TRIMBLE 3300 Data Recorder
Function Name:
The data format for the Trimble 3300 data recorder is described here. Click here for details on the processing of data recorder files.
Both down load and up load functions are supported for the Trimble 3300. The Trimble file format which must be used for this interface is the REC 500 format. The other Trimble formats are not supported. The point number and point code values must also appear in the expected columns in the data file that is downloaded from the instrument, see the Communications Settings on the Instrument section below for more details. The data recorder file trimble3300.dr is supplied in the SSI_ETC: directory.
From the Survey menu, select Data recorders, then Trimble 3300 to invoke the function.
Features NOT SUPPORTED by the Trimble 3300 data recorder include:
- Temperature values are not obtained from the data recorder
- Pressure values are not obtained from the data recorder
Communications Settings on the Computer
The following parameters are set using the Data Recorders Configuration function described previously.
I/O Port : user selectable
Baud Rate : 9600
Parity : none
Data Bits : 8
Stop Bits : 1
Flow Control : hardware
Timeout : 5
Communications Settings on the Instrument
The settings described here relate to the Trimble 3305 instrument, the settings for other instruments in the Trimble 3300 range are likely to be similar.
On the instrument "Setting Interface" menu, set the following values:
0 Recording : MEM/1
1 Format : REC 500
2 Parity : none
3 Baudrate : 9600
4 Protocol : XON/XOFF
5 Position C : 11
6 Position P : 16
7 Position I : 1
8 T-O Rec. ON : NO
9 PC-DEMO : OFF
The values of "Position C", "Position P", and "Position I" are significant here in that they control the positions of the point number and point code in the downloaded data file. Surpac will only accept the values of these three variables as they are defined above. When downloading data from the data recorder to Surpac or uploading coordinates from Surpac to the data recorder you must ensure that these three variables have the correct values in the instrument.
If uploading or downloading coordinates from the instrument you must also set the instrument so that easting values are displayed before northing values. To do this, on the instrument "Setting Instr" menu, set the "4 Coord. Syst" option to be "N^->E", also set the "5 Coord. Displ." option to be "E,N".
Downloading Data from the Instrument
To download data from the instrument to Surpac you must first prepare both Surpac and the instrument.
- In Surpac's trimble 3300 function pick the option "Download to file" on the Trimble 3300 Data Recorder form. When the Begin Transfer form appears, leave the form on the screen without applying it.
- In the instrument "Data Transfer" menu select the option "1 MEM -> Periphery". You can then choose the lines you want to download. You will then be given the option to transfer the data by hitting the "yes" button, but don't do so yet.
- Now go back to Surpac and Apply the Begin Transfer form.
- Then go back to the instrument and hit the "yes" button. (NB When downloading it is important that the Begin Transfer form is applied first to ensure that all the data is captured).
Uploading Setout Points to the Instrument
To upload data from the instrument to Surpac you must first prepare both Surpac and the instrument.
- In Surpac's trimble 3300 function pick the option "Up load co-ordinates" on the Trimble 3300 Data Recorder form. When the Begin Transfer form appears, leave the form on the screen without applying it.
- In the instrument "Data Transfer" menu select the option "2 Periphery -> Mem". You will then be given the option to transfer the data by hitting the "yes" button. Hit the button now.
- Now go back to Surpac and Apply the Begin Transfer form. (NB When uploading it is important that the "yes" button on the instrument is applied before Surpac's Begin Transfer form is applied to ensure that all the data is captured).
