Cover Story: SEMA

The Ideal 3D CAD/CAM Software Solution

With its software packages, SEMA cover the complete spectrum for timber construction and staircase installation with processes largely standardised to ensure high quality and productivity.

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eliable project planning and creating a continuous workflow on any construction project is vital. One unique aspect that guarantees efficient and smooth working with the SEMA software is its ability to read in and utilise point clouds directly. Point clouds generated with a 3D laser scanner can be imported into the SEMA program and further processed there.

The use of point clouds in the SEMA program results in extremely high levels of security for inventory planning. In conjunction with the 3D measured object and the exact SEMA planning, there are no surprises on the construction site, and everything fits perfectly. The point cloud is read in quickly and smartly – the amount of data is irrelevant. Whether the point cloud contains 3 billion or twice as many points is irrelevant for the performance in SEMA. This is unique with SEMA compared to all other CAD programs.

Stocktaking made easy

The whole process of inventory taking is done with a 3D laser scanner by just one person in a short time. You virtually transfer ‘the entire construction site onto your computer’ because the entire existing building structure is available precisely to the millimetre as a 3D point cloud.

Another time-consuming and costly visit to the construction site with renewed measurement of quantities is unnecessary. The uncertainty of whether everything is correct, and nothing has been forgotten is a thing of the past. Furthermore, an exact documentation of the day of the scan is provided by the complete point cloud. Subsequent changes to the construction site can then be easily verified.

SEMA has set a new standard in the processing of digital 3D data and its further processing in CAD software. The advantages of point clouds – namely the minimal errors of measurement – real measuring of all aspects of the building area, calculation and distance measurements, creation of as-built plans, visualisation of objects and their virtual walkthrough, can be used ideally for planning and construction.

One person that has used this to great success is master carpenter Roger Bihlmaier who has been active in the field of digital measurement for over a decade. He started in 2010 with a classic total station and measurement via individual points, followed in 2014 by the next step with innovative 3D laser scanners and measurement via point clouds.

Thanks to his many years of expertise, Roger Bihlmaier is now an experienced specialist in this field. With his company 3D-Scanwerk,

he covers all areas of digital measurement for his customers as an independent service provider. How does the whole process work exactly?

Making 3D work seamlessly

“In order to record a building with the 3D laser scanner, it requires several scan locations,” says Roger. “These are then merged into a single point cloud. You create a 3D model of the project, in which everything is included: from the exterior view of the building, to intermediate corridors as a link between the exterior and interior scans, all the rooms, in fact everything I scan is then available in just one point cloud.

“I then import the point cloud directly into the SEMA software without any detours. The size of the point cloud is not important in SEMA. You need to know that a 3D scan can quickly accumulate an insane amount of data. Depending on the scan, data can range from several hundred million points for a single-family house to several billion points for larger industrial buildings. “For SEMA, the amount of data is insignificant and does not play a major role in the performance of the program when processing the data. I know many of the common programs for timber construction – but the way SEMA reads in and displays the 3D point cloud, no other CAD program can handle the data so precisely and smoothly and continue working there.

You can plan and design directly in the point cloud in SEMA. Quasi in ‘virtual reality’. All relevant dimension points are picked up in the point cloud. Whether in plan view, in 3D or arbitrarily set horizontal or vertical sections, the dimensions are quickly and easily determined to be able to plan and design further. This can be for a roof extension, a renovation, extensions or even just an extension such as a dormer or a conservatory.

“The approach is ideal,” adds Roger. “Because I have the dimensions and conditions as they are in reality. A crescent-shaped rafter or a sloping house wall in an old building is common, and I can pick up all this information in the point cloud.

Point Cloud advantages

What exactly are the advantages in working with laser measurement and a 3D point cloud? “The inventory is reproduced exactly and to the millimetre, without any deviations,” adds Roger. “With a 3D point cloud, I get reality on the screen. If a wall is crooked, that’s the way it is – and that gives the planner a high degree of planning reliability and helps immensely with the AV. In addition, I can remeasure something in the point cloud at any time without having to drive to the construction site again – that is a considerable time-saver for longer journeys. In addition, the carpenter on the construction site can rely on the fact that everything has been planned exactly and does not have to rework, which in turn leads to higher quality and faster and more accurate work.”

“I know from another SEMA user who specialises in stairs that he always measures twice. He first makes a scan of the rooms to plan the staircase on this basis. For a stair builder as well as for a carpenter, it is very important that all components are manufactured to fit exactly. After the said stair builder has completed his work, he makes another colour scan. He then has the ‘actual’ state of the staircase as he left it with the client – this is perfect documentation. With the second scan, he then has the evidence that he handed over the staircase in perfect condition and does not have to account for it in the event of a complaint.

“The whole thing with laser measurement and 3D scanning is it is great technology and makes a lot of things easier. SEMA has done a great job with the quick and easy import and the super handling of 3D point clouds. Working with 3D scan data in the SEMA program is great fun to this extent because everything is displayed so precisely and works so well and smoothly. You don’t have to wait for an image to build up or for any data to be calculated. The representation of the 3D point cloud in SEMA is uniquely good and really works flawlessly. I am glad that SEMA has developed this function in such a way, it makes my work so much easier.”

For more information on how the software can work for you, email  info@sema-soft.co.uk. Or go to:  www.sema-soft.co.uk