The technological advancements in the construction industry paves the way for a range of tool inventions. Right now, the designers and engineers are using a variety of instruments for different purposes. However, one of the tools that stands as a cornerstone from ancient land demarcation to modern engineering marvels is the theodolite. Its fundamental purpose is to measure the angles precisely and tailored to specific needs.
In this article by Brick & Bolt, we will delve into the fascinating world of theodolites, their types, and their applications. Read this article to understand the distinct types of theodolites and how they can improve accuracy in your results.
What is a Theodolite
A theodolite is a kind of instrument designed to measure horizontal and vertical angles accurately. It is employed in various tasks such as establishing precise position, locating points, and prolonging survey lines. Theodolites consist of sophisticated telescopes, often used as universal instruments to estimate exact angular measurements. It seems longer in size and has the ability to read minute angular values, even to 1 second of arc.
Types of Theodolite
Theodolites are broadly classified based on their specifications. Here’s a breakdown of its types:
Types of Theodolites Based on Reading Mechanism
These are the classifications of theodolite based on its reading mechanism:
Vernier Theodolite: It is an early form of instrument designed with a Vernier scale to measure angles. Though featuring the least modern specifications, it has been widely used in instructional settings. Unlike other theodolite types, their design is straightforward and provides an opportunity to understand the fundamental functions and components of theodolites.
Micrometer Theodolite: Micrometers are equipped with theodolites to determine more accurate readings than their Vernier counterparts. It is suitable to use in applications where you have a situation to deal with smaller angular values. Due to the arrival of digital advancement, this micrometer theodolite is no longer in use.
Electronic Theodolites: The modernized theodolite contains digital readouts and electronic systems to precisely measure angles. Due to its easy usage, accuracy, and integration with data recording devices, this type has become a prior choice for most contemporary surveying tasks.
Optical Theodolite: The optical theodolite is enabled with a glass arc to read angles. This efficient mechanism reduces parallax error and improves accuracy in measurements. Since the arrival of advanced electronic versions, the usage of optical theodolites has gradually reduced. Still, they become an ideal choice for detailed field measure.
Types of Theodolites Based on the Movement of the Telescope Around its Horizontal Axis
Under this characteristic, theodolites are classified into two different types. They are:
Transit Theodolite: It is a surveying instrument integrated with a short enough telescope that can rotate 360 degrees around its horizontal axis, flipping from face left to right. It has the ability to precisely calculate the measurements of both horizontal and vertical directions. This theodolite type is designed with advanced features and is a preferred choice for modern surveying applications.
Non-Transit Theodolite: Unlike the transit theodolite, the telescope hasn’t rotated entirely around its horizontal axis. Due to this significant limitation, the non-transit theodolites are considered obsolete in modern surveying practices.
Types of Theodolites Based on Design
Theodolite is a specialized instrument developed over the years to meet the specific construction requirements. Below are the lists of types categorized based on the design:
Vernier Transit Theodolite: This is the most widely used theodolite type to measure both horizontal and vertical angles. It is capable of rotating its telescope around 180 degrees in a vertical plane. The integration of the Vernier scale precisely reads angles with a high degree of accuracy, while the telescope is aimed at the target points. The size of this Vernier transit theodolite is based on the diameter of its main scale, which can be 15 or 20 cm.
Tavistock Theodolite: A specially designed instrument recognized for its unique reading method. It is built with the intent of improving accuracy and ease of usage. The Tavistock theodolite is particularly developed for engineering and geodetic measurements.
Watts Micrometer Theodolite: This is a well-known theodolite type equipped with a micrometer to measure fine angular values. It offers enhanced precision for engineering and geodetic measurements.
Wild T2 Theodolite: A legendary instrument influences the field of engineering and site survey industry worldwide. It is planned for a sleek and compact design, providing highly accurate measurements with enhanced durability and functionality.
Wild T4 Theodolite: It is an exceptional design used in advanced surveying work and sensitive geodetic tasks where the most accurate and fine angular measurements are needed.
Applications of Theodolite
Theodolite is used in various specialized applications, and some of them are listed below:
Surveying and Engineering: Theodolite is crucial to measure the angle between points, which efficiently helps land surveys, construction plans, and the creation of accurate maps. It also ensures the alignment of tunnels, bridges, roads, and railways to improve the functionality and structural integrity.
Construction and Building: The theodolite accurately aligns walls and other building plan and structures like corners and columns to ensure proper alignment and structural ability according to the overall plan.
Mining: Theodolite actively helps navigate and map underground mine workings to provide safe and efficient excavation. It maintains the highly precise alignment and direction during tunnel construction.
Choosing the Right Theodolite for Your Construction Project
The selection of the right theodolite is important to construct a structure as you have planned. The digital type of theodolite is efficient to use in large-scale ideas, while the manual type is an affordable option for basic construction projects. Being aware of these factors would help you better:
- Before looking at the instruments, understand your project requirements, including its scale and complexity.
- The next is how precise angular measurements that your projects need to be. Estimate the level of accuracy to choose theodolite type accordingly.
- Site condition is the most significant factor to be evaluated. Consider whether you will be working in a dusty environment, harsh weather conditions, or an area with poor visibility.
- Look at the allocated budget for buying surveying equipment.
- Last but not least, you need data digitally, or just manual reading is sufficient.
Last Few Words
If you are looking to choose the right theodolite, consult a professional to make the right choice. Beyond measurements and alignment, the exact project requirements matter more. Let them check and finalize the right choice that aligns with your specific demand and the scale of your construction project.