How do you provide timely, efficient building and site documentation services for a project that includes over 250 buildings sitting on 600 acres, spanning 8 healthcare campuses in 2 states? That was the question one of our architectural partners was asking when they engaged TrueScan. The project objective was to create accurate building and site documentation for 8 Veteran’s Administration Hospital campuses throughout Indiana and Michigan. The TrueScan team worked closely with the project architect to develop a solution for each campus that included traditional surveying and used unmanned aerial vehicles (UAVs) to generate color orthophotos to document existing site features. Laser scanning was then used to document select portions of the interior and exterior building features. The outcome was a product that gave the architect the information they needed without providing unmanageable amounts of data and, most importantly, within the project timeframe and budget.
The Data Collection Process
The data collection process was divided into two distinct areas, building and site. The TrueScan team worked very closely with the architect to develop a plan for data collection inside the buildings. Site topographic data collection was planned and facilitated by TrueScan’s professional surveying staff and coordinated with on-site VA staff.
The building documentation portion of the project presented a number of challenges because of the immense scale of the task. There were approximately 250 buildings included in the project and close to 6,000,000 square feet of interior space. Scanning that much space within an active healthcare facility with a limited schedule would have been impractical, if not impossible. So, the team worked with the architect and owner to develop a plan. Record drawings for each facility were gathered and used as a starting point for the work. Major exterior portions of each primary building were scanned, providing the architect with an accurate footprint to work from and clearly defining the extents of the buildings. Utilizing the record drawings, the team then identified main corridors, common areas and interstitial spaces which were also scanned and tied to the exterior scans. The combined interior and exterior scans provided the architect with a high precision “framework” of the building from which record drawings and field measurements could be used to build an accurate Revit model of the space. In all, TrueScan performed over 2,600 scans and scanned approximately 2,600,000 square feet of space on the 8 campuses.
Accurate site surveys were also a challenge due to the size of the campuses (some were over 100 acres) and the intricacy of the numerous buildings, walks, drives and especially the complicated network of underground utilities. To address this challenge the TrueScan team utilized GPS to establish horizontal and vertical control based on the State Plane Coordinates. Aerial control targets were placed prior to UAV flights over each campus. The UAV photography was used to generate high-resolution color orthophotos of each site. The orthophotos were not only used as background for each survey but also served to generate detailed planimetrics and to supplement point cloud data for portions of the exterior buildings that were not scanned. The combination of the survey data and information from the UAV flights provided much more information and detail than previous surveys the client was used to receiving for site survey work.
As with any project of this scale, there were numerous challenges, however, two were most significant. The biggest project challenge was simply data management and getting the data collected back to the office daily from remote locations. Laser scan data collected was generally sent back to the office overnight for processing and registration via the internet. Finding a fast and reliable internet connection was critical to the field crews. Our architectural partner was not used to dealing with the file sizes produced from a project of this scale. Care had to be taken to establish a workflow with the architect and work to provide the files in a manageable size for their use. This was a cumbersome process on the first couple of campuses, but it greatly improved as the project went along. The other big challenge with the project was the weather. The majority of the field data was collected between October and March. With the site locations from central Indiana to northern Michigan, winter weather was not always cooperative. Exterior survey data collection is an obstacle for personnel and equipment during extremely cold times or when significant snow was on the ground. To help mitigate this problem field crews started on the exteriors at the sites that were furthest north and worked southward. Data, not able to be collected before winter, had to be collected in the early spring as site conditions allowed.
Ultimately, TrueScan utilized our extensive experience with healthcare projects, a variety of data collection tools and our experience with large and complex projects to help ensure the project was a success. Interruptions of day-to-day hospital operations were almost non-existent, while still ensuring the project was completed on time and on budget.