3D laser scanning from NVision made possible a remarkable “collaboration” between two sculptors separated by 160 years. The Southlake, Texas company’s precision scanning enabled artist Hugh Hayden to create a new, 3D-printed, version of John Quincy Adams Ward’s groundbreaking sculpture The Freedman using a digital copy of Ward’s 1863 original as a model. NVision’s scans provided Hayden with a 3D computer-aided design (CAD) file of the sculpture’s highly detailed surface geometry, which he then digitally reworked to create a Freedman for the 21st century.
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An NVision engineer scans The Freedman under the supervision of museum curators and conservators |
Hayden’s work is part of the Amon Carter Museum of American Art’s (Fort Worth, TX) exhibition Emancipation: The Unfinished Project of Liberation exploring the ideas of freedom and emancipation both then and now through the work of seven Black contemporary artists alongside historical artwork. Ward’s sculpture from the Carter’s collection, an homage to freedom inspired by Lincoln’s Emancipation Proclamation, was stylistically trailblazing in the 19th century. Departing from the conventional depictions of African-Americans as powerless it instead presents a classically posed African-American figure not in a state of subjugation but on the cusp of freedom, his chains of enslavement broken. Created in 1863 as the Civil War raged, the then-uncertain status of full emancipation is reflected by the presence of shackles that remain on the man’s wrists.
“In preparation for our current Emancipation: The Unfinished Project of Liberation exhibition, we wanted The Freedman to inspire living artists to create their own work,” explains Maggie Adler, Curator of Paintings, Sculpture, and Works on Paper at the Carter.“ To that end, we invited seven emerging and mid-career Black artists to react to and engage with some of the issues embedded in Ward’s work.” The artists were encouraged to explore Ward’s sculpture through the lenses of their own lives and produce a corresponding artistic statement.
Each artist took the Carter’s prompt in a different direction, with contributions including sculpture, photography, and paper and textile fabrications–but Hayden offered a unique approach: he wanted to make a 3D-printed mold of The Freedman for the modern era, revising Ward’s work to show the original figure in a more contemporary setting.
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The red laser line from the scanner can be seen as it captures surface measurement data from the sculpture |
This presented a tremendous challenge. Traditional casting methods–such as those Ward himself used to copy his sculptures–were ruled out, as creating the mold could compromise the appearance of the museum’s bronze cast and also run the risk of accidentally damaging it in the process. And no form of manual measurement could accurately capture the complex surface geometry and expressive character of the statue.
To create the duplicate that would serve as the basis for his re-creation, Hayden needed the complete set of the sculpture’s dimensional measurements. But how do you nondestructively measure such intricate curvatures and other details–including an engraved tribute to the first black Union regiment on the right manacle–with the required degree of precision?
The museum contacted NVision, a leader in 3D non-contact optical scanning and engineering services with an extensive history of helping sculptors digitize their creations for preservation and duplication. “NVision has made a name for itself in helping much of the art world achieve its objectives,” says Adler. Sculptures from the Metropolitan Museum of Art (New York,NY) the Johnson Atelier Technical Institute of Sculpture (Mercerville, NJ), the Nasher Sculpture Center (Dallas, TX), and “Balloon Dog'' creator Jeff Koons, have all been digitized by NVision.
With the supervision of Carter curators and conservators, NVision scanned the 19 ¾” x 14 ¼” x 10 ½” sculpture using a HandHeld scanner, a powerful portable laser-scanning device capable of accurately capturing 3D geometry from objects of almost any size or shape in precise detail. The scanning was completed in less than half a day. “The NVision team was extremely sophisticated in both making sure that every fraction of an inch was measured and that no harm come to our statue,” says Adler.
The HandHeld scanner used by NVision can capture 60,000 separate spatial measurements per second with an accuracy of +\- 0.025 mm or 25 microns, which is +/- one-thousandth of an inch. (For comparison, the thickness of a human hair is about 70 microns.) This makes it the ideal method to collect data on the complex geometry of sculptural art.
The scanner is attached to a mechanical arm that moves about the sculpture, freeing the engineer to capture the data rapidly and with a high degree of resolution and accuracy. As the laser sweeps the sculpture’s surface, the scanner generates a “point cloud” consisting of millions of points, each with x,y,z coordinates and i,j,k vectors. Every individual point represents a specific geospatial location on the sculpture’s surface. The final point cloud defines the object’s surface shapes and dimensions with an accuracy that outstrips other measurement technologies.
The scanner’s integrated software converts the point cloud to an STL (StereoLithography) polygonal file while intuitive software allows real-time rendering, full model editing, polygon reduction, and data output to all standard 3D packages. The STL file is used to create a 3D IGES/STEP/Parasolid model, which is then converted into the required CAD format.
“NVision created a rendering of The Freedman that is accurate to within a fraction of a human hair, “ says Adler. “Mr. Hayden proceeded to alter the scans in ways that are meaningful to him to make the sculpture his own and 3D-printed the results in white plastic.”
“This project was analogous to reverse engineering projects we do for the aerospace and other industries,” says Steve Kersen, president of NVision. “Those scans provide engineers with 3D CAD files they can use to revise product designs. In this case, it allowed a 21st-century artist to put his own stamp on a sculpture originally created 160 years ago.”
