The world’s most complete digital twin of Alcatraz

The story behind capturing the biggest set of 3D scans of Alcatraz Island

The US island prison Alcatraz is a unique environment. The rugged 22.5-acre site of the notorious jail has now been digitally captured in unprecedented 3D detail, involving a world-leading project deploying multiple mapping technologies. Having camped in the jail’s infamous cells for three weeks during the cold San Francisco winter, project head Pete Kelsey and team member Dr Jeremy Sofonia tell us the backstory to this hugely significant endevor.

Planning for Alcatraz

Pete Kelsey discusses the project objectives, why having a digital twin of the entire site was important to the Park Service and the many ways the data could be repurposed. He details the huge amount of pre-planning that was involved to ensure the project was a success – from getting permits to assessing which technology the team was going to deploy, to accurately and safely mapping every single space on the island in just 3 weeks – and why the Hovermap ST-X was the right tool for the job. Also hear about how the team overcame access challenges that included minimizing disruption to Alcatraz visitors, and how the project was managed on a day-to-day basis to ensure everything was going to plan.

Mapping the ‘Rock’

Jeremy Sofonia discusses the project origin and how it evolved from creating a virtual tour to developing a 3D model that would be used to monitor the site and plan maintenance and restoration works. Hear about the challenges of a typical day and how the team overcame the complexities of mapping the site, such as dangerous, dark, and difficult to access areas, by applying different scanning techniques. The sheer volume of data was immense and Jeremy details how the data was validated as it was captured. He talks about the workflows and structures that were put in place to process, manage and merge the data across multiple computers to ultimately deliver one accurate, detailed dataset of the entire site.

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