GEODAT 400 and GEODAT 600

You can use these functions to download data from, and upload data to, the Geodat 400 and 600 data recorders. The data recorder files geodat400.dr and geodat600.dr are supplied in the SSI_ETC: directory.

To run this function: Choose Survey > Data recorders > Geodat 400, or Survey > Data recorders > Geodat 600, or...

In the Function Chooser, type GEODAT 400, and press ENTER.
In the Function Chooser, type GEODAT 600, and press ENTER.

GEODAT 400 and 600 Output

Output with one record per line in the raw data file, see below.

50=3
2=91         < (1)
3=1.52       < (1)
62=92        < (2)
21=0         < (2)
5=1
6=0
9=13.76
8=94.033
7=.0006
4=12DESCRIPT
6=1.5
5=2
6=4.18
8=92.1152
7=48.3014
-9,

Note: The order of the blocks of data shown by (1) and (2) are unimportant but they must precede any observed point data.

The following applies to both the GEODAT 400 data logger and earlier GEODAT126 data recorder.

If a surveyed point is to be used as a new station then use the following code system:

4=STNABC If the first three characters of the '4=' field are 'STN', then the point is a new control station. When Surpac calculates the coordinates of the new station it gives the station the name you entered after 'STN', that is 'ABC' in the above example.

If you are surveying a new station underground and want to store the height from the floor to the target, you must enter the height in millimetres separated by a comma immediately after the station identifier. For example,

4 = STNABC, 2357In this example, the height from the floor to the target at station `ABC' is 2.357.

You are given some options regarding the creation of the new station. This is done via the Options for New Station form, which appears once the new station coords have been calculated:

Options for new Station form

Station

This is just an informational field that displays the name of the new station being created.

Insert station into database?

Do you want to put this new station into the database, or just store the station coordinates temporarily?
Just storing the new station temporarily allows you to use the new station as the next instrument station. This feature should help to prevent your database from becoming clogged up with temporary stations.

Note: If you choose not to put the new station in the database then the following hold:

You can only use the new station as the very next instrument station defined in the current job (eg if you call the new station TP1, then you can use TP1 as the very next instrument station, but if the next instrument station in the job is not TP1, then you cannot go back to using TP1 after this).
The new station coordinates can only be used in the current job, i.e. you cannot use them in the next job.
If more than one new station is created and not put into the database in the current set up, then only the last of these can be used as the next instrument station (Eg say, in a particular set up, you create new stations TP5, then TP6, then TP7 and elect not to put any of them into the database. Only TP7, being the last one created, can be used as the next instrument station in the next set up).

Store as surface or underground station?

Do you want to store the new station as a surface or underground station? Surveying in underground mines presents some unique problems caused by the frequent occurrence of very short lines of sight. The bearings which are subsequently calculated using the known station coordinates on these very short lines are likely to deviate significantly from the bearings obtained by successively adding the horizontal angles to the bearing from the setup station to the backsight station. To resolve this problem, underground type stations use a field `rev_brng' in which the carried bearing is stored. Any survey function which accepts input of survey observations to calculate the coordinates of new points will use this stored bearing, if appropriate, to calculate the coordinates of the new points. For underground type stations, connections between stations are defined by the contents of the `station_fr' field for each station in the database. If you store the station as surface type then bearings are ALWAYS calculated using the known station coords.

Instrument used

Enter the instrument (as defined in the station errors table) used for the calculations. An example value is LEICA1101. For explanatory information on the station errors table see here. This pick-list will be populated with the instruments from the station errors table. This field will only be selectable if ALL of the following hold:

A station errors table exists in the survey database
Multiple instruments have been defined in the station errors table (ie there is a choice of instruments)
The new station has NOT been created using just one horizontal angle, one vertical angle and one slope distance observation

Press Apply on this form to continue processing this station, or Cancel to cancel processing of this station.

