Manitoba, which is part of the vast North American prairie, is prime real estate for wind. So an independent power provider, Algonquin Power, is building windmills to generate electricity at St. Leon, in the southern part of the province. If all goes as planned, the site will eventually contain 63 wind turbines from Vestas Wind Systems of Randers, Denmark. Algonquin, which is based in Ontario, estimates that the wind farm will average about 370 gigawatt-hours a year.

Manitoba Hydro, the province's electricity provider, has a 25-year contract to buy the power.

There are a dozen Vestas machines set up now, and Algonquin is studying how they perform before installing the rest.

Manitoba wind power: A university is testing ways of overcoming losses due to ice on the blades.

Tests are being conducted on site and in a wind tunnel at the University of Manitoba, where research under Eric
Bibeau, the Manitoba Hydro/NSERC Chair in Alternative Energy, is looking at the effects of ice buildup on the blades, and ways to counter it. (NSERC is Canada's Natural Sciences and Engineering Research Council.) For instance, one possible ice-control plan is to heat the leading edge of the blade, he said.

St. Leon is somewhere around the 50th parallel. The weather gets cold that far north in the wintertime, averaging about -18°C in January. The temperature in the university's wind tunnel can reach as low as -40°C, Bibeau said.

The tunnel has force balances—that is, the sensing equipment—from Allied Aerospace in San Diego and an MGCPlus data acquisition system from HBM Inc. in Marlborough, Mass.

According to Dennis Booth, manager for force measurement systems at Allied Aerospace, the company supplies force balances with the HBM equipment, unless a customer specifies otherwise. Allied Aerospace operates two wind tunnels of its own, where it has tested military aircraft, racecars, and even the aerodynamics of a Tour de France cyclist's helmet. It uses the HBM system there, and Booth said that, when custom equipment contains the same brand, it is easier to calibrate before it is shipped to the customer.

HBM's sales literature says that the MGCPlus is a modular system of user-configurable hardware using off-the-shelf components, allowing for expansion to as many as 10,000 channels.

Bibeau at the University of Manitoba said the DAQ system is simple to use. "It plugs into the computer," he said.

The portable laser tracker is picking up in popularity. It may not be on the scale of sliced bread or canned beer, but Ford, Boeing, and Northrop Grumman, for instance, have tried them and liked them well enough to order more.

The portable laser tracker is a coordinate measuring machine that can be set up where it is needed in a plant to verify the manufactured accuracy of surfaces, joining edges, and the like. It can also gather 3-D data to reverse-engineer legacy parts.

Ford Motor Co. plans to have the laser trackers in all its major North American assembly plants. The company owns more than two dozen of the machines made by Leica Geosystems, many of them bought within the past few months. It also owns 19 Leica T-Probes and 19 seats of software.

The T-Probe, its maker says, gets laser tracking into hard-to-reach surfaces.

Rina Molari, technical consultant and key accounts manager at Leica, said the laser tracker locates and follows the T-Probe as it is moved by hand across a surface. By calculating where the point of the probe is at each data point, the system can pick up very closely the shapes of parts of various sizes.

The spec sheet says the tracker has a measuring rate of 3,000 points a second. According to Leica, the system using the T-Probe has an accuracy within 100 micrometers at distances of 7 meters or less. The software, called Metrolog XG for Leica, processes data and can compare the measured results to the specifications of a CAD model to determine manufacturing accuracy.

Leica says the tapered stylus of the probe will reach details of surfaces that would be inaccessible to a spherical target usually used with laser trackers.

Ford will use the systems to verify the accuracy of tooling and of finished products, including fixtures and bodies in white. The company purchased model LTD700 machines, which have a range up to 25 meters.

Northrop Grumman received seven laser trackers from Leica in August and will use them at its factory in El Segundo, Calif., for quality assurance of the tooling and assemblies it will make there for the Joint Strike Fighter. They are model LTD800 machines, with a range up to 40 meters.

The company uses two older-model laser trackers from Leica for quality control in the manufacture of the Global Hawk unmanned aerial vehicle for the Air Force.

Faro Technologies Inc., meanwhile, reported that The Boeing Co. ordered 10 model Xi laser trackers in July for use in the rotorcraft plant near Philadelphia that produces the Chinook helicopter and the Osprey tiltrotor airplane. Faro said the system uses a spherical mirrored target and has a maximum measuring range of 230 feet, or about 70 meters. At shorter distances, its accuracy is a thousandth of an inch, about 25 micrometers. It can record up to 350 data points a second.

The Xi is Faro's more traditional machine. The company also offers a model X, which is less expensive because it contains no interferometer (and no "i" in its name). The interferometer calculates measurements based on the interference in light waves.

The model X, according to product manager Chuck Pfeffer, uses a phase shift calculation method that the company calls XtremeADM. The initials stand for "absolute distance measurement." It has a list price about $35,000 less than the model Xi.

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