Machsupport Forum

Mach Discussion => Feature Requests => Topic started by: skmetal7 on June 06, 2010, 06:10:12 PM

Title: New Spindle Output Option
Post by: skmetal7 on June 06, 2010, 06:10:12 PM
Ok so many of us have been looking into brushless motors from the RC industry to drive our high speed spindles. I was thinking, if you guys could implement the control scheme to drive a brushless motor Electronic Speed Control or ESC. What this ESC needs to run is a modified version of a PWM square wave. Its a 1-2ms pulse every 20ms at 5v. So 1-2ms pulse @ 50Hz (0 rpm @ 1ms, full rpm @ 2ms).  

-____-____-____  <---- 1ms   --___--___--___  <---- 2ms

Also have an arming feature built in since some have a safety feature where they need to have the "throttle" at a certain pulse rate ( 1.5ms or whatever) for a second or so when you first turn it on ( just have a box to enter a wait period, and ms pulse length).  So if mach3 reads an m3 command, it will activate a relay, turning on the spindle ESC. I guess this could be tied into the Dwell feature of mach3... not sure...

Right now I getting help programming an arduino to take mach3's normal square wave and convert it to this control scheme.  But if you can do this, this extra electronics won't be needed.
Title: Re: New Spindle Output Option
Post by: David_Web on October 07, 2010, 01:28:24 PM
I second this.
I was just bout to post the same thing as I have been looking at a cheap motor + driver that would work as a spindle.

Been thinking bout using Arduino or rather Teensy to do the same.
btw what bout using Teensy as an IO extender board? Or someone might have thought of that already.
Title: Re: New Spindle Output Option
Post by: DaOne on October 14, 2010, 10:02:23 PM
I was working on this a while back. Basically it took Machs spindle PWM output and converted it from a 1ms (stopped) to 2ms signal (Full speed). This would allow a hobby speed controller to act as a drive for a brush less motor spindle. Then you were able to add a rpm sensor and even use the PID built into mach to set and maintain speed. I was  also adding phase control with 2 relays so you can switch 2 of the 3 wires around and get cw and ccw control. The hardware was a pic micro with lcd to display output. If there is enough interest I will see what I can do to continue finishing it.
Title: Re: New Spindle Output Option
Post by: David_Web on November 05, 2010, 05:58:21 PM
Any update?

skametal7: Did it work out with Arduino?