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Topic: Manual control of flight controller thrust (Read 245 times) previous topic - next topic

Theturrets

I am building an octocopter for a school project. I want to control the height of the octocopter with a mechanical tow bar, moving the tow bar up to increase thrust and lowering the bar to reduce thrust. The motors will be controlled by an afroflight32  and I would like to replace the digital signal normally given by a radio receiver to a signal generated from a potentiometer connected to the tow bar angle. I have been told by a local hobby club that Arduiano has a board which can convert a potentiometer signal to a flight control motor signal. Has anyone any information that can help me convert an angular tow bar movement into a flight controller thrust signal.

AWOL

A tow bar?

You mean the thing on the back of a car or truck you hitch a trailer to?
"Pete, it's a fool (who) looks for logic in the chambers of the human heart." Ulysses Everett McGill.
Do not send technical questions via personal messaging - they will be ignored.
I speak for myself, not Arduino.

Theturrets

Yes I do mean a tow bar as you would use to tow a trailer but this trailer will fly using 8 motors.

vinceherman

#3
Jul 02, 2018, 02:11 pm Last Edit: Jul 02, 2018, 02:14 pm by vinceherman
You are going to have to give more details.

Your description of using a towbar to fly a trailer does not give me enough understanding of your intent to offer much advice.

This is a tow bar.  Is this what you are talking about?  How will you change the angle of this tow bar so that you can measure it with an arduino?



Next up, do you have a flying octocopter?  You mention you want to control the height.  Do you know that there is a *lot* more to controlling a drone like this than a single height command?

Theturrets

My description of tow bar may be misleading. I want to pull (tow) a flying platform with 8 lift motors using a small bar hinged on the vertical plane. The platform is 50 x 50 cms and I would like to attach a bar to the front of the platform, approximately 50 cms long to a control which would control motor throttles. With the bar depressed i would like the throttle to reduce and bar raised i would like the throttle to increase so that when walking and holding the bar platform would follow the user and respond to height changes as the bar is moved up and down. Generally height control would be augmented using a height module.
I am building the platform with the help of BAe and appreciate that roll, yaw and pitch need to be controlled and stabilized using a flight controller. I was told by the local model club that an Arduino control would accept a voltage input from a potentiometer and convert it to a digital motor input. This potentiometer would be connected to the bar. He had no further details on the Arduino control. Do you have any information that can help.

slipstick

It still doesn't make much sense but...What range of movement will you have? How do you plan to connect the "bar" to a potentiometer? They're not designed to take side loads and most expect to work over approx. 270 degrees.

If you can arrange the mechanical side it's easy enough to read some sort of voltage with an Arduino but how you would convert that into whatever input signal your "height module" requires is anyone's guess. Since you will have multiple motors being coordinated by a flight controller it is presumably not exactly as simple as a "digital motor input" or perhaps it really can be as simple as what we would normally think of as a throttle signal with all the interesting work done in flight controller. I'm just guessing here because you've provided no real information.

Steve

Theturrets

All I want to do is change the thrust of the motors using a lever system. think of it as a  manual throttle. i know I can do it with radio control but I want to this manually. The throttle lever would be fixed to the front of the platform and only move in the vertical plane in relationship to the platform. The angular movement of the potentiometer can be governed by gearing. If a voltage from the potentiometer can be converted to a digital thrust signal to the flight controller i would like to know if Arduino have a board that can do this. The rest of the construction is feasible. I already have the solution to keep the platform level

slipstick

You haven't said what "digital thrust signal" your flight controller needs. But if it's anything normal like for example the throttle signal you get from an RC receiver then any Arduino board can read one potentiometer and convert the result to a throttle signal like that. It's so easy that the Arduino IDE has a basic example program called Knob that does exactly that.

I'd probably use a Nano because it's fairly small and I'm used to them but there are loads of other boards that would work if that's all you need it to do.

Steve

slipstick

You haven't said what "digital thrust signal" your flight controller needs. But if it's anything normal like for example the throttle signal you get from an RC receiver then any Arduino board can read one potentiometer and convert the result to a throttle signal like that. It's so easy that the Arduino IDE has a basic example program called Knob that does exactly that.

I'd probably use a Nano because it's fairly small and I'm used to them but there are loads of other boards that would work if that's all you need it to do.

Steve

Theturrets

Thank you Steve. That's exactly the advice i need. The board will be ordered very soon.

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