Data Format Notes
A brief example of a Trimble 3300 data file follows:
0001 BS 18 Hz 0.0000 V1 92.1255 0002 IS 4091 Hz 0.0000 V1 92.2000 0003 INPUT th 1.80 ih 1.51 0004 INPUT th 1.80 ih 1.50 0005 2 1 e 5.88 n 6.2 h 8.3 0006 2des1 2 e 5.88 n 6.4 h 8.3 0007 2 3 SD 5.88 Hz 103.4930 V1 114.0545 0008 2des3 4 SD 9.34 Hz 85.1315 V1 105.1900 0009 2 5 SD 10.34 Hz 100.2100 V1 103.0115 0010 STN28 6 SD 13.58 Hz 102.1835 V1 98.5050 0011 2 7 SD 16.42 Hz 89.4435 V1 96.1220 0012 1 8 SD 56.87 Hz 349.1625 V1 95.4420 0013 9 SD 51.41 Hz 349.4725 V1 95.5500 0014 IS 28 Hz 0.0000 V1 92.1255 0015 1 10 SD 17.51 Hz 38.0230 V1 100.3625 0016 11 SD 5.51 Hz 46.0305 V1 128.2405 0017 12 SD 5.52 Hz 56.3620 V1 128.2300 0018 2 13 SD 5.19 Hz 86.2525 V1 127.0225 END
The Trimble-defined abbreviations are explained in the table below:
| SD | Slope distance |
| Hz | Horizontal angle |
| V1 | Vertical angle |
| th | Target height |
| ih | Instrument height |
| e | Easting of observed point |
| n | Northing of observed point |
| h | Height of observed point |
There are two important areas of point information in this example file. The area between columns 19 and 23 in this file, eg with "BS" on line 0001, and "STN28" on line 0010, stores point code information related to the entered point. The area between columns 32 and 35 in this file, eg with "18" on line 0001, and "6" on line 0010, stores point number information related to the entered point.
The point number normally stores the point number of the point, unless the line is defining an instrument station or a backsight station, in which case the value in this field is taken as the station ID. The point number is an essential piece of information. It must be present or the observation line will be ignored. Note that the point number can be found in the D2 field of the resultant string file.
The point code is used for a number of purposes:
- To define an instrument or a backsight station. If the point code is IS then this line describes the instrument station to be used for the observations. The ID of the instrument station is then taken from the point number on that line. So, for example, on line 0002 we have an instrument station with ID 4091. If the point code is BS then this line describes the backsight station to be used for the observations. The ID of the backsight station is then taken from the point number on that line, also the Hz value on this line is used as the reference angle to the backsight. So, for example, on line 0001 we have a backsight station with ID 18 and reference angle to the backsight of 0.0000.
- To identify the string number and point description if required. If it is not present then the string number for the current point is the same as the last point. If a string number is never defined then the points are assigned to string 1. Point descriptions can follow the string number in the point code. The string number is taken from the first few characters if they are numeric. The D1 field is taken from the remaining characters in the field. For example, on line 0006, the string number would be 2 and the D1 field would be "des1".
- To add a new station to the database. If the point code starts with the letters "STN" then this observation is added to the database as a new station. The ID of the station is taken to be the characters following the "STN". For example, on line 0010, a new station will be placed in the database with ID "28". This station can then be used later in the file as a new instrument or backsight station, eg line 0014. You are given some options regarding the creation of the new station. This is done via the Options for New Station form, see here for more details. Use of station errors table: If a station errors table exists in the survey database, information regarding the order of the new station may be displayed. See here for more details.
- To indicate that the observation is a Resection observation. See Resection below.
There are 5 basic line types that are supported by this interface:
- An instrument station line. Eg line 0002.
- A backsight station line. Eg line 0001.
- A heights line. Eg Line 0003.
- An observation line. Eg line 0007.
- A coordinate line (easting, northing, height). Eg line 0006.
The format of each these 5 line types must be similar to that given in the example file above. There are other line types that can be produced by the instrument, but they will be ignored by this interface.
Before an observation line can be processed an instrument station line and a backsight station line and a heights line must be entered (these three lines can be entered in any order though). A coordinate line does not need any of these other lines. If, for example, a new heights line is entered, the following observations lines will be processed with the last entered backsight and instrument stations (they don't have to be reentered). The equivalent holds if you enter a new instrument station (see eg line 0014) or backsight station line. If you make a mistake with an instrument station, backsight station, or heights line, just enter the line again - the last line is always the one that is used (see eg lines 0003 and 0004).
RESECTION
Resection is a method for determining the unknown 3D position of an occupied station by measuring angles and distances to stations whose 3D coordinates are known. Surpac allows you to enter observations to multiple known stations, and uses a least squares solver to find the best coords for the unknown station based on all the data. The least squares solver uses several parameters related to the instrument accuracy of the particular data recorder (measured angle standard deviations etc). These parameters are set using the Data Recorders Configuration function described previously.
