Homegrown Setworks

[shaworth]

Pineywoods,

On this topic http://www.forestryforum.com/board/index.php?topic=40761.msg586561 my brother let slip that he and I have been building a home grown "setworks".  You asked for more information, and rather than hijack the existing thread I decided to start a new one. 

It all started when I dropped by his place to watch him cut one of his first logs.  I couldn't believe that the up/down adjustment was being done "by eye" and boldly declared I could easily make a digital height adjustment for his saw.  Since then I've learned that such a thing has the official name of "Setworks".  I've never seen so much as a picture of Setworks, so I'm not sure this replaces it.  But my brother (victorh) seems pretty happy, and that's the point.

Since then I've been a lot more careful about shooting my mouth off around my brother.  It hasn't been as easy as I expected. 

Many, many hours later I've nearly finished a custom micro-controller circuit that will allow the operator to move and stop the saw-head with 1/32" precision.  The software has been written.  I've worked out how to measure the movement of the sawhead with the required precision (A hall-effect sensor is used near the motor to count motor revolutions).  I've got a schematic of the saw and understand exactly how to interface with the existing electrical system.  In short all of the parts are in place and mostly tested.

Last night I finished the preliminary control board case:  --Photos MUST be in the Forestry Forum gallery!!!!!--/yc8cgkd and it looks good.  You can browse those picture to get a sense of what it has taken to build the gadget.  This weekend I plan to drag the whole shooting match and install it into my brother's beloved saw.  Assuming my job and family don't interfere. 

It gadget works like this.  The operator to enters a distance, say 4" inches, into the system.  The operator then holds down the green button to indicate that the system should stop the saw-head at the designated position and uses the existing lever to move the head.  When the head reaches that position, the electric motor that moves the saw-head motor is stopped.

If you don't hold the green button when you start moving the saw head, the saw works just like it always did. 

It is actually pretty simple to operate.  Since I don't own a saw, I'm using a garage door opener to test with.  The neighbors must wonder why my garage door won't stay closed. 

Pineywoods, I hope that satisfies your curiosity.  Let me know if you want more info.

Thanks,

Shannon

P.S. Can someone tell me how to embed photos and URL's into my posts? 

[beenthere]

Welcome to the forum. Anxious to see what you designed and fabricated. I'm envious of your ability to put this type of control together. Just out of reach for my skills, but not my interest and a bit of understanding.

Pics are easy, and just need to set up a gallery for yourself, and use the Java uploader (see the way below this blue window) and/or go to the "Behind the Forum" Board on the Home page for a good tutorial. The .jpg file needs to be somewhere in your computer so you just click on the Java Uploader and brouse for your pic. The resizing will be done automatically for you, and the pics will be at the full 500 pixel limit.

[VictorH]

I will add that my brothers proposal came after hearing that the factory setworks was only available for 97 and newer units.  I've got a 95. 

[ronwood]

Shannon,

Welcome to the forum.

I bought the new Simple Setworks for my Woodmizer. Thought about doing my own also but as you seen it takes quite a bit of work. My mill is a 2003 and the sensor is mounted on the pully of the gearbox instead of the motor. Another thing to make sure if it is on a Woodmizer that the chain on the up/down is tension per service manual.

Ron

[Magicman]

Welcome to FF shaworth.  Looks/sounds like you've been here, at least in spirit, for a while.  Good luck with your project.  I'm interested in hearing about your results.

[shaworth]

Shannon,

Welcome to the forum.

I bought the new Simple Setworks for my Woodmizer. Thought about doing my own also but as you seen it takes quite a bit of work. My mill is a 2003 and the sensor is mounted on the pully of the gearbox instead of the motor. Another thing to make sure if it is on a Woodmizer that the chain on the up/down is tension per service manual.

Ron

Actually, I think I arrived at the same solution.  I have six magnets on the pulley that has spokes.  These little magnets wizz by the sensor and the micro-controller counts the pulses to determine the position of the saw head.  I'm not going to take too much credit here - this is pretty standard fare in the world of industrial control.

I'll defer any saw-mill specific details to my brother - oh Victor!

Shannon

[VictorH]

We'll check that chain tension - Thanks for the tip.

[shaworth]

Thanks for the warm welcome everyone.  

Someone (a moderator?) modified my post and removed the link to the photos on flickr, sigh.

Is there any chance that the forestry forum's photo gallery software supports uploads directly from my android cell phone?  I'll be happy to research this myself if someone in the know can tell me what software powers the photo gallery.  There is hope since the android apps are written in Java, and the upload thingy is also written in Java.  Being a software engineer I'm actually willing to modify the java app to run on the android if that is necessary.

