i wanted to make a patch to drive stepper motors with pd but
run into a serious limitation,i need to run in microseconds
and pd can only run at a milisecond time grain.
what is the way around this?
are any of you guys running stepper motors
with pd, without any other programs? or do you
have to by force use another program?
thanks
r.y
hello,
Le 11/08/2016 à 22:21, ray Y a écrit :
i wanted to make a patch to drive stepper motors with pd but
run into a serious limitation,i need to run in microseconds
and pd can only run at a milisecond time grain.
the audio is more accurate.
what is the way around this?
are any of you guys running stepper motors
with pd, without any other programs? or do you
have to by force use another program?
I supose you use a driver (like pololu or easydriver) to control the steper. You can use your soundcard and a small electronic circuit to get you computer control this hardware.
or you can also use another electronic device (like an arduino) that receive velocity command (that are not update at high speed) from pd and convert it to clock tick to control the steper driver.
cheers c
thanks
r.y
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Pd can also run below 1 millisecond time grain. Try with [metro 0.1] or [delay 0.1] to work with 1/10 of millisecond. ++
Jack
Le 11/08/2016 à 22:21, ray Y a écrit :
i wanted to make a patch to drive stepper motors with pd but
run into a serious limitation,i need to run in microseconds
and pd can only run at a milisecond time grain.
what is the way around this?
are any of you guys running stepper motors
with pd, without any other programs? or do you
have to by force use another program?
thanks
r.y
Pd-list@lists.iem.at mailing list UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list
this is not accurate. see attachment. cheers C
Le 11/08/2016 à 22:52, Jack a écrit :
Pd can also run below 1 millisecond time grain. Try with [metro 0.1] or [delay 0.1] to work with 1/10 of millisecond. ++
Jack
Le 11/08/2016 à 22:21, ray Y a écrit :
i wanted to make a patch to drive stepper motors with pd but
run into a serious limitation,i need to run in microseconds
and pd can only run at a milisecond time grain.
what is the way around this?
are any of you guys running stepper motors
with pd, without any other programs? or do you
have to by force use another program?
thanks
r.y
Pd-list@lists.iem.at mailing list UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list
Pd-list@lists.iem.at mailing list UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list
Yes, absolutely true, it was just to be clear that Pd can run below the millisecond. It was not a solution for the original problem (physical computing with stepper motors). ++
Jack
Le 12/08/2016 à 09:43, cyrille henry a écrit :
this is not accurate. see attachment. cheers C
Le 11/08/2016 à 22:52, Jack a écrit :
Pd can also run below 1 millisecond time grain. Try with [metro 0.1] or [delay 0.1] to work with 1/10 of millisecond. ++
Jack
Le 11/08/2016 à 22:21, ray Y a écrit :
i wanted to make a patch to drive stepper motors with pd but
run into a serious limitation,i need to run in microseconds
and pd can only run at a milisecond time grain.
what is the way around this?
are any of you guys running stepper motors
with pd, without any other programs? or do you
have to by force use another program?
thanks
r.y
Pd-list@lists.iem.at mailing list UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list
Pd-list@lists.iem.at mailing list UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list
On Fri, 2016-08-12 at 10:59 +0200, Jack wrote:
Yes, absolutely true,
I'd rather say somewhat true.
it was just to be clear that Pd can run below the millisecond. It was not a solution for the original problem (physical computing with stepper motors).
If you generate the stepper motor control signal as audio signal that is output through [dac~], you'd gain enough precision. Maybe you can even use an audio amplifier for controlling the the single wires of the stepper motor? (I didn't try myself and am not sure whether it works, I have to say)
Roman
On 08/12/2016 09:43 AM, cyrille henry wrote:
this is not accurate. see attachment.
depends... you really have the same jitter when doing signal processing, and yet you don't hear it. (just hook your [metro 0.1] to a [tgl] -> [vline~] -> [dac~])
why? because [dac~]/[adc~] synchronize the jittery input data with a real-time clock.
so Pd itself is accurate enough. the problem is that you cannot really hook a number box to your stepper motor, you need some object that translates the in-patch messages to real-world events. and this object needs to properly handle the timed messages.
since ray did not mention how he gets the data to the stepper motor, there is little additional help I can give.
gfmdsr IOhannes
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cyrille henry -
IOhannes m zmölnig -
Jack -
ray Y -
Roman Haefeli