[ivancasten]

Yup, no problems, the ones I have cost about $25.00 bucks US and have selectable resolution from 96 to 2048 CPR and work very well.

Greetings Russell,
Could I ask which ones you have?
Cheers Ivan

[epineh]

Sure... :

http://www.digikey.com/scripts/DkSea...me=102-1308-ND

They are actually $29.00 each I can't remember if they were cheaper when I bought them...

They sell a cable that fits the connector on the encoder, it would make life easier, I didn't see it until I finished my version.

Cheers.

Russell.

[ivancasten]

G'day All,
What technique do you use to make PCB's.
eg etching ,routing , commercial.
Cheers Ivan

[krazatchu]

Some of us do toner transfer, some do direct print and some do milling...

Direct print and milling require more equipment and effort for first time pcb making...
Here is a thread for direct print...

I have tried milling but these days I just do toner transfer...
My current focus now is to experiment with EDM to make PCBs without chemicals...
Here is one of the millions of threads about toner transfer...

For your first time, I would recommend toner transfer...
Here is a brief rundown of the process...

1) print artwork with laser printer onto a piece of glossy magazine paper...
2) clean the bare pcb with a scratchy pad, no fingerprints, and dry it ...
3) put the magazine paper on the pcb, apply iron...
4) soak in water to loosen up the magazine paper & remove paper...
5) use FeCl3 or whatever acid you want...

Michael..

[ivancasten]

G'day Michael,
Thanks for your informative reply.
My experience with PCB makeing was "umpteen" years ago.
Consisted of packets of etch resistant transfers and badly discoloured finger nails.
Worked well for large size traces etc.
Cheers Ivan

[zafpcb]

HI ALL
Does any body can help me to give some tested pcb designs foe elm servo.There is mess of discussion but no any tested board and schematic

[epineh]

There may not be many board layouts but the schematics are per the original Elm Chan schematics, they are fairly simple to follow and the design works well.

Here is my design, use at your own risk - I don't document very well and you will have to work out gate driver resistors to suit your needs. I am using a seperate processor board and H Bridge board, think of it as a guide

Also for the guru's out there, I would like to implement a tuning aid, I was thinking of getting the code modified to output the set point and the following error but I just noticed on the original site that an "L" command will output a string of motor position, until another key is pressed, so does this mean we could use this to make graphs as per the usual servo tuning procedures ?

If so what software needs to be made/used to achieve this ? It would make tuning a lot more precise than going by "feel"

Russell.

[epineh]

Well I checked on my drives and the L command is not in the latest firmware, I have gone through it and it will be easy enough to implement, but I am thinking of also having the drive output the commanded position as well, this way the info will be able to be graphed together and should make tuning a breeze.

I have a friend that is willing to make a console app that will be used to both set drive parameters and log the output stream and save it in an XML file, this way the tuning software will possibly be cross platform ie. Linux and Windows. He is going to use C++ so hopefully somebody can do the required changes and make it usable in Linux (not me I am a noob as far as that stuff goes )

So the plan is to make a little Windows app (that can easily be ported to Linux) that will basically be an enhanced hyperterminal (or Gtkterm) program, this will be be able to program the parameters, and at the press of the L button, start logging the commanded position and the actual motor position and log these into a standard XML file that can be opened into a spreadsheet of your choice and graphed from there.

Of course the natural progression from there is an auto-tune function, this would need some extra functionality back into the ELM, mainly the re-install of the native G0 or G1 commands that the smc/3 version firmware ... but I guess one thing at a time.

Russell.

[moraru]

Hi all,

Any progress?

moraru.

[Rony.sn]

Hi,
In the meantime , i changed the X axis from stepper to a elm servo.
But still no high power endstage.
I use the same H bridge as for the steppers ( L6203 ) , with a supply of 40v dc.
Now instead of 250 mm / min , it runs 2 m / min.
An improvement of course .

