'd be more than happy to help you with your code. I've been working on a accuset type setworks using servos in my spare time, which has been very limited lately due to me building a house, getting married and spending 5 weeks on travel for work. Getting to see a bit of the East coast though! Let me know any questions you come up with. Most aTMega programming is done in C...or assembly.

[hackberry jake]

Well... an  "arduino uno" should be here by Tuesday or Wednesday. The way I look at it, I have a spare break out board, and power supply from the cnc router build. And the rest of the parts I can borrow from the cnc router to get the setworks going. If it works good then I will order replacement parts for the router. If it doesnt cooperate and I pull half my hair out trying to get it going, im out $30.

[MSSawmill]

Very cool idea, Jake! I haven't had a good excuse to play with an Arduino, but I've been looking at them for quite a while. They are extremely cool little devices.

It's been a while since I did any C++ programming, but I still do a lot of scripting so maybe I can help with the logic part of the code. I'll definitely be watching the thread. Good luck!

[scsmith42]

Jake, great idea and I think that you should definitely go for it.  If nothing else, the knowledge that you gain from this project will be a great asset in the future.

Keep us posted.

Scott