On flicker, and all the other sites I post photos, everything is sent directly from my phone, at the push of a button.  I push a button, check the photos I want to send, and select the sites to send them to.  That simple.  I'm not exactly relishing the thought of downloading my photos from the other sites (all of which provide android apps) to my PC for the sole purpose of uploading them back to Forestry Forum using a PC.  Life is too short to shuffle photos from site to site.  So, please, please help me put this on our phones.

Thanks,

Shannon

[Planman1954]

I use my cellphone and download the photos into My documents-My pictures.

Then I open up my photo gallery, and click on JUPload on the left...This has a program associated with it that downsizes the photo so that it will load fast. Hit the album button and name or select a gallery you've made. Then scroll down and hit browse..and click my documents, my pictures, and then your photo, then hit upload, and then ok.

When you do a post, put your curser where you want the photo, go to your photo gallery by using the forum extras button, click on the photo you want to enter, and then scroll down to the green area, click on it to insert the photo. Then hit preview, and then post.

yeah, nothin' to it, huh. Ha...took me a while.

Planman..

[VictorH]

Here is the link for the gallery
http://www.forestryforum.com/gallery/thumbnails.php?album=2588

[sdunston]

Looks good, I was thinking about a setworks for manual mills, somthing as simple as a read out with a zero set?
Sam

[sgschwend]

Wow, talk about building from scratch! 

Are you going to have the capability to search for the set point?  Do you need to reach the set point from the same direction?

Good work, your brother owes you big, he will need to cut you a house.

[Woodwalker]

shaworth, can you "read" or reference zero at the bed? or do you just read plus or minus from the position of the saw head?
Nice work, I had an old Professor that would have liked the way you are putting it together.

Looks good, I was thinking about a setworks for manual mills, somthing as simple as a read out with a zero set?
Sam

Something like this? (Rotate the picture ninety degrees)



Digital tape, one end clamped to the head the other to the frame. Reads fractions or metric.

[shaworth]

Looks good, I was thinking about a setworks for manual mills, somthing as simple as a read out with a zero set?
Sam

I don't know the first thing about sawmills, so excuse me if my assumptions are wrong.  

By a manual mill, I'm guess you mean the sawhead is raised and lowered using some sort of manual crank.  If not then the rest of this post isn't going to make any sense.  If so, keep reading.

Currently the gadget is programmed to cut off power to the motor (Via a relay) when the set point is reached.  However it would be trivial to modify the programming to count-down to the correct value and flash lights or do something similar when you reach the point.  

If I'm way off base, tell me where I went wrong and I'll try again.

Shannon

[shaworth]

shaworth, can you "read" or reference zero at the bed? or do you just read plus or minus from the position of the saw head?
Nice work, I had an old Professor that would have liked the way you are putting it together.

Looks good, I was thinking about a setworks for manual mills, somthing as simple as a read out with a zero set?
Sam

Something like this? (Rotate the picture ninety degrees)

(Image hidden from quote, click to view.)

Digital tape, one end clamped to the head the other to the frame. Reads fractions or metric.

Man that is elegant.  Currently I measure the relative position of the saw-head.  However I am planning to also measure the absolute distance from the saw bed - soon.  The approach I planned to take is almost like your rather amazing, hack.  Nice work.

The folks that build computer controlled CNC machines use what are essentially long timing belts stretched along their axis of movement.  To this a pulley with a encoder wheel is attached - allowing very precise, wiggle-free position to be maintained.  The next revision...

[shaworth]

I use my cellphone and download the photos into My documents-My pictures.

Then I open up my photo gallery, and click on JUPload on the left...This has a program associated with it that downsizes the photo so that it will load fast. Hit the album button and name or select a gallery you've made. Then scroll down and hit browse..and click my documents, my pictures, and then your photo, then hit upload, and then ok.

When you do a post, put your curser where you want the photo, go to your photo gallery by using the forum extras button, click on the photo you want to enter, and then scroll down to the green area, click on it to insert the photo. Then hit preview, and then post.

yeah, nothin' to it, huh. Ha...took me a while.

Planman..

Thanks for the tips!  I ended up pulling them down, resizing them and uploading them. 

[Woodwalker]

  The next revision...


[/quote]

You may not have a mill, but your hooked.  Keep us posted on any updates.

[pineywoods]

Shannon, thanks for the details. Pretty much like I figured you would do it. Did you program the plc yourself ?
I was considering using one of the old junker laptops I have laying around. That would take care of the inputs and displays, pick up a couple of outputs off the parallel port. A hall effect sensor will trigger the data in pin on the serial port. Probably could get away with programming the whole mess in basic. Quick and dirty 
Now if you really want to get on Victors good side, click here.

http://www.forestryforum.com/board/index.php/topic,33159.msg491067.html#msg491067

 BTW my mill is the same, 95 woodmizer LT40 manual, except it now sports home-made hydraulics.

