Artec Space Spider scans gigantic 150-million-year-old Stegosaurus skeleton

Product: Artec Space Spider
Industry: Design and Art

One of the most iconic scenes depicted in a dinosaur exhibit has to be the Stegosaurus and Allosaurus facing off in the Denver Museum of Nature & Science. The 26-foot-long Stegosaurus represents Colorado’s State Dinosaur. Not just the species of dinosaur, but the individual specimen that was adopted to represent the state. Stegosaurus was a herbivorous dinosaur weighing up to 10 tons that inhabited the area now called Colorado 150 million years ago. What makes this particular Stegosaurus so special is not the fact that it was found in Cañon City, Colorado, or even that it was mostly complete, a very rare thing for dinosaur skeletons. It was found by a class of high school students on a fossil-hunting field trip in 1936, and the teacher of that class of students, Frederick Carl Kessler, was able to arrange for his students to work alongside professional paleontologists to excavate the fossil skeleton.

Enter Mike Triebold of Triebold Paleontology, Inc. (TPI) in Woodland Park, Colorado. TPI restores and mounts fossil skeletons and creates skeleton casts, supplying them to museums across the globe. The company’s clients include the American Museum of Natural History in New York, Carnegie Museum in Pittsburgh, and the Smithsonian Museum of Natural History in Washington, D.C. The TPI headquarters house a collection of casts and original fossil specimens, which are on exhibit at the company’s hands-on natural history museum, the Rocky Mountain Dinosaur Resource Center.

Mike Triebold was looking to add a Stegosaurus to his catalog of casts, but not just any Stegosaurus. He was focused on getting the famous Kessler Stegosaurus at the Denver Museum for the project if at all possible because the new Royal Gorge Dinosaur Experience in Canon City was being built and they wanted a copy of the Stegosaurus that was collected by Kessler near Canon City.  RGDE owner Zach Reynolds’ grandfather regularly accompanied Kessler on dinosaur digs from the 40s through the 60s, so the Stegosaurus has both family and community ties.

Discussions ensued and with the Denver Museum’s blessing, the work began

Reproducing this specimen was complicated by a couple of factors. One is the size of the specimen. Not only is this dinosaur over 26 feet long, but with the tall plates lining its neck, back and tail, it is also over 9 feet tall. Normally the size would not be an insurmountable challenge as each individual bone would just be molded in silicone and cast from liquid plastics. This specimen is not just bones on shelves though. It was mounted and placed on exhibit in the 1990s using purely permanent means, so it was not built to ever be taken apart. Steel was shaped around the skeleton, welded in place, and permanently puttied to the bones, so molding the individual bones in silicone was rendered impossible.

To recreate this specimen TPI’s Matt Christopher needed to mold it using 3D scanning. “We needed to three-dimensionally digitize the skeleton that could not be dismantled so that a replica could be 3D printed,” says Matt. “The dimensions and surface details needed to be close enough to what we would get from a silicone mold so that we could hand-finish 3D prints to look exactly like the original specimen.”

TPI used Artec Spider structured-light 3D scanner along with Artec Studio 3D scanning and processing software for the job. The scanner was supplied by Artec’s local partner 3D Printing Colorado. “Our Artec Spider captured exactly what we needed,” says Matt.

Spider was used to scan individual bones and regions of the skeleton as individual projects in Artec Studio. “This involved crawling inside the rib cage (yes, a full-grown person fits inside the rib cage of Stegosaurus) to capture the dorsal vertebrae forming the dinosaur’s back and the medial surfaces of the rib cage, shoulder blades, and hips,” says Matt. “There were also some interesting poses taken atop a step ladder to reach the tops of the big fan-shaped plates on the dinosaur’s back. We were able to capture all of the elements we needed, from the tip of the nose to the huge spikes at the end of the tail.”

The team ended up with 629 individual scans across 71 individual scan projects in Artec Studio. The number could have been higher, but in order to save time it was decided to skip scanning the elements that could be mirror-imaged to generate the other side, like the arms, legs and ribs.

Each scan needed to be aligned, cropped, and converted to 3D mesh files in Artec Studio. “The alignment features in Artec Studio were absolutely paramount to the success of this project,” says Matt. “Aligning each scan was as simple as manually orienting to a loose approximation of the correct position and letting the alignment tool refine the fit to perfection. Using Artec Studio to create and control the mesh generated from the aligned scans allowed us to extract the exact level of detail we wanted for manipulating and 3D printing.”

