Layout a simple fence line?

@steve1428 , what you are looking for is COGO, or COordinate GeOmetry.

Most paid Data Collector Apps have COGO functions.
There may very well be freeware apps with it also.

You would establish the bearing with the 2 endpoints of a straight section, then create points @12’ along that bearing.

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yes they do it’s called FieldGenius, it’s a lot of money
there are others.
they won’t even sell to you unless you’re a surveyor, they’v’e got a little gps exclusion club

Go to chatgpt.com and type in the following prompt:

I have two end points with known lat/long coordinates. Write a python program that prints points at 12 foot intervals on the line between the two points.

Some years ago, I built a F9P rtk base-rover pair with an arduino on the rover that calculated and displayed bearing and distance from the last reference point I had recorded.

Something like this would work nicely for the OP to lay out a series of fence posts in a straight line from an origin point.

For example, in the photo below, the rover is 92.51 feet N85.40°W from the reference point I had set.

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very nice
SW maps has the staking function that directs you to the next location,

when i have some time i’ll play with the COGO thing, I think that’s the way to create these waypoints along the fence line and just upload a kml file to sw maps

I did a very similar thing a few years ago with the Ublox C94-M8P base-rover pair.

The two-component kit is entirely self contained, with integrated radios so they communicate out of the box over many km, line of sight.

Once the base “survey-in” was complete, relative positioning accuracy was stable and as advertised (comprehensive tests and review). Setup and operating instructions were very clear.

Still a few kits left at USD 448:

i’ve spent a thousand bucks and can’t even get an autonomous base setup

Great write-up!

I just followed this tutorial Setting up a Rover Base RTK System - SparkFun Learn, and used the SF arduino libraries to pull in the data and my own amateur coding skills to pipe it onto a little OLED screen

I think the F9P itself also sent the data over USB to SWMaps, as I don’t recall coding the arduino to do that.

I highly recommend that tutorial.

i can get it to work with known coordinates plugged in.

this exercise of collecting raw data and converting it to rinex just doesn’t work with the app i’m using and i don’t think i can get at the lg290p through the usb to use qgnss app.

Ho rispolverato i libri di geometria piana…
…ricordo che qualche pigro topografo giocava con G_Earth e che in effetti dava risultati
soddisfacenti,senza far storcere il naso ai geometri ortodossi.

The technique used is to convert the WGS84 coordinates into UTM plane coordinates.
You have to pay attention to the zone you use and stay within it.Google Earth Pro can do it.
E.g. U have 34,801472°N , 114,083487°W into search_bar as placemark
then go in tools_options and
immagine
then R_click on the placemark and in properties can see UTM coordinate.


take note 766818.31 m E ; 3854905.21 m N are the plane coord. (to use in a cartesian p.in meters)
the formula to calculate the distance between two points is:
d = √((x2 - x1)² + (y2 - y1)²) where x=easting & y=northing
need the Unit_vector as ( (x2 - x1) / d, (y2 - y1) / d )
and the Displacement_vector of n meters as n( (x2 - x1) / d, (y2 - y1) / d )
so need to add the n*Unit_vector couple to the first point:
e.g. for 100m distance ,if the couple of Unit_vector is (0.69,0.71) will be
(x1 + 69,y1 + 71) if the bearing y=Northing go to north…(as in A)

let say second point has 766947.00 m E ; 3850370.00 m N
need distance:

d=766947.00-766818.31= (128.69)²=16561.1161
3850370.00-3854905.21=(-4535.21)²=20568129.7441
16561.1161+20568129.7441=√20584690.8602=4537.03547046m

now Unit_vector:
U_v_x=766947.00-766818.31=(128.69)/4537.03547046=0.02836433632
U_v_y=3850370.00-3854905.21=(-4535.21)/4537.03547046=-0.99959765127
U_v=[|0.02836433632 , 0.99959765127|] ( | mean absolute value)
if U see the


second point (B) has x positive and y negative and the vector_direction coordinate are (x,-y)
instead if the second point is in C it has (-x,-y) and so on
So,take a point at 150m…
150 (0.02836433632 , 0.99959765127) → |( ±4.254650448 , ±149.939647691)|
so
766818.31+4.254650448=766822.56465 for x
3854905.21 - 149.939647691=3854755.27035 for y
P150m has 766822.56465 m E ; 3854755.27035 m N
that in WGS84 is


now U can mark points and convert into kml or gpx…for other apps.
A programmer would be needed for the auto-calculations.

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I spent $400 for my C94-M8P kit and was up and running in less than an hour, following the instructions. However, survey-in can take many hours to get a decent base location.

BTW it comes with a pair of active antennas with handy ground planes.

i’m exaggerating, two good antennas were couple hun, and the boards were around 200 each, cables, etc, shipping, it adds up

yes i saw that on a land survey the other day, “NAD83”
I’m trying to learn this.
but the property line itself seems to be the same long and lat as indicated on the county GIS maps.
I think the GIS is in the same system as the GPS receiver.