Having come to terms with how my hardware and software handles adjusted closed traverses and their sideshot observations, I'm hitting mental (and software) roadblocks when it comes to traverse stations with observations to more than one subsequent stations.
The attached drawing as an example, though any permutation thereof acceptable. Assumption made that the perimeter stations are not adequate to make the "interior" observations because of line of sight blockages. All work done with total station only, no GNSS.
Presently using Access, TBC and Civil3d. End game for design in Civil3d. I think my questions fall both in the general survey knowledge / specific software camps. The tutorials and manuals for TBC demonstrate traverses with only one path. Even in one tutorial where there are multiple paths, they do the demo choosing one route and ignore the other.
I *think* TBC only does traverse adj using compass method. In the manual, I see network analysis with least squares method, but it concentrates on GNSS data.
I'm know I'm scratching the surface on a new can of worms, and I apologize for lack of clarity. I'm trying to understand whether this is done in some fashion as a conventional traverse with extra steps, resection, other permutations, or network analysis. I've done a lot of searches, but a pointer in the right direction would be huge help. Much appreciated.
Mike,
I never use the traverse function of any software package. TBC has decent network processing capabilities, but it isn't very intuitive.
Prior to adjusting the network you need to set the error estimates in the project settings. If you have constraints (coordinates, elevations or azimuth values) fix them prior to adjusting as well. I still struggle to achieve unity without fiddling with scalars, but I am making progress.
Hope that helps get you started.
Good luck, Tom
I think *Star net* may be in your future.
We developed a concept, like this: "If you have good dicipline, and your angles and distances are good, you don't need adjustment software".
(There is some tongue in cheek there)
This works, with a limited amount of data. As your geometric designs become more complex, it becomes overwhelming.
But, the needed discipline, for good data, really never goes away.
Check out star net.
Kent Mc likes it, and he's probably right. I've never used it.
N
Thank guys -
I was thinking the traverse functions could be a bust because of how limited they were, how if you do one step wrong or out of order in the field, etc. they don't work. Also seems they can't incorporate resections, or back to my post heading, multiple directions.
I was going to ask about Starnet because of how often it's brought up here. I was bummed when looking in their supported hardware page they specifically put the S6 in the *not supported* category, which is basically what my SPS930 is. But if I can just import a point file, I don't know how it comes into play.
Ditto on the good data part, but fortunately, at this stage, that might be all I have going for me. I'm worried enough about making a mistake and that screwing me up or causing me confusion ahead, that I'm as careful as I think I can be.
-EDIT- I see off Starnet's page that Trimble makes an exporter to get data into Starnet, so hopefully that alleviates a limitation... All the import/export, though...
Unless you have immense networks to input, I would just manually type in the data. I still have the old DOS Starnet version 5 (I think) and it would take about 5 minutes to type in the data for a network of your size.
In the old days (before data collectors), I would even use Starnet to input open, unclosed traverses since I thought the input format was easier to use than my COGO software!
You are addressing and attempting to correct a combination of random errors, systematic errors, unknown errors, and personal errors.
No program will totally correct those errors, they will only resolve the issues into acceptable solutions.
Be sure and keep all the original raw data files and your first file of computed coords for future analysis when your skill have improved.
Gromaticus, I hear you. But what about all the side topo shots? Those would be getting adjusted along with all the controls, no? That's assuming that the topo observations are being done while at each station, at once, as opposed to getting all the controls done first, adjusting, and then going back out and getting the side shots.
Nate - you got me thinking - and I recall reading - when does the error/misclosure become factor enough that an adjustment is desirable, depending on the application and error tolerance. In my example site - posted elsewhere - I think it was something like 5000' over 6 corners and N and E was off about a hundredth, the Z a bit more.
On one hand, no adjustment - that misclosure, practically speaking in construction, and in my application, is relatively nothing.
And on the other hand - by the time that error makes it to the last point before closure, it's actually something a bit less than desirable.
