Caner, I had a similar situation with my servo amps and I found out that my system was a cascaded position-velocity loop. I suspect that is what yours is too. That means that my external amp, which closes a velocity loop, is nested inside of EMC2, which closes a position loop. For your Toshiba VLASX-012P2 using Mode 1 Analog Input will make it a velocity amplifier using PI (proportional / integral) and will make EMC2 a position controller using only P with FF1 and FF2. No I or D terms are used in the *.ini file. Your amplifiers have Auto-Tuning right? With EMC2 disconnected, I would suggest first tuning the Toshiba to be as stiff as possible. Then connect your analog input. Use Halscope to view your commanded velocity profile compared to your actual output, and use Calibration to slowly increase only your P while jogging at maximum velocity. Use FF1 and FF2 to make the two profiles match as close as possible. The secret to having no oscillations is to have the bandwidth of the velocity loop be greater than or equal to the bandwidth of the position loop. It sounds like right now you have the opposite. Be safe, and good luck.
Jim -----Original Message----- From: Caner [mailto:[email protected]] Sent: Friday, October 29, 2010 2:29 AM To: emc-users Subject: [Emc-users] Two control loop (EMC and Servo Driver)? Hi, I am trying to test my Mesa boards (5i23 and 7i33) with my servo motors. But there is an unexpected problem that EMC2 can't control servo. When I jog, servo motor tuns with oscillation and when i stop jogging, it continue oscillation some seconds more then stop. My servo motor has resolver with 24000ppr and i am getting differential encoder output from its driver. Also servo driver has own control loop inside, i have tried to disable its control loop but i could only set "target loop gain" to 1. Also i have tried to change PID values of EMC2. My servo period is recommended (1000000ns), and PWM/PDM frequency is recommended (100000 Hz). Following Error is 0.5, and Minimum Error is 0.01. I don't know why it happens but i guess two control loop is overlapping. Do you have any idea about my this problem? Am i using too slow servo-thread? Did anyone have tried to use Toshiba Servo Driver (VLASX-012P2) with EMC2? Thanks. --- Caner Durmusoglu ------------------------------------------------------------------------------ Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users This communication is for the use of the intended recipient only. It may contain information that is privileged and confidential. If you are not the intended recipient of this communication, the disclosure, copying, distribution or use hereof is prohibited. If you have received this communication in error, please advise me by return e-mail or by telephone and then delete it immediately. ------------------------------------------------------------------------------ Nokia and AT&T present the 2010 Calling All Innovators-North America contest Create new apps & games for the Nokia N8 for consumers in U.S. and Canada $10 million total in prizes - $4M cash, 500 devices, nearly $6M in marketing Develop with Nokia Qt SDK, Web Runtime, or Java and Publish to Ovi Store http://p.sf.net/sfu/nokia-dev2dev _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
