Operation (total staion)

Operation
Now that the instrument has been set up physically and electronically, you are ready for operations.
Reflector
Check to make sure that the reflector is properly mounted on the plumb pole by squeezing the small button on the lower back portion of the reflector as you slip it down over the top of the plumb pole. When you point the telescope at the reflector, the cross hairs must intersect on the yellow reflector plate as shown in Figure 1. This offset from the actual reflector is the same as the offset between the center of the telescope and the EDM.
We also have a Triple Tilt Prism Assembly that is used for longer distances .
Focusing and sighting
Focus the reticle cross hairs by pointing the telescope at some other uniformly light surface (the sky), and rotate the inner black portion of the eyepiece until the cross hairs are sharp and black.
Point telescope toward reflector by means of optical sight. Use of this sight will speed up acquisition of the reflector significantly. With both eyes open, have the image of the white cross hair in the optical sight in one eye, and the reflector in the other. When the two are superimposed, you are approximately on target. This saves a significant amount of time searching for the reflector with the actual telescope.
The horizontal and vertical rotations of the Theodolite are controlled in two ways. First you can rotate the Theodolite horizontally by hand by placing two hands on either side of it and rotating it. To rotate vertically, rotate the EDM unit up or down by hand by nudging in up or down. Manual rotation works best and is less demanding on the battery if there is a distance change from point to point of several meters. Otherwise fine-tuning is done by turning the horizontal and vertical knobs on the sides of the unit.
The instrument updates angle measurements within 0.3 seconds, so the angles can be quickly displayed. In order to see the horizontal and vertical angles of the current pointing, push F2 (DIST). Before the station is moved press F3 (REC) to record the point.
Measurement and recording

With the instrument pointed at the reflector, ensure that the reflector operator is holding the reflector still and level (by using the bubble level on the plumb pole), and then push F1 (ALL). The EDM will measure the slope distance in about 3 seconds, and it will display on the LCD of the EDM if you push (DIST). Up to this point, the data has not been recorded. To record the entire block of measured data, push (REC). If the format used is not the standard recording format (and it is not if you followed the suggestion in step 8 above), the query "OK?" appears on the display before recording the first data block. Press OK to confirm and record the first data block. This will happen each time the instrument is turned on. As you can see, with many shots, you would end up pushing often. To make things go quicker, measurements that you don't want to check can be speeded up by pushing . The instrument will measure the distance and automatically record the block of measured data and increment the current point number by 1. However, it will not display the distance or other calculated values like Easting or Northing in the LCD. To see these to check the shot, you would have to press (DATA) (SEARCH) and then to scroll through the points.
As you are surveying it may be advantageous to switch operators occasionally. Another important hint is to have simple hand signals to communicate the status of the measurement to the reflector person or the type of topography to the instrument person without having to shout or use the two-way radios for simple communications (See Communication techniques). I like to have the instrument person hold his or her arm straight up when starting to focus and measure to indicate to the reflector person that he or she should hold the reflector level. As soon as the distance measurement appears in the LCD, the instrument person's arm is held sideways to indicate that the shot is complete and the reflector person should move to the next target point. With this scheme, approximately 100 points per hour can be acquired. Our record for one day is 707 shots with three people rotating through the two positions. If the target points are further apart or in rough terrain, you may have two reflector people, and alternate shots between them. This will speed up operations, but it requires more coordination and concentration, especially on the part of the instrument person. Communication Techniques Your surveying team may not be blessed with radio communication. However, there are some basic arm signals that we have developed for geomorphic features.

	"Shoot topo points."		"I'm ready to shoot point, please level the staff."
	"End that series."
	"That was the first point for a linear feature (fault)."
	"That was the first point for a breakline."

