Dynomotion

Group: DynoMotion Message: 8099 From: easydigisoft Date: 8/15/2013
Subject: Need help with jog speed and few other thinks
Hi.

First of all great job on the product it works good.

I have few questions.
1. Why when I execute DisableAxis(0) in C code my axis is slowly rotating? When I hit init it stops but when click STOP it always slowly moves. I measured the output voltage on the channels and on all DAC outputs there are like 3 to 6 mV voltage. I guess because of that voltage the axis is slowly moving.
How can I fix that? Is that normal?

2. In KmotionCNC there are jog buttons but they are constant speed. I tried changging the FDO trackbar (feedrate) but the jog buttons are moving the same speed. How can I make them go slower or faster like on real CNC there is x10, x100, x1000.

Thanks.
Group: DynoMotion Message: 8100 From: Tom Kerekes Date: 8/15/2013
Subject: Re: Need help with jog speed and few other thinks
Hi easydigisoft,

Regarding:

#1 - drift is a common problem when the servo is disabled.  It is difficult to command exactly zero velocity with an analog signal that will always have some offset and noise.  The solution is to disable the amplifier whenever the KFLOP Axis channel is disabled.   You will need a bit of C code to do this.  See the watchenable.c example.

#2 - With the KMotionCNC Jog buttons there are two speeds.  The slow/fast ratio used to be fixed at 50%.  The latest code allows you to set the ratio to whatever you would like on the Tool Setup | Trajectory Planner Screen. The best solution is to add an MPG Pendant with a X1, X10, X100, X1000 switch.

Regards
TK 

Group: DynoMotion Message: 8101 From: easydigisoft Date: 8/15/2013
Subject: Re: Need help with jog speed and few other thinks
Thanks for the great respond.
I have MPG and it only has (+5V GND A B) how can I connect this A and B signals and to what ports on the kanalog?
Thank you very much.

--- In DynoMotion@yahoogroups.com, Tom Kerekes <tk@...> wrote:
>
> Hi easydigisoft,
>
> Regarding:
>
> #1 - drift is a common problem when the servo is disabled.  It is difficult to command exactly zero velocity with an analog signal that will always have some offset and noise.  The solution is to disable the amplifier whenever the KFLOP Axis channel is disabled.   You will need a bit of C code to do this.  See the watchenable.c example.
>
> #2 - With the KMotionCNC Jog buttons there are two speeds.  The slow/fast ratio used to be fixed at 50%.  The latest code allows you to set the ratio to whatever you would like on the Tool Setup | Trajectory Planner Screen. The best solution is to add an MPG Pendant with a X1, X10, X100, X1000 switch.
>
> Regards
> TK 
>
>
> ________________________________
> From: easydigisoft <easydigisoft@...>
> To: DynoMotion@yahoogroups.com
> Sent: Thursday, August 15, 2013 10:55 AM
> Subject: [DynoMotion] Need help with jog speed and few other thinks
>
>
>
>  
> Hi.
>
> First of all great job on the product it works good.
>
> I have few questions.
> 1. Why when I execute DisableAxis(0) in C code my axis is slowly rotating? When I hit init it stops but when click STOP it always slowly moves. I measured the output voltage on the channels and on all DAC outputs there are like 3 to 6 mV voltage. I guess because of that voltage the axis is slowly moving.
> How can I fix that? Is that normal?
>
> 2. In KmotionCNC there are jog buttons but they are constant speed. I tried changging the FDO trackbar (feedrate) but the jog buttons are moving the same speed. How can I make them go slower or faster like on real CNC there is x10, x100, x1000.
>
> Thanks.
>
Group: DynoMotion Message: 8103 From: easydigisoft Date: 8/15/2013
Subject: Re: Need help with jog speed and few other thinks
Can you tell me what is #define MPG_INPUT_AXIS 6 ?
I am trying to make this work MPG. It has +5V GND A B. I connected A to A+ and B to B+ on channel3 from kanalog. I live A- and B- unconnected is this ok or should I ground them?

What example should I use MPGSmoothHardwareEnc.c or MPGSmooth.c. What is the difference?

I use Servo motors with encoders connected to ch0, ch1 and ch2.

Thanks.