The Trimble 3300 data recorder supports resection in Surpac.
Note on the use of Resection: Resection is a form of triangulation. Therefore for optimum results, points for observation (i.e. the resected point and the known stations to be used for the resection observations) should be selected to give strong geometric figures. That is, for the resection observations you should avoid features such as very acute turned angles between known stations, and having the new resection point and two or more of the known stations being used for the resection being in (approximately) a straight line. Another well documented limitation of the Resection method is that if you are performing a resection without recording any slope distances (i.e. you only record horizontal and vertical angles), then the resection point itself and the first three known stations used in the resection observations must not all lie on the same circle.
The implementation of resection for the Trimble 3300 data recorder is best illustrated by an example from a raw data file:
0001 BS 33 Hz 309.1831 V1 92.1255 0002 IS 50 Hz 0.0000 V1 92.2000 0003 INPUT th 0.00 ih 0.00 0004 RES33 1 SD 39.028 Hz 309.1831 V1 87.4708 0005 RES34 2 SD 16.234 Hz 351.3256 V1 88.3615 0006 RES35 3 SD 5.678 Hz 5.0136 V1 89.4230 0007 RES36 4 SD 9.650 Hz 92.3641 V1 90.1508 0008 5 SD 38.967 Hz 238.1738 V1 92.5103 0009 6 SD 10.677 Hz 195.1532 V1 87.5643
In the example above we have set up our instrument at an unknown station called 50 (which currently does not exist in the database). The nominated known backsight station is 33. We then take observations (horizontal angle, vertical angle and slope distance) to 4 known stations 33, 34, 35 and 36 (these four stations must currently be in the database). These MUST be in clockwise order and the first station MUST be the nominated backsight station. The observations are identified as resection observations using the point code. If the first three characters of the point code are 'RES' then the observations are taken as 'resection observations'. The characters after 'RES' are taken as the known station to which the observations are made. These observations are then taken to be 'resection observations'. Once an observation has been identified as a resection observation all following observations will be taken as resection observations until an observation is encountered that does not have 'RES' as the first three characters of the point code.
When the resection observations cease all the resection observations are put into a least squares solver and the coordinates of the unknown station are calculated. At this point you are given the option of putting the new resected station into the database as a permanent record, or just using the calculated coordinates temporarily. Now you can continue taking readings as though the resected station is a KNOWN instrument station, and the backsight station used is the one that you nominated for the resection observations. So in the example above, by the time we get to the first normal observation on line 0008, the station 50 is now a known station and it is used as the instrument station for this observation, and 33 is used as the backsight station. The normal observation is now surveyed as usual and its point coordinates are calculated and put in the string file. Note: You can enter a new heights line (and so change the target height) before each resection observation line.
Surpac also supports double face resection (for face left and face right observation pairs). Here the face left observation must come first (and the face left observation must have a vertical angle between 0 and 180 degrees), and the face right observation to the same station second. The readings pairs are meaned before being used in the least squares solver. Note: You cannot mix single face and double face observations in the same resection calculation. Below is an example of a double face resection:
0001 BS 33 Hz 309.1831 V1 92.1255 0002 IS 50 Hz 0.0000 V1 92.2000 0003 INPUT th 0.00 ih 0.00 0004 RES33 1 SD 39.028 Hz 309.1831 V1 87.4708 0005 RES33 1 SD 39.028 Hz 129.1831 V1 272.1252 0006 RES34 2 SD 16.234 Hz 351.3256 V1 88.3615 0007 RES34 2 SD 16.234 Hz 171.3256 V1 271.2345 0008 RES35 3 SD 5.678 Hz 5.0136 V1 89.4230 0009 RES35 3 SD 5.678 Hz 185.0136 V1 270.1730 0010 RES36 4 SD 9.650 Hz 92.3641 V1 90.1508 0011 RES36 4 SD 9.650 Hz 272.3641 V1 269.4452 0012 5 SD 38.967 Hz 238.1738 V1 92.5103 0013 6 SD 10.677 Hz 195.1532 V1 87.5643
You are given some options regarding the creation of the resected station. This is done via the Options for Resected Station form, see here for more details.
