Set 1250rpm any method

Other Hardware Motors, Mechanics, Power and CNC
1

I need 1250rpm.
I don't need torque. I'll just turn light things.

I have an rpm meter.
I have an adjustable power supply.

To summarize the question
I need 1250rpm. The method doesn't matter.
I don't know what to buy.
I don't know HW. It has to be usable with Arduino libraries.

If I want to turn a stepper motor to 1250rpm, should I use X nucleo IHM03A1 powerSTEP01?
Is it easy to set 1250rpm exactly?
I try nema17 stepper motor + a4988 but only about 1000rpm

How about bldc + esc?
I'm going to use drone motors and esc because they're easy to access. What do you think?
esc:Regulator ESC DJI 30A OPTO
Current: 30A OPTO
Signal Frequency: 30Hz ~ 450Hz
Battery: 3S ~ 4S LiPo
bldc :A2212/15 930KV

I found a sample made with servo.h.
But it's so fast that I'm worried that the minimum speed will exceed 1250rpm. Because it can only be adjusted from 0 to 180.

  1. DC motor + voltage adjustment
    The mini car motor is about 1000 to 2000 rpm.

Try adjusting the voltage while manually measuring the RPM.

This is what I thought 3 way.

If there is a good method, please let me know.

I am a SW engineer, try to do HW.

I am not a native speaker. My English will be weird. Please help me.

2

How exactly do you need?
Is 1250 RPM +/- 50 RPM OK?

1 Like
3

This might work for you

1 Like
4

yes

5

See the link to the motor I show in post #3 . It has an encoder so you can probably control the speed to within +/- 5 RPM and it' fairly cheap.

6

That would be a 1250*200/60=4166.7Hz step rate, or 1000000/(1250*200/60)=240us/step. That should be easily achievable. What did you use to get to 1000RPM?

You might want a stepper library capable of acceleration and pulse rated greater than 4167Hz. Mobatools or AccelStepper on a faster-than-16MHz processor should work fine.

Performance
The fastest motor speed that can be reliably supported is about 4000 steps per second at a clock frequency of 16 MHz on Arduino such as Uno etc. Faster processors can support faster stepping speeds. However, any speed less than that down to very slow speeds (much less than one per second) are also supported, provided the run() function is called frequently enough to step the motor whenever required for the speed set. Calling setAcceleration() is expensive, since it requires a square root to be calculated.

Gregor Christandl reports that with an Arduino Due and a simple test program, he measured 43163 steps per second using runSpeed(), and 16214 steps per second using run();
-- AccelStepper: AccelStepper Class Reference

image
image1544×586 42.7 KB
-- MobaTools/MobaTools-260-en.pdf at master · MicroBahner/MobaTools · GitHub

7

Without libraries.
I created the pwm signal myself.

digitalwrite(3,high)
delay(1)
digitalwrite(3,low)
delay(1)

I confirmed with an oscilloscope that the pwm signal was created.
However, when it exceeds 1000rpm. The motor makes a beeping sound and does not turn.
It's okay when you turn it very slowly. However, at around 900 rpm, you had to turn it by hand to start it.
However, when I input the PWM at over 1000 RPM, it doesn't start even if I start it by hand.
It is a 200 step motor.
I tried both microstep and full step driver settings.

8

It could be that your code doesn't do acceleration and is moving the electrical field faster than the physical motor can catch up with. Do you have pull-in & pull-out torque curves/specs for your motor?

9

42BYGH34

motor model no.

I don have " pull-in & pull-out torque curves/specs"

10

Then you need them. Aim to ramp up to the final speed in about one to two seconds.

11

Have you set the current to your motor requirements?
Can your power supply provide enough current?
Which Arduino are you using?

12

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