I'm curious enough how well things work out on my non-adjusted points that I'll take a drive over and try it out. Resection throughout from far point to far point and see what happens.
Mike J., post: 373377, member: 11452 wrote: Having come to terms with how my hardware and software handles adjusted closed traverses and their sideshot observations, I'm hitting mental (and software) roadblocks when it comes to traverse stations with observations to more than one subsequent stations.
The attached drawing as an example, though any permutation thereof acceptable. Assumption made that the perimeter stations are not adequate to make the "interior" observations because of line of sight blockages. All work done with total station only, no GNSS.
Presently using Access, TBC and Civil3d. End game for design in Civil3d. I think my questions fall both in the general survey knowledge / specific software camps. The tutorials and manuals for TBC demonstrate traverses with only one path. Even in one tutorial where there are multiple paths, they do the demo choosing one route and ignore the other.
I *think* TBC only does traverse adj using compass method. In the manual, I see network analysis with least squares method, but it concentrates on GNSS data.
I'm know I'm scratching the surface on a new can of worms, and I apologize for lack of clarity. I'm trying to understand whether this is done in some fashion as a conventional traverse with extra steps, resection, other permutations, or network analysis. I've done a lot of searches, but a pointer in the right direction would be huge help. Much appreciated.
Take a look at this:
This is a link to the recording of the latest TBC Power hour, and deals specifically with these Topics. The next Power Hour is to deal with network adjustments including GPS, Total Station, and Level Data. The Times and dates are Wednesday May 25 at 8AM MDT and 4PM MDT.
If you look through your settings in TBC there is a link there to set up getting emails to let you know when these things are and register for them, or if you can't participate at those times, you can always watch the recording.
I am in the star*net camp.
start simple, manually input your traverse data, line by line straight from your field book.
even better, start with 2D data only. after you learn how it works, then add in 3D data as desired.
OK, so assuming you did Not take "real field notes" and all of it is in a data collector... there are modules that can read and import that stuff. I hope you collected Raw Measurement Data, not just some generated coordinates. If you have raw data and no software to convert then just type it in or cut and pase it.
If all you have is a coordinate dump you can reverse engineer it but that is laborious and error prone.
Side shots Can Not Be Adjusted, not really. Star*net will effectively first adjust your redundant data, then based on those resolved positions it will calculate the side-shot positions using angles and distances.
Nate is right.
As one of my best mentors said several decades ago "adjustments just spread the error around, it does not remove it".
There is no reason to Not adjust, but make sure that the accumulated error, if by chance it is really all in One Location, is that acceptable accuracy for your survey? It does happen!
Do test all of your theories, make it simple.
Mike J., post: 373383, member: 11452 wrote: Thank guys -
I was thinking the traverse functions could be a bust because of how limited they were, how if you do one step wrong or out of order in the field, etc. they don't work. Also seems they can't incorporate resections, or back to my post heading, multiple directions.I was going to ask about Starnet because of how often it's brought up here. I was bummed when looking in their supported hardware page they specifically put the S6 in the *not supported* category, which is basically what my SPS930 is. But if I can just import a point file, I don't know how it comes into play.
Ditto on the good data part, but fortunately, at this stage, that might be all I have going for me. I'm worried enough about making a mistake and that screwing me up or causing me confusion ahead, that I'm as careful as I think I can be.
-EDIT- I see off Starnet's page that Trimble makes an exporter to get data into Starnet, so hopefully that alleviates a limitation... All the import/export, though...
We already have the old StarTDS converter so I do a custom export to TDS RW5 on the Trimble controller (in Access) then convert that to StarNet DAT on my desktop or laptop computer. You get the RW5 style sheet from Trimble for free and put it in the appropriate folder on the Controller.
Mike J., post: 373377, member: 11452 wrote: Having come to terms with how my hardware and software handles adjusted closed traverses and their sideshot observations, I'm hitting mental (and software) roadblocks when it comes to traverse stations with observations to more than one subsequent stations.
