Many kinds of surveying equipment have been used in the past and present to help a surveyor measure various parameters of a land area. Each of these parameters is measured by a specific type of measuring equipment. In this article we will learn about the importance of the main types of surveying equipments, both old and new.
Surveying Equipments – Old
In ancient times surveying equipment included chains, compass, solar compass, transit, theodolite and more. Chains with equal size links were used to measure distance between two required points. A compass was used to measure the direction of a line that was being surveyed. A solar compass was used for measuring both the direction and latitude of a particular point with the help of sun and stars. A Solar Compass could also measure horizontal angles and the “true north" of a particular place. A metallic measuring tape was used to measure shorter distances.
As technology gradually advanced with time, instruments used for surveying also improved. Horizontal and vertical angles were measured using a simple theodolite whereas different heights were measured by a basic level. Measuring wheels were also initially used by surveyors to measure long distances in a short duration of time. Measuring wheels came in two types: mechanical and electrical, and both worked on the same principle of rolling the wheel from the start to the end point.
In the early 1900s, surveyors started to use surveying equipment such as planimeters, theodolites, automatic levels and measuring wheels. A planimeter is the best known tool for measuring asymmetrical land areas as they eliminate the need for charts or manual calculations; whereas a theodolite allows measuring of horizontal and vertical angles. A theodolite consists of a movable telescope attached over perpendicular axis. It provides precise measurement of angles and is an integral part of every surveying tool kit. A transit is a type of theodolite but has less precision.
An auto level or a dumpy level is also a type of surveying equipment used for measuring horizontal levels. It consists of a telescope like device fitted on a tripod stand. Auto level, tilting level, and self-leveling level are all types of leveling instruments, each providing different rotating capabilities.
Most surveying instruments are fixed on a tripod, which acts as a support. As the name suggests, tripods have three legs with length varying capability. Many of these equipments are still used by surveyors around the world.
Surveying Equipments – New
Recent development in technology has provided some of the finest surveying equipments present today. Moreover, with the introduction of global positioning system, the methods of surveying have also totally changed. GPS has not only made surveying faster but has increased the accuracy to amazing heights. GPS works with the help of satellite systems which provide accurate data directly on the computer screen. Various types of GPS equipment is available, from basic to highly advanced. Some GPS equipment even have night vision which facilitates surveying during the night time. However, it is said that though GPS helps in acquiring the exact position of the land; it does not provide good results in dense forest areas or concrete constructions. For this reason, an instrument known as total station is used along with the GPS.
Total station is a theodolite with an Electronic Distance Measurement Device. Total station has also been one of the reasons behind the drastic change of technology in the surveying field. EDMD shifted the surveying technology from optical mechanical devices to digital electronic devices. In spite of just being distance measuring equipment, total station can also be used for leveling when adjusted in a horizontal plane. Most of the ultra-modern surveying devices are a combination of one or more of these devices.
There is a long list of surveying equipment available in the market today. The selection of particular equipment depends on the type of application and accuracy required. Though all these equipment provide a wide range of options to surveyors, it is advisable to have a thorough knowledge of both, the equipment and the desired survey. This would not only help in bringing accuracy to the work but would also save considerable time and money.