Stanlee vs Pure Pursuit

What’s everyone using out there…I have been running with Stanlee Steering and haven’t tried PPursuit. What differences do you notice between the two?

I use PP under 15km/h
I use stanlee more than 15km/h

I can’t reach 5cm accuracy avec pp more than 15km/H , but with stanlee less than 5-7cm at 30km/h !

Just for comparison:
At work i use SBG Geostar 200, and at 5 to10 km/h it normally oscilates ± 5 cm (it can go 20 to 50 m on 0 cm but then ± some cm off line then 0 again)
It can follow a line at 15 to 18 km/h if you manually start it at the line ± 10 cm, but if it is more off it oscillates wildly.

@Tooki57 May you can give us a hint what values you have adjusted in PureP?
Most of my work I do between 5-10km/h but i`m struggeling with the values.
Some times it is oscilating like crazy and some times it does not realy steer and drives away a lot from the line.
I have the antenna slighly in front of the front axle, i am not sure if that is generally a bad position for PureP .

Thanks a lot.

Hello, I advise you to review the videos concerning the settings. My settings on my tractor, with my electric motor and its assembly, are
30 Prop gain
min pwm 16
ahead pp 1.8 (1.6-2.5 depending on speed)
min ahead 2.6m

But once again these settings are specific to each installation.

How stable is your heading? Both methods rely on a quite stable heading. Without auto steer on at your desired speed, make sure your heading is quite stable.

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@Tooki57 Thanks for your feedback. Yes I know that the values have to be adjusted for every tractor in detail. I only wanted to know some range other people have adjusted, if they have it closer to 5m or to 0,5m.

@BrianTee_Admin I guess my heading is quite stable. I have let the tractor stand still for half an hour and the BNO heading driftet only around 1°. While driving along a straight road it was moving around ±0,5° depending on how straight I was able to steer.
What I recognized is that in PP the tracor is going very smooth and less oscilating but often it is going around 15cm parallel to the A-B line. It does not want to steer back on the line, so I thought maybe I have to turn down the look forward values.
The fix to fix heading distance is set to 1m.

How accurate is your wheel angle sensor (WAS) center? Usually when it drives parallel to the AB line, it’s because your WAS isn’t centered.

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Thanks for that hint. When I have the feeling that I am manually steering a good straight line the wheel angle is somewhere between ±0,2°. I do not know any better solution to find the 0° point than driving along a straight street.

That should be close enough for zeroing. Seems odd you are getting 2 very different problems - usually it is just one or the other.

Thanks @BrianTee_Admin, will check my WAS maybe i got a bit noisy signal.

Is there some recomendation for Fix to Fix distance of heading. Standard value 2m is fine?
The heading correction by BNO in slider middle position is also fine?

If you have a stable heading 1m works well, but if you are mostly doing abline 2 or 3 and no imu, 2 or 3m meters calms the steering down.