Hi Guys
Im not a surveyor but im involved in a contract that requires some manholes over about 50 acres to be "mapped". We have to gather the data to report the GPS location of the manholes. The data will need to be added to a ESRI – Geodatabase.
The contract requires post processing to ensure accuracy. We have been told that the GEO XH can work for this application.
My questions are:
(1) Has anyone out there used the GEO XH?
(2) Is it easy to operate and collect data for a surveyor with a few years of experience?
(3) How much time at each manhole does it take to collect/label the data? 1 minute? 15 minutes? more? How about when downloading the data?
(4) Does the software do the post-processing or does that require any physical or desktop (computer) labor? Does it take a lot of time to do post-processing?
I appreciate any and all input.
Thanks
Surveying Related
Sorry, but when things need to be located, licensed surveyors and their staffs are the appropriate solution.
Mr. Time,
Just crash your car near each manhole and have the local PD map them.
JA, PLS Socal
Just a couple thoughts.
1. "The contract requires post processing to ensure accuracy." If the client is dictating your procedures I'd walk away from the job.
2. I'm assuming that you don't have an XH. I would suggest that you take a look at the cost of this setup. Figure about 11 grand plus for a basic unit (Hardware and software). Add another 3 grand for an external antenna/cord/pole/legs/bracket.
3. If your database is set up properly, the data collection should be fairly straight forward. The trick is getting the database set up.
4. Depending where you are at, if there are no base stations in your area, post processing might not improve your data set significantly. And you are still not going to be able to claim better then 1 meter horizontally and double that vertically.
If you really want to go this route, you really need to talk to your local Trimble dealer to get a realistic picture of what you need.
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> My questions are:
> (1) Has anyone out there used the GEO XH?
Yes I have probably over a thousand hours over the past three years using a geoxh, proxh, and proxrt. They are all good units for what they do. On the geoxh and proxh the zephyr antenna will help your accuracy a lot. 90% of the time I get post processed sub foot locations but that depends on your proximity to base stations. I never really see post processed worse than a meter even in sparse data areas.
> (2) Is it easy to operate and collect data for a surveyor with a few years of experience?
Yes. When I first started using them I had never done any surveying not did I have anyone show me how. They are easy to use if you have a good understanding of how positioning systems. Don't get me wrong they are not like a garmin in your car but they are not brain surgery either.
> (3) How much time at each manhole does it take to collect/label the data? 1 minute? 15 minutes? more? How about when downloading the data?
We observe for two minutes when first opening a file or after we lose satellite lock. Once we are rolling we measure for ten seconds at each point. It is not uncommon for us to collect 3-400 points per day. Downloading takes maybe five minutes.
> (4) Does the software do the post-processing or does that require any physical or desktop (computer) labor? Does it take a lot of time to do post-processing?
Post processing is done in pathfinder office on your laptop or PC It takes a while depending on how many points you have. A couple hours is not uncommon for a large data set. Smaller things happen much quicker.
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> I appreciate any and all input.
> Thanks
