Wednesday, April 13, 2011

Featured Project - Digitally Preserving the Lincoln Memorial

Preserving America's National Monuments

In honor of the Civil War Sesquicentennial we'd like to talk about a scan project that we were privileged to participate in: the 3D scanning of the Lincoln Memorial.

A few weeks after September 11, 2001, representatives from the U.S Government approached Direct Dimensions with a very special request. For obvious reasons, various agencies and organizations had suddenly become interested in documenting significant American cultural landmarks, monuments, and structures in case of similar catastrophic events. The group asked Direct Dimensions to demonstrate its developing capabilities for 3D laser scanning and digital modeling and they even offered up the Lincoln Memorial for this effort.

The DDI scanning team mobilized for a planned one day on-site demonstration on a rainy chilly day in late December 2001 for a broad audience that included high ranking officials from the National Park Service, the Smithsonian Institute, the Architect of the Capitol’s office, and the Historic American Buildings Survey.

Using a portable long-range spherical laser scanner mounted on a tripod, they gathered millions of 3D data points from nearly twenty different scan positions focused mostly on the front entrance area of the Lincoln Memorial and the main interior chamber containing the famous sculpture. During each scan, the system captured thousands of XYZ data points per second yielding a real-time 3D picture of the scene with accuracy to about +/-6 millimeters (0.25 inches).

During the next several weeks back at the Direct Dimensions facility in Baltimore, the team processed the raw scan data sets into a 3D mesh model using PolyWorks software. They also incorporated some of the traditional blueprint architectural records provided for the facility. This resulting 3D digital model ultimately included the front steps of the Lincoln Memorial, several of the front columns, elements from the main interior chamber, and of course much of marble Abe Lincoln seated on the marble throne.

To further demonstrate the potential and value of capturing such important artifacts in high definition 3D digital media, Direct Dimensions collaborated with the U.S. Army’s Advanced Digital Manufacturing group at Aberdeen Proving Ground to fabricate a 20-inch long scaled physical reproduction using rapid prototyping, or 3D printing, of this Lincoln Memorial model including the sculpture of Abe Lincoln. Making this physical model demonstrated the ability to not only capture the complex shapes digitally, but also that the artifacts can be reproduced physically using computerized manufacturing technologies.

Direct Dimensions is proud to have performed this project and has continued advancing its capabilities and technologies for accurately capturing such precious artifacts. Please visit our website at to learn more.