I’m wondering if anybody has come across a smart phone application that has the capability of importing a Cad file with GPS co-ordinates from a professional surveyor, and then using that file to help one locate the building corners for laying out the foundation footings on a new construction building? I’m thinking there must be an app out there that uses the GPS capabilities of a smart phone to basically guide you to within a foot or so of each building corner using the survey file as a reference.
If anybody knows of such an application, please share!!
Replies
GPS - Cad download
Stoller B
Not sure these companies have a smart phone App yet but I would look at the following websites:
Leica Geosystems
Topcon Positioniing Systems
Trimble Navigation
these are the leaders in surveying layout and may be of some help.
regards,
Mike
PLS
Mike
Nice of you to show up.
hope all is well.
Accuracy??
Do consider accuracy.
Most cellphone GPS chipsets will only give you a three meter position a certain percentage of the time. Is that accurate enough? If you add an external GPS, you can get down to one meter. If there are trees (or other structures) in the area that could create multi-path reflection, your errors can rise dramatically.
A dedicated GPS receiver will be more accurate than a smarphone GPS simply because the priority of a true GPS receiver is positional accuracy. The priority of a smartphone GPS-capable chipset is to minimize power consumprion. Positional accuracy is further down the list with smartphones.
The accuracy of any GPS device can also shift over time. ie, were you to turn the device on, allow it to center, then leave it in a spot and log "location versus time" over the course of a day? The CEP could shift as the satellites overhead shift.
So...GPS? Good stuff. But it might not be good enough for siting a building, especially if the location and/or setbacks are crucial.
Jim
I'm glad the poster concluded that the phone isn't the way to go.
We drove to Columbus, Oh. last yr and on Joyce's "nice" phone-we were driving in a reservoir a 1/2 mile to the east..............
and then there's those folks who tried to drive over to an island-there was no bridge.
I'd give it a go for the search party to start their rescue, but other than that-shoot the pins and lay it out by hand. Long tapes and Pythagorus. Batter boards and strings.
Hope all is well with you and the family-it's time for baseball.
You need survey grade accuracy.
You need survey grade accuracy to set corners for a building, (If you are out in the boonies, and own enough property you might not), you wouldn't want to inadvertantly violate setbacks, etc.
The survey gear is accurate to the millimeter, if you have a site beacon to boos things.
Your phone is accurate to within three to ten meters, depending on conditions, etc.
Accuracy
I just pinned the corners of our building with the surveyor, and discussed this with him. He verified Mongo's and PLSLaser's comments, that a smart phone's GPS is supposed to be only accurate to within 4-6 metres, but under ideal conditions is accurate to within 3m. Definitely not accurate enough for initial excavation, especially where I am as often we have to break or blast rock to get into the ground, so overdigging by 3m in each direction is not an option. Anyway, I can keep dreaming! Thanks for your responses.