Positional vs Continuous Rotation Servo Motors

0:00 introduction
0:25 positional servo
0:48 arduino servo library
1:42 continuous rotation servo
3:42 potentiometer control
4:48 pulse width modulation

#STEM #sciencebuddies #arduino #electronics
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[nowhereman]

I am a DIY beginner and I purchased mg90s for my mearm project. My servo motors do not indicate "360" on the label and it took me a half day to figure it out! Thank you for your video, it is a nice lesson for me.

[pinsetter]

huge props to you my good sir. spent 2 days trying to figure out why my servo wouldnt stop spinning hahah

[picknikbasket]

Very useful, thanks for this clear and concise video covering a tricky topic.

[rowantan]

thanks for the tip .Thought i got the right motor untill i wondered why it was spinning at 130 degrees and stopped at 90. Bought a sg90 thinking it was a positional and ended up with a continuous rotation servo motor

[rcworldKenya]

Thanks for this, I now have an idea of what servo to use for my RC car project.

[Dragonier]

Thank you this finally makes sense! I was trying to use .write to change thr position of a continuous!

[Bubu]

It's worth pointing out that you cannot short the pwm pin to ground or VCC and expect it to work, even though it technically qualifies for PWM at 0% and PWM at 100%, respectfully. The PWM range must be between 1% and 99% so that the controller in the servo can sync with the pwm frequency and calculate the on/off ratio.
However, if it's a 360 servo, it SHOULD work by shorting the PWM pin to ground or VCC to control the direction, but you will not be able to make the motor stop without a 50/50 duty cycle PWM signal.

[smcgrady]

Brilliantly effective demonstration - thanks

[obadaaltabaa]

Thanks for clearing things, i was using a positional 180 degree servo then i switched to a 360 degree rotation servo and it went crazy i thought it was broken😅

[sniS_ynnhoJ]

we bought two servos for an arm and we were wondering why does it keep spinning turns out its not the usual positional servo. thanks to this vid

[Zerkx]

Seems like I ordered the right ones on accident. Lucky!

[chaechaeyam]

Do I need a 180 degree servomotor modification to rotate 360 degrees indefinitely?

[anirbanroy]

Can we control the rate of rotation of the motor?

For example, I want to rotate at 45 degree per sec till it reaches 90 degree. Is it possible?

[maousama]

do you know how to make it with timing, for example when it rotate 90degree then stop rest for 10 minutes and continue 180degree can you help me

[rxjcbgc]

thanks for the simple explanation. one more curious point is that do both servo has the same torque or not?

[DannyMaes]

Hello,
I have a question about a positional servo, which could be used to move a pencil up or down on a sheet of paper.

In my view, the use of myServo.Write() is very straightforward, you need only 2 different values, to select one of the 2
servo positions (up or down).

In Arduino Nano code, I have seen this implemented by using a Timer2 (to generate a pulse width of 1ms/2ms and fixed
period of 20ms), addressing the registers OCR2A and OCR2B, loading it with value 156 or 148).

Why would one choose the second implementation for positioning the servo motor?

Thanks for this clear explanation about positional and rotational servos.

[justinmallaiz]

Thankyou!.. I'm interested in the opposite. (As a mini esc and motor setup, I want to reduce the sensitivity/range of motion). I prefer to keep the potentiometer to set the trim. I Should be able to connect 2 resisters in parallel (outter to inner). Has anyone tried, or can confirm?

[Lennings]

If the servo is not moving. is it still draining power?? in that case, it may not be good to use a servo in an application where it will be on for days. it may damage the servo?

[priyammascharak]

But how do i set the angle for the continuous rotation one is there a library for it or do i just have to fiddle with speed and timing?

[predator_x]

Hi, can i use 360 servo for a arduino robot arm (potentiometer arm)?