On 28 April 2010 17:16, Jon Elson <el...@pico-systems.com> wrote: > > Andy Pugh wrote: >> I just found this application note from Atmel >> http://www.atmel.com/dyn/resources/prod_documents/doc2592.pdf >> > The problem with all of these designs is they have no current loop > control. I could be wrong, but I think you really need closed-loop > current (torque) control for this to work well.
I suspect you are right. For me this is just messing about, the Arduino-based system is a toy project aimed at getting my eBay bargain servos spinning without spending 10x the price of each motor on a drive. (The motors were 3x 400W motors for £50 BiN) Each motor needs £34 of connectors to even wire it up, if I ever do the job right. I don't even have an application for these motors, my CNC machine is perfectly functional with the NEMA23 steppers. But, while I am playing around, would a 74HC244 (tristate octal buffer) be a neater solution than the OR gate in the application note? It seems to me that I could wire the master PWM to the Output-Enable pins and the driver signals through the data lines. The main reason I ask is that I have a whole tube of the buffers going spare. -- atp ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
