Poor Accuracy with my own base station

GPS / RTK / GNSS
1

Hello All,

I have set up a base station and am casting through RTK2GO. I am connect to my base station under the source table and the little satellite is green. When driving in the field my tractor seems drunk lol and I have played with the pwm settings (using a keys motor) and have it driving a little better but I think it must be the RTK accuracy? It bounces between 20-30 cm while driving. I would really appreciate any suggestions.

Could internet speed play a role?

Thanks!

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2

No that looks like a was or a steer settings problem. If you look up in the top left corner where it says rtk age or something like that you want a small number like one or two. Your picture isn’t super clear but it looks good. That means you’re connected to you caster in a timely manner so no Internet problems. You will get a message on screen if it’s bad.

I believe what you are referring to as accuracy is actually the distance between gps fixes.

3

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Thanks for the response, RTK age is 1.6. I am using the WAS that was already in the tractor and a 4th gen KEYA motor. Where it says 26.9 cm is that not the accuracy of the gps signal?

4

No. It’s the distance between 2 GNSS positions. Should be near 0 at standstill and go up the faster you drive.

5

Some CNH tractors have bad WAS apparently.

If you drive manually straight, then little right, then come back straight, then the same left, does the steer angle always show 0(or 0-0.3 range) when driving straight?

6

I see that the CPD must have reset to 100, I thought I had set it the day before and I have lowered it back to 47 and Ackerman of 91 as per the wizard. I am hoping that’ll straighten it out as the wheel turned full lock left or right didn’t get the degrees above 8-10.

Fingers crossed thanks for the idea to check the was.

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7

That number that bounces between 20-30cm while driving is the distance between fixes, which come in 10x a second. You’re moving 200-300 cm per second, 5-6.5 mph. What’s the number when you stand still? It should be 0.0 cm, there may be some occasional ~1.0 cm jitter.

I think your issue is tuning related, but I also think your base station signal isn’t very good.

Here’s my base with ANN-MB (square black patch antenna)

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Here’s buddy’s base with the ardusimple survey antenna

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You shouldn’t have so many satellites below 35 db.

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