3-Point Resection (by distance)

A good least squares program should handle that. I know Star*Net does, I have not used any others to try.

I do the centroid thingy also. Doesn't take long to do and is typically as good, when you're done, as the coordinates you're starting from. Strength of figure is important.

Can't you just draw it in Autocad?

Maybe not so handy if you've got a lot of them to do.

Old TDS 48 does it

I seldom see simple little programs for such a task any more. I have a lot of tools at my fingertips for this type of "resection". Are you talking for your computer? Most all cogo softwares should be able to do this, and as someone said, you could do it in AutoCAD. I am sure there are softwares for programmable calculators as well that can do this.

The DOS COGO I always used before I went to InRoads did resections like this, and I have seen it on a lot of data-collectors as well.

I can't help you with a basic "resection" software for a computer that does this one task only.

Sorry...just some comments. You might want to state what "platform" you're already working in.

Check the documentation of your programs for the term "trilateration" and review the web page http://www.cs.rit.edu/~ark/543/module05/trilateration.pdf for examples of solutions.

yes, Star*Net

Yup, Star*Net.

Talked to rep at MicroSurvey. Minutes later all was well and good. I couldn't have asked for a quicker or better response from them.

I had tried other programs like the aforementions TDS 48. Maybe I missed something, but I could not get around the input request for Bearings or angles.

I just hadnt thought of Star*Net until I posted here on this board.

I did DRAW IT IN AUTOCAD, but I still ended up with "guessing" where the centroid was (albeit a small guess at that). However, I haved learned over the many years that "proper procedure" can be as important as the "right answer" when the attorneys start attacking.

thanx to all,
😛
Geezer

:good:

Around 7 years ago I wrote a short program to do just that. I don't even remember what language I wrote it in now.
It was just a challenge from a former surveyor to a newbie surveyor [me] to see could I figure out the math. I was also a math major in college so that was no problem except to re-learn what I had forgotten. It took about 2 hours for me to re-learn it and solve it by hand. Then I got out my Carlson 600+ DC to compare results. I was good. Feeling spunky, I decided to write a program.
I don't remember if mine was on angles and distances. Probably was.
Seems to me it wouldn't do much good without at least one known point and some angles and distances. I would have to see the math. The law of cosines can only go so far.

> . . . Most all cogo softwares should be able to do this, and as someone said, you could do it in AutoCAD. I am sure there are softwares for programmable calculators as well that can do this. . .

Sorry but I must put my foot down; you hurt my eyes.

"Software" is an uncountable or mass noun; "softwares" is not a word. Examples of other uncountable nouns include: furniture, milk, mail.

Oops....:-$ mea culpa

Howdy,

FWIW, those interested in the ancient approach "solving it yourself," can take a look at the now obsolete Army Surveying Computer's Manual. It is n two parts and can be downloaded free at:

http://cgsc.contentdm.oclc.org/cdm/compoundobject/collection/p4013coll9/id/536/rec/8
Part 2 (sidebar at right) has the trilateration section.

Enjoy,

DMM

Since you know the co=ordinates of the stations, it should be easy to determine the distance between them. You are given the distances from your unknown to those stations. Thus you have a trivial and basic triangle problem of finding the solutions to a triangle given the lengths of the three sides.
You only need two of the distances by the way.
~Peter

> I did DRAW IT IN AUTOCAD, but I still ended up with "guessing" where the centroid was (albeit a small guess at that).

What was the distance between your CAD solution and LS package solution?