Coding specific points and breaklines
Coding specific points or breaklines adds sort-of a dimentional character to your map. We generally use the Total Station to produce maps or profiles that contain features-such as topographical breaks in slope-that, when accentuated with a polyline, provide a three dimentional view on the map. This section will discuss the coding system and cover the keypad procedure.
There are basically three types of codes: specific survey point codes (i.e., landmarks), polyline codes (i.e., topographic breaks), and physical feature codes (i.e., flotsam, trees). Specific survey points, such as a benchmark or survey mark are denoted by a symbol other than a dot. Polylines connect a given set of points to denote a ridge, stream, scarp, etc., and provide a line of which topolines will "break" along when plotted using the Liscad software. Also, physical features such as vegetation, roads, buildings, and electric can be symbolized on a map.
To assign a point or set of points to a code, first shoot the point as described in Table 4, only make sure to press F2 DIST. Next, you must set that point to a code number.
See this link for coding details: coding. Data downloading, manipulation, and software
I want to emphasize again the importance of taking good notes while surveying. A few quick annotations may save a major hassle down the road. Use the Survey Record Form to organize the observations, and your organization and manipulation of the data should go smoothly.
Data storage format The memory card stores two types of information units: measurement blocks and code blocks. With our present software set up, we don't use code blocks. You are welcome to experiment with them. Other more sophisticated software systems use the code blocks as part of the data organization. The measurement blocks contain measured data and a point number. Each block includes a consecutive unique block number which is recorded automatically. If possible, record both the point number and block number on the Survey Record Form in order to avoid ambiguity later.
The memory card data is made up of data blocks, each of which is made up of words with a fixed length of 16 characters per word. Each block may contain up to 8 words. A measurement block has the following data format:

Word 1	Word 2		Word n
Point number		....		End character

The first word of a measurement block always contains the point number. The remaining words of the block are determined by the measurement format of the Theodolite. Here is an actual data block:
110001+00000000 21.103+09803900 22.103+08849970 31..00+00258533 51....+0100+000 81..00+00255904 82..00-00036142 83..00+00007194
While it appears quite cryptic, you can see the word identifiers in there at the beginning of each word indicating the data (31 for example is slope length). The first word, 110001+00000000, contains the word identifier, 11, meaning point number (click here for more codes; 21 is the horizontal angle, 22 is the vertical angle (measured from zenith, so that is why it is usually around 90 for the typical nearly horizontal shot0, 31 is the slope length, and 81, 82, and 83 are the easting, northing, and elevation respectively), then it is followed by the block number (0001), and then the point number (00000000). Each of these will be incremented automatically. The running point number may be changed or input as surveying proceeds, but the block numbers are unique. See coding for corresponding features.
Downloading The data should be downloaded from the SRAM card when the surveying is complete. The SRAM card should then be cleared of data for the next surveying trip. The Macintosh computer systems that we use are not the type supported by the surveying community; therefore, our scheme is original and somewhat circuitous, but effective. In the motel, truck, or office, remove the SRAM card from the Total Station, and insert it in the laptop. Open Microsoft Excel and open file. Excel will ask you to choose from several options: plate 1- select delimited; plate 2- select space and tap delimiters; plate 3- finish. All your data will be in the form indicated below in the raw data block. This form needs to be changed to either be viewed by Liscad or as northing, easting, and elevation in excel.

Note that these days (2004), I typically just parse the raw file in excel and put a column break in on the left side of each plus as well as at the spaces, and then you can delete the columns you don't want and will have millimeters for the unit for the distances and easting, norrthing, and elevation which you can easily correct.
Filtering the data
Obviously the raw data is of little use for analysis.


Raw data block:
110549+00006000 21.323+07291800 22.323+09123700 31..00+00180854 81..10+01172836 82..10+01053110 83..10+00996292 87..10+00001300 410550+00000005 42....+00001101

Block #	Point #	Easting E	Northing N	Elevation H	Horiz. angle Hz	Vertical angle V	Slope length D
549	6000	117.2836	105.3110	99.6292	72.91800	91.23700	180.854

To view as easting, northing, and elevation data in excel, you must first delete rows that are not needed. The word identifiers (the first two numbers at the beginning of the word) indicate the code of the word. We keep the point number, 41 (point number), 42 (code), 81 (easting), 82 (northing), and 83 (elevation). Delete all other columns. Be careful not to delete columns where additional data was recorded causing a shift of words. You also need to add this to the header (first line):

Wild REC-TotalStation

Here is a sample that works. It is important to note that the data should be in this order because the program (liscad) will take the second three words and assume that they are Easting, Northing, and Elevation.

