Page 1 of 1

Throtlle body with PWM RC servo

Posted: Wed Sep 10, 2025 6:21 am
by r8d8
Greetings,

I would like to use serial servo for throttle body.
Something from Waveshare with serial bus communication and magnetic encoder.
https://www.waveshare.com/product/robotics/motors-servos/servos/st3215-servo.htm
Would appretiate any info, maybe someone already have tried this. Haven't found anything on forum so far.
Using one servo I can combine actuator and throttle encoder.
Targeting microRus.
It will require schematics and software change, I can manage it. Just don't want to reinvent wheel, if some progress already exist

Best regards,
Constantine

Re: Throtlle body with PWM RC servo

Posted: Wed Sep 10, 2025 10:09 pm
by langwadt
if you don't want to reinvent the wheel, then why don't you use a standard electronic throttle body?

Re: Throtlle body with PWM RC servo

Posted: Thu Sep 11, 2025 6:51 am
by r8d8
Hi,
Because i need to machine small throttle body,
My target is paramotor engine, 2 stroke, Polini Thor 202, single cylinder
https://www.polinithor.com/en/polini-thor-202-2/

There is not much components from cars, that I can reuse

Re: Throtlle body with PWM RC servo

Posted: Tue Sep 23, 2025 7:41 pm
by mikedjames
Why not take an idle air control valve and scale it up for the airflow- use a stepper motor and lead screw driving a cone into a hole ?
It does not need to be using a butterfly flap to control the throttle, any kind of variable valve will work, provided it can maintain the air flow needed.

If it is being used with an aero engine things will change more slowly.

Or you could take the stepper drive signals intended for an electronic throttle valve and intepret the drive pulse sequence as a position count and control a PWM for an analog servo using a single microcontroller.

Re: Throtlle body with PWM RC servo

Posted: Sat Sep 27, 2025 5:28 pm
by mpgmike
It's been a few years, so I don't remember who the supplier was, but I did a 1500 watt genset project that included fuel injection. I designed & built my own controller for it, but the throttle body and injector was sourced. You may be able to find what you need commercially available, especially since newer riding mowers are fuel injected.
Gen_10_23_19.jpg