GPS-less navigation possible?

Hello there,
I am living on a mountainside with an area about 600-800m^2. I have 3 trees there on the side. I’ve teached my yarbo to mow this area and marked every tree as a no-go-area. The result is more or less okay, but after all there are 3-4 lines of gras, which my yarbo missed mowing. Meaning a line about 5-6m long and 10-20cm wide. This missed lines are not under the trees, so I wonder what caused my yarbo to miss this lines. There seems to be no logic yet, to do a GPS-less navigation, meaning: gyroscope or inertial navigation, like the common indoor vacuum cleaners.

On my map, I’ve set a non overlapping mowing tactic, but in my opinion, a width of 10-20cm width missing line shouldn’t be there.

I’ve change also the mowing from linear / chessboard to spiral. ATM, spiral seems to be the best for me.

So after 2h of automatic mowing, I fix the missing lines by manually mowing by manually controlling yarbo.

Are you mowing on a slope? I’ve seen people mention that strips of grass may be left behind while Yarbo is going along a slope. I suspect it’s due more toward needing gradual corrections in the mowing line than a GPS failure, but I don’t know.

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You need to do overlap to account for any deviations or track slippages and sliding that may happen on the slope. You may have to go with more overlap if it persists. There’s also a weird pathing issues with obstacle avoidance currently where it doesn’t track the line but parallel to it for a really long distance. I’m hopeful they can get this fixed soon.

ATM there is a problem with yarbo missing lines. See my post and Yarbo answer? They are working on it, the latest firmware update, unfortunately, brought no solution, but it did a little better.

Yarbo missing lines.

@bryan.wheeler As I understand it, the problem lies in the slope. The algorithm calculates it wrong l, when the area is tilted.
I can not set more than 20cm overlap in the app, so at the moment there is no good solution. I tried Checkerboard and parallel, no difference in the outcome.

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Maybe but from what I’ve seen it calculates the line and the rover does not follow it sometimes after performing maneuvers. That is when grass is being missed from what I’ve observed. It tracks parallel to the line for a really long time and slowly moves inward toward the line.

The problem is, that on a “flat” area you can “calculate” the path in 2 dimensions, with a slope, in my case a steep one, you have to calculate the next waypoint in 3 dimensions.

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You are correct that there is more that needs to be accounted for in 3D than 2D (e.g. planned lines on the map that are perpendicular to a steep slope need to be closer together than lines on a flat ground).

However, I’m not even seeing this as the main issue with Yarbo missing lines on hills. From what I (and I think @bryan.wheeler) are seeing is that every time Yarbo misses grass on a hill, you can watch/see Yarbo NOT following the planned line in the app (on the map). Also note that it even misses lines on small hills or when going straight down hills.

This means it has more to do with their algorithms being too lenient when Yarbo gets off course (Yarbo should correct its position to align with the planned path before proceeding to mow ahead) OR their IMU and other sensors are reporting bad data and that is overriding the more correct GPS positioning.

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Thanks for the response.
Yes I am mowing on a slope, also overlapping by 4 or 8 inches didn’t solve the problem.

Here’s how it looks currently:

And on the live map, there seems to be no issue:

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