[shaworth]

Shannon, thanks for the details. Pretty much like I figured you would do it. Did you program the plc yourself ?
I was considering using one of the old junker laptops I have laying around. That would take care of the inputs and displays, pick up a couple of outputs off the parallel port. A hall effect sensor will trigger the data in pin on the serial port. Probably could get away with programming the whole mess in basic. Quick and dirty 
Now if you really want to get on Victors good side, click here.

http://www.forestryforum.com/board/index.php/topic,33159.msg491067.html#msg491067

 BTW my mill is the same, 95 woodmizer LT40 manual, except it now sports home-made hydraulics.

Victor has already mentioned your rig.  As he did the pitch of his voice dropped and he held his gaze real steady-like. 

Yea I coded the software.  I've been programming since the late '70s, so the software side of this project was a breeze for me.  It has been a decade since I programmed a microprocessor and things have gotten a lot more sophisticated on the electronics side.  Most of the time on this project has been spent reading data sheets and re-learning embedded electronics.  Lots of fun, but time consuming.

You seem very pragmatic and I'd like to appeal to that as I preach the embedded micro-processor approach over the clunker laptop approach.  In part because I started this project intending to bring a PC-104 form factor x86 board to the party.  Same thing really.

Cost, a 8bit atmel atmega644 CPU runs about 8 bucks.  This is for a device that cranks out between 8 and 20 million instructions per second.  And is instantly on.  The darn thing is self-contained, flash, eprom, RAM, cpu, pull-up resistors, AD converters, timers ... the whole kitchen sink in a 40 pin chip.  All you need to add is a 5V power supply.  The entire computer is on one chip.

Nearly every pin on this thing (there are 40) is an addressable GPIO.  It is a bit-bangers dream, sans the limitations of the parallel port.

The laptop has a LCD panel illuminated by a florescent tube.  Those tubes tend to go dim over time (as little as 1000 hours).  And they are not that bright to begin with, I can't read mine anywhere near the sun.  Their cold weather performance is embarrassing.

And while I'm using a LCD in my prototype it is illuminated by LCDs, and those suckers don't degrade over time.  But best of all, if I need to I can switch over to LEDs and the design will work in Alaska.

Don't get me started about the keyboard - I'll go with arcade buttons for durability any day.

But the biggest drawback of a laptop is it's complexity.  There are too many points of failure for my tastes.  Plus, unless you enjoy reflow sodering of smd packages, forget about repairing it.  It isn't going to be too keen about the rain and the snow either.

A simple little micro-processor has darn little to break.  Most of the parts (the power supply and RS232 ports really) can be de-soldered and replaced using a $10 iron and a $2 part over the internet.

Now back to that parallel port for a moment.  It reeks of "I like what I know, and I know what I like".  To be honest the atmel CPUs may only be 8 bit devices, but they program and behave a lot like the bad old days of DOS in Intel x86.  The compiler, linker, assembler - the entire tool-chain is open source (read free).  You program the darn things in ANSI (mostly) 'C' and the function library is refreshingly succinct.  Once you finish programming, you hook up your "ISP Programmer", attach it the CPU and run something called "avrdude".  A few seconds later the micro-controller restarts and is running your code.  The only tool that you have to spend money on is the ISP programmer.  I spent $15 on mine.

There is a BASIC compiler (I think it is a C cross-compiler under the hood).  However I'm using and am very happy with the free winavr which is a C compiler.  Atmel gives away their development IDE, avrstudio also.  So you are not stuck with one tool chain.

On, and it borders on being mean to bring this up.  But according to my brother ... that parallel port is going to need either a transistor amp, or better yet a darlington array.  It can't sink enough current to trip and hold a sufficient relay.  You are going to end up with a custom circuit board anyway.  In for a dime, in for a dollar 

But I digress...    Your saw mod is impressive to say the least.  Although I'm still slack jawed by the simplicity of the digital tape measure. 

During the build, you didn't happen to note the current draw for each of the electric motors?  We called WM and were told the saw-head up/down motor requires 60A - which seems silly.  I only ask because my brother has started to make noise about having his own remote operator's console.  I think I'm going to have to order a few more relays and a wireless data link.

Regards,

Shannon

[beenthere]

Shannon
That was an interesting read, and makes me want to scratch an itch when reminded of the 70's and being involved in the new digital (and analog) control design and build (then testing to locate the problems in the design layout or the failure of a chip to do its job). Then out with the solder wick and put in a new chip, etc., etc. Things were big those days compared to the mini-chips now.