Carlson Surveyor+ GPS

Any civil engineering people here who have used this piece of equipment or something similar? I looking to rent a unit for a few days to locate 70+ well points on a 4.5 acre industrial site.

I've used differential GPS a fair bit, although not that particular software/hardware.

Must work about similar right?

My background is 'old school' meaning I'm a former transitman. Got a Schneider TT700 I bought used that we utilize for all our internal surveying needs. Now I'm not doing an A-2 survey so knat's ass accuracy is not required. I'm surveying in 70-100 well points on a fairly open (no trees) industrial site in and around process buildings, labs, office buildings and several tank farms.

Given my limited background (two years full-time as a transitman for a field survey crew and six years on an "as needed" basis) how difficult do you think it would be for me to pick up the nuances of operating a GPS rig like the Carlson Surveyor? If I can capture the location of all the well points within a couple of inches I'm assuming I can download this info (as an ASCII text file) and get it into AutoCAD. Is that a fair assumption on my part or am I missing a key piece of information?

It all depends ReMark.

Do you know what formats the Carlson can output?

P.S. You might get some better input in MAP3D.

At the moment all I know is that it can do an ASCII dump. What else it can do in terms of communicating with another program I can not say. I do not want to buy any software since I am only renting the equipment for 3 to 5 days. Wish I could buy it though. The quoted price is $16,500. Spare change anyone? Just throw it my way.

Mark, are you setting out the locations of the well points or surveying (measuring - US term) the locations of existing well points? Setting out is somewhat more complicated than surveying the points with GPS (GNSS) equipment. We use Trimble and Leica GNSS equipment and it is relatively easy to survey the points in, and although I have no experience with Carlson instruments I cannot believe that they would be any different.

The important thing to do is negotiate as part of the hire charge a minimum of one hours instruction with the instrument so that you know how to use it specifically to meet your needs AND how to format the ASCII output in the way that you want it, I would suggest in the coordinate system you will be using. The satellite systems that can be used in the main are GPS (US satellites) and GLONASS (Russian satellites). The receiver will be able to pick up either GPS or GPS and GLONASS, the results are so much better when you can pick up both systems, its quicker, more accurate and you can operate much closer to buildings and other obstructions.

GNSS equipment requires line of sight vision with the satellites so working close to buildings can be troublesome, but with your experience as a surveyor you would be able to work around that. With just GPS you can, on a good day get accuracy of a couple of inches but on a bad day a couple of feet. With GPS and GLONASS you can, on a good day get half inch accuracy.

Using the instrument is easy you just press the button, wait and record. Its the setting up and output of the data that makes the difference. When I look at some of the people here who use these instruments, I don't think you will have a problem.

Just as an indication of what you can do, we easily survey in 1500 points per day in open locations using our GNSS instruments (with GPS and GLONASS).

Best of luck and have fun.

I was talking about moving your question to the MAP3D forum, not purchasing the software.

I was talking about moving your question to the MAP3D forum, not purchasing the software.

or Civil 3D, that's where the surveyors are

The chat section is fine by me.

I will be surveying in the location of recently installed monitoring wells. Many of them had to be relocated due to the presence of u.g. utilities so the map that we got from the hydrogeologic company is no longer accurate and our environmental engineer wants fairly accurate locations. If it is within 2" of its true location that's fine by me. I originally thought I'd set up a baseline and use stadia to locate all the wells but this site is not conducive to that type of survey for a variety of reasons.

Why not simply pay a surveyor to do the job for you? By the time you take into account the cost of hiring the equipment, learning how to use it and going and doing it yourself (when you could be working on something else) you are probably not saving a whole lot of money. Surveying 100 well points on an industrial site shouldn't take more than half a day total at most (i.e. say $1600 for the data in a file format of your choice).

I'm not a surveyor myself although I can use the GPS and total stations etc after being shown how to use them by our surveyors. I rarely use them though as it is easier to just get them to go get the data and send it my way. Picking up points is one thing, although as Tyke said above, setting out is another.

The cost for renting the equipment for a day is $400. Training is billed at $125 per hour. If the GPS is rented for 3 to 5 days the cost is $995.