Note: These options are new features post Surpac V5.0. As it involves displaying a new form, it may have the effect of disrupting some macros from earlier versions of Surpac. To fix these macros look in the macro text for the occurrence of frm00263 (the New Survey form) followed by frm10073 (the Interactive Database Modification form), and between these two forms insert the following:

frm00849=table { _action } {
    { "apply" }
    { "apply" }
    { "apply" }
    { "apply" }
  }

Use of the station errors table for creation of a new station from single horizontal angle, vertical angle and slope distance readings:

The station errors table is an optional table in the survey database that allows a quality assurance regime to be set up for new stations entering the survey database. For explanatory information on the station errors table see here. Rules for the case where a new station is created with a single horizontal angle measurement, a single vertical angle measurement and a single slope distance measurement are defined in the station errors table. These rules can lead to the display of information/warning/error messages when a new station is created with data of this type. The messages can be:

No message. The calculation process continues with no message being output.
INFORMATIONAL. A form is displayed with information on how the new station order was calculated. Press OK on this form to continue (the new station will) be created).
WARNING. A form is displayed with information on how the new station order was calculated. You have a choice of whether or not to create the new station. Select OK on the form to create the new station, or CANCEL to not create the new station.
ERROR. A form is displayed with information on how the new station order was calculated. Press OK on this form to continue (the new station will) be created).

Station

The name of the new station being created.

Case

Informational text to identify that the station is being created from a single horizontal angle measurement, a single vertical angle measurement and a single slope distance measurement.

Preliminary order from station errors table

The station order from the station errors table for stations created from a single horizontal angle measurement, a single vertical angle measurement and a single slope distance measurement.

Backsight station

The name of the backsight station.

Backsight station order

The order of the backsight station.

Setup station

The name of the setup station.

Setup station order

The order of the setup station.

Final new station order

The final new station order is chosen as the lowest ranking (the ranking of the orders is defined inside the station errors table) of the three orders:

Preliminary order from station errors table
Backsight station order
Setup station order

You have a choice of whether or not to create the new station. Select OK on the form to create the new station, or CANCEL to not create the new station.

Multiple Face Observations To New Stations

The GEODAT 400 data recorder supports multiple face pointings to a new foresight station. This is when a number of angles and distances to a backsight and foresight station are read and the mean value is used to determine the coordinates of the new station. Before multiple face pointings can be used, the backsight and setup station details must be identified and the instrument and target heights must also be defined. To indicate that Multiple Face Observations have commenced the value "STARTMFO" must be recorded in the point code of the first observation to the backsight station. The station ID must be immediately after "STARTMFO". Thus, "STARTMFOXYZ" indicates the Multi-Face Observations to a new station XYZ have commenced. To indicate that multi-face observations to the new station have been completed the last observation to the new station must have "ENDMFO" in the point code field.

4 = STARTMFOXYZ, 2357

In this example, the height from the floor to the target at station `STARTMFOXYZ' is 2.357.

Between and including the first and last observations mentioned above, the observations must be present in pairs with the order being

Backsight observation Foresight observation Backsight observation Foresight observation Backsight observation Foresight observation etc.

As many observations as required may be measured and recorded. The angles and distances are meaned and the means are used to calculate the coordinates of the new station.

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.

Below is an example of a multi-face observation with the corresponding .not file which is created to provide details of the calculation.

5=3 
6=1.5 
9=9.4
8=90.5522 
7=44.3246 
4=STARTMFOXYZ
5=4 
6=1.5 
9=13.56 
8=93.0512 
7=224.3246 
4=1 
5=5 
6=1.5 
9=21.12 
8=92.0412 
7=55.36 
4=1 
5=6 
6=1.5 
9=13.57 
8=93.0510 
7=235.3610 
4=ENDMFO

		TOTAL STATION TRAVERSE REPORT

Purpose : Testing purpose
Station		N	E	Z
Backsight 92		200	200	100
Instrument 91		100	100	100
Foresight XYZ

