ISKRIT / Construction site / Total station adjustment
Construction site
Total station network adjustment
A raw total station file becomes an adjusted list of coordinates and heights with the accuracy of every point in under a minute.
| Point | Type | X, m | Y, m | H, m | M, mm |
|---|---|---|---|---|---|
| A | control | 6512.340 | 4120.880 | 152.314 | - |
| B | control | 6698.120 | 4255.470 | 150.982 | - |
| T1 | station | 6781.453 | 4148.231 | 149.870 | 19.8 |
| T2 | station | 6765.907 | 4009.602 | 148.527 | 27.5 |
| T3 | station | 6672.189 | 3936.039 | 147.904 | 28.7 |
It also computes what there is usually no time for: a network without control points, a traverse without extra observations, levelling without benchmarks.
In detail: features, formats, standards
The surveyor loads the total station file without editing and gets the adjusted coordinate list at once. The tool reduces both faces, merges repeated setups, proposes the fixed points from the file, removes gross blunders before the adjustment and adjusts plan and heights by least squares. Out come the coordinate list with standard deviations and error ellipses, the chi-square accuracy test, suspect observations by the tau test, traverse misclosures and an XLSX workbook.
Standards
Parametric least squares with a priori weights from the instrument standard deviations, chi-square test of the unit weight error, blunder search by the tau test on normalized residuals. Traverse tolerances follow the chosen polygonometry order or class, a theodolite traverse, or your own values. Checked against a commercial adjustment package on a published field traverse: coordinates agree within 0.6 mm in plan and 0.4 mm in height, standard deviations and error ellipses match.
Input
The raw total station file: Nikon RAW, Topcon GTS-7 and the instruments writing it, Topcon GTS-210, Sokkia SDR20 and SDR33, Leica GSI, IDEX and the System 1200 report, Carlson RW5, Trimble JobXML, Trimble DC, LandXML, Geodimeter JOB, Zeiss M5, FOIF MES, Pentax DC1 and AUX, UOMZ 6Ta3. Fixed points come from the file or are typed in, a fixed point list loads from Excel or TXT. Instrument standard deviations and the traverse class.
Output
Coordinate and height list with standard deviations and error ellipses, chi-square accuracy test, residuals and suspect observations, traverse misclosures, direct and reverse height differences, collimation and index error per round, an XLSX workbook and a TXT list.
What it does
- The raw total station file as it is: Nikon RAW, Topcon GTS-7 and the instruments writing it (GTS-6, NTS360RL, FOIF), Topcon GTS-210, Sokkia SDR20 and SDR33, Leica GSI, IDEX and the System 1200 report, Carlson RW5, Trimble JobXML, Trimble DC, LandXML with raw observations (Leica Captivate and Infinity), Geodimeter JOB, Zeiss Elta M5, FOIF MES, Pentax DC1 and AUX, UOMZ 6Ta3, the format is detected
- Both faces are reduced to one reading with collimation and vertical index error per round, a blundered reading inside a round is dropped with its line number
- Repeated setups on one point are merged, fixed points are proposed from the coordinates in the file, stations and resections are not proposed as fixed
- Least squares adjustment in plan and in height, weights from the instrument standard deviations, earth curvature and refraction
- Accuracy: unit weight error μ with the chi-square test, mx, my, M and the error ellipse of every point, the height standard deviation
- A gross blunder is removed before the adjustment by itself and the note names the file lines; a target recorded under the wrong name is found by its distance and renamed with one button
- Blunder search by the tau test on normalized residuals: a suspect observation is removed with a button and a recalculation, and restored the same way
- Traverse misclosures before the adjustment: angular, relative and in height, tolerances for 4th order, 1st and 2nd class polygonometry and theodolite traverses, or your own
- Side shots are computed with the network and get their own errors, direct and reverse height differences are checked against the tolerance, observations between fixed points show whether the list agrees with the field
- XLSX workbook: coordinate list, accuracy, plan and height residuals, traverses, height differences and rounds; the TXT list loads into the as-built drawing tool as a survey
- The measurement file is not kept on the server, calculations are stored on the server without it and reopen next time, company letterhead with signatures
Price
Free in full, no sign-up and no payment.
Open the calculator →Questions
Which files work?
The raw total station file without editing: Nikon RAW, Topcon GTS-7 and the instruments that write it (GTS-6, South NTS360RL, FOIF), Topcon GTS-210 and GTS-229, Sokkia SDR20 and SDR33, Leica GSI, IDEX and the System 1200 report, Carlson RW5, Trimble JobXML, Trimble DC, LandXML with raw observations, Geodimeter JOB, Zeiss Elta M5, R4, R5 and Rec 500, FOIF MES, Pentax DC1 and AUX, UOMZ 6Ta3. The format is detected, the encoding may be UTF-8 or Windows-1251. A TXT or CSV table in your own format is read once you say what is in which column, and a paper field book can be entered by hand or pasted from Excel.
What if there are no control points or benchmarks?
The network is still computed. Without control points the plan is adjusted freely in a local system, point errors come from the inner geometry of the network, and the list is moved into the client system by common points. Without benchmarks the levelling heights are arbitrary, from zero at the first point. A part of the network not tied to the rest is named in the notes together with what it needs.
What if there was no time for extra observations?
An open traverse, a free station on two points with one distance, an intersection without a check and a single face are computed. Points that have no checking observation are marked "no check" in the list: the adjustment will not show a blunder in them. With zero redundancy the summary says so, and point accuracy is estimated from the instrument specification.
Is the measurement file stored on the server?
No. The file is read in the browser and goes to the server only for the calculation. A saved calculation keeps the parameters, fixed points, removed observations, corrected target names and the result, but not the file itself: to recalculate, drop the file again.
How are blunders found?
In two steps. A gross blunder that shows already in the approximate coordinates, such as a distance off by several metres, is removed before the adjustment by the tool, and the note names the file lines. When a target is recorded under the wrong name, the tool finds the real point by its distance and renames it with one button. A small blunder is found after the adjustment by the tau test on normalized residuals: the suspect observation is removed with a button and a recalculation, one at a time, starting from the largest residual.
How is accuracy checked?
The unit weight error μ is compared with the chi-square bounds for the chosen probability. μ above the bounds means a blunder in the network or instrument standard deviations set too small, μ below the bounds means the observations are better than the specification. Every point gets mx, my, M and its error ellipse, heights get their standard deviation.
What were the results checked against?
Against a commercial adjustment package on a published field traverse: coordinates agree within 0.6 mm in plan and 0.4 mm in height, standard deviations and error ellipses match. The engine was also run on field files from several instruments taken from open sources.
Are header fields and signatures filled in?
Yes. The company details and signatories from the letterhead panel go into the XLSX workbook.