Correcting a 'wobbly' path between Waypoints?

For some reason I could not view anything on the log that was sent. I could not graph anything. problem on my end I guess. With my boat I have noticed that my I is 1/10 of my P and then I tweak the NAVL1 to smooth thing out. The way I have tuned was to play with P and I to the point that the boat goes in a very straight line but weaves back and forth really fast. Then try a little less I and NAVL1 a little higher till things smooth out. Every boat will be different. I still also look at the sea state that you run in. I usually run in fairly calm water and when I don’t my rudders work harder than I really want them to but the boat maintains course.

Regards,
David R. Boulanger

I think you are spot on in saying that each boat will be different David, but I would add that changing the speed of a craft also makes a big difference, just as it does with a autopilot on a big boat. If only it was as simple to adjust the Pixhawk as it is on a real autopilot.

As ArduBoat owners we should compile a database as follows:-

Here’s mine:
Length of Craft - 2.9m
Type of Craft - Trimaran
Power - Gas 2.5hp Suzuki Four Stroke
Top speed - 22kph
Flight Controller - Pixhawk 1
NAVL1_PERIOD =
STEER2SRV_P =
STEER2SRV_I =

Can you send a link to another log with the wobbly path when the NAVL1_PERIOD is set higher and I’ll have another look?

Thanks, Grant

Spent the whole day yesterday adjusting parameters and managed to get it pretty close to straight using the following settings:-
NAVL1_PERIOD = 20
STEER2SRV_P = 6
Cruise Speed = 4m/s

Strangely enough it behaves better in one direction and worse when coming back?

i think may be your steer servo’s problem, it’s response is too slow to process the steering timely

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