Surveying is the process of measuring and mapping the features on the earth’s surface. It entails the calculation of distances, areas, and volumes. The purpose of surveying is to provide accurate information for the planning and construction of civil engineering projects such as roads, railways, bridges, canals, and buildings. In that case, surveying aids in assessing the suitability of an area for a particular construction project.
Surveying also assists in the management and administration of land. In this case, it is used to demarcate boundaries on land and verify ownership rights. All this, therefore, implies that a professional surveyor needs tools that can aid him/her in measurements and recording of various aspects like; distance, elevation, angles, and location among others.
Traditionally, a surveyor made use of equipment like; a tape measure and chain to measure distance, a compass to measure direction and bearings, and a dumpy level to correct for errors due to tilt. However, the field of surveying has changed dramatically in the last few decades with the introduction of modern equipment. Such equipment gives quicker more accurate results and is easier and less tedious to use compared to the traditional instruments. Some of the most common pieces of modern surveying equipment are GPS units, total stations, and drones. Each piece of equipment has its unique purpose in surveying.
Theodolite; A theodolite is an instrument that is used to measure horizontal and vertical angles. It can be used for surveying and construction. Theodolites can be either manual or electronic. Manual theodolites have a telescope that is used to measure the angles and an angular scale that is used to read the measurements. Electronic theodolites have a digital display that shows the measurements. This device is used together with a ranging rod which is often held at a distance, at the point being measured. When measuring distance, for instance, one user stands at a distance holding the ranging upright whereas the other looks through the telescope of the theodolite focussing on the ranging rod.
Automatic level; This is an upgrade from the dumpy level. It is a device with an optical compensator that maintains the line of collimation though the device is tilted. It is usually mounted on a tripod where it is calibrated into a level position using leveling screws. The device consists of a telescope which the user looks through as the other person looks and holds a graduated staff or tape measure at the place being measured. In surveying, leveling is one of the biggest causes of errors in data collection. The automatic level solves this by providing a quick and easy way to find the level.
Electronic distance measurement; An electronic distance measure, or EDM, is a device used to measure the distance between two points. They are often used in surveying and construction, and can be handheld or mounted to a vehicle. EDMs use a variety of technologies to calculate the distance, including lasers, ultrasound, and infrared. They function by emitting electromagnetic waves towards the direction of the object being measured, then computing how far the object is based on how long the reflection takes to bounce back and factoring in the speed of light. They are quick and accurate and can be used in difficult terrain where traditional measurement methods would be difficult or impossible.
GPS; Global Positioning System (GPS) technology is used to determine the location of an object or person on or near the Earth’s surface. GPS receivers use signals from a network of satellites to calculate their location. The GPS network consists of 24 satellites, and each satellite transmits signals that are received by GPS receivers on the ground. a standard GPS receiver uses a network of 4 satellites to triangulate location; 3 of the satellites are used for triangulation and the fourth is used as a reference. The receiver sends and receives signals from the satellite in real-time and based on the speed of the signals to reach the receiver and the time taken, the distance from each of the 3 satellites is computed thus pinpointing the location of the receiver.
Total station; A total station integrates the functions of a theodolite for measuring angles, an EDM for measuring distances, digital data, and a data recorder. It is essentially a modification of a theodolite, the significant difference being that, in addition to measuring angles and elevation. It is equipped with capabilities of measuring distance, data processing, data storage as well as digitally displaying data.
Drones; These are unmanned aerial vehicles equipped with sensors that are used to remotely collect data from the area being surveyed. Because it is an aerial vehicle, data can be collected in a fraction of the time compared to when it is collected manually. Combining the time-saving aspect with the fact that it is unmanned makes this a very cost-efficient method of surveying. It also comes in handy when collecting data from hard-to-reach or totally inaccessible places. For example a stip canyon or a high mountain.
Three-D scanners; These offer a cost-effective, quick, and easy method of surveying compared to the traditional equipment. It works by carrying out multiple scans from different locations at the site of interest and stores the data in form of millions of points in what is known as a 3-D point cloud. The scans are then combined to form a 3-D model of the overall scanned area. Such equipment is ideal for surveying even the most inaccessible regions of a site. They can also be used for surveying infrastructure when it comes to life cycle assessments, and risk assessments among others.
In conclusion, surveyors now have at their disposal a variety of modern equipment to aid the performance of their work. Each of these tools has its own unique set of benefits that can help surveyors in their work. Thanks to modern technology, surveyors are able to carry out their work more efficiently and accurately than ever before.