Tuesday, December 3, 2013

Defense of Schools

​Prior to joining the architecture profession, I observed that the design of schools and prisons were starting to converge. Prisons started getting libraries and schools started getting metal detectors. Long have students looked at schools as prisons keeping them from the play and exploration that they desire. A great fear came upon the administration decades ago. The staging of protests, sit ins and teach ins affected the design of schools for a generation. School designs included fewer and fewer windows and increasingly durable exterior finishes. Campuses that once were open to the neighbors, started having chain link and wrought iron fences.

SCRUG 11/2013

SCRUG 11/21/13 Was all about tools for scanning existing buildings.
The presenters were:
John Russo, President / CEO at Architectural Resource Consultants
Nicholas Kramer, Director of Technology at Perkowitz+Ruth Architects
Edward Tallmadge, Strategic Account Manager at U.S. CAD
The history:
• Tape measures, photographs, record drawings, hand held laser
• Static laser, on a tripod, scan, move, repeat
o Each scan takes 5-10 minutes
o Line of sight based
o High level of accuracy
o Reflective and black surfaces are challenges
o In one day a crew of two can make 50-70 scans
• Mobile scanner, auto mounted, uses GPS
o Less accurate than static
o Used for transportation projects
• Mobile interior, +/- 4” accuracy, very fast
• Air born LiDar, less accurate than other methods
Registration – a series of scans must be knit together, match corners that appear in adjacent scans, common physical targets
• Minimum: three common points
• Registration is bringing scans into alignment, a small drift or rotation between scans can compromise the accuracy
Survey control: “total station laser” – use a identification point with a high degree of accuracy, adds cost
Registered scan data is very accurate – can use for walk throughs or fly bys
Processing the data: point clouds can be in the 2-3 gigabyte file sizes, but once created the data may be used for 2D or 3D modeling
Beverly Hills HS: 2D façade study, good accuracy, captured all the detail that would have been dangerous to measure in the field
The Embarcadero: No record drawings available, wanted to create a view & shadow study for city approvals without alerting neighbors, 2-1/2 days for a massing model, $8,000 in 8 days
Beverly Hills Hotel: captures interior detail with a high level of accuracy, custom moldings
OC Performing Arts: point cloud animation, 2 hours to capture data, no targets, 4 hours to register data, ~$3,000 for a quick visualization
Engineering: capture structure, piping, HVAC, accurate to rivets
Contractors: scan before construction, scan during construction, verify plumb, verify flatness, scan a boulder to determine volume
The biggest cost is the modeling of the scans

As part of the laser scanning some models offer cameras and take photos with a second pass. Photos are knit together and then become measurable panoramic 360 degree photos. Manufacturers: Leica & Faro

Light requirements: laser is its own light source, for the digital photos, you need a light source

Short range scanners have a 100 meter range.
Long range scanners have a 300 meter range.

There is a Revit add-on that will place walls and other components when you click on a point cloud.

Photogrammetry – Autodesk Recap 360 : makes point clouds from a series of photos. Upload your photos and their servers will try to knit them together. Free for now. Use a 12 megapixel camera or higher res. You can adjust the registration with the “Pro” version . 2-3” accuracy is possible. Photos may be taken from any digital camera. Overlap images 50-70% for best results. If you want to use a quadcopter w/ GoPro camera, get FAA license & insurance. Entry cost for the quadcopter setup is ~$6,000. Recap does not know what scale things are. You will have to have at least one real world measurement to set the model to the correct scale. Trees & plants don’t capture well.

Podcast with some architecture content...

https://podcasters.spotify.com/pod/show/chris-ganiere