[vacpress]

If you guys do all the preliminary work, I would be interested in creating some\most\all of the 3D models and 2D drawings..

someone else has to build the thing and take the photos and make parts lists and all that. i am busy, but design work can be done quickly, depending on what is involved.

R

[mohaon]

thank you man

[kreutz]

How do you get 3 or 4 PWM phases from a micro-controller or PC? It’s not easy and I personally would not try it unless you have 40MIPs+ to work with.

Attiny2313 @20 Mhz 4 hardware PWM 2 x 8 bits, 2 x 16 bits set and forget, it is not necessary to have a DSP for that.

PWM sinusoidal quadrature voltage waveform generation, as I understand you are suggesting, will make it rotate, but you are forgetting that what is needed to keep a constant torque vs angular position are sinusoidal phase currents 90 degrees apart (for a two phase motor). You are also forgetting you are driving an R-L circuit, and also that, as soon as it begins moving there is BEMF present. One thing is moving the motor, a completely different one is getting accurate positioning. An stepper motor will behave like a synchronous AC motor, but you need to drive it the right way.

[shashank ayyar]

if someone could help me out with the plans....

[kreutz]

if someone could help me out with the plans....

There are a lot of simple DIY schematics at http://pminmo.com/, Pminmo has also a very good wiki with a lot of information about the electronic part of CNC.

There are a couple of a little more complicated designs for high power unipolar motors (up to 80 Volt 8 Amperes) here on the zone:

http://www.cnczone.com/forums/showthread.php?t=25361 and http://www.cnczone.com/forums/showthread.php?t=38873

and some videos of them in action: http://www.youtube.com/results?searc...&search=Search

For high power bipolar controllers I always suggest Gecko's.

[shashank ayyar]

There are a lot of simple DIY schematics at http://pminmo.com/, Pminmo has also a very good wiki with a lot of information about the electronic part of CNC.

There are a couple of a little more complicated designs for high power unipolar motors (up to 80 Volt 8 Amperes) here on the zone:

http://www.cnczone.com/forums/showthread.php?t=25361 and http://www.cnczone.com/forums/showthread.php?t=38873

and some videos of them in action: http://www.youtube.com/results?searc...&search=Search

For high power bipolar controllers I always suggest Gecko's.

you guys are unbelievably helpful.

[pminmo]

Maybe this will help: http://www.pminmo.com/wiki/index.php...ystem_Overview

[frog]

I have an idea, and looks like the most logical place to post it. I am thinking about starting a Co-Op group online maybe a thread, you see I am a College instructor. As a hobby I have a machine shop for fun. 2 CNC machines, one just purchased. I have noticed that everyone wants to have the chance to build their own machines, here is what I am proposing. That we form a group online and all work together and meet once a week and start with a base machine, we can modify size to suit our own needs, then once we have agreed upon a design I will build a 3D version in Bob Cad, then we can modify it to suit our needs. Ok here is the cool part if you are in the design group that we can form I have a friend that is a Retired Tool and Die maker from IBM and he tinkers in the Machine shop, We can have him make the parts at cost plus a little for lunch. I am thinking 6160 Rolled or Extruded Have him do the machine work based on our plans, here is the catch the parts will have to be standard, that way he can make multiple sets. I would like to try this as a group. However initially in order to get a set of plates at a cost effective price you would have to be in on the design process. This is a great opportunity for a bunch of people to put their heads together and come up with a working product. We can meet online using Grove or Net meeting. Then determine who is responsible for what part of the design. Then come back and post our findings in the thread. I have some wonderful Ideas for designing a Unipolar controller, as if we need another. Next we can make up specs as well as design deadlines. Here is a chance to experience a real life Product Development Cycle. IT WILL BE OPEN SOURCE ONLY. So everyone when it is finished it will be posted so anyone in any machine shop could build it. The First Version 3 AXIS Second Version 4 next version 5 Axis. Ect. This is an ambitious project. Email me [email protected] or post back in this thread. I have designed and built a few machines as well as the electronics. I have also written some interface software, for machine control. This is just a hobby so it will have to go at a hobby pace, for the parts. Feedback is appreciated.