The attached drawing as an example, though any permutation thereof acceptable. Assumption made that the perimeter stations are not adequate to make the "interior" observations because of line of sight blockages. All work done with total station only, no GNSS.
Presently using Access, TBC and Civil3d. End game for design in Civil3d. I think my questions fall both in the general survey knowledge / specific software camps. The tutorials and manuals for TBC demonstrate traverses with only one path. Even in one tutorial where there are multiple paths, they do the demo choosing one route and ignore the other.
I *think* TBC only does traverse adj using compass method. In the manual, I see network analysis with least squares method, but it concentrates on GNSS data.
I'm know I'm scratching the surface on a new can of worms, and I apologize for lack of clarity. I'm trying to understand whether this is done in some fashion as a conventional traverse with extra steps, resection, other permutations, or network analysis. I've done a lot of searches, but a pointer in the right direction would be huge help. Much appreciated.
Mike J.:
Assuming you can convert the files, the demo version of Star*net (with a 10 point limitation) will work well for this network. Redundancy is key, and the more you have, the better the results. You don't say whether time is money, but for maximum redundancy, I'd run ABCDEA as you have; then do ABFA, AFGDEA, BCGFG, and CDGC, all as separate traverses, making observations back to the POB in each case.
Lot of work, but you'd have a ton of redundancy. Adjust and output the adjusted coordinate file into Civil3d.
StarNet does this is the sort of thing well. I am told that TBC will readily handle it, too. Either way it's a job for least squares.
I know that AutoCAD Civil 3D has a least squares analysis program. Why not learn to use that and save some money.
People on this forum are fond of one particular software and push for that as a solution. The Principles of Least Squares is a numerical method and is not copyrighted by one particular brand of software.
There are bound to be some tutorials on You Tube if you can't attend a class. It just seems foolish to go out and buy software that you already have.
In any case I use and recommend Least Squares for survey network analysis.
not my real name, post: 373404, member: 8199 wrote:
It just seems foolish to go out and buy software that you already have.
Not necessarily. I've used the LSA modules in Traverse PC, the Carlson Survey (demo), and Microsurvey CAD (demo), as well as some "do it long hand" routines. Hands down, Star*net is the most straightforward, easy to use (even for complex networks). This counts for a lot when you're just trying to clean up your observations, ridding them of blunders, (not that others make nearly so many as I do of course).
IMHO it really does stand above the rest.
Mark Mayer, post: 373402, member: 424 wrote: I am told that TBC will readily handle it, too.
Assuming that you have the adjustment module, of course. And yes, Civil3d will do LS adjustments of terrestrial data.
Star*Net is your friend for multiple loops/cross-ties in a control network whether small or large. Very robust program.
I've used Starnet since DOS3 versions on 5" floppies. Typing in data for networks that are on the order of construction control is a no brainer. My data collector is a pencil. Your diagram is classic LSA fodder. Once you go Starnet there's no turning back.
Wow - seriously, thank you to everyone that chimed in. You should replace the "like" button with "donate now." I d/l starnet and put everything in manually. Since you guys all helped me out I'll post what came out. I think I have a good long road to figuring out what the result info means, whether the field work is "thumbs up" or "man, what an idiot." Essentially feeding myself to the wolves for your amusement and delight.
To clarify: Point "1" was my known backsight, and keyed in coordinate is at "2." I didn't use "1" as part of the traverse because it's line of sight from "9," hence the adjacent point "11" that let me close to POB at "2."
There was a sideshot at each station that I omitted, hence the skipping station numbers.
Instrument and centering errors are probably iffy.
It's just the earlier perimeter traverse w/o any "intermediate" stations or loops.
There is a converter for almost every type of raw data file imbedded in StarNet. The are all activated during the 10 day demo period. You need to export your raw data to .dc format in Access, then StarNet will convert that to the .dat format.
