Modern surveying equipment

As late as the 1990s the basic tools used in planar surveying were a tape measure for determining shorter distances, a level for determine height or elevation differences, and a theodolite, set on a tripod, with which one can measure angles (horizontal and vertical), combined with triangulation. Since their introduction, total stations have made the technological shift from being optical-mechanical devices to being fully electronic with an onboard computer and software.

Modern top-of-the-line total stations no longer require a reflector or prism (used to return the light pulses used for distancing) to return distance measurements, are fully robotic, and can even e-mail point data to the office computer and connect to satellite positioning systems, such as a Global Positioning System (GPS). Though real-time kinematic GPS systems have increased the speed of surveying, they are still only horizontally accurate to about 20 mm and vertically accurate to about 30-40 mm. However, GPS systems do not work well in areas with dense tree cover or constructions. Total stations are still used widely, along with other types of surveying instruments.

One-person robotic-guided total stations allow surveyors to gather precise measurements without extra workers to look through and turn the telescope or record data. A faster way to measure large areas (not details, and no obstacles) is with a helicopter, equipped with a laser scanner, combined with a GPS to determine the position and elevation of the helicopter. To increase precision, beacons are placed on the ground (about 20 km apart). This method reaches precisions between 5-40 cm (depending on flight height).

2.Answer the following questions:

1. What were the basic tools in the 1990s?

2. What is a modern top-of-the-line total station?

3. How do they differ from previous instruments?

4. What are the requirements while using GPS systems?

5. Do robotic-guided total stations allow surveyors to gather more accurate measurements?

Самостійна робота № 12

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