Tracid
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sla7042 project
Since i could not find any docs on how to microstep an unipolar stepper motor i figured out the sequences myself.
Hopefully i managed to rotate them.It seems i really broke one step into microsteps but when stepping it periodically it doesnt rotate at constant speed.Sometimes it stops for a little while then rotates continuously for a while then again stops.
I use high torque microstepping,so one half of the first coil is fully on,while one half of the second coil is going up and down(duty cycle from 0-100 and 0-100)
Today a reason came up on my mind,why isnt the motor rotating continuously(what came on my mind is my opinion only).
At the moment i am driving the coils the following way(unipolar drive)
ne half of windingA is at full power and one half of windingB goes down to 0% duty cycle.
After it reached zero,the current in another half of WindingB is increased.You can notice at step4 that only one half is at full power(no current is switched into any other winding).
case1:
step 1 2 3 4 5 6 7
duty100% ON ON ON ON ON ON ON
duty100-0% 3 2 1 0 0 0 0
dutt0-100% 0 0 0 0 1 2 3
And this is the second case i came up with:you can see that at step4 another half winding becomes increasing immediately after the first gone to zero.
case2:
1 2 3 4 5 6 7
ON ON ON ON ON ON ON
3 2 1 0 0 0 0
0 0 0 1 2 3 4
Can anybody tell me which of them is good?
Maybe that ´dead´ band (step4) causes the stop for a while.
PS: sorry about the arrangement,the editor shows it aligned,but when submitted it becomes unaligned!(even making more spaces in editor wont change the alignment.)
Since i could not find any docs on how to microstep an unipolar stepper motor i figured out the sequences myself.
Hopefully i managed to rotate them.It seems i really broke one step into microsteps but when stepping it periodically it doesnt rotate at constant speed.Sometimes it stops for a little while then rotates continuously for a while then again stops.
I use high torque microstepping,so one half of the first coil is fully on,while one half of the second coil is going up and down(duty cycle from 0-100 and 0-100)
Today a reason came up on my mind,why isnt the motor rotating continuously(what came on my mind is my opinion only).
At the moment i am driving the coils the following way(unipolar drive)
ne half of windingA is at full power and one half of windingB goes down to 0% duty cycle. After it reached zero,the current in another half of WindingB is increased.You can notice at step4 that only one half is at full power(no current is switched into any other winding).
case1:
step 1 2 3 4 5 6 7
duty100% ON ON ON ON ON ON ON
duty100-0% 3 2 1 0 0 0 0
dutt0-100% 0 0 0 0 1 2 3
And this is the second case i came up with:you can see that at step4 another half winding becomes increasing immediately after the first gone to zero.
case2:
1 2 3 4 5 6 7
ON ON ON ON ON ON ON
3 2 1 0 0 0 0
0 0 0 1 2 3 4
Can anybody tell me which of them is good?
Maybe that ´dead´ band (step4) causes the stop for a while.
PS: sorry about the arrangement,the editor shows it aligned,but when submitted it becomes unaligned!(even making more spaces in editor wont change the alignment.)
