RC Pitch stick seems in a wrong direction

ArduCopter
1

Hello,

I am quite new here, so the answer may be “the behavior you notice is usual”…

I had a weird feeling during my first flight with my drone: the Roll stick is ok, but the Pitch stick seems in the wrong direction.
When I want to “move to the right”, I move the stick to the right, RCIN increases, the Roll gets positive, and my drone moves to the right.
When I want to “move forward”, I move the stick up, RCIN increases, the Pitch gets positive, and the drone moves backwards.

I am using the V 4.6.3 of Arudcopter with a DakeFPV H743 FC. From Mission Planner, I see that the gyroscope is in the “right direction”: when I lean the drone to the left / front, I see the right movement on the MP screen.

The motors are well connected, in the right order, and they rotate in the regular direction (inwards in the front and the back, so outwards on the left / right).

It this a normal behavior? Shall I change the configuration of my RC?

Thank you for any clue!

2

You need to invert the pitch channel on your RC transmitter

3

Isn’t the recommended option to set RC2_REVERSED instead of inverting it on radio? Perhaps I have heard that from Chris Rosser videos, but at least You would not have to remember to do it on radio when You switch to another model.

4

When reversing RC channels, it’s rather immaterial whether you do it on the radio or via parameters. That comes down to user preference.

Ignore Rosser. His advice has proven poor countless times.

2 Likes
5

I wonder if there is somewhere list of things considered as bad advice from Chris’es tutorial as sort of summary what not to do :slight_smile: .

6

There is an extensive list of what TO DO in ArduPilot’s own documentation.

Listing Rosser’s mistakes is a waste of time. I will say that one of his biggest errors is in filter configuration, and it has caused a lot of confusion here.

I also wish this weren’t the case. His presentation style and popularity would be outstanding if he were willing to engage with the team here and improve his video series. He has ignored all attempts to contact him regarding such.

1 Like
7

Well, thanks! I’ll opt for the Parameter.
I just wondered if I had done something wrong, and if it may induce a weird behavior later on.
(But clearly, I wonder why the parameter is not pre-set by default… I suspect the problem is the same for every newbee…)

8

It’s a longstanding holdover from early days of DIY builds, and reversing it by default would be a breaking change for a lot of pre-existing builds. It will live on as an annoyance, at least for now.

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9

The inverted pitch makes sense if you correlate the decreasing pitch PWM values with decreasing pitch angle ie, pitch down, and vice-versa.

10

It never made sense. It was one guy’s opinion long ago, and it stuck.

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11

Then we are onto why the convention of pitch downwards = decreasing PWM and not the other way around. As petty as assigning the convention of roll left = decreasing PWM and vice-versa :man_shrugging:

12

But I did not see any mention of this topic in the doc… Did I miss it?
It must be a pain point for everyone… And you all concede it…
If it were up to me, I would put a big red bold framed flashing paragraph in the doc…

13

Pretty sure it’s there on RC Calibration page. Well, admittedly, for copters it doesn’t make much sense where you are controlling the horizontal motion but it makes sense when you think in terms of a plane where you pull back the stick to pitch up

1 Like
14

You are right, the doc says the following. I did not pay enough attention… :
For pitch, the green bar should move in the opposite direction to the transmitter’s physical stick. This is not the default for many transmitters.

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15

Yes, I think what happened was, as Yuri told, from the RC plane days where a forward push of the stick has to make the plane pitch down and internally, the convention set was to equate lower PWM values to a pitch down maneuver. But physically, when you push up the stick, you get increasing PWM, the opposite of what was required by the convention.

16

You’re reading too much into this. It was simply an opinionated decision. Basic RC plane convention would be stick back decreases PWM and increases pitch. Somebody wanted otherwise for Arduino based quadcopters for reasons I will never understand.

17

Okay I thought it was always the way as in Ardupilot.

Maybe the person’s opinion was that it was more elegant in code to make pitch angle directly proportional to PWM rather than inversely proportional? I’m not sure but just guessing. With basic RC, you would not be involving an autopilot right so no need for this “elegance”?

Sometimes I get curious and caught up with nuance :slightly_smiling_face:

18

If I had to venture a guess, this convention for AP has more to do with game controller familiarity than aviation or RC convention.

1 Like