Advancements have always been made in modern technology, including the surveying field. Surveying refers to the science (as well as the art) of measuring, calculating, and determining points’ relative positions on Earth. It is about the technique and method to do all those things on the earth’s surface, whether beneath or above. As a result, surveyors can produce maps, which can be helpful for the development of society and civilization.
Among the many surveying equipment used in projects are the Total Station, laser Scanner, and Hybrid of Both. These must-have items will significantly improve the process and positively impact the projects and users. Each instrument has its function and use. So, what are they?
What is Total Station and Laser Scanner?
About Total Stations
They are devices that are generally incorporated in surveying projects and building constructions. Are they effective? Naturally, they are. And they are also helpful. Thanks to them, unparalleled precision and accuracy during measurement process would be guaranteed, and it includes angular and sloping distances.
In general, total stations refer to the tools that are able to measure angular and also sloping distance with remarkable precision and impressive accuracy. The device uses the so-called electronic transit theodolite as well as EDM (short for Electronic Distance Meter) for doing the vertical and horizontal angular measurements. But the device can also be used for taking sloping or straight distances.
The function of the total stations are to make angular measurement. The (electronic transit) theodolite within the total stations can measure the vertical and also horizontal angles accurately. In general, the angular measurement typically ranges, from five arc seconds to ten arc seconds.
Total stations are usually incorporated within distance measurement. The device comes with modulated (infrared) carrier signal emitting and receiving multiple frequencies, so it can determine the most precise and accurate distance (from the target). One device is able to measure distances, up to 1000 meters, and the accuracy is able to reach a level of accuracy up to 1.5 milimeters.
Besides angular measurement, another function of the device is to assist with measurements coordination. It is able to determine the elevation, nothings, and easting of unknown points during the surveying. Showing elevations points’ difference is also another ability that it possess. However, it’s crucial that you understand the coordinate of the area or place that you want to measure. Only by doing so, you can get accurate results from the total station.
As if it weren’t enough, total stations can also be used to generate or process data. After all, this device has been designed with a microprocessor that is built within it. Thanks to this feature, the instrument is able to process the collected data, so users can have better understanding of the results. It’s very helpful in generating a map of the areas that have been surveyed.
How the Total Station Works
Total stations emit microwaves as well as infrared signals toward the prism within your sighting’s position, which is the unknown coordinate. From the prism, the ray would be ‘returned’ to the total station. After it happens, your total station is going to calculate the wave’s speed and also time difference so it can get the angulation and also distance from that unknown sighting.
How to Use One
- Make sure that all of the instruments you need are available, such as tripod stand, cables, controllers, tribrach, survey stake, and others
- Use a nail (or a stake will do) to make the mark of your reference point. You can set the equipment there. Ensure that the position is on the central over the nail or stake
- Set the prism up within the point where you want to measure, and from where the total station is positioned
- Adjust the device (the station) when needed. make sure that the surrounding ground is completely flat. The tripod stand should be established firmly.
- Attach the survey total station equipment carefully on the tripod stand. Connect any necessary cables, such as the controllers or the battery pack.
- Turn the total station on. Use your controller to get precise levelling. Make sure that the total station is flat relatively so the measurements would be accurate.
- Make adjustment to the fine level until your position is precise in order to get exact readings.
- The measurements can be done now.
Benefits of Total Stations
Using the total stations has its own benefits, including:
- The device is pretty convenient and nice to work with. You are able to take multiple surveys which can generate a (simple) location map. You can also measure the distances within short time, while standing only at a location.
- It’s also super accurate. You can use it to measure long distance that is up to 1500 meters with impeccable accuracy and precision.
- It’s fast. It is able to measure angular, sloping, and also straight distance simultaneously while doing coordinate calculations between the measured points altogether.
- It’s quite easy and straightforward to use. You don’t need to have a certain knowledge or experience to operate it. You can easily analyze the produced data by this device too. If you want to, you can download the gathered data to the computer with the integrated CAD (Computer-Assisted Drawing).
Total Stations Types
There are two main types of total stations. The manual total station needs at least 2 people for the operation. As the name suggests, you will have to do it manually. Each part must be operated mechanically. For instance, you need to engage the EDM manually before you can take the measurement (or any of them). You also need to sight or move the prism manually. When you want to lay each point out, you need to manually turn it.
On the contrary to the manual, there is robotic total station. It doesn’t necessarily require any human intervention for measurement taking. The device will follow the prism automatically when it takes the measurement. The device only needs one technician (but it must be a qualified one) for the operation. His/her job is to pair it up with a tablet, so they can work remotely. They won’t need to do any manual operation or whatsoever.
