Development & Planning with Google Earth

I honestly had not thought much about Google Sketch Up until Wednesday morning. It’s a nice enough 3D drawing application, easy to use, as far as it goes. It even has a snappy photo draw feature. Import a photo, identify the sight lines and horizon, and start tracing. Sketch-up knows enough to create a model from your tracing.

You cannot, however, do anything too sophisticated with it. You cannot interact with masses. You cannot get any BIM out of it. I felt it was an interesting sketching tool, and nothing more. I was not very interested.

Of course, I had neglected the benefit of network effects, failed to take into account how easy connections between systems create new value, value beyond that of the system itself.

One of the network elements is Google 3D Warehouse. 3D warehouse is, at first glance, a YouTube of models drawn in Sketch Up and submitted to the warehouse. One’s chance of finding something useful is limited by the accuracy with which the submitter tagged the sketch. There are many 3D cats, an eerily life-like disembodied head of Barak Obama, and so on. Manufacturers have uploaded a large library of 3D objects that you can include into your models. There is also a growing library of actual buildings in the 3D warehouse.

Sketch-Up also uses its shared heritage with Google Earth to eliminate the positioning or “origin” issue of most low end building drawing programs. Most drawings are at the center of their universe. This makes combining multiple drawings is hard. Sketch Up drawings are all located in space. You can select a town, or you can place your drawing at a latitude and longitude. Initial daylight analysis is almost effortless.

One final network effect was the interaction with Google Earth. You can pull up, say, an intersection in using Earth. From Sketch Up you can then grab the site and place it your building sketch directly on it. When you are done, you can post your building directly back onto Google Earth and share it with others.

Well now, this is different. Zoning and public planning processes can now be performed in shared real time using only free tools. Public access, including public submissions, can be straightforward in this environment. Community groups and planners can work from the same models, visualized the same way, with computers they have already.

Complex interactions between buildings can be explored. A new building might cast a shadow, or a wind shadow on an adjacent building. Does this increase heating requirements? Does it reduce on-site generation capabilities? Does it instead reflect more light on the existing building, causing increased heat load?

Zero Net Energy buildings will be concerned with energy interactions at this level. Early easy visualization might let us notice these interactions early in our processes, so we can plan for them.

Field BIM: RFID and the transformation of the Job Site

Monday at FIATECH I learned about Field BIM, using BIM to bring lean manufacturing techniques to the job site. The approach was illustrated using a case history of the ongoing construction of Giants Stadium.

The new Giants stadium was entirely designed in BIM, meaning that complete three dimensional objects for the entire stadium were known in advance. The major structural components are a steel frame and pre-cast concrete forms. In essence, the largest issue on site is the most efficient assembly of these pre-existing modules. Examples of complicating issues are that erecting the steel frame for the upper decks would block access of cranes to lift inner pre-cast units into place.

An additional challenge, one that turned out to be an opportunity, is that the new stadium is collocated with the existing Giants stadium. This meant that the site staging was severely limited, as job site and parking for the old stadium were in direct conflict.

The team set up direct data exchanges between the scheduling system, the BIM software, the job site management system, and augmented it all with RFID tags. RFID (Radio Frequency Identification) is the name for the tagging technology that is used for inventory control in modern stores and warehouses.

Using the 4D BIM (BIM over Time), the team created an optimum sequence for assembly. This work was shared iteratively with the project management system, until a plan that the construction team could commit to was finished. This schedule was transmitted to the fabrication companies creating the pre-cast concrete. This schedule was also synchronized with the job site management software.

The fabrication plants received all forms as templates in CAD, and the delivery dates expected for each component. Just as in lean manufacturing, the agreements allowed no product to be shipped to sit until they were needed. This, by itself, improved efficiency because all on-site inventory was easily visible.

One of the requirements for the job was that an RFID tag was cast into each pre-cast module. This tag was then scanned and associated with the matching module in the job site scheduling system, which was them marked as “Manufactured”. The tag was re-scanned at the key stages of the module life-cycle: QA Inspection, Shipped, Received, Inspected (again), Erected, and, occasionally inevitable, Damaged.

This approach enabled the construction managers to anticipate problems at every level and prevent changes to the schedule. When looking ahead, the manager relies on the assembly schedule prepared in the 4D BIM. Looking ahead, the expediter could see instantly which materials needed in the next week were on site or en route. With only the materials about to be installed on-site, inventory and hunting time were minimized. As each module is scanned during installation the current state of the construction gets updated automatically, and re-synchronized back into the BIM.