Thomas Kaiser <c...@...> writes: > > On 10/20/2009 08:05 PM, Kirk Wallace wrote: > > On Mon, 2009-10-19 at 20:25 +0200, Thomas Kaiser wrote: > >> Hey > >> > >> Does anybody on this list use the "UHU Servocontroller" > >> [http://www.uhu-servo.de/]? > >> If so, what are the experience with this? What motors you are using? > >> > >> I am just interested at anything somebody did with this . > >> > >> Thomas > > > > In my opinion, step/direction servo motor controllers are not ideal for > > EMC2, since the motion control (PID) and position feedback is built in > > to EMC2. For servo's, a PWM or analog input driver is better. With this > > kind of driver, you will have access "under the hood", allowing you to > > tune and customize your system through EMC2's HAL. Many step/dir > > controllers only have a separate Windows program for tuning. > > > > UHU is a do-it-your self project, so if you want to build something > > yourself this may help: > > http://www.electronicsam.com/images/KandT/servostart/schem/ > > > > Or you can copy a reference h-bridge design from one of the chip > > manufacturer's data sheets. When you get into the higher power motors, > > you will need to allow for current limit control, FET shoot-through, and > > fly-back currents. Usually, it is better to purchase higher power > > drivers. > > Hello Kirk > > I try to give new life to an old Schaublin lathe. On this lathe the NC > controller died. Everything else seems to be OK. So, I am trying to > replace the old NC controller with EMC, which worked so far for the X-Z > axis > > The old NC controller just sent pulse and direction signals to the > drives. But as far as i can tell, the motors are DC motors with encoders > and look more like servos. These drives are still working and I hooked > up EMC in stepper configuration (parallel port) which works > > My goal is to just replace the NC controller and use as lot as possible > things which are still working. > > I just was thinking what would happen when one of the drives dies (no > spare parts available anymore). It would be handy to replace the dead > drive with something similar, keep the old motor and the "old" stepper > (parport) configuration. I think UHU Servocontroller would be a good > alternative. > > Here is a link from the same machine I am working on. But they replace > everything with a new Siemens control. I will stay with EMC! > > http://www.wfrauenfelder.ch/LAP2005/LAP2005.htm > > The 2 first pictures are with the old controller and drives. > > Thomas > > PS: I am an electronic engineer, so no problem with DIY projects > > ------------------------------------------------------------------------------ Hello again Thomas,
If, as you say, you want to stick with the drives that are currently on the machine, and furthermore if they are already configured to use step and direction and you can control them with EMC in stepper configuration, then just keep on going until something in the drives dies. Then if you do not want to find and fix the smoking part, you could at that time replace the servo drives with any number of new or legacy units that accept the industry standard -10 to +10vdc velocity reference, instead of the UHU controller. This way, you can use any number of available boards from different suppliers who support EMC to generate the necessary velocity command, pass encoder velocity and position info back to EMC, provide I/O pins, etc (I used Mesa Electronics). This way you will have a more tightly integrated system, and you can use the built-in Halscope to tune your servos and tweak you systems performance from within EMC. regards, Tom ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