Wild REC-TotalStation
110549+00006000 81..10+01172836 82..10+01053110 83..10+00996292
410550+00000005 42....+00001101
110551+00006001 81..10+01177605 82..10+01046419 83..10+00992448
110552+00006002 81..10+01185919 82..10+01040090 83..10+00986772
110553+00006003 81..10+01193146 82..10+01036721 83..10+00985793
110554+00006004 81..10+01196477 82..10+01035305 83..10+00985896
110555+00006005 81..10+01211466 82..10+01026636 83..10+00979522
110556+00006006 81..10+01215893 82..10+01023119 83..10+00978902
110557+00006007 81..10+01221285 82..10+01019707 83..10+00977450
110558+00006008 81..10+01225470 82..10+01015623 83..10+00976024
110559+00006009 81..10+01240939 82..10+01016348 83..10+00975100
110560+00006010 81..10+01253217 82..10+01013742 83..10+00971985
110561+00006011 81..10+01271393 82..10+01012739 83..10+00969438
110562+00006012 81..10+01286564 82..10+01008193 83..10+00966146
110563+00006013 81..10+01290373 82..10+00997422 83..10+00964371
410564+00000005 42....+00000000
110565+00006014 81..10+01296148 82..10+00970876 83..10+00961116
110566+00006015 81..10+01302319 82..10+00944821 83..10+00958195
110567+00006016 81..10+01278370 82..10+00934876 83..10+00957227
110568+00006017 81..10+01272799 82..10+00954352 83..10+00959228
110569+00006018 81..10+01261752 82..10+00980963 83..10+00962315
110570+00006019 81..10+01265783 82..10+01001572 83..10+00965681
410571+00000005 42....+00002101
110572+00006020 81..10+01265783 82..10+01001563 83..10+00965681
110573+00006021 81..10+01253140 82..10+01001680 83..10+00966532
110574+00006022 81..10+01238534 82..10+00999553 83..10+00966963
| 110575+00006023 81..10+01250007 82..10+00944827 83..10+00957900

Lastly, save excel worksheet with a .ex extension. This file will be the master archive for your data. From it you can manipulate, plot, and contour your data. Print this file out and save the hardcopy somewhere safe.
Care
Our surveying equipment is fairly rugged and designed to last. However, it is also expensive and likes a little attention and Tender Loving Care occasionally. Giving the equipment a good cleaning occasionally and treating it with care will ensure that it will last for a long time. Here are some basic suggestions.
Transport
For transport, use shockproof packaging material for the instruments. We have nice carrying cases for the EDM and Total Station and most of the associated hardware. While these cases add significant weight, they really do protect the instruments, and the one time that you decide to lighten your load and only carry the instruments, will be the one time that they fall down a hill and are severely damaged--a fall which they would have survived had they been in the cases!
Cleaning and drying
Before cleaning, blow dust off lenses and prisms. Handle lenses, eyepieces and prisms with special care. Always use a soft, clean cloth or clean cottonwool. Breathe on glass components, then wipe gently. If necessary, slightly moisten cloth or cottonwool with pure alcohol. Do not use any other liquid. Never touch optical glass with your fingers.
Cables and plugs
Clean periodically. Do not let plugs get dirty. Protect from moisture. Use pure alcohol to rinse dirty cable connectors, then leave to dry thoroughly.
Condensation on prisms
When a prism is cooler than the ambient air it may collect condensation. If this happens, warm the prism for some time by placing it in a warm environment (room, vehicle, or inside clothing). Merely wiping the prism is useless.
Storage
If an instrument has become wet, unpack it on return to base. Carefully clean the instrument, accessories, case and foam inserts. Wipe dry. Repack only after all the equipment is again thoroughly dry.
In the field
The main perils in the field to the instrument are rain, blowing sand, heat, and being knocked over. If it is raining or blowing hard, you will have to postpone the effort. Protect against light mist and moderately blowing sand by placing one of the plastic hoods (stored in the EDM case) over the instrument whenever it will not be used for longer than several minutes. If the temperature is less than -20°C or greater than +50 °C, you should not operate the instrument. Protect against temperature fluctuation with an umbrella. Walk carefully when working around the instrument and when setting up, check to make sure that the area is clear of debris that may be an obstacle.
How it works