I am serving on a committee to begin researching guidlines for GPS, both static and RTK for use in boundary surveys. These recommendations will be considered by our state's Regulatory body for incorporation into our minimum standards.
I would appreciate any links to your state's rules and regulations regarding the use of GPS in boundary surveying.
We are just now starting our research, and exploring this subject.
Thanks in advance
GPS/RTK Guidelimes
~Lurking~
I'll be watching this thread.
Nate
It would probably be the same as conventional measurement.
We are bound to be accurate to whatever our state requires whether we show a measurement of 5.28ft or 5,280ft.
I have never heard of any requirement of how we acquire our measurements, as long as the results fall within a certain quality of accruacy.
I wish you luck. Just about any guidelines you publish will be out of date before they are printed due to advances in equipment and software. A quick search of the internet will reveal many outdated examples. That being said, there is still a need for guidelines. I'm just saying be prepared to keep them updated in a timely fashion.
You use it badly, you get bad results, which is exactly the same as a total station, data collector, transit, or steel tape. I just don't see a need for a separate category or standards for GPS/RTK.
Even if there is no obligation for guidance notes in my country (Greece), I usually follow the uk's survey association's guidance.
As quoted from the NSPS:
"The surveying methods used by the professional surveyor (Surveyor) vary with the purpose of survey to be made and the equipment available. Also, surveying technology is constantly changing, therefore a national standard for a particular type or class of survey cannot specify methods or equipment lest it become obsolete even before it is adopted. A modern standard must be limited to a general description of the survey along with reporting and accuracy requirements. A national survey standard should tell (1) what the survey is to accomplish and what items are to be investigated, (2) how the results are to be reported, and (3) how accurate the results are to be.
It is the responsibility of the Surveyor to select the appropriate procedures and equipment to obtain the accuracy required by the standard. In other words, the surveyor is expected to design a survey measurement specification that will obtain the required accuracy. A standard should not specify surveying procedures but only results."
Couldn't have said it better myself
The one thing I would make sure y'all include in the guidelines is redundancy. RTK observations always and static observations sometimes give imprecise positions when only performed once.
Try these from CT, mostly written by Tom Meyer a professor at UCONN who really knows his stuff.
http://ctsurveyors.org/wp-content/uploads/2010/12/GNSS_20080626_online.pdf
T.W.
> I am serving on a committee to begin researching guidlines for GPS, both static and RTK for use in boundary surveys. These recommendations will be considered by our state's Regulatory body for incorporation into our minimum standards.
>
> I would appreciate any links to your state's rules and regulations regarding the use of GPS in boundary surveying.
>
> We are just now starting our research, and exploring this subject.
>
> Thanks in advance
Wow, what a dangerous and foolish road to travel down. Good luck. I hope the powers that be soon come to their senses.
I agree with what bmeyers posted.
Do you have similar regulations for other methods of measurement (chaining, pacing, stadia, solar compass, total station, robotic, etc.)? If so, they should be easy to modify and adopt. If not, why not? Will you adequately address accuracy vs. precision?
Maybe you should include regulations on what types of shovels and metal detectors are acceptable for boundary surveying, and include complete outlines and regulations of their proper and acceptable uses????
Ditto to Brian. He stated it much better than I would have.
Pablo B-)
> As quoted from the NSPS:
>
> "The surveying methods used by the professional surveyor (Surveyor) vary with the purpose of survey to be made and the equipment available. Also, surveying technology is constantly changing, therefore a national standard for a particular type or class of survey cannot specify methods or equipment lest it become obsolete even before it is adopted. A modern standard must be limited to a general description of the survey along with reporting and accuracy requirements. A national survey standard should tell (1) what the survey is to accomplish and what items are to be investigated, (2) how the results are to be reported, and (3) how accurate the results are to be.
> It is the responsibility of the Surveyor to select the appropriate procedures and equipment to obtain the accuracy required by the standard. In other words, the surveyor is expected to design a survey measurement specification that will obtain the required accuracy. A standard should not specify surveying procedures but only results."
>
> Couldn't have said it better myself
:good: :good: :good: :good: 🙂
Specify realistic accuracy objectives not equipment and procedures.
:good:
Amen, brother.
Pretty Much Positional Tolerance And Be Able To Prove It
The above covers equipment, technique and redundancy.
