LASER SCANNER
The operation of laser scanners is based on the LIDAR method (Laser imaging, detection and ranging) which allows the precise spatial localization of objects by sending and receiving a laser beam.
Through a mechanism of mirrors, which allow the deflection of the laser beam, it is possible to record thousands of points in space and scan surfaces. The range of the laser beam in the most sophisticated laser scanners is a few hundred meters, while the measurement accuracy is of the order of a few millimeters.
The operation of laser scanners is much more advanced than that of a geodetic station, since it is possible to measure in space hundreds of thousands of points per second through automatic and complete rotation of the instrument around its vertical axis.
The set of these points, which often reaches several tens of millions of points, is called a point cloud, and from its proper processing, architectural plans, orthophotos, digital terrain models and much more can be created.
OFTEN
QUESTIONS
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ANSWERS
How accurate can laser scanner copying be ?
The maximum possible accuracy of the laser scanner impression basically depends on the technical characteristics of the machine, the distance from the building and the type of surfaces being scanned and it can be a few millimeters. The accuracy is not affected by whether it is cloudy on the day of the measurement or if there is total darkness in an area, because it is based on laser technology. On the contrary, other recording methods (e.g. photogrammetric using Matterport type machines), are faster in the field, but have less accuracy and this largely depends on the lighting of the space or environment in which the instrument is located, while they cannot give accurate results when the structures captured are at a distance of more than 4-5 meters. The range of an average laser scanner is 80 meters. Note that the usual photogrammetric methods without special equipment and results control methodology (e.g. Matterport system) have a much lower cost because the cost of buying a Matterport machine is around €4,000, while a good laser scanner is around €40,000, without the fee for an impression with a laser scanner to be ten times that of an impression with photogrammetric methods.
How long does it take to scan with a laser scanner?
The time depends on the particularities of each space (staircases, furniture, physical obstacles, etc.) which can increase the number of required stops for the complete scanning of the space and by extension the scanning time. On average, 2.5 hours are required for an 80 sq.m. apartment. and for a small apartment building about 2 days.
Is it appropriate to use a laser scanner for mapping earthquake-damaged buildings?
The use of a laser scanner for the geometric mapping of earthquake-damaged buildings offers great speed and accuracy of measurement, safety and also a complete and detailed 3D mapping of the existing state of the building. The measurements are done in a minimum of time without disturbing the residents, but also safely because parts of the building that are difficult to access due to height or due to danger can be measured from a distance. The mapping of the pathology of earthquake-damaged buildings is easier and more accurate, without time-consuming on-site measurements. In addition, it is easy to measure even small deviations from verticality (relative displacements) of elements of the supporting body.
Is the cost of scanning and printing high?
If you consider the time you save for the measurements you or a partner would make, the mistakes you avoid and the additional data (photographs, panoramic images, comprehensive view of the space, etc.) that a scan with a laser scanner can provide you, the cost is particularly low. The cost estimate is done on a project-by-project basis after you provide us with some information about the project. If you have a lot of time at your disposal, you are not interested in high accuracy, nor the additional advantages of scanning, or its cost still seems high to you, then scanning with a laser scanner is probably not the most suitable for you. But it is enough to try it at least once in your project to change your mind.
Do you make impressions using photogrammetry?
In specialized cases, such as for example in monumental constructions, we make an impression using both a laser scanner, but also a drone and special photographic equipment to render a high-resolution three-dimensional model with a photorealistic representation of its surfaces. One such case is the photographing of frescoed temples where without their detailed photography with a special camera it is not possible to depict their frescoes in detail only by scanning.
Is it appropriate to use a laser scanner for building impressions to settle irregularities?
A very serious problem with construction malpractice settlements is their capture. These are often inhabited apartments, where there is no luxury of time for long-duration measurements, nor can repeated measurements be made easily. Also, usually these apartments have been built with large deviations from their building permit, without forgetting that in some cases there is no orthogonality of walls, as a result of which their exact measurement is time-consuming. In addition, their load-bearing body must also be recorded in the event that a static adequacy study is required. Scanning with a laser scanner comes to provide a solution to these problems, since in a short period of time and with one visit to the site, the scanning can be done in which the columns and beams (position, dimensions) are captured for the static adequacy study. The engineer also has an image of the entire space through the panoramic shots taken by the laser scanner and can measure dimensions in openings and walls very easily. At the same time, the energy inspector has data on distances and heights from the opposite buildings to calculate the shading that will be used for issuing the energy certificate.
Why is the use of a laser scanner ideal in cases of renovation of business premises/homes?
The laser scanner can provide an overall snapshot of the space in which the renovation will take place, which the architect/interior designer could hardly render with individual photos from his mobile phone or even with a camera. The point cloud produced by the scan includes the entire interior and exterior of the building in a single model that can be browsed by space and measured for openings, walls, furniture, etc. This data is yours forever and is given to you by us no subscriptions (see Matterport's system) or hidden fees or risk of being lost. Everything in the area has been recorded, there is no need for an additional visit from you to measure again or to see something that you did not note or do not remember well.
Do you undertake projects only in Heraklion?
We have undertaken and continue to undertake projects in Crete, but also special projects throughout the country.