--- In DynoMotion@yahoogroups.com, Tom Kerekes <tk@...> wrote:
>
> Hi easydigisoft,
>
> Regarding:
>
> #1 - drift is a common problem when the servo is disabled.  It is difficult to command exactly zero velocity with an analog signal that will always have some offset and noise.  The solution is to disable the amplifier whenever the KFLOP Axis channel is disabled.   You will need a bit of C code to do this.  See the watchenable.c example.
>
> #2 - With the KMotionCNC Jog buttons there are two speeds.  The slow/fast ratio used to be fixed at 50%.  The latest code allows you to set the ratio to whatever you would like on the Tool Setup | Trajectory Planner Screen. The best solution is to add an MPG Pendant with a X1, X10, X100, X1000 switch.
>
> Regards
> TK 
>
>
> ________________________________
> From: easydigisoft <easydigisoft@...>
> To: DynoMotion@yahoogroups.com
> Sent: Thursday, August 15, 2013 10:55 AM
> Subject: [DynoMotion] Need help with jog speed and few other thinks
>
>
>
>  
> Hi.
>
> First of all great job on the product it works good.
>
> I have few questions.
> 1. Why when I execute DisableAxis(0) in C code my axis is slowly rotating? When I hit init it stops but when click STOP it always slowly moves. I measured the output voltage on the channels and on all DAC outputs there are like 3 to 6 mV voltage. I guess because of that voltage the axis is slowly moving.
> How can I fix that? Is that normal?
>
> 2. In KmotionCNC there are jog buttons but they are constant speed. I tried changging the FDO trackbar (feedrate) but the jog buttons are moving the same speed. How can I make them go slower or faster like on real CNC there is x10, x100, x1000.
>
> Thanks.
>
Group: DynoMotion Message: 8104 From: Tom Kerekes Date: 8/15/2013
Subject: Re: Need help with jog speed and few other thinks

Hi easydigisoft,

That encoder only has single ended signals that can not be connected to Kanalog's differential inputs.  You can not just leave the - inputs floating or grounded.

They can be connected directly to KFLOP single ended inputs.  See also:

http://dynomotion.com/faq.html#Encoders

It seems you are not using Kanalog JP2 differential inputs.  In this case you can unplug KFLOP JP5 going o Kanalog and feed in single ended encoder signals into KFLOP there.

Regarding MPGSmoothHardwareEnc.c or MPGSmooth.c : there are two techniques for counting an encoder input.  #1 you can use a hardware encoder input.  or #2 count the pulses with software.  The advantage of using a hardware input is that it can handle count rates to 1 MHz.  Where software can not handle very high rates (software loops usually execute at ~5KHz but we use a trick which assumes the speed can't change instantly to extend the rate a few times higher, this is usually adequate for a hand rotated MPG encoder).  The disadvantage with using a hardware encoder input is that there are a limited number available, fixed pins must be used, and an Axis Channel must be used to read and maintain the accumulated encoder Position.  MPG_INPUT_AXIS defines which KFLOP Axis Channel will be configured and used to maintain the encoder reading.

HTH
Regards
TK
Group: DynoMotion Message: 8106 From: easydigisoft Date: 8/16/2013
Subject: Re: Need help with jog speed and few other thinks
It seems you are not using Kanalog JP2 differential inputs. In this case you can unplug KFLOP JP5 going o Kanalog and feed in single ended encoder signals into KFLOP there.

If I do that then how can I write C code like channel? Then it won't be channel? I should loop in init and wait for the A B signals?

