3.1. Introduction

Long distance measurements on the ground by conventional method has always been a problem in surveying.

In traditional surveying, measuring long distances can be quite challenging because it often requires physical tapes or rods, which can be cumbersome and difficult to manage over large areas. This process can be slow, and errors can easily occur due to human judgment or environmental factors.

Imagine trying to measure the length of a football field using a measuring tape; it would require precision, and if the tape shifts or sags, it could lead to inaccurate results. Now, consider trying to do that across a large park – it would be tedious and prone to mistakes.

The use of electronics in modern surveying equipment has ease the process. Electronic Distance Measuring (EDM) device can be used for measuring the long distances (slope distances) with higher accuracy, thus saving a lot of time (Garg, 2021).

The introduction of Electronic Distance Measurement devices revolutionized surveying by utilizing electronic technology to improve accuracy and speed. EDMs operate by sending out electronic signals, which bounce off targets and return to the device, allowing for precise measurements without the need for physical contact over long distances.

Think of EDMs like a game of ping pong: you hit the ball (the signal), and the speed and time it takes for the ball to bounce back to you helps calculate the distance. This is much quicker and more accurate than counting steps on a long walk to measure a distance.

Early EDM instruments were large, bulky, complicated and expensive, but the improvements in electronics over a period of time have made them lighter, portable, simpler, and affordable.

Initially, EDM devices were not user-friendly. They were heavy and required extensive training to operate. However, advancements in technology have led to significant improvements in their design, making them more accessible for everyday use by surveyors. Modern EDMs are now lightweight and easy to transport, encouraging more professionals to adopt them in their practice.

Think about how smartphones have evolved from bulky, complicated devices to sleek, user-friendly gadgets that fit in your pocket. Similarly, EDMs have become more user-friendly, allowing surveyors to focus more on the task than on operating complicated machines.

These EDMs can be mounted on tribrach or standard units or theodolites, and can be used with theodolites (both digital and optical) or as an independent unit (Subramanian, 2012).

Modern EDM devices can be integrated with other surveying instruments, such as theodolites—an instrument used for measuring angles in the horizontal and vertical planes. This integration allows surveyors to take angle and distance measurements simultaneously, enhancing overall efficiency and accuracy in fieldwork.

Think of it like using a smartphone that combines a camera and GPS navigation. Instead of carrying multiple devices, you have everything in one, simplifying your tasks and making them more efficient.

Total Station equipment, which is a combination of digital theodolite, an EDM and a small processor to process the data, can be used for taking multiple observations in the field, and thus this equipment eliminates the need of taking several surveying equipment in the field.

Total Stations are a significant advancement in surveying technology as they combine several functions into a single device. They integrate angle measurements, distance measurements, and data processing capabilities, which means surveyors can carry just one device that efficiently collects all necessary data.

Imagine a Swiss army knife that includes various tools such as a knife, screwdriver, and scissors, all in one device. Instead of carrying multiple tools, you have the convenience of one tool doing multiple jobs, just like how a Total Station streamlines surveying tasks.

The Global Positioning System (GPS) traditionally refers to the North American global positioning system, or satellite positioning system. Originally known as Navigation Satellite Timing and Ranging (NAVSTAR), GPS was developed by the US Department of Defense for military use in the 1970s.

GNSS, which includes systems like GPS, encompasses a variety of satellite systems designed to provide accurate positioning information anywhere on Earth. By using signals from multiple satellites, GNSS receivers can precisely determine their own locations in three-dimensional space, which is essential for modern surveying.

Consider how your smartphone uses GPS to pinpoint your location. Just as it helps you find directions in real-time, GNSS in surveying helps professionals obtain accurate geographic data instantly, enhancing planning and development.

The availability of EDM, Total Station and GNSS has eased the data collection and mapping work, and considerable reduced the cost and time to complete the survey work, as compared to conventional surveying equipment (Gopi et. al., 2017).

The integration of modern surveying technologies such as EDMs, Total Stations, and GNSS has transformed the field of surveying. These devices significantly cut down the amount of time and labor required to gather data, making the overall process much more efficient than traditional methods, which often included more manual measurements and calculations.

Think about how using a calculator speeds up math homework compared to doing it by hand. Just as a calculator helps streamline problem-solving, modern surveying instruments help surveyors complete their work more quickly and accurately.

However, today Total Station equipment, which has an in-built EDM, can be used to measure the long distances. So, now-a-days, there is no need to buy the EDM system separately.

Modern Total Stations often come equipped with built-in EDM capabilities, meaning that surveyors do not need to invest in separate EDM devices. This integration not only reduces costs but also enhances efficiency, as it allows for seamless measurements of both distances and angles using one tool.

Think of it like buying a multifunction printer that can print, scan, and copy all in one. Instead of buying three separate devices, you get convenience and functionality in one package.

Looking at the potential use of both (Total Station and GNSS), a combination of both has emerged in the market, called a Smart Station.

Smart Stations are the latest advancement, designed to combine the functions of Total Stations and GNSS receivers into one device. This technology is particularly useful in the field as it allows surveyors to conduct various types of measurements without needing multiple instruments, streamlining their workflow.

Similar to how a smartwatch combines the functionality of a watch, fitness tracker, and smartphone notifications, a Smart Station integrates the capabilities of Total Stations and GNSS for enhanced surveying efficiency.

This module will cover the details and working of EDMs, Total Station and GNSS.

The upcoming parts of the module will delve deeper into how each of these technologies functions, their components, how to operate them effectively, and the applications they are used for in surveying. Understanding these concepts is crucial for students and professionals to stay current with industry standards.

Just like in a cooking class where each section might cover different techniques or ingredients, this module is structured to educate on the individual pieces of technology and how they fit into the broader context of modern surveying.

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