We had a surveyor do some work for us a few years ago. He was one of two surveyors who have done work for the company over the past 30 years. Upon completion of the project he submitted what he called an A-2 survey map. I reviewed it. It had so many errors in it that I wrote a letter to the president of the company stating in effect that the map was not to the standards of an A-2 survey as I understood them to be and was virtually worthless to us.

What sort of deposit do they require you to put down for it though?

Is an 'A-2 survey map' a registrable plan in the US, or is it more of a sketch only issued to the client?

All I need is a company credit card to secure the GPS unit.

An A-2 survey is certified/stamped/signed as to being substantially correct. It is a high level survey. I've only done two of these types myself under the guidance of a registered land surveyor. They are very precise.

You should try to PM Murph_Map, he should have some insight on these issues. I am moving this to Civil3D forum.

You should try to PM Murph_Map, he should have some insight on these issues. I am moving this to Civil3D forum.

I'm following the thread now that I'm here. (day off and can play on the internet)

The cost for renting the equipment for a day is $400. Training is billed at $125 per hour. If the GPS is rented for 3 to 5 days the cost is $995.

 

We had a surveyor do some work for us a few years ago. He was one of two surveyors who have done work for the company over the past 30 years. Upon completion of the project he submitted what he called an A-2 survey map. I reviewed it. It had so many errors in it that I wrote a letter to the president of the company stating in effect that the map was not to the standards of an A-2 survey as I understood them to be and was virtually worthless to us.

I had to hire a Leica GNSS instrument while one of ours was in the workshop and the daily rate was just under $150 and I negotiated a 50% discount because we are long standing customer. I don't know what the rates are in the US but I'd do a check with some other companies to see what their prices are. Check out a weekly hire charge, they are sometimes cheaper as hiring for four days. The hourly rate for training is about the same as we pay here.

Haven't used the Carlson units but a few others types over the years. Once you GPS the points and save to an ANSI text file you can use a few different mrthods to bring those points into AutoCAD. The simple way is with the Multi command and cut/paste the points from the txt file. Another method is write a simple lisp to read the txt file and insert a block.

The one issue you may need to watch for is the coordinate system you use to collect the points (Lat/Lon, State Plane etc) If this is a one time job then you may want to download the trial version of MAP3D and use the tools in there to import the file as standard AutoCAD objects (points or blocks). I'm bet the GPS unit can save the points to E$RI shape format that MAP3D can use.

Companies that sell, rent and service survey equipment are far and few between. I had to drive 50 miles to find one. Fortunately it was on my way home.

The coordinate system used is the Connecticut State Plane System. I'm familiar with it having also worked for a consulting engineering company doing highway and railroad design work.

All I need to do with these well point locations is get them into the cad drawing of our site plan. Nothing fancy. Heck, I don't even need elevations but I get them just the same with this equipment. And as I may have mentioned I need to GPS locate at least two fixed points that correspond with something on our site plan. Normally I'd used the iron pins typically installed as property corners but this company has a nasty habit of destroying them. I even had one contractor purposely remove three pins at the request of the company president on an adjacent parcel of land we own. I had staked out a new fence line that had jogs in it that corresponded to the jogs in the property line. The contractor was told to ignore the jogs and run the fence in a straight line from point "A" to point "B". I was livid when I saw what was done (the work happened over a weekend). A quick walk around the perimeter of the property the wells are located on turned up not a single I.P. left. I know for a fact that there were at least two that I located in the past. In their place are fence posts now.

Like Murph_Map stated, worse case scenario you will just need to do a trial of Civil3D.

Just keep in mind that GPS equipment is a tool. It's only as good as the person using it.

Since you aren't interested in incredibly high precision, and you are using a common coordinate system like State Plane, you might be OK renting some equipment and doing it yourself. Especially if you take care, and also tie down enough known points as checks, so you can confirm that everything seems to be working OK.

But there's actually quite a lot involved in learning GPS... It really is not just "push a button, the software does the rest". That might happen if you're lucky. But there's lots of ways to get yourself into trouble, if you don't understand what's going on and how all this stuff is working.

If your existing Surveyor is not giving you satisfactory results, then a safer course of action would be to find a different Surveyor. But if you decide to proceed on your own, just use caution and lots of checks. You'll only have yourself to blame if anything goes wrong.