Pushing Surveying Beyond Points19 Feb, 2007 By: Kenneth Wong
Trimble introduces the Trimble VX Spatial Station for spatial imaging
The new Trimble VX Spatial Station.
On February 9 in snow-sprinkled Colorado, Trimble, one of the largest survey equipment manufacturers, shuttled a group of reporters and editors from the Westin Hotel in Westminster to the AMC Theater nearby. The journalists were then ushered into a special screening room where Trimble executives had assembled. The premiere event, commemorated with mockup posters inspired by The Matrix and the Indiana Jones franchises, marked the launch of the Trimble VX Spatial Station, an advanced positioning system.
The Star of the Show
Taking full advantage of the cinematic venue, the company's IS (integrated surveying) portfolio manager Erik Schuetz and SI (spatial imaging) portfolio manager Omar-Pierre Soubra engaged the audience through an act of dramatized dialogue, designed to illustrate the tension between the traditional 2D survey workflow and the emerging 3D technology. But the real star of the show was the Trimble VX Spatial Station, an 11.5LB robotic measuring device mounted on a tripod.
Crossbreeding the Trimble S6 Total Station with DR (direct reflex) from the IS portfolio and the GX 3D Scanner from the SI portfolio, the company produced new equipment that combines the accurate positioning capability of the former and the video-overlaying and point cloud capturing technologies of the latter to produce 2D and 3D data sets.
Avoid Too Much of a Good Thing
The Trimble VX spec sheet indicates that the device typically scans at a speed of 5 points per second at a range of 150 meters (492 feet), but can increase its performance to 15 points per second. Trimble executives point out that the Trimble VX's data acquisition rate, though significantly lower than that of the Trimble GX 3D Scanner (up to 5,000 points per second at 200 meters, with the option to extend to 350 meters), is adequate to capture the mass and volume surveyors will usually come across.
Standard survey measurements displayed as points (top) and the same points displayed alongside the 3D point cloud data captured by VX (middle and bottom).
One thing that has discouraged surveyors from using commercially available 3D scanning devices is the massive volume of point cloud data they generate, according to Soubra. "They would often say, 'What am I going to do with millions of points? I don't need that much,' " he remarks. The Trimble VX's configuration, he argues, is designed to capture the point cloud data in a density that's more suited to the surveyors' needs.
Movements, Storage and Display
The Trimble VX's movements are powered by Trimble MagDrive technology, which uses a frictionless electromagnetic system (derived from the method deployed on high-speed trains) to control the optical device's angles and rotations. The device can be operated either remotely or by a cable using a control pad, such as the Trimble TSC2. In other words, even if the Trimble VX is mounted in the desert on a scorching day, the surveyor doesn't need to endure the harsh climate of the site; he or she can collect data from a sheltered area or a van nearby.
The controller pad comes with 512MB of storage, expandable via compact flash cards. 512MB may not seem much in today's gigabyte computing era, but, according to Tim Lemmon, Trimble's application specialist responsible for the live demonstration, it's enough to hold the point cloud data gathered in the field. Soubra further clarifies, "For example, a typical application like a building facade would be around 15MB, which includes the detailed point cloud and the associated images."
The TSC2 controller runs Trimble SCS900 Site Controller software, operating within the Microsoft Mobile 2003 environment. Trimble describes it as a software product "for construction site measurement and stakeout operations," which "measures, computes volumes and loads CAD and surface model files for job site stakeout and grade-checking applications."
The view panel on the controller displays live video feed using the Trimble VISION technology, which allows the surveyor to overlay the points collected on the image of the site. This, Soubra points out, circumvents unnecessary returns to the site -- a common scenario when the surveyor has no way to visually verify whether he or she has collected enough points to satisfy the client's need.
Video overlay makes it easy to determine whether enough data has been collected in the field.
Connect to CAD and GIS via RealWorks
The point cloud data sets captured can be processed and shared in Trimble RealWorks Survey office software. According to Trimble's Technical Notes publication, the software lets you "manage, process and analyze large datasets; easily produce the results you need; easily export to the CAD design package of your choice," such as AutoCAD or MicroStation.
The 3D shapes generated in RealWorks based on the surveyor's point cloud data reflect site conditions; therefore, clients will be able to compare architectural design records and as-built data. On possible uses of this capability, Soubra says, "Comparing as-built condition (existing real-life building) captured by the Trimble VX and the design files of a project can point out a construction mistake. . . . The topography of a terrain captured with the Trimble VX can be used to simulate flooding condition of this terrain and [to determine] what adaptations could be made to protect the property."
Furthermore, RealWorks lets users georeference the dataset by assigning known coordinates to select points. With free applications like Google Earth and MSN Virtual Earth offering 3D terrain navigation capabilities to general consumers, Trimble is betting that its survey devices with integrated 3D scanning tools will drive the market for capturing topology. RealWorks datasets can be viewed by RealWorks Viewer, a free download available from Trimble.
Just as this issue went to press, Trimble acquired INPHO GmbH, a photogrammetric systems supplier in Stuttgart, Germany, for an undisclosed amount. INPHO's photogrammetric products address geo-referencing, digital terrain model generation, ortho-rectifying aerial photographs and 3D feature collection. Now a wholly owned subsidiary of Trimble, INPHO can be expected to contribute its expertise in image processing and LIDAR data processing to developing new products for Trimble's SI division.
"Our business has been primarily focused on ground or terrestrial-based positioning solutions with our integrated surveying and newly formed spatial imaging product portfolios," remarked Ken Spratlin, director for strategy and business development for Trimble. "By acquiring INPHO we have taken the next step in our spatial imaging initiative."
Previously, the French Archeological Mission at Western Thebes has used Trimble's 3D scanning devices to survey and document the current state of Ramses II's tomb. Similarly, R-Scan and NavGeoCom collected 115 million points using 22 Trimble scanning stations over two weeks to capture the 11,733-foot facade of the Russian emperor Oranienbaum's palace for the City of St. Petersburg.
The Trimble VX's entry to 3D scanning also signals the company's strategy to extend its vision to pursue opportunities beyond its current scope of business. If Trimble's calculation proves correct, surveyors may find themselves doing a lot more than collecting points.
Pricing for field-ready Trimble VX Spatial Stations begins at $71,000 (which does not include the RealWorks software).!doctype>