I am looking for a good gps android app for doing boundary retracement. Locate a position on first found corner and then enter direction and distance to establish waypoints to navigate through the woods.
This Content Originally Published by a land surveyor to Land Surveyors United Network
I am not planning on producing a boundary survey. It is only for finding monumentation and reference trees on the side of a mountain.
Please use any suitable app, if you are looking for accuracy. the difference as per actuals may vary by even some metres.
A Murali babu
If you use a data collector that has an integrated gps (L1), you can use your data collection program to do that. Store the known property corner you found, and translate/rotate calculated property corners over that, and use the stake out function to get you close for recon. I run boundary retracements the same way while traversing, but if your just doing recon or trying to get close I think that would work fine.
I hope you are just using that to get in the general vicinity to search for monuments. You can do that with about any hand held GPS, or a compass & tape. I think I'm going to get ill if I hear "app" one more time. Technology is great but today's generation can't pour a cup of coffee without a app stuck somewhere the sun doesn't shine.
That reminds me of the two old farts sitting on a park bench. One says to the other, "Sir, did you know you have a suppository in your ear?" The reply was, "Never mind that, where did I put my hearing aid?"
I am not planning on producing a boundary survey. It is only for finding monuments and reference trees on the side of a mountain for the AT trail monitor program. My pacing is pretty tight in the flat lands but is quite sloppy hopping over brush on the side of a mountain. My hand held GPS is starting to fail I figure if the cell phone has a GPS use it, the down side is cell phone battery probably won't last all day.
Thank you for the input.
Just remember, a computer's attention span is only as long as it's power cord.
if its a recent survey by the National Forest then they can be easy to find with 3 very well marked witness trees... what state are you stationed in?
I feel ya Charlie on the app thing... My insurance agent thinks you only need a cell phone to survey land... I will give Google maps credit... it seems to be well within 20 foot accurate... I was amazed to be very far out and had decent cell coverage when i stepped up to a dock on a pond and the blue icon was floating correctly on their aerial image...
I'm with Charlie on this one ... apps aren't (yet) the answer to everything.
The solution here pivots on GPS accuracy. Any app will be leveraging the GPS inside your phone which will be similar to your handheld GPS but the handheld (use Garmin) is a dedicated tool for doing exactly what you are trying to do (within certain accuracies) and like you indicated, will last all day and more importantly will not require a cell connection .. ie just because you can see yourself on an image in any app you may find, doesn't mean that you are actually at that spot. A newer handheld Garmin GPS will have the benefit of being able to leverage more satellites and WAAS which typically will give you more reliable accuracy.
It sounds to me that you don't have access to GIS/GNSS (sub yard) like the Trimble suggested previously or Survey grade (sub inch) GPS units so that would mean I'd suggest a newer handheld Garmin GPS and expect accuracy along a line to be within a couple yards of the line. If you need better accuracy, you need better gear ... and someone who knows how to run it along with the knowledge of the things that can go wrong.
Assuming only what you've told us so far: Next is to know where the line you are trying to follow actually is. I'm Canadian but I believe that what I'm going to tell you is universal: "the pins in the ground govern" so find the pins (monuments) and get as good of a GPS location on them as possible ... your GPS will have an averaging capability, use it. (There's another way that I use that saves a lot of time but I won't explain that here). You want the line as accurate as possible as you will be varying a couple yards from that remember. Stand on one of the monuments and navigate to the other. There is a function in the GPS that allows you to set on the map screen that will show you how far off of that straight line "cross track error" I believe that this function has different names in different vintages of GPS ... this also allows you to weave your trail around in the bush and check proximity to that line once in a while. If you are a computer guy: Another way to draw the line is to create waypoints at the monuments and put them into MapSource or BaseCamp (Garmin software) and transfer the line to your GPS.
So ... too much information?
A realestate agent I work for quite often that deals primarily with rural acreage has one of those apps. It usually will get you close enough where you can see a corner if it is visible. I once used a loran to navigate my boat. I now have a commercial grade gps but it isn't any better than loran. It is much more user friendly. None of the above were intended to produce survey grade results but they generally do what they were designed to do. The trouble with a GPS signal in the woods, except maybe if you are working with RTK from a good BASE, is you can never be sure how good your results are. Even then it's very problematic. I still recall my "Horror Story" experience with the engineer that thought he (mostly me) could survey 28,000 acres of swamp & alligators with numerous out parcels in a couple weeks with a GPS. A large portion of it was only accessible in a drought. There were plenty of cotton mouth water moccasins & beavers. Never did see any wild hogs while surveying but you could hear them & they weren't very far away & you could see where the big boars had debarked the base of trees with their tusks. Did see a few along side of the road while driving.
Everyone has the classic horror story. I had one manager that decided we could do boundary, trees and topo, on a wooded parcel at the rate of 15 acres a day. I told him I could get all 60 acres done before lunch tomorrow.
I hope he didn't bid the job thinking it could be done in 4 days. And then 4 weeks later we had trees and topo lines on the map. I could only imagine how many trees and how steep the property was. Did you punch him?