Source
r/rccars•
LegitimateWorkUser

I have a radio and an extra SBUS/PPM receiver for my quad copter. I also have some ESCs. How can I use them to drive a 2-wheeled vehicle?

I'm putting together a combat robot. Is there some kind of controller board I can get that will accept an SBUS/PPM receiver and deliver a signal to the ESCs? I have two drive motors (left and right) that I'll use to drive and steer the thing. And then I have the weapon drive motor. Ideally I'd be able to control the rates on the motors like I can with my quad in betaflight, but I don't know what exists for RC cars/trucks that would allow me to do this.

Posted Dec 20, 2017, 3:58 PM UTC

36
absolutgonzo•

RC cars don't use flight/controller boards. Servos and ESCs plug directly into the receiver (PWM).

3
shitterplug•

You'll need a PWM receiver so you can plug the ESCs or tank controller directly into it. SBUS/PPM require a flight controller. You'll need a tank controller/mixer board for the motors. They're pretty cheap. Radios don't have tank mixing. On too of that, you'll need reversible ESCs that'll work with the tank mixer. You'll have to get on some robotics forums to figure out what ESCs you can run. Surface ESCs are forward-brake-reverse, you need a forward-reverse ESC. The air ESCs you currently have are forward only.

How fast does it need to go? You might want to look into driving it with continuous rotation servos and using v-tail mixing to control left or right.

2
LegitimateWorkUserOP•

That's cool. The ESCs I have for the bot are more like this. Hopefully those should work. And I think I found a pwm receiver that should work.

The tank controller/mixer board is new to me though. I'll have to research it. Thanks for pointing me in the right direction!

This bot uses titan 775s with 38:1 gear boxes and 4" wheels. If the motors could run at full speed, I'd max out at about 8-10 mph. I already have the motors and gear boxes, but I'll definitely look into V tail mixing because I plan on using my aircraft transmitter.

2
shitterplug•

Oh, for some reason I thought you were also planning on using the drone motors. The ESC you use will need to go from forward directly to reverse. The one in the Amazon link is forward, brake, reverse.

1
LegitimateWorkUserOP•

Oh I see. I'll look into that. Thanks!

1
absolutgonzo•

Radios don't have tank mixing.

Depends on the radio. Some transmitters can basically mix everything.

Surface ESCs are forward-brake-reverse, you need a forward-reverse ESC.

There are tons of surface ESCs that support forward-reverse as a setting, especially all the crawler/scaler ones.

1