Marking boundaries

[Banana Bar]

For various reasons we have numerous guidance systems on farm, Greenstar, Trimble, Claas, and Topcon ( all on Sim RTK).
We have decided that it is time we plotted all of our field edges accurately and plan to do this with the gator over the winter. My question is what system should I use in the gator to do this that can then be exported into all of the above systems. I have Gatekeeper so am happy to use that if it’s possible?

BB

 

[Clive]

use your boundary data from drilling ? (Assume its RTK ?) Just pull it into gatekeeper

 

[B'o'B]

I think JD are the odd ones out and have a system that makes north-south lines all parallel from pole to pole. Trimble and the others north-south lines follow the curvature of the globe and converge as they get closer to the poles. I believe on long runs it can make a noticeable difference. Can’t help you on how long a run it takes to be noticeable though.

 

[Clive]

I think JD are the odd ones out and have a system that makes north-south lines all parallel from pole to pole. Trimble and the others north-south lines follow the curvature of the globe and converge as they get closer to the poles. I believe on long runs it can make a noticeable difference. Can’t help you on how long a run it takes to be noticeable though.

surely lat/long is fixed

ive always assumed all hardware corrects for true north and magnetic variation etc ?

Our RTK boundaries don’t move (piloted 10 years ago now).

from an operations point of view all passes follow the drills data on headlands

 

[Banana Bar]

I could pull the boundaries in from the drill but I'm not happy they are accurate enough. I want true measurements of 1.25m from the top of ditch banks and 2m from hedge centres. I cannot hand on heart say we have this at the moment if anything we leave cross compliance strips too wide.

 

[Clive]

I could pull the boundaries in from the drill but I'm not happy they are accurate enough. I want true measurements of 1.25m from the top of ditch banks and 2m from hedge centres. I cannot hand on heart say we have this at the moment if anything we leave cross compliance strips too wide.

to get any more accurate I think you would have to do it on foot or quad with regular tape measure checks ?

 

[B'o'B]

surely lat/long is fixed

ive always assumed all hardware corrects for true north and magnetic variation etc ?

Our RTK boundaries don’t move (piloted 10 years ago now).

from an operations point of view all passes follow the drills data on headlands

You would have thought wouldn’t you.
It’s not to do with the lines moving, it is how the lines are calculated that differs between the systems.
JD do it differently to other makes.
If you run an a-b line north-south from the equator heading up to the North Pole the JD ones would run exactly parallel all the way up. All other makes would get closer together as you get nearer to the pole. The same as the lines on longitude on a globe do. I remember going to a talk by a US farmer on CTF and it was messing up his CTF system as he had both makes on various bits of equipment.

 

[Clive]

You would have thought wouldn’t you.
It’s not to do with the lines moving, it is how the lines are calculated that differs between the systems.
JD do it differently to other makes.
If you run an a-b line north-south from the equator heading up to the North Pole the JD ones would run exactly parallel all the way up. All other makes would get closer together as you get nearer to the pole. The same as the lines on longitude on a globe do. I remember going to a talk by a US farmer on CTF and it was messing up his CTF system as he had both makes on various bits of equipment.

how odd !

There is only one correct way to calculate position not sure why any manufacturer would decide to do it differently

 

[Brisel]

For various reasons we have numerous guidance systems on farm, Greenstar, Trimble, Claas, and Topcon ( all on Sim RTK).
We have decided that it is time we plotted all of our field edges accurately and plan to do this with the gator over the winter. My question is what system should I use in the gator to do this that can then be exported into all of the above systems. I have Gatekeeper so am happy to use that if it’s possible?

BB

Gatekeeper is a good central medium for this. Do you have the PF module?

 

[Banana Bar]

Gatekeeper is a good central medium for this. Do you have the PF module?

I do.

 

[Lincsman]

You would have thought wouldn’t you.
It’s not to do with the lines moving, it is how the lines are calculated that differs between the systems.
JD do it differently to other makes.
If you run an a-b line north-south from the equator heading up to the North Pole the JD ones would run exactly parallel all the way up. All other makes would get closer together as you get nearer to the pole. The same as the lines on longitude on a globe do. I remember going to a talk by a US farmer on CTF and it was messing up his CTF system as he had both makes on various bits of equipment.

So if you have a 3m drill and set off from the equator at spot on 3m, how much are you overlapping in scotland?