Use of station errors table: If a station errors table exists in the survey database, information regarding the order of the new resected station may be displayed. See here for more details.
Summary of important points for resection:
- The first resection observation must be to the nominated backsight station;
- The resection observations must be to stations taken in clockwise order;
- You are allowed a maximum of 20 resection observations to calculate the coords of a resection station, or 20 pairs of readings for double face observations;
- You must have horizontal angle and vertical angle readings for resection observations, but you have the option of whether to use slope distances in the calculations. For a particular resection observation line, if the slope distance is set to 0.0 in the raw data file then only the angles for that observation will be used in the least squares solver for the resection station coordinates. To achieve this for the Trimble 3300 you would have to manually edit the raw data file, to change the recorded SD value to 0.0. You can have some resection observations with and some without slope distances in the same resection calculation. For double face resection you can also have face left with a slope distance and face right without a slope distance (or vice versa). Note that slope distances are still required for all conventional point surveys.
- If angles and slope distances are present then resection observations to a minimum of two known stations are required. If only angles are present then resection observations to a minimum of three known stations are required;
- If an underground database is used and the new resected station is stored in the database, then the nominated backsight station is stored as the 'station from' and the reverse bearing from the new station to the nominated backsight station is stored as the 'reverse bearing'.
Below is an example of the report created when resections are encountered.
Jul 19, 2004
RESECTION REPORT
Purpose : Testing purpose
|
Setup information : |
|
|
Resected Station |
50 |
|
Instrument height |
0.000 |
|
Backsight station |
33 |
|
Backsight reference angle |
309.1831 |
|
Stations Used |
Y |
X |
Z |
Target Height |
|
33 |
1024.715 |
969.832 |
101.508 |
0.000 |
|
34 |
1016.053 |
997.615 |
100.395 |
0.000 |
|
35 |
1005.656 |
1000.498 |
100.027 |
0.000 |
|
36 |
999.560 |
1009.640 |
99.958 |
0.000 |
UNADJUSTED OBSERVATIONS
|
Station |
H. Angle |
V. Angle |
Slope Dist. |
|
33 |
309.1831 |
87.4708 |
39.028 |
|
34 |
351.3256 |
88.3615 |
16.234 |
|
35 |
5.0136 |
89.4230 |
5.678 |
|
36 |
92.3641 |
90.1508 |
9.650 |
INSTRUMENT ACCURACIES
|
Angle Standard Deviation (seconds) |
: |
3.000000 |
|
|
Distance standard deviation |
: |
0.002000 |
|
|
Distance ppm |
: |
2.000000 |
|
|
Instrument height standard deviation |
: |
0.003000 |
|
|
Instrument centring standard deviation |
: |
0.003000 |
|
|
Target height standard deviation |
: |
0.003000 |
|
|
Target centring standard deviation |
: |
0.003000 |
Results
|
Resected Station |
Y |
X |
Z |
|
50 |
1000.001 |
999.998 |
100.000 |
|
Standard Deviation |
0.0016 |
0.0017 |
0.0000 |
Station 50 has been inserted into the database.
OBSERVATION ADJUSTMENTS
|
Station |
H. Angle |
V. Angle |
Slope Dist. |
|
33 |
-0.0027 |
-0.0005 |
0.000 |
|
34 |
-0.0055 |
-0.0008 |
-0.003 |
|
35 |
0.0103 |
0.0032 |
-0.003 |
|
36 |
0.0020 |
-0.0031 |
-0.002 |
Note: The Observation Adjustments are tabulated above to help highlight any erroneous observations.
Note on "Standard deviations" in the RESULTS section of the RESECTION REPORT file: In general the more stations that you take readings to for the resection, the better these values become as a measure of the accuracy of the coordinates of the unknown station. This is because the more readings that exist the more "redundant" information there is. Redundant information is important in a least squares adjustment as it helps to show the consistency of the observations used to calculate the coordinates. However, even if you only take resection observations to the minimum of two fixed stations there is still some redundant information, that is one slope distance and one vertical angle, so the standard deviations are still meaningful even in this most simple case.