The greater perk of this robotic device is the reduction of possible errors and mistakes during measurement taking. And since the person responsible for the operation (the operator) doesn’t have to do any manual tweaking, they can have better opportunity of the site’s clear view. As a result, they are able to catch and resolve any issue that may arise during the operation, and they can do it quickly.
Considerations in Choosing the Best Total Station
When you want to buy a total station, you need to consider these elements or features.
- Different types will come with different accuracies. Some devices have 0.5’ arc second with 0.6mm distance accuracy, while others may come with different figures. The previous one means that the device is super accurate. Go with the level accuracy that you prefer.
- Measured distance ability. It’s crucial that you go with a device that can do long distance measurement precisely. The general total stations today are able to measure between 75 and 1000 meters, but some of the most sophisticated ones are able to do it up 1500 meters.
- Software capability. Go with a device that can help you with efficient work, being updated to the latest technology. Modern devices are commonly able to gather data, process it, analyze it, generate map from the data, and be connected to the computer. They can also send the info automatically for further data processing or others.
- You want to choose something that is lightweight without compromising performance or quality. Your movability won’t be compromised because of the unnecessary weight.
About 3D Laser Surveys
When we talk about laser scanning survey, we talk about accurate and fast way of getting an existing building (or other structure) spatial detail. The device implements the newest and most modern laser scanner (the high definition one) to get accurate geometric data in that build environment, both for the interior and exterior. This will create a point cloud, which will be turned to 3D model.
Who would use the 3D models? Construction design teams, property developers, and architects will use them as experiment tool. They can also make plans or record changes to the existing environment. It will help with Building Information Model (BIM) process.
The Technology of Laser Scanner
This device implements LIDAR (Light, Imaging, Detection, and Ranging) technology. It will capture spatial data (usually in big amount) faster than the traditional surveying ways or methods. LIDAR tech is able to emit energy beam and then calculate the coordinates for every physical contact’s point.
The device is able to survey a building exterior as well as interior within seconds. It’s able to get the features’ precise location. The data (from the laser scanning) can be used to make accurate 2D plans or 3D digital models.
Types of Laser Scanner
- Phase-based laser scanner. It will emit laser pulse and it will then compare the shift of the phase wavelength between the stored value and returning pulse to calculate how long the beam travels. Basically, it calculates the travelled distance.
- Pulse-based scanner or time of flight. It calculates the time needed for the pulse to get into the object and then get back to the scanner. It will then determine the precise distance.
The Hybrid Instrument
Is it possible to combine 3D laser scanner and total station? It’s highly possible. In fact, there have been some devices that have both combined technologies although there aren’t many of them.
You have learned about the benefits of each device. Imagine how powerful it is to have one device that can do various functions. Known as the hybrid 3D laser scanning total station, this device is perfect for various projects, including mining, forensic applications, mining, and surveying. And the best thing is: it can be operated by one person.
Surveyors generally use the ‘traditional’ EDM within the total station for scanning. But with the new hybrid device, they can do it faster. After all, the new device has two different technologies that work together in user-friendly ecosystem. The total station’s accurate optical measurements can be supported or complemented with the scene’s 3D scans – and the process is done in efficient and quick manner.
You see, when users make use of the EDM technology to do laser scan, the performance of the device would be compromised. It would be slow and sluggish. However, when you combine both total station technology with 3D laser scanner, you can get 3D scan results quickly. It will boost the traditional and slow survey measurement.
In most cases, the hybrid device can be used for various applications and usages:
- BIM and for (as-built) verification. You can use it to document the build and verify it within each stage
- Provide feature and also detailed surveys for infrastructure and roads. You will be able to get detailed and better informed overview that may cover road lines, power lines, utility assets, street signs, and others. The best thing about it is that you can do it without having to deal with risk safety or close the road down.
- Underground and tunnels mining. It would provide pick up (and detailed) measurements with all structural features and assets with 3D laser scanner.
- Forensic surveys. It can get you comprehensive scene’s insights through total station measurements’ combo, 360-degree of photography, and 3D model.
When you have surveying projects, you need to think about what they are all about. Different projects have their own types, and each type will determine whether you need ONLY a 3D laser scanner, only a total station, or both. The hybrid total station can be done for topographic and boundary surveys. It’s like the Swiss-army version of a surveying instrument.
In the end, only you can decide whether you need a standalone Total Station and Laser Scanner or the combination of both. After knowing the facts about Total Station and Laser Scanner , and the hybrid of both devices, which one suits your needs the most? You can get all of them, including the hybrid tool, although your options may be limited when compared to other devices.