Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
Hi Howard You're right of course. My fault for reading the schematics and not the words. Forward and reverse pulses are available for essentially open loop moves. These are available using EMC2 and a parallel port bu I'm with others that this is a poor substitute for real closed loop servo systems. As long as you spend the money for this quality of drive you should take advantage of it's abilities by sending it velocity commands from EMC rather than descrete steps. Rayh --- [EMAIL PROTECTED] wrote: From: Howard Chan [EMAIL PROTECTED] To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'? Date: Fri, 14 Mar 2008 00:06:03 +0800 ... Rayh said that EMC2 and Sanyo servo amp support step and direction. I try to find this method in the Sanyo manual and HAL handbook but I am not sure is it correct. - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
Dear All, I am very happy, you propose some practical suggestions. I and my members take a meeting and decide that we will buy 5I20 control card and 7I33 analog servo amp interface. But there are problems, I would like to ask. Rayh said that EMC2 and Sanyo servo amp support step and direction. I try to find this method in the Sanyo manual and HAL handbook but I am not sure is it correct. In page 45(3-13) of the Sanyo manual, it tells me that there are three types of command input pulse, Positive + Reverse pulse, Code + pulse train and 90 deg phase difference. In page 123(7-10), it shows me more detail information about them. I think that is it only “Code + pulse train” can be supported in the EMC2. If I want to use it type, should I buy 5I20 and 7I37 (Isolated Anything – IO adapter)? In the 7I37 manual, MOSFET outputs turn on in 2 uSec and off in 5 uSec but in the Sanyo manual page 123(7-10), the response time need at least or equal to 0.1 uSec. It means that 7I37 is not suitable this servo amp? At last, according to their experience to create the machine and configure the EMC2, would you mind giving me some hits which thing we should be take care. Thank you very much. Best regards, Howard 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
Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
On Fri, 14 Mar 2008, Howard Chan wrote: Date: Fri, 14 Mar 2008 01:15:01 +0800 From: Howard Chan [EMAIL PROTECTED] Reply-To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net To: Enhanced Machine Controller (EMC) emc-users@lists.sourceforge.net Subject: Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'? Dear Peter, Would you explain detailed about why using the analog velocity input is better then pules/direction? Thank you!! Howard Step and direction interfaces are usually used for simple systems without a fully closed position loop (like step motor systems). While its theoretically possible to use the encoder feedback with step and direction, its not as direct as velocity or torque drive. Another disadvantage of step direction drives is that now you have two feedback PID loops to tune, the amplifiers PID loop and EMCs PID loop. My personal experience is that having the control locus in one place makes tuning easier. Also with step and direction servo amplifiers its likely you would need hardware step generation to reach the full speed capabilities of the drives. In addition you may need two separate operating systems to tune the system, typically Windows to tune the amplifiers PID loop and Linux of course for tuning EMCs PID loops. One general advantage of using EMC for the total control loop (as you would do using the amplifiers torque input and EMC for the PID loop), is that now all of the motion control code is open and changeable. This may be especially important as this is a university project. (no 'black boxes'!) Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your ()_() signature to help him gain world domination. - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
Howard, There is another way... the Sanyo amp and the 5i20/7i33 can work together with analog velocity mode. Emc would work with the 5i20 to create a PWM signal The 5i20 would send this to the 7i33 which would convert PWM to Analog The analog signal would go to the Sanyo amplifier This input is not a pulse at all, it is often a ramp like this V ^__ V ^ e | / \_ o | l | ___/ \__ l | o | t c - time a ig te y the speed is proportional to the command voltage the direction depends on the sign of the command voltage like this __^ / \ | positive direction no motion ___/\...0volts | \ | - time \ | negative direction v The amplifier would move the motor The Encoder would return to the amplifier and on to EMC. EMC would close the position loop. I think this is the most common form of cnc control. It is not the newest, but is very common. regards TomP - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
WE Chan, The amplifier shown on Page 12 can be used in Speed mode on CN1 pins 21 and 20 (not STEP or PULSE ) EMC2 would command the motion by an additional card ( Mesa 5i20 and 7133 for example) that would generate analog voltages to your amplifier. The 5i20 would actually generate PWM, the 7i33 would translate/integrate the PWM into analog. Your motor would pass the encoder information back to the 7133 and then to EMC2 to close the position loop. regards TomP - This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse012070mrt/direct/01/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
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/vse012070mrt/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/vse012070mrt/direct/01/___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Can EMC2 support any 'AC Servo Motor'?
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