Exported meshes were free of artifacts thanks to a filter in Artec Studio that removes all elements smaller than the master scan. Small holes were automatically filled using the hole filling algorithm in Artec Studio. “Had we been scanning individual, unmounted bones, it would have been easy to generate complete, watertight meshes directly out of Artec Studio that would have required no additional post processing” says Matt. “With the steel armature remaining to be removed and the obstructed surfaces left to be reconstructed, watertight meshes were not really an option or a necessity for remaking the Stegosaurus.”

The resulting meshes were imported into ZBrush for separation of articulated elements, reconstruction of surfaces that were impossible to reach with the 3D scanner, like the spaces between articulated bones, and removal of the steel armature that obscured some bone surfaces.

TPI has a variety of 3D printers at their disposal ranging from a small Formlabs Form2 SLA desktop unit to a large-format Atlas from Titan Robotics. With numerous printers working on the project, printing the skeleton required six months. As the prints were finished, they were lightly resurfaced by hand and prepared for molding by adding mockups for internal steel armature and articulating some specimens to be molded in sections rather than as individual bones. Each completed bone or assembly is called a master. These masters were then molded in silicone rubber using high quality liquid silicone rubbers in two-part to multiple-part molds; something TPI staff has been doing for nearly 30 years.

The finished molds were then fitted with internal steel to be surrounded by plastic resins in the casting process. “The plastic is poured around the steel, so no external armature that would hide bone surfaces is needed,” says Mike. “With the casts poured around the armature, we can assemble the skeleton in any one of an infinite number of poses and weld together the steel protruding from inside each plastic cast. The mounted skeleton is then ready for hand-painting and delivery.”

With the project now completed, it will be on permanent display at the Royal Gorge Dinosaur Experience (  www.dinoxp.com ) in Canon City, Colorado, being unveiled on Saturday, May 19th. Zach Reynolds, his family and dad Dave will now be able to share the fulfilment of this important wish with the public for years to come.

According to Mike, this project would have been impossible to complete a couple of decades ago. “With our Artec Spider we were able to marry the best technologies of today with the most advanced traditional methods of molding and casting to create an exact copy of that great dinosaur without even touching it,” he says. “Now, how about that Allosaurus…”

Artec SDK for a faster automated, error-free robotic scanning process

Product: Artec Space Spider
Industry: Academic

An international group of researchers have used Artec Scanning SDK and Artec Spider mounted to a robotic arm to develop a new automated scanning method which produces 3D scans of great quality even when scanning small objects with complicated geometry. A number of comparative tests have proved that the new method effectively outperforms previous scanning techniques.

3D scanning physical objects may present quite a large challenge, especially when the object has a complicated texture and occlusions. There has been a great deal of research carried out to eliminate the amount of damaged data and blind spots in resulting 3D images, and one team has come up with some really impressive results.

A new scanning method has been devised by a group of engineers from Visual Computing Research Center, Tel-Aviv University, the Memorial University of Newfoundland, the University of Konstanz and Shandong University.

In a series of experiments, the researchers used Artec’s 3D scanner fixed to an arm of an anthropomorphic robot, PR2, to scan a number of small objects placed on a resin table that the robot held and rotated in its other hand.

For their experiments, the team chose Artec Spider over other 3D scanning solutions. Spider is an ideal tool for scanning small objects since it sees even the sharpest edges and very tiny parts.

Spider produces images of extremely high resolution (up to 0.1 mm) and superior accuracy (up to 0.05 mm), capturing up to 7.5 frames per second and processing 1,000,000 points per second. The frames are fused in real time, meaning that no complicated post-processing is required.

Together with Artec Studio 3D modeling software, it is a powerful, desktop tool for designers, engineers and inventors of every kind, and with Artec Scanning SDK, it can now be incorporated into any specialized scanning system.

The main objective of the experiments was to ensure high fidelity scanning of the objects. This goal was achieved by placing the scanner at strategically selected Next-Best-Views (NBVs) to progressively capture the geometric details of the object, until both completeness and high fidelity were reached.

The idea of the new autonomous scanning system boils down to the analysis of the data acquired by the scanner and the generation of a set of NBVs for the scanning robot.