--- In DynoMotion@yahoogroups.com, Tom Kerekes <tk@...> wrote:
>
>
> Hi easydigisoft,
>
> That encoder only has single ended signals that can not be connected to
> Kanalog's differential inputs.  You can not just leave the - inputs floating or grounded.
>
> They can be connected directly to
> KFLOP single ended inputs.  See also:
>
> http://dynomotion.com/faq.html#Encoders
>
> It seems you are not using Kanalog JP2 differential inputs.  In this case you can unplug KFLOP JP5 going o Kanalog and feed in single ended encoder signals into KFLOP there.
>
>
> RegardingMPGSmoothHardwareEnc.c or MPGSmooth.c : there are two techniques for counting an encoder input.  #1 you can use a hardware encoder input.  or #2 count the pulses with software.  The advantage of using a hardware input is that it can handle count rates to 1 MHz.  Where software can not handle very high rates (software loops usually execute at ~5KHz but we use a trick which assumes the speed can't change instantly to extend the rate a few times higher, this is usually adequate for a hand rotated MPG encoder).  The disadvantage with using a hardware encoder input is that there are a limited number available, fixed pins must be used, and an Axis Channel must be used to read and maintain the accumulated encoder Position.  MPG_INPUT_AXIS defines which KFLOP Axis Channel will be configured and used to maintain the encoder reading.
>
>
> HTH
> Regards
> TK
>
>
> ________________________________
> From: easydigisoft <easydigisoft@...>
> To: DynoMotion@yahoogroups.com
> Sent: Thursday, August 15, 2013 3:00 PM
> Subject: [DynoMotion] Re: Need help with jog speed and few other thinks
>
>
>
>  
> Can you tell me what is #define MPG_INPUT_AXIS 6 ?
> I am trying to make this work MPG. It has +5V GND A B. I connected A to A+ and B to B+ on channel3 from kanalog. I live A- and B- unconnected is this ok or should I ground them?
>
> What example should I use MPGSmoothHardwareEnc.c or MPGSmooth.c. What is the difference?
>
> I use Servo motors with encoders connected to ch0, ch1 and ch2.
>
> Thanks.
>
> --- In DynoMotion@yahoogroups.com, Tom Kerekes <tk@> wrote:
> >
> > Hi easydigisoft,
> >
> > Regarding:
> >
> > #1 - drift is a common problem when the servo is disabled.  It is difficult to command exactly zero velocity with an analog signal that will always have some offset and noise.  The solution is to disable the amplifier whenever the KFLOP Axis channel is disabled.   You will need a bit of C code to do this.  See the watchenable.c example.
> >
> > #2 - With the KMotionCNC Jog buttons there are two speeds.  The slow/fast ratio used to be fixed at 50%.  The latest code allows you to set the ratio to whatever you would like on the Tool Setup | Trajectory Planner Screen. The best solution is to add an MPG Pendant with a X1, X10, X100, X1000 switch.
> >
> > Regards
> > TK 
> >
> >
> > ________________________________
> > From: easydigisoft <easydigisoft@>
> > To: DynoMotion@yahoogroups.com
> > Sent: Thursday, August 15, 2013 10:55 AM
> > Subject: [DynoMotion] Need help with jog speed and few other thinks
> >
> >
> >
> >  
> > Hi.
> >
> > First of all great job on the product it works good.
> >
> > I have few questions.
> > 1. Why when I execute DisableAxis(0) in C code my axis is slowly rotating? When I hit init it stops but when click STOP it always slowly moves. I measured the output voltage on the channels and on all DAC outputs there are like 3 to 6 mV voltage. I guess because of that voltage the axis is slowly moving.
> > How can I fix that? Is that normal?
> >
> > 2. In KmotionCNC there are jog buttons but they are constant speed. I tried changging the FDO trackbar (feedrate) but the jog buttons are moving the same speed. How can I make them go slower or faster like on real CNC there is x10, x100, x1000.
> >
> > Thanks.
> >
>
Group: DynoMotion Message: 8108 From: easydigisoft Date: 8/16/2013
Subject: Re: Need help with jog speed and few other thinks
What about homing?
If I use home switch then this method is not ideal. Every time when I home the machine it will be different position because switch is not ideal. Should I use the switch for homing and then use servo encoder index to position on the index?

For example I home the machine and start working on something. Then I turn of the machine and in the morning I would like to continue. What will happen? Will I lose the center? Should I home the machine again?

Can you explain me a little about this? Thank you.