The logic and the power stage are on 2 separate ( half eurocard ) single sided boards.
Most of the hobby time now , goes to the development of a cnc lathe.
And of coarse it will be servo driven .
So the need for a more powerfull H bridge is still pending.
Though i have an idea in mind , if it works there will be a post here.
The logic part is ok , and a friend of mine made a labview program , to easily set the parameters with a graphical , slide bar, interface.
Grts ,

Rony

[moraru]

Rony,

I build Elm servo CPU, with H-bridge from arisov, cnczone.com/forums/showthread.php?t=69640, and works fain, but I don't can to change servo parameters. Rx works but Tx don't. Reason for this build is transition from stepper motors to servo motors. I have a engraving machine with stepper motors and I don't gratified with this, and I want to change steppers with servo motors.

Rony you can modify parameter?

Tanks,
Moraru.

[Rony.sn]

Moraru,

I will attach my simple shematic for the logic part of the controller.
It is designed with free shematic, this is a free download, program.
No fancy ic's used for the serial communication.
If you have difficulties to communicate with your controller.
First thing to do , is connect RX an TX together at the pc side.
No matter what communication software u use, eg hyper terminal in windows , you should see directly on the pc screen every character you send.
Echo back , i believe this is called.
If this is ok , chek baud rate (38500)and connection to the micro controller.
It just should work.
Grts Rony

[arisov77]

I build Elm servo CPU, with H-bridge from arisov, cnczone.com/forums/showthread.php?t=69640, and works fain, but I don't can to change servo parameters. Rx works but Tx don't.

That concretely beside You was not got? The Reaction on change PID adjustment must be significant. Let's on http://cnczone.com/forums/showthread.php?t=69640&page=2 this shall discuss. Possible this to whom that else is useful.

[alex7street47]

i bet u have try loop test and DID go well..

[atmel]

for the guys who are looking for the eagle files that works with a legal eaglecad version.
You can find them here .
I also noticed the demand for a source of encoder rotating discs,
look at link . Real size is about 55mm diameter.
This can I print with a original photoplotter on film.
if any one wand some just mail or pm me. also your own design of course.

greetings Roel

[moraru]

Hi Roel,

You build this servo?
How work?

Regards Moraru.

[Like2Trike]

I need HELP.

I have a STK500 board I am using for programming with AVR Studio 4. When compiling the original SMC3a hex file I get several warnings but no errors so this could be normal. My problem is I don't know what fuse setting should be used on this programmer since it seems everyone is using a different programming setup and I have never used this one before only Arduino and PIC before. I assume I need to set it for external xtal 8mhz-

Once programmed if I hook it up to a serial port (38400 baud) through the STK500 should I get anything out when it is powered up? I have checked the communication using my Arduino and it works, so my port and everything is fine. I just don't get anything from the servo board.

If I leave the ATTINY2313 on the STK500 without anything hooked up to it but the RS232 and crystal, should this send out data to the terminal?

Solution found, I didn't have the fuses set right now to test the amplifier section

[Like2Trike]

I was wondering if anyone had put the L and G functions back in the code. I would like to be able to use that if it was available. I have the SMC3a version working, it was quite a trick tuning the system. I am running very small servo motor at low voltages so it took a while to figure it out. I'd like to thank all the contributors without you I would still be beating my head against the wall.

[abc_santosh]

i change xtal 16Mhz and use original of smc3a.asm and the problem still just like the previous post. Any suggestion ?????????

btw : led indicator is green.

Hai all,
I have problem almost like tady.

Hyperterminal (38400,8,parity none,1,none) can't display SMC3A-Servo Motor controller(?:help) and can't type any thing on screen


Hi all, My problem is same as roberto. What did you do to correct it?

I am also getting strange characters in hyper terminal. Help me.

[Like2Trike]

Problem with using a 16MHz crystal is the baud rate is wrong for communication with hyperterminal. You have a baud rate of 30720 and that wont work.