Stepper motor problem

[f.ducret@sussex.ac.uk]

Hi!
I edited a code with labview to control the motion of my stepper motors
by simply sending a command to the serial port 1, this command depends
on the controller card.
It works absolutely fine but when the code is running for long, the
stepper motor goes funny and doesn't stop , I have to switch off the
controller card power supply resulting in the lost of the reference
point I have previously set up.
It might be the buffer memory getting full, I tried to initialise the
port without any success, it still does it.
It is crucial for me to solve this, the stepper motors are used to
transverse optics such as lens and mirror. If this happens again the
optics could be crunched.
Thanks

Fabrice


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Be
fore you buy.

[Jim_Kring]

Stepper motors can get stuck and resonate if they are driven at too high as
frequency or if they are overloaded. If that is what is happening when "the
stepper motor goes funny and doesn't stop" you should try changing your driving
frequency or if you are using a six-wire two-phase stepper you may be able
to change the wiring configuration to allow more torque or a faster frequency
response.

-Jim

F.Ducret@sussex.ac.uk wrote:
>Hi!>I edited a code with labview to control the motion of my stepper motors>by
simply sending a command to the serial port 1, this command depends>on the
controller card.>It works absolutely fine but when the code is running for
long, the>stepper motor goes funny and doesn't stop , I have to switch off
the>controller card power supply resulting
in the lost of the reference>point
I have previously set up.>It might be the buffer memory getting full, I tried
to initialise the>port without any success, it still does it.>It is crucial
for me to solve this, the stepper motors are used to>transverse optics such
as lens and mirror. If this happens again the>optics could be crunched.>Thanks>>Fabrice>>>Sent
via Deja.com http://www.deja.com/>Before you buy.

[Chris]

On Wed, 12 Jul 2000 13:31:53 GMT, F.Ducret@sussex.ac.uk wrote:

>Hi!
>I edited a code with labview to control the motion of my stepper motors
>by simply sending a command to the serial port 1, this command depends
>on the controller card.
>It works absolutely fine but when the code is running for long, the
>stepper motor goes funny and doesn't stop , I have to switch off the
>controller card power supply resulting in the lost of the reference
>point I have previously set up.
>It might be the buffer memory getting full, I tried to initialise the
>port without any success, it still does it.
>It is crucial for me to solve this, the stepper motors are used to
>transverse optics such as lens and mirror. If this happens again the
>optics could be crunched.
>Thanks
>
>Fabrice

I
can't help with the main problem, when I was working with lasers and
stepper-driven optics everything was done with hardware.

But to protect the optics in the event of problems, I added safety
microswitches at the ends of the allowable travel which simply cut the
power to the motors.

Instead of relying on initially-set 'reference points' and trusting the
steppers to keep in step, we used multi-turn potentiometers attached to
the drive shafts, which gave us an absolute position at all times.

Just a couple of ideas,

Chris