--- In DynoMotion@yahoogroups.com, Tom Kerekes <tk@...> wrote:
>
>
> Hi easydigisoft,
>
> That encoder only has single ended signals that can not be connected to
> Kanalog's differential inputs.  You can not just leave the - inputs floating or grounded.
>
> They can be connected directly to
> KFLOP single ended inputs.  See also:
>
> http://dynomotion.com/faq.html#Encoders
>
> It seems you are not using Kanalog JP2 differential inputs.  In this case you can unplug KFLOP JP5 going o Kanalog and feed in single ended encoder signals into KFLOP there.
>
>
> RegardingMPGSmoothHardwareEnc.c or MPGSmooth.c : there are two techniques for counting an encoder input.  #1 you can use a hardware encoder input.  or #2 count the pulses with software.  The advantage of using a hardware input is that it can handle count rates to 1 MHz.  Where software can not handle very high rates (software loops usually execute at ~5KHz but we use a trick which assumes the speed can't change instantly to extend the rate a few times higher, this is usually adequate for a hand rotated MPG encoder).  The disadvantage with using a hardware encoder input is that there are a limited number available, fixed pins must be used, and an Axis Channel must be used to read and maintain the accumulated encoder Position.  MPG_INPUT_AXIS defines which KFLOP Axis Channel will be configured and used to maintain the encoder reading.
>
>
> HTH
> Regards
> TK
>
>
> ________________________________
> From: easydigisoft <easydigisoft@...>
> To: DynoMotion@yahoogroups.com
> Sent: Thursday, August 15, 2013 3:00 PM
> Subject: [DynoMotion] Re: Need help with jog speed and few other thinks
>
>
>
>  
> Can you tell me what is #define MPG_INPUT_AXIS 6 ?
> I am trying to make this work MPG. It has +5V GND A B. I connected A to A+ and B to B+ on channel3 from kanalog. I live A- and B- unconnected is this ok or should I ground them?
>
> What example should I use MPGSmoothHardwareEnc.c or MPGSmooth.c. What is the difference?
>
> I use Servo motors with encoders connected to ch0, ch1 and ch2.
>
> Thanks.
>
> --- In DynoMotion@yahoogroups.com, Tom Kerekes <tk@> wrote:
> >
> > Hi easydigisoft,
> >
> > Regarding:
> >
> > #1 - drift is a common problem when the servo is disabled.  It is difficult to command exactly zero velocity with an analog signal that will always have some offset and noise.  The solution is to disable the amplifier whenever the KFLOP Axis channel is disabled.   You will need a bit of C code to do this.  See the watchenable.c example.
> >
> > #2 - With the KMotionCNC Jog buttons there are two speeds.  The slow/fast ratio used to be fixed at 50%.  The latest code allows you to set the ratio to whatever you would like on the Tool Setup | Trajectory Planner Screen. The best solution is to add an MPG Pendant with a X1, X10, X100, X1000 switch.
> >
> > Regards
> > TK 
> >
> >
> > ________________________________
> > From: easydigisoft <easydigisoft@>
> > To: DynoMotion@yahoogroups.com
> > Sent: Thursday, August 15, 2013 10:55 AM
> > Subject: [DynoMotion] Need help with jog speed and few other thinks
> >
> >
> >
> >  
> > Hi.
> >
> > First of all great job on the product it works good.
> >
> > I have few questions.
> > 1. Why when I execute DisableAxis(0) in C code my axis is slowly rotating? When I hit init it stops but when click STOP it always slowly moves. I measured the output voltage on the channels and on all DAC outputs there are like 3 to 6 mV voltage. I guess because of that voltage the axis is slowly moving.
> > How can I fix that? Is that normal?
> >
> > 2. In KmotionCNC there are jog buttons but they are constant speed. I tried changging the FDO trackbar (feedrate) but the jog buttons are moving the same speed. How can I make them go slower or faster like on real CNC there is x10, x100, x1000.
> >
> > Thanks.
> >
>
Group: DynoMotion Message: 8113 From: Tom Kerekes Date: 8/16/2013
Subject: Re: Need help with jog speed and few other thinks
Hi easydigisoft,

You should be able to power down your amplifiers without loss of position as long as power remains on to KFLOP and the encoders.  But yes if you lose all power then you will lose position and need to re-home.

You can create a homing program that uses the index pulse on your encoder.  The normal process is to move until an Home Switch is detected and then reverse slowly until the index pulse is detected.  Of course the Index pulse must be wired to some KFLOP input. 

There is an example function that can be included in your Home Program to do this.  See the attached files.

HTH
Regards
TK