Instrument height	:		1520
Target height	:		1500

OBSERVATIONS
Backsight	Foresight	H. angle		V. angle	Slope angle	Slope dist
44.3246	224.3246	180.000		93.0512	-3.0512	13.560
55.3600	235.3610	180.0010		93.0510	-3.0510	13.570

Mean		180.0005			-3.0511	13.565

New Station
Station							N	E	Z
Foresight XYZ							90.422	90.422	99.290

Bearing to				XYZ			:	225.0005
Distance to				XYZ			:	13.545

Use of the station errors table for creation of a new station from multiple horizontal angle, vertical angle and slope distance readings:

The station errors table is an optional table in the survey database that allows a quality assurance regime to be set up for new stations entering the survey database. For explanatory information on the station errors table see here. Rules for the case where a new station is created from multiple horizontal angle, vertical angle and slope distance measurements are defined in the station errors table. These rules can lead to the display of information/warning/error messages when a new station is created with data of this type. The messages can be:

No message. The calculation process continues with no message being output.
INFORMATIONAL. A form is displayed with information on how the new station order was calculated. Press OK on this form to continue (the new station will) be created).
WARNING. A form is displayed with information on how the new station order was calculated. You have a choice of whether or not to create the new station. Select OK on the form to create the new station, or CANCEL to not create the new station.
ERROR. A form is displayed with information on how the new station order was calculated. Press OK on this form to continue (the new station will) be created).

Below is an example of an INFORMATIONAL form:

Station

The name of the new station being created.

Case

Informational text to identify that the station is being created from multiple horizontal angle, vertical angle and slope distance measurements.

Instrument

The instrument value from the station errors table that was chosen for this survey. If this field is null, then the station errors table does not contain multiple instruments.

parameter

The standard deviation parameter under consideration.

num meas

The number of measurements taken for the particular parameter value.

value

The value of the standard deviation for the particular parameter. If the parameter is HORIZONTAL ANGLE STANDARD DEVIATION or VERTICAL ANGLE STANDARD DEVIATION the units of this value will depend on the angle units you have chosen for Surpac. If you have selected DEGREES as your angle units, the value will be in seconds (eg 1.0, 5.0, 50.0, 120.0 etc); if you have selected GRADS as your angle units, the value will be in GRADS. If the parameter is SLOPE DISTANCE STANDARD DEVIATION then the value will be in the distance units.

dist

If the parameter is HORIZONTAL ANGLE STANDARD DEVIATION this distance is the horizontal distance from the setup station to the new (ie the foresight) station. If the parameter is VERTICAL ANGLE STANDARD DEVIATION this distance is the slope distance from the setup station to the new (ie the foresight) station. If the parameter is SLOPE DISTANCE STANDARD DEVIATION, then this field is not used and will be null.

order

This is the order value as determined from the station errors table for this Instrument, parameter, num meas, value and dist combination.

Preliminary order from station errors table

This order is the lowest ranking (the ranking of the orders is defined inside the station errors table) order of the orders given in the "Orders from station errors table" box above.

Backsight station

The name of the backsight station.

Backsight station order

The order of the backsight station.

Setup station

The name of the setup station.

Setup station order

The order of the setup station.

Final new station order

The final new station order is chosen as the lowest ranking (the ranking of the orders is defined inside the station errors table) of the orders:

Preliminary order from station errors table
Backsight station order
Setup station order

Select OK on the form to continue and create the new station

Drill Hole Surveys By Extended Rod Method

The GEODAT 400 data collector supports drill hole surveys using the EXTENDED ROD METHOD. This method requires that observations are made to two points on a rod which protrudes from a drill hole. The first observed point MUST be closest to the hole collar. The drill hole ID, the distance of the first point from the collar (along the rod), the distance between the two surveyed points (along the rod) and the dip of the rod (measured by clinometer) must be stored in the point code of the first observed point.

