Granite Countertops and GIS

By Art Kalinski, GISP

In the early 1990s when ArcView 2 hit the street, I was at the ESRI Users’ Conference in Palm Springs. I was walking through the poster session area and saw a map that changed my thinking about GIS. In this sea of parcel maps, land use maps, and road network displays I saw a map that “tweaked” my head. It was a map of the human circulatory system that someone did using ArcView 2 – Network Analyst. Network Analyst doesn’t care if the network is an eight-lane-wide interstate or a two-millimenter blood vessel. A network is a network.

That stuck with me and I’ve always enjoyed seeing people think out of the box with regard to spatial technology. This week I saw an example that reminded how far and how broad geospatial technology has come. I use the broad term “geospatial” since I see GIS and computer-aided design merging into the broad world of BIM and geospatial technology. (See my BIM, Son of CAD and GIS article, August 2008).

I’ve been building a mountain cabin that is near completion, needing granite counter tops for the kitchen. Over the years my wife and I had granite tops installed in two other homes, so we were familiar with the process. Since granite is very heavy and difficult to modify on-site, careful measurements are needed. The finished stone, which is fabricated at the factory, has to fit perfectly. Previously, I saw the measurements made by craftsmen fabricating plywood templates, which were then taken back to the shop for actual stone cutting. It was a tedious two-man process as 4-inch strips of thin plywood were cut and glued to form a rigid template.

But things have changed. This time one technician showed up carrying a tripod and small steel box with a computer in it. It was quickly apparent that this was a digitizing device that permitted the technician not only to measure the counter quickly and precisely, but the digital file was then used back at the shop to drive the computerized high-pressure water saw to cut the granite. This reduced what used to be hours of work to minutes.

The digitizer, a Proliner manufactured by Prodim International, was fascinating in its elegant simplicity. Shown here measuring a reception desk, the Proliner principle was a simple process of measuring with a wire. It has a measuring head that rotates in three dimensions with a wire that can be stretched out for several yards. At the end of the wire is a metal measuring stylus. With this measuring stylus a user simply marks the relevant points. The device senses the angle of the wire and length of extension. Simple internal geometric calculations convert these points into a digital CAD file. With the Proliner, a user can measure straight, curved, or complex 3D shapes quickly and with an accuracy of 0.5 millimeter.

I saw examples on the company website of the device being used to measure complex manufacturing projects such convex auto glass, spiral staircase railings, even canvas boat canopies that went straight from measurement to xy plotter/cutters that cut the fabric for a perfect fit. Users can measure any object in horizontal, vertical, or slanting position.The digital drawing can then be fed directly into any CNC-machine or plotter, and the production runs in minutes. In the GIS community, we are doing a similar type of automated measurement using GPS/laser technology to collect field data. At the 2010 ESRI User Conference is saw a demonstration of the TruPulse 360 laser rangefinder with a built-in compass and GPS manufactured by Laser Technology, Inc.

A user can measure the slope distance, inclination, and azimuth to anything, and position any remote feature with just one shot. This unique laser can be pitched or rolled in any direction, and it will still measure the correct azimuth within one degree. Here is just a partial list of measuring applications in use for this technology:

• GIS map feature capture
• Complex infrastructure inside facilities (ladders, agitator blades, etc.)
• Outdoor river/stream monitoring
• Waste water treatment
• Stockpile height
• Molten metal level
• Positioning and detection
• Overhead crane
• Crane avoidance
• Distance between vehicles (mounted in vehicle)
• Steel slab detection and positioning
• Pipe/tree length cutting system
• Camera focusing
• Surveillance detection and camera focusing
• Vehicle profiling
• Fixed point traffic monitor (speed, profiling, length, DBC)
• Truck loading system
• Parking garage system (open spots, illegal parking)
• Bridge height clearance
• Ship docking
• Targeting systems
• In-flight refueling

How does the less sophisticated Proliner get the interest of a GIS professional? Both devices use angle and distance to measure and define points, one with a laser and one with a wire. But what got my attention is “heads down digitizing.” I’ll bet that a lot of you don’t know that the term “heads up digitizing” came from the unused term “heads down digitizing.”

When I started working in GIS everyone was taking their paper maps and getting them into a GIS by digitizing the maps using a digitizing table. This was a table that had a wire grid array imbedded in the table. A user traced the paper map features with a mouse-looking device called a puck. The puck sensed its position based on the underlying grid and sent the digital translation to the GIS computer.

Many of you have never used a digitizing table because by the mid ’90s digital ortho-photography became practical and dominant. Map creation quickly transitioned to digitizing features on an image displayed on a computer screen in a “heads up” position rather than slouched over a table “heads down.” In fact the transition has been so complete that very few GIS operations now have the heavy and bulky digitizing tables in their inventory.

With the kind of accuracy I saw with the Proliner I thought that it might be a way to digitize old paper maps. I called the Proliner USA rep in Florida who indicated that this had been done by several users. So I confirmed that the small tripod-mounted box can be used to trace and digitize paper maps. What would you do if by chance you needed to get an old historic paper map into your GIS? One option could be to call a local granite shop and ask to borrow their Proliner.