Branching Out With Point CloudsNew Opportunities and Applications for 3D Laser Scan Data

A 2.057Mb PDF of this article as it appeared in the magazine complete with images is available by clicking HERE

Terrestrial laser scanners and "reality computing" technologies continue to be an effective tool within a diverse group of industries ranging from building renovation and historical preservation to law enforcement and video game design. 3D scanning has an established track record in construction and forensics, yet its application in many other fields remains in its infancy. Laser scanning applications are limited only by our imagination. It is likely there are still countless overlooked trades and industries yet to benefit from this emergent technology.

One example is the timber industry, but perhaps not necessarily in a way many would expect. As more industries take part in the "Green Movement," companies look for sustainable ways to maximize materials while minimizing waste. A notable example is a Midwestern company specialized in using small diameter timber in place of steel in residential and commercial construction. Round timber (whole diameter tree trunks or unmilled timber) uses the entire circumference of a tree (often including large support branches), minimizing wasted material. By choosing not to square and cut timber the traditional way this company can utilize abundant small-diameter timber, and at the same time protect old-growth trees.

The company looks for specific tree shapes for a variety of structural applications. For example, Y-shaped trees can be used as columns or supports, while bent or arched trees can be used for doorway framing and cathedral ceiling bracing. Furthermore, elaborate branch-work can be interwoven into handrails and banisters for stairways. Both deciduous and coniferous trees are used. Certain trees, like Ash, Black Locust, and White Oak are valued more for their strength, while Red and White Pine poles are valued for their straightness. Unusual and oddly-shaped trees are sometimes chosen for aesthetic reasons, providing both functionality and a natural artful flair.

TURIS Systems was approached by the company with an unusual question: Have you ever laser scanned trees? As it happened, we had; intentionally even. A few years ago we scanned the edge of a large wooded campus to determine which trees (if any) would be affected by a road-widening project. The trees were very important to the property owner, so project engineers had to be careful not to disturb or damage the trees’ root systems during road excavation and widening. Trees were modeled directly from the point cloud scan. Root systems were estimated based on tree size. As a result, we were able to create a path for the road that disturbed as few trees as possible.

Our structural tree client had something entirely different in mind. The question was this: Could TURIS laser scan trees to document their shape and size? And if so, could a scanned tree be brought into Autodesk’s Revit software and compared with pre-made Revit families of commonly used tree types and shapes? If this proved feasible it opened the door to other possibilities. For example, it would also provide architects and designers the ability to navigate 360 degrees through point clouds of wooded lots to search for specific tree types or shapes applicable to their project, all from the comfort of their desk, wherever that may be.

Finding the Right Tree for the Job
Once trees are selected for a project they can be modeled directly from the point cloud using Revit. From there tree models can be linked into a project and placed wherever they are needed in the model. Having models of actual trees takes a lot of the guess work out of the normal building process. However, in some cases models may not even be required, as tree point clouds can be linked into the model purely for visualization purposes or for acquiring measurements.

Additionally, young trees showing promise can be modeled using SpeedTree software, a software package normally used for film and videogame design. Of course forests are not static objects; they grow and change through the years. That’s fine, because this software can simulate tree growth patterns and estimate size and shape over time. By using SpeedTree’s growth simulator designers can predict when a tree will reach the optimum age or size desired and plan a harvest date years in advance. Granted, we are still in the testing and development phase, but SpeedTree may enable our client to predict and quantify their future inventory and improve preparedness for future projects. Of course testing the efficacy of this process will take time.

Tree Tracking and Data Management
We also proposed an idea to our client about using QR codes for accessing and tracking tree data. Trees could be given durable QR code tags that link to online documents containing specific data associated with each tree. QR codes can be attached to trees before they are even cut. Next, stands of trees are laser scanned (either while still growing or cut in a warehouse with QR codes visible).

After scans are registered a project file is created using the WebShare feature of FARO’s SCENE software. A link to the Webshare data can be provided to architects or designers. Webshare files contain 360 degree high-resolution photos taken from each scanned location. The software allows users to navigate around in the photos like a virtual tour. Users can zoom in on areas of interest for more detail if they choose. If users see a tree that looks useful to their project they could zoom in on a notation added next to each QR code within Webshare. Clicking the notation will pop up a QR code with a link directing the user to an online storage site where they can download all related documents specific to that tree. Users can click the link or scan the code with their phone.

The ability to track and manage large quantities of inventory and long-term asset documents requires software that is flexible, collaborative and simple to use. TURIS is able to assist our client through the use of another software: AkitaBox, a solution for managing any type of information in the design, construction, and facility management arenas. The software enables our client to find documents and locate specific inventory items quickly via tagging and advanced searching. For example, our client can track and record a myriad of tree types and categories among available trees (or future stock) by tagging files according to:
Geographic coordinates
Shape classification
No. of Central Branches
Spread Width Range Base
Circumference Range
Crown Height Range
Stem Height Range
Total Height Range
Hard or Soft Wood
Min-Max weight load
Green or Kiln-Dried
Inventory date
Projected Harvest Date
Specific Item# or Project#

Files can be shared with other designers and trades allowing enhanced project collaboration and streamlined coordination. Documents can also have different levels of edit permissions for added project security. Using the QR code example, scanned QR codes can link directly to documents archived on AkitaBox.

Tree Customization
Some trees’ shapes are guided and controlled as they grow to conform to an unusual or specifically desired shape. Tree-shaping techniques have been around for hundreds of years and are known by a few names, like arbortecture, biotecture, or pleaching. Some amazing examples include living root bridges built by the Khasi people of India. In North America, Native Americans used to shape trees by bending them to point in a desired direction to mark trails. Some very old and famous "trail-marker" trees still exist today. The tradition of tree-shaping still has applications today. In the case of our client, their arborists can access data in the field that is unique to each tree, including plans, projected timeline, instructions, and details for shaping the tree, via the tree’s unique QR code.

Our client is also interested in purchasing uniquely shaped trees of varied species from private sellers living in urban areas. It would not be cost effective to go out and laser scan trees on a one-by-one basis. However, private sellers can take a series of photo images 360 degrees around a tree they wish to sell. TURIS can then take those photos and process them using photogrammetry software to produce a 3D point cloud of the tree. The point cloud file can then be appropriately tagged, organized, and securely stored inside AkitaBox.

Our relationship with our client is still a work in progress. Therefore we do not have specific project data on efficiency or cost savings; but early indicators look very promising. We feel the company’s unique niche in the building and timber industry is ripe for utilizing reality computing technology. As the process continues to develop it is likely we will discover additional applications for point cloud data, making the technology even more valuable for future projects.

Kevin Nelson works for TURIS Systems, an international technology consulting group in Madison, WI. His primary focus is discovering new applications for reality capture technologies.

A 2.057Mb PDF of this article as it appeared in the magazine complete with images is available by clicking HERE