 

[Andy12345]

So if you have a 3m drill and set off from the equator at spot on 3m, how much are you overlapping in scotland?

Google Longitude and convergence

 

[Lincsman]

Google Longitude and convergence

Yes I understand but what is the overlap.. 9mm?

 

[B'o'B]

Yes I understand but what is the overlap.. 9mm?

1degree longitude at the equator is 111 km
1degree longitude around Scotlands latitude is around 55 km

So your 3 meter drill would be overlapping 3 x (55/111) = 1.52 meters. The further north or south you go the more extreme the effect.

 

[Clive]

1degree longitude at the equator is 111 km
1degree longitude around Scotlands latitude is around 55 km

So your 3 meter drill would be overlapping 3 x (55/111) = 1.52 meters. The further north or south you go the more extreme the effect.

Can’t imagine fields big enough for this to be a problem though !

 

[Lincsman]

1degree longitude at the equator is 111 km
1degree longitude around Scotlands latitude is around 55 km

So your 3 meter drill would be overlapping 3 x (55/111) = 1.52 meters. The further north or south you go the more extreme the effect.

Would be OK for broadcasting seed as the rate will automatically go up as you get closer to the Poles where weather conditions are harsher, do many farmers have fields that long/ my longest is only 1KM, what overlap would it have?

If you have a parallel system you are going to end up with a lot of short runs before you get the whole globe covered!

 

[B'o'B]

Can’t imagine fields big enough for this to be a problem though !

It was giving the guy who gave the talk problems with his CTF, so I flagged it up as a potential issue with mixing systems.
He was in America and did have big fields, he was also running a complex system of alternate drill/combine widths of maize and soya bean. So it had to work spot on. The effect is much more pronounced the nearer to poles you get.

 

[casemx 270]

We be mapped ours with a topcon screen on the sprayer but you can use any vehicle ie gater and driven on the boundary . Unfortunately the downside is not all systems talk the same language even with gatekeeper .We operate both Topcon and Trimble and found Topcon to be the best for doing boundary's obviously depending upon how update the screen and GPS package is .We tried using the drill boundary's but not very successful.

 

[Feldspar]

I could pull the boundaries in from the drill but I'm not happy they are accurate enough. I want true measurements of 1.25m from the top of ditch banks and 2m from hedge centres. I cannot hand on heart say we have this at the moment if anything we leave cross compliance strips too wide.

We have exactly this problem where despite saying to people to leave a comfortable cross compliance area people seem to love going slightly closer into the boundary than the last pass and things begin to creep. I almost thought about having a rule that outside runs round fields could only be done with RTK steering on because of this problem and the potential risk of losing BPS payments.

I found boundaries are a bit of a headache. The best way we found is to just take a tractor round at harvest time and drive the outside wheel round the edge of the field. This is complicated if you have a lot of overhanging trees because signal dropouts can ruin the recording and you have to start again. Topcon have a pause feature which allows you to pause whilst you go under big trees. I record a curved AB line as I drive round to give me a headland steering cure that exactly matches the boundary I've recorded.

A few of the really bad fields with more patchy signal I have had to do with something like the 12m rolls as it get the tractor far enough away from the trees that the signal doesn't drop out. Doing it with a sprayer or a drill is rubbish because getting the corners right is difficult and doing the two jobs at once either means rubbish mapping or rubbish drilling and often both.

 

[Brisel]

We have exactly this problem where despite saying to people to leave a comfortable cross compliance area people seem to love going slightly closer into the boundary than the last pass and things begin to creep. I almost thought about having a rule that outside runs round fields could only be done with RTK steering on because of this problem and the potential risk of losing BPS payments.

I found boundaries are a bit of a headache. The best way we found is to just take a tractor round at harvest time and drive the outside wheel round the edge of the field. This is complicated if you have a lot of overhanging trees because signal dropouts can ruin the recording and you have to start again. Topcon have a pause feature which allows you to pause whilst you go under big trees. I record a curved AB line as I drive round to give me a headland steering cure that exactly matches the boundary I've recorded.

A few of the really bad fields with more patchy signal I have had to do with something like the 12m rolls as it get the tractor far enough away from the trees that the signal doesn't drop out. Doing it with a sprayer or a drill is rubbish because getting the corners right is difficult and doing the two jobs at once either means rubbish mapping or rubbish drilling and often both.

Which signal are you losing? GPS or RTK? Can you remind me which form of RTK you use please? SIM or radio?