Specific details can vary with the knowledge of the operator, receivers and software used. I may be able to do something with my software that cannot be matched by others with their software emulating my methods. Yet equal results can be had from that software by different techniques. That requires a solid understanding of the particular software capabilities by the operator. I have been able to get results for others that they could not initially get. Sometimes it required observation editing, sometimes it was just getting the software settings right, i.e. elevation mask, etc. sometimes it was just that my software is different and sometimes more data was required. More data does not necessarily returning to the field for more observations. I have resolved positions that were bad because obstructions reduced the commonality of satellites. By bringing in multiple CORS data and separately solving each field position there was enough independent commonality to meet project precision. Even with as much as I know, I have been stumped a few times. I also know that even my software cannot get the same results when the order of work procedures is changed.
Give me different software and I would be at a loss until I figured it all out, some by trial and error as well as by intensive reading.
All in all there is no cookbook for the ignorant to make up for knowledge and experience. They will be able to do exactly as you say and not get good results, worst yet they will not know they have poor results.
When you think you have it right send me a copy for review. I learned a long time ago when sitting on Planning Boards that it was much easier to be critical than to be right.
Paul in PA
If the committee is unwilling to fully explore the task I agree it is dangerous. Sitting down to determine what may address the willful ignorance of many in our Profession is not at all foolish.
It would be great to see policy that required us to say what we did and what the results are. When I found myself at the PLS level, that was the real eye-opener. I suddenly had to quantify and communicate my results to people I'd never met. It made me a better Surveyor. That should be the goal of any Survey related policy.
My .02...
*Positional tolerances, both local to the project and if applicable also to NAD83.
*Full and properly stated metadata.
*Redundancy of measurements, with a recommendation that GPS measurements include some separated by hours.
Let them use any technique that they can document works.
Having kind of read through the above posts, I can only agree with them all. To set a standard for any utilization of any type of equipment is a slippery slope at best. Disaster in the making at the worst.
GPS is no different than a robot or a T2 or a 15 second Gurley transit with a steel tape or the shovel & hammer in your truck. Tools. Nothing more, nothing less. Don't matter if it's raining, snowing, windy, hot or you have a hangover. The bottom line is you get it right.
That is the standard.
> If the committee is unwilling to fully explore the task I agree it is dangerous.
How are we going to fully explore each and every potential task and use of GPS in boundary surveying? Who is going to decide the minimum session length for each and every use? What are the guidelines for processing using each and every software package? What software is acceptable or not? What are the specific guidelines for manipulating the data and/or decimating session data for each and every potential use?
How about, instead of spending years trying to write "minimum technical standards" for measuring that would (unsuccessfully) cover every possible circumstance, scenario, and potential use of a tool (are we going to do this for every "tool" in our truck and office?) , we instead focus on what really counts in boundary determination - the proper gathering, use, and interpretation of the information, and the proper application of the law?
Show me one court decision in which the determination of the boundary on the ground turned specifically on how GPS (or any other measuring tool) was used.
> Sitting down to determine what may address the willful ignorance of many in our Profession is not at all foolish.
I wholeheartedly agree. But perhaps this should be addressed by the members of our profession. How about a profession-wide willingness to remove the "willfully ignorant" from our profession? Believe it or not, there are processes for doing so already in place, if only "politics" could stay out of it -- yea, I know, wishful thinking.........
> It would be great to see policy that required us to say what we did and what the results are.
There already is, and it is already in place!!!!!! It is called a professional standard of care, which cannot, by definition, be codified! Maybe we ought to stop trying to do what is impossible and start doing what we can and ought to do. Maybe understanding this principle is what needs to be focused on?
> When I found myself at the PLS level, that was the real eye-opener. I suddenly had to quantify and communicate my results to people I'd never met. It made me a better Surveyor. That should be the goal of any Survey related policy.
> My .02...
Great, that is what being a professional is all about. Learning, applying, studying, teaching, learning, applying, studying, adapting .....................
Lets be professionals, not technicians or tradesmen. Any monkey can be trained to follow a checklist, but professional surveyors do far more (or at least should) than follow checklists. No two boundary situations/solutions are exactly alike, lets quit trying to force them to be.
Just curious, do any of the other regulated design professionals (engineers, architects, landscape architects, etc.) have a set of codified minimum standards?
If not, then, in my opinion, the only legitimate position for the state society to take on minimum standards is to fight for their abolition.
