Hi Howard Glad to hear of your interest in EMC2. It is a great system for students because it will allow you to experiment with most motion control variables.
The pdf at the link you posted includes a lot of sales pitch. It appears to have been written and edited by someone with limited motion control experience. They have very successfully blended together at least three input signal types to maximize the apparent value of their products. You will need to sort out most all of it to get the system that will work for you. Sanyo lists three kinds of motion signals. They include analog voltage, step and direction, and CANopen. EMC2 as it exists right now can handle two of these, analog voltage, and step and direction. We do NOT have serial drivers in our motion software that would permit CANopen control. Hint -- Serial communication using CANopen would be an excellent graduate student project. I'll expand just a bit on the two systems we do have for your use right now. It looks like Step and Direction signals can be used with both the stand alone amps and with the multi axis package. EMC2 produces millions of step and direction signals every day. They are the preferred motion signal for stepper motor powered systems. What this drive does is make the servo motor look like a stepper motor if you use this control signal. You will have a real advantage over steppers because the motor's torque will not fall off as speed increases but you will still see some cogging at low speeds. There may also be an upper RPM limit, well below the max speed of the motors unless the drive includes a pulse multiplier or you add an external hardware work around. Permit me to do a bit of computation on this max rotational velocity using step signals. If the supplied encoder is 2500 pulses per rev, and the amp equates external steps one-to-one then you will need 2500 pulses for each revolution. Let's imagine that your computer can supply 30k pulses per second (PPS) using the EMC2. That combination will allow 12 revolutions per second or 720 RPM. What is the maximum pulse speed you can expect from EMC2. Alex and I were is a bit of a contest a while back and were able to get pulse speeds of 75 to 90 thousand pulses per second. It may be that we could get even faster speeds now that Jeff has added his rate doubler. You can see that rotational speed is still somewhat limited. At 90k PPS you would be limited to about 2100 RPM. The second type of speed signal that EMC2 can offer is an analog signal. This could be pulse width or -10 tp +10 volt using a PC card like Alex and Tom suggested. These analog signals have the advantage of driving the motor to full speed and to constant velocity at low speeds. Analog has the advantage of producing a real, closed loop servo system. I would use this system even though it costs the price of an extra computer board and requires a bit more care in wiring. If you choose analog signals you must make certain the amps you purchase allow you to connect those signals. Not all of the amps listed do that. It looks like, although the pdf does not say so, that you will need to use a Microsoft OS to tune the amps. Writing a Linux/EMC2 based tuning software for these drives would also be a valuable student project, if your school and discipline includes both hardware and code writing. Good luck and welcome. Rayh --- [EMAIL PROTECTED] wrote: From: "Alex Joni" <[EMAIL PROTECTED]> To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Subject: Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'? Date: Wed, 12 Mar 2008 13:57:00 +0200 Hello, for what you want to accomplish you need a special motion control board. A list with supported hardware by emc2 can be found at: http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?EMC2_Supported_Hardware Best regards, Alex ----- Original Message ----- From: WF Chan To: emc-users@lists.sourceforge.net Sent: Wednesday, March 12, 2008 1:15 PM Subject: [Emc-users] Can EMC2 support any 'AC Servo Motor'? Dear All, I am a student. I will use a open platform system to control three axis AC Servo motors in my final year project(FYP). I searched a EMC2 in the internet. It is base of the linux OS, it supports maximum 9 axis (very powerful), GM code and graphics mode. It is very suitable for me to do my FYP. I have questions to ask all people: 1. I must use AC Servo motors to do my project and I choose SANMOTION R of SANYO DENKI INC. Below is the user manual: http://www.sanyo-denki.com/Data/Servo/catalogs/R_Ver3.pdf In page 42(3-10), the pin 21 is the input control command which is using speed and torque value. But I found in the HAL Handbook that it only support ‘step pulse’ to do the control. Is it menu that the EMC2 cannot support any AC servo motors?? Are there any people can help me or give me any suggestions how to solve my problem? Thank you very much!! Best regards, Howard Yahoo! 網上安全攻略，教你如何防範黑客! 了解更多 ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. 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