Two RC receiver inputs on the Pixhawk 4?

Using a Proboat blackjack as a base and hull, with the Pixhawk 4, how do I connect two RC receiver pins to the Pixhawk 4?

Looking at the Pixhawk 4 pin out there is only three pins for the radio control receiver input, those being signal, power, and ground.

but the boat has separate pins for Thr and Str which I took as thruster and steering.

I feel like this is a quick fix and I just missed something within the Pixhawk setup. I searched before posting but no luck.

Assuming those are control signal inputs you are talking about they would be connected to Servo outputs on the Flight controller. You have assigned throttle and steering outputs right?

Most modern flight controllers cannot read each channel of the RC input separately. If you can, configure your receiver to send one of the protocols listed here: Radio Control Systems — Rover documentation

If that is not an option, you can get an external board that will combine the signals for you, such as this one (I just got the link from a keyword search, have not bought these in a while)

I think those boats come with a receiver that is meant to connect to individual servos and ESCs (speed controllers) like an ordinary radio controlled model.
You either need one of those adapters to combine all the PWM signals into one PPM signal for the flight controller - or get a new receiver that has a single output for PPM or SBUS, something modern.

The servos and speed controllers plug into the flight controllers servo or “main out” connections.

So following the Ardupilot documentation, I have the rudder and the prop connected to the output pins 1 and 2 on the PixHawk.

I don’t need control of the boat by any means really so can I forgo the receiver and a controller altogether?

Ah okay makes sense.

Thanks for this option.

I asked it above but can I forgo a controller altogether?

Yes correct, it is by no means a hobbyist boat, its very much an ordinary radio-controlled boat.

Do you have a suggestion for a new receiver and controller?

I do have the rudder and prop connected to pins 1 and 2 of the main out on the PixHawk.

Sure. Connect the Receiver outputs to the Motor ESC and Steering Servo inputs and drive it manually. Most RC vehicles are setup this way. People add Flight Controllers to Rovers and Boats to do some assisted or automated things.

In fact driving in manual Mode is essentially bypassing the Flight Controller although there are some useful functions.

To clarify,

take the wires from the motor and steering servo, and put them into the Pixhawk?

I think I’m confusing myself with the inputs and outputs too.

What I wanted to do was to have a way to control the boat by the stock, cheap, remote if need be, but its not a must.

It’s not ideal but I’m able to forgo any sort of controller.

If you don’t have a need for a controller then don’t use one. It’s as simple as connecting the Rx outputs to the Motor ESC and Steering servo inputs. What RC system do you have?

Okay, thank you, just verifying.

I’m following the guides on Ardupilot, and they recommended a controller so I thought I HAD to have one.

Not much point in that if you are just going to drive the boat manually with a 2 channel RC system. Isn’t that pretty much off-the-shelf from Horizon with that boat?

I think Dakota is talking about an RC “Controller” (transmitter and receiver) and Dave is talking about a Flight “Controller” (autopilot).

If you want to use the autopilot for assistance and automatic features, you still need the RC transmitter and receiver in order to do tuning and set everything up properly, and to take over in case something goes wrong.

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Well, actually the idea is to program the boat to go a set GPS coordinate.

I already have a way to get the GPS location, next is getting the boat to guide itself there.

Yes, it’s off-the-shelf basic. but it suits my needs.

So I absolutely need a remote controller physical-object-you-hold-in-your-hand?

If it’s required, got it. I see what I can find that can get here quickly and hopefully have it installed in a week.

If it’s nice to have, it is not critical and I’d like to bypass that.

I have 2 or 3 weeks left, and it’s not going in open water to the point I can’t get to it by hand.

It just needs to be able to steer and guide itself to one point on a map.

Then you need a Flight Controller. You need an RC System also to get the boat configured and tuned properly. After that you could control it from a ground station but you need it initially. And the RC system it came with (if it came with one) is likely too limited to suit.