The scanning process starts with a blind, all-around scanning of the object to obtain an initial point cloud that roughly covers large portions of the object’s surface. Then a set of NBVs, or candidate viewpoints, is generated based on the screened Poisson equation.

The robot then moves the scanner so as to take snapshots from these viewpoints. When the robot’s hand holding the scanner has reached the assigned viewpoint, a scan is made. The system obtains the frame, which is then registered and merged with the initial image.

To avoid losing detail, the new algorithm creates a confidence map, accurately detecting low-quality areas where additional scans need to be applied.

The scanning process was programmed using Artec’s Scanning SDK. The scanning takes place automatically and stops once the specified reconstruction requirement has been reached.

The new algorithm was compared to two other NBV-based algorithms, one focused on visibility and the other one on boundaries. The new approach proved to provide higher quality of scanning.

The researchers also compared their algorithm to curvature- and density-based approaches to again show that their method delivers scans of unparalleled quality.

In addition, the team experimented with their algorithm on another robotic platform, a one-arm industry robot to automatically scan a delicate elephant object at high quality and high fidelity.

Scanning pizzas fresh out of the oven with Artec Space Spider

Product: Artec Space Spider, Artec Studio
Industry: Consumer Products

When they take the pizza out of the oven, the last thing you think about is scanning it in 3D. But that’s exactly what a 3D scanning specialist did in Poland. Hours earlier, his client, the NuOrder advertising agency in Warsaw, received a call from Da Grasso Pizza, one of the most popular pizza brands in the country.

Da Grasso wanted to create animated ads for her different pizza styles, but there was a problem: how to make the pizza look as delicious as in real life. 3D modeling was quickly brazen, as it could not realistically represent all the organic shapes and surfaces of a Da Grasso pizza and its many ingredients.

That’s when NuOrder knew that 3D scanning would be ideal for the project. They contacted the Ambassador of Artec of Warsaw 3D Master to tell him the requirements of the work. 3D Master has many years of experience in a wide range of 3D scanning and printing applications, including CAD design, technical consulting and more.

For the Da Grasso Pizza project, 10 high-resolution 3D color pizzas would have to be scanned, with enough detail to show off each slice of pepperoni, onion, shiny olives, as well as its golden crust and layers of melted cheese.

Also claiming, 3D Master reverse engineering specialist Adam Rajch knew Artec Space Spider would be perfect for the task. With an accuracy of 0.05 mm, and capable of capturing incredible levels of detail in a single pass, this handheld 3D scanner has proven extraordinary for small objects in fields as diverse as quality control, reverse engineering, healthcare, forensic medicine, and other fields.

Rajch got going when he touched scan. The photo studio where the scan was performed has its own oven, which made it possible for the pizzas to be scanned at the right time. Just after leaving the oven, Rajch carefully divided each pizza into eight portions of the same size, making sure to separate them approximately one inch (2-3 cm), to allow the capture of the edges of the pizza.

From that point, it took a total of 5 to 7 minutes to scan each surface of the pizzas and all those irresistible ingredients. No sprays or markers were used in the scan. However, because the cheese was so juicy and sometimes made the surface too reflective to scan well, Rajch had to gently clean the pizza with a paper towel to absorb excess fat, making scanning much easier.

Rajch then processed the scans in Artec Studio. He first used the global register, followed by sharp blending, then simplification of the mesh by precision, and filling gaps when needed. All that was needed was to add the texture, and the 3D models were ready to be exported as OBJ files.

Once the NuOrder advertising agency received OBJ files from 3D Master, they launched their creative gears, short film specialists, 3D animation of products and TV characters responsible for achieving great results at affordable prices for sales and marketing campaigns.

NuOrder’s team of animation specialists used 3ds Max, as well as Adobe Photoshop, After Effects, and Zbrush to build the ultra-realistic 3D models and prepare them for the animation sequence. Loose elements of pizzas, such as arugula leaves, olives and cherry tomatoes, were incorporated separately.

NuOrder Creative Director Daniel Dudek described the project as this:

“We collaborated with 3D Master to create the 3D pizza scans needed for the Da Grasso spot. The challenge was that the pizza not only had to look appetizing, but the file sizes had to be optimal for the models to be easy to work with and to be able to animate in the end. Because the customer is a chain of pizzerias, photorealistic results and aesthetics were the top priority.

“In the end, the 3D scan turned out to be better than the product photo shoot. We are delighted with the result.”

You can see the results in the video: