3.3.2. Steps involved in Total Station surveying

1. Fix the instrument on the tripod that has been firmly kept on the ground.
2. Fix the instrument on the tripod with the help of a given screw in tripod.
3. Set up the instrument on the ground point. Some instruments have optical plummet which consists of a sharp laser beam and may be used for centering purpose.

To start surveying with a Total Station, you need to securely place the instrument on a stable tripod. This ensures that it does not move during measurements, which is crucial for accuracy. First, position the tripod on a solid surface. Then, attach the instrument to the tripod using a screw to ensure that it is tightly secured. Finally, if your Total Station has an optical plummet, you can use it to center the instrument over a specific point on the ground to ensure that your measurements will be precisely aligned.

Think of it like setting a camera on a tripod for a photo shoot. Just as you want your camera to be stable to prevent blurry photos, the Total Station needs to be stable to take accurate measurements. Using an optical plummet is similar to framing your shot perfectly, making sure everything is where it needs to be before you hit 'click' or start taking measurements.

4. Levelling of the instrument approximately with the help of “bull’s eye bubble” using eye judgement. Use the standard procedure for levelling, and then correct the levelling precisely electronically.

Once the instrument is set up, you need to ensure that it is level. This is important because any tilt can lead to errors in the measurements taken. Initially, you can use the 'bull’s eye bubble' level to get an approximate level by visually checking that the bubble is centered. Then, a more precise electronic leveling process is employed to ensure accuracy. This involves adjusting the legs of the tripod or the instrument itself until it is perfectly level.

Imagine building a shelf on a wall. You wouldn't want it tilted or slanted, or things would easily fall off. Similarly, the Total Station must be level for its readings to be reliable, just like making sure your shelf is straight before putting items on it.

5. Focus the diaphragm.
6. Fix the prism on the prism rod at a known height. Since, the prism rod is graduated so height of the prism is known.
7. Measure the height of the instrument with the help of a tape.

Next, focus the instrument's diaphragm to get a clear view of the prism that will reflect signals back to the Total Station. You'll need to attach a prism to a rod, ensuring that its height is known—this is often indicated by graduations marked on the rod. You also need to measure and record the height of the Total Station itself from the ground to the instrument's eyepiece using a tape measure, as this information is critical for accurate distance calculations.

Think of it like a game where you need to aim at a target. Just as you need to know the height from which you are aiming when throwing a ball, knowing the heights of the Total Station and the prism helps ensure your aim (or measurements) is correct.

8. Set up the working unit in the instrument. Enter the height of prism pole, height of instrument, coordinates of point where instrument is kept (if known), temperature and atmospheric pressure at the site (if known).

After measuring the heights, you need to input various data into the Total Station. This includes the height of the prism pole, the height of the instrument above the ground, and if known, the coordinates of the reference point where you are placing the instrument. Additional environmental data like temperature and atmospheric pressure can also be inputted, which helps in correcting any distortions caused by weather.

This is similar to calibrating a weather station before it takes measurements. Just like how you want to ensure your weather device can give the best readings by factoring in the current weather conditions, the Total Station needs all this information to provide accurate distances and positions.

9. Focus the prism kept at the other point.
10. Bisect the centre of reflecting prism and with the help of appropriate functional buttons in the instrument. The measurement will be displayed on the display panel. Store all the measurements in the instrument itself.

Next, you will focus on the prism located at the point you want to measure to. This involves adjusting the Total Station so that you have a clear and direct view of the prism. Once aligned, use the functional buttons to bisect (or align) the center of the prism in your viewfinder. The Total Station will then calculate and display the measurements on its display panel. You can also save these measurements directly in the device for later use.

Think of this step like aiming at a dartboard. You focus on the bullseye and adjust your aim until you feel you are perfectly aligned before throwing—only in this case, your 'throw' is taking a measurement, and you can choose to save the results like keeping score.

11. Compute the other data from measured observations.
12. To speed up the work, more than one prism set is used in the field. Various persons can set up the prisms at respective locations and observer from the same location of instrument can take observations all around. It saves a lot of time in data collection.
13. Transfer the field data into desktop or laptop and process it using the related software.

After taking measurements, the Total Station computes additional necessary data from these observations. To improve efficiency, multiple people can set up prisms in different locations while the same operator collects data from the Total Station. This allows for quicker data gathering. Finally, once all field data is collected, it should be transferred to a computer, where appropriate software can be used to process the results further.

Imagine a team of chefs in a kitchen. While one chef handles the main dish, another might chop vegetables elsewhere. By dividing tasks, they speed up meal preparation. Similarly, using multiple prisms helps the team gather data faster, and transferring data to a laptop is like assembling all ingredient details to create a perfect recipe.

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