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Re: How to control a stepper motor using SD02B?

PostPosted: Sun Mar 27, 2011 12:53 am
by fremond
thanks a lot^^

Re: How to control a stepper motor using SD02B?

PostPosted: Thu Apr 07, 2011 8:33 am
by fremond
excuse me..can i ask whether cytron provide a microcontroller which can connect two SD02B and to UC00A??..

Re: How to control a stepper motor using SD02B?

PostPosted: Thu Apr 07, 2011 2:37 pm
by sich
You can try PR27 Multi-UART interface. It's using software generated UART to communicate with more than one UART interface.

Re: How to control a stepper motor using SD02B?

PostPosted: Sat Sep 24, 2011 3:46 pm
by sam
Hi,
Would like to know the kind of drive use in the SD02B. Is it a simple voltage drive (without current limiting), the L/R drive (i.e. that employs series resistors), or the chopper drive (that allows Vsupply >> Vrated and current limiting via feedback-driven switching of the H-bridges)?

I suspect it is the simple voltage drive since there are no means to set the current limit per phase on the SD02B board.
Waiting for your kind reply :)

Regards,
Sam

Re: How to control a stepper motor using SD02B?

PostPosted: Sat Sep 24, 2011 6:05 pm
by sam
Hi,

I have another question.
From the user guide, it states that the maximum frequency of pulses is 1000 pulse per second(1kHz).
It is a known fact that microstepping can make the motor rotates smoother(i.e. less vibration).
Question:
If i were to use a pulse rate of 1kHz, full step mode, i will be expecting the motor will give more noticeable vibration compare to a setting of pulse rate of 1kHZ, 1/10 microstepping mode.
But that implies that i will sacrifice speed in favour of a smoother rotation, right?
Also, am i allowed to increase the pulse rate to 10kHZ with the 1/10 microstepping mode so that i can maintain the same speed plus a smoother movement?
Once again, will be waiting for your kind reply:)

Regards,
Sam

Re: How to control a stepper motor using SD02B?

PostPosted: Sat Sep 24, 2011 6:47 pm
by sam
Hi,

I yet have another question even though all my post has not been answered:).
Pertaining to the pulse input pin of the SD02B is it edge triggered?
Because if it is not, it seems that the duty cycle (i.e. pulse width) of the pulse input will affect the operation of the motor.
For example, if it is not edge-triggered, a longer pulse width will cause the coil to be energised longer, in other words it might affect the ramping og the stepper motor.
Please help to clarify as the user manual seems to be lacking a lot of essential information.
Thanks in advance.

Regards,
Sam

Re: How to control a stepper motor using SD02B?

PostPosted: Sun Sep 25, 2011 3:50 pm
by kl84
sam WROTE:Question:
If i were to use a pulse rate of 1kHz, full step mode, i will be expecting the motor will give more noticeable vibration compare to a setting of pulse rate of 1kHZ, 1/10 microstepping mode.
But that implies that i will sacrifice speed in favour of a smoother rotation, right?
Also, am i allowed to increase the pulse rate to 10kHZ with the 1/10 microstepping mode so that i can maintain the same speed plus a smoother movement?
Once again, will be waiting for your kind reply:)


Hi sam, I can't answer your question but I think this post has some info you need. And yes, I believe you need to sacrifice either speed or smoothness, as that 20kHz should be the max frequency that is limited by the mcu on board.

Re: How to control a stepper motor using SD02B?

PostPosted: Sun Sep 25, 2011 4:30 pm
by sam
Hi kl84,

Thanks for the reply, anyway do you have any idea regarding two of my earlier posts?

Regards,
Sam

Re: How to control a stepper motor using SD02B?

PostPosted: Mon Sep 26, 2011 1:36 pm
by kl84
AFAIK, it's using simple voltage drive. But I used this driver some time ago, not sure if they changed the firmware.

Re: How to control a stepper motor using SD02B?

PostPosted: Mon Sep 26, 2011 4:02 pm
by sich
Hi all,

Sorry for the lack of info in our user's manual! We're improving bit-by-bit. Thanks for your feedback ;)

The current SD02B stepper driver firmware implements the chopper drive method. PWM applied to the H-bridges changes according to the current feedback. However, the current limit settings is not accessible to the user.

About the speed vs. smoothness, kl84 has pointed you to my previous explanation.

Pulse input pin for SD02B is edge triggered. It captures every rising edge of the input pin.