The dip of the rod and the distance between the two points are included as check measurements and have no effect on the results of the calculations. The distance from the first point to the hole collar is essential as it is used to determine the collar position in the case when the first point is not exactly at the collar.

Below is an example of an observation on a drill hole using this method. Typically a target height of ZERO should be used as the measurements are generally taken to the rod.

5=2
6=0.0
9=10.908
8=91.2202
7=101.5757
4=STARTDHSABCD,2.02,1.4,-60
5=3
6=0.0
9=11.529
8=85.1439 
7=103.5756 
4=1 
4=STARTDHSABCD,2.02,1.4,-60

The point code "4=" of the first point is described below:

4=STARTDHSABCD,2.02,1.4,-60

The text "STARTDHS" signifies the start of a drill hole survey.
The drill hole ID is "ABCD".
The collar extension distance is 2.020
The Distance between the 2 points on the rod protruding from the collar is 1.4
The hole dip measured by clinometer is -60.

Below is an example of the report produced from the above survey. This report in a `.htm' file format. You can select the format of the report file (for example htm, rtf, not, csv).

	DRILL HOLE COLLAR SURVEY

Purpose: Testing purpose

Hole Id	:	ABCD
N	:	7402.035
E	:	2631.466
Z	:	3480.731
Bearing	:	143.2017
Dip by clinometer	:	-60.00	by observation :	-59.58
Collar extension	:	2.02
End to collar by tape	:	1.400	by observation :	1.405

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 GEODAT 400 and GEODAT 600 data recorders support 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 GEODAT 400 and GEODAT 600 data recorders is best illustrated by an example from a raw data file:

50=PC29038
2=NEWSTATION
3=0.0
62=STN1
21=309.1831
5=1
9=39.028
8=87.4708
7=309.1831
6=0.0
4=RESSTN1
5=2
9=16.234
8=88.3615
7=351.3256
6=0.0
4=RESSTN2
5=3
9=5.678
8=89.4230
7=5.0136
6=0.0
4=RESSTN3
5=4
9=9.650
8=90.1508
7=92.3641
6=0.0
4=RESSTN4
5=1001
9=38.967
8=92.5103
7=238.1738
6=0.0
4=1

In the example above we have set up our instrument at an unknown station called NEWSTATION (which currently does not exist in the database). The nominated known backsight station is STN1. We then take observations (horizontal angle, vertical angle and slope distance) to 4 known stations STN1, STN2, STN3 and STN4 (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 by the coding system:

4=RESABC

If the first three characters of the '4=' field 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 a '4=RES' 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 point 1001, the station NEWSTATION is now a known station and it is used as the instrument station for point 1001, and STN1 is used as the backsight station. Point 1001 is now surveyed as a normal point and its coordinates are calculated and put in the string file.

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:

50=PC29038
2=NEWSTATION
3=0.0
62=STN1
21=309.1831
5=1
9=39.028
8=87.4708
7=309.1831
6=0.0
4=RESSTN1
5=2
9=39.028
8=272.1252
7=129.1831
6=0.0
4=RESSTN1
5=3
9=16.234
8=88.3615
7=351.3256
6=0.0
4=RESSTN2
5=4
9=16.234
8=271.2345
7=171.3256
6=0.0
4=RESSTN2
5=5
9=5.678
8=89.4230
7=5.0136
6=0.0
4=RESSTN3
5=6
9=5.678
8=270.1730
7=185.0136
6=0.0
4=RESSTN3
5=1001
9=38.967
8=92.5103
7=238.1738
6=0.0
4=1

You are given some options regarding the creation of the resected station. This is done via the Options for Resected Station form, which appears once the new station coords have been calculated:

Options for Resected Station form

Station

This is just an informational field that displays the name of the new station being created.

Insert station into database?

See here for an explanation of this field.

Store as surface or underground station?

See here for an explanation of this field.

Instrument used

Enter the instrument (as defined in the station errors table) used for the calculations. For explanatory information on the station errors table see here. This pick-list will be populated with the instruments from the station errors table. This field will only be selectable if BOTH of the following hold:

A station errors table exists in the survey database
Multiple instruments have been defined in the station errors table (ie there is a choice of instruments)

Press Apply on this form to continue processing this station, or Cancel to cancel processing of this station.

Use of the station errors table for creation of a new station from a resection:

The station errors table is an optional table in the survey database that allows a quality assurance regime to be set up for new stations entering the survey database. For explanatory information on the station errors table see here. Rules for the case where a new station is created from a resection are defined in the station errors table. These rules can lead to the display of information/warning/error messages when a new station is created with data of this type. The messages can be:

No message. The calculation process continues with no message being output.
INFORMATIONAL. A form is displayed with information on how the new station order was calculated. Press OK on this form to continue (the new station will) be created).
WARNING. A form is displayed with information on how the new station order was calculated. You have a choice of whether or not to create the new station. Select OK on the form to create the new station, or CANCEL to not create the new station.
ERROR. A form is displayed with information on how the new station order was calculated. Press OK on this form to continue (the new station will) be created).

Station

The name of the new station being created.

Case

Informational text to identify that the station is being created from a resection.

Instrument

The instrument value from the station errors table that was chosen for this survey. If this field is null, then the station errors table does not contain multiple instruments.

The following 5 field descriptions relate to fields inside the "Orders from station errors table" box:

parameter

The standard deviation parameter under consideration.

num meas

The number of measurements taken for the particular parameter value. Note: For the purposes of the station errors table a single face or a double face resection observation both just count as one observation (ie double face resections do not count double).

value

The value of the standard deviation for the particular parameter.

dist

For a resection, this field is not used and will be null.

order

This is the order value as determined from the station errors table for this Instrument, parameter, num meas and value combination.

Preliminary order from station errors table

This order is the lowest ranking (the ranking of the orders is defined inside the station errors table) order of the orders given in the "Orders from station errors table" box above.

The following 2 field descriptions relate to fields inside the "Orders for fixed stations" box:

station

The name one of the fixed stations involved in the resection (the fixed stations being the backsight station and the stations to which resection observations are made).

order

The order of that fixed station (from the survey database).

Final new station order

The final new station order is chosen as the lowest ranking (the ranking of the orders is defined inside the station errors table) of the orders:

Preliminary order from station errors table
All the orders of the fixed stations

You have a choice of whether or not to create the new station. Select OK on the form to create the new station, or CANCEL to not create the new station.

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 the slope distances are optional. If the slope distances do not appear or are set to 0.0 in the raw data file then only the angles will be used in the least squares solver for the resection station coordinates. 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.

RESECTION REPORT

Purpose : Testing purpose

Setup information :
Resected Station	NEWSTATION
Instrument height	0.000
Backsight station	STN1
Backsight reference angle	309.1831

Stations Used	Y	X	Z	Target Height
STN1	1024.715	969.832	101.508	0.000
STN2	1016.053	997.615	100.395	0.000
STN3	1005.656	1000.498	100.027	0.000
STN4	999.560	1009.640	99.958	0.000

UNADJUSTED OBSERVATIONS

Station	H. Angle	V. Angle	Slope Dist.
STN1	309.1831	87.4708	39.028
STN2	351.3256	88.3615	16.234
STN3	5.0136	89.4230	5.678
STN4	92.3641	90.1508	9.650

INSTRUMENT ACCURACIES

Angle Standard Deviation (seconds)	:	3.000000
Distance standard deviation	:	0.005000
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
NEWSTATION	1000.003	1000.002	999.999

Standard Deviation	0.0016	0.0017	0.0000

Station NEWSTATION has been inserted into the database.

OBSERVATION ADJUSTMENTS

Station	H. Angle	V. Angle	Slope Dist.
STN1	-0.0027	-0.0005	0.000
STN2	-0.0055	-0.0008	-0.003
STN3	0.0103	0.0032	-0.003
STN4	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.