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NVH data collection

Point-and-click order extraction is possible via the Roush Gabor Order Tracking Analyzer.

Unique tools for conducting automotive NVH measurement and testing provide engineers with real-time data collection and analysis methods. The recently updated BrakeDAQ version 5.0, a second-generation in-vehicle system for brake noise detection and analysis, employs the graphical programming language LabVIEW from National Instruments. (When BrakeDAQ was introduced in 1996, the product used a text-based code.)

"LabVIEW makes it very easy for us to customize the interfaces for our customers," said Michael Albright, Manager of Advanced Projects for the Roush Anatrol Division, the NVH engineering and product development arm of Livonia, MI-headquartered Roush Industries, Inc.

All electronic hardware (i.e., the portable PC-based PXI platform for data acquisition and control applications) for BrakeDAQ is provided by National Instruments; Roush Anatrol provides the connectivity for customized problem solving. "BrakeDAQ essentially counts brake noise events and quantifies those events in terms of temperatures, frequencies, and amplitudes while putting objective and subjective ratings on each noise event," said Albright.

The standard BrakeDAQ system includes an embedded PC, two 16-bit 333 kilo-samples per second data-acquisition devices, expandable modular signal-conditioning circuitry, one microphone, four accelerometers, two pressure sensors, four temperature sensors, and a humidity sensor.

"This system can record up to 28 miscellaneous voltages and up to 28 different temperatures. BrakeDAQ can log all that information at a rate up to 100 Hz during a stop event," said Albright. "The relevance of that is it allows us to eventually extend the system's capability to other brake testing, like brake performance testing."

BrakeDAQ runs on National Instruments' PXI system, which has been adapted by Roush Anatrol to meet demanding in-vehicle test requirements.

BrakeDAQ provides two-tier recording capability. The system logs information 10 times a second as well as captures specific braking event information.

In early 2002, Roush Industries expects to commercially release its Gabor-based Order Tracking Analyzer. "It's a brand new method for extracting order domain information from any sensor on any machine with rotating elements where the conditions are changing with time," said Albright.

National Instruments contributed its LabVIEW software development environment as well as certain software algorithms and data-acquisition hardware. Roush wrote the application-specific software used on the LabVIEW platform. "The software on this system permits the isolation of signal components proportional to the revolution speed of the shaft," said Albright.

"You can look at events occurring at eight times the revolution of a shaft, then go back and look at events at four or six times the revolution of a shaft at will," said Pete Zogas, Vice President of Sales for National Instruments in Austin, TX.

Performing order analysis via this technique is unique. "Nobody else can do the Inverse Short Time Fourier Transform, which means you can go back and forth between time domain and frequency domain," said Albright. The conventional method of tracking is either frequency or time domain methods.

Another unique aspect of the analyzer is the lack of time needed to complete a task. "It's literally point-and-click order tracking in the blink of an eye," Albright said.

- Kami Buchholz

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McLaren's high-octane enterprise

A worker tweaks a computer-generated image at McLaren's design center.

A company that provides full-service design, development, fabrication, manufacturing, testing, validation, and certification of automotive powertrains and related components as well as development and licensing of patented traction systems has turned the headlights on its complete vehicle development and prototyping capabilities.

"The pillar that we're built on is engineering services, and we're trying to broaden that a bit," said Steven Rossi, President and CEO of Livonia, MI-headquartered McLaren Performance Technologies. "We've been very good at designing, developing, validating, testing, and certifying." The company's past achievements have focused on specific tasks or have ended with another company doing production, "but for the first time we have postured ourselves to go truly from prototype to production," he said. (The McLaren portfolio includes past specialty vehicles like the Buick GNX and the Pontiac GTP Turbo.)

Engine machining at McLaren.

McLaren's prototype-to-production capability will be exemplified with the release of a new vehicle. "We're partnering in a conceptual stage, but how the (vehicle) ends up ultimately remains to be seen," Rossi said, referencing a niche vehicle (possibly a high-performance pickup truck, an upscale luxury sedan, or a front-wheel-drive youth-market car). The vehicle's first reveal is anticipated sometime in 2001/02.

The new business model also emphasizes the automotive aftermarket via McLaren Performance packages (as in a systems' supplier), as well as a product licensee. To help reach that goal, McLaren Performance Technologies acquired Oldcastle, Ontario, Canada-based Dart Machine Ltd. in the spring of 2001. The renamed McLaren Performance Products manufactures precision powertrain components such as cast-iron and aluminum cylinder heads, engine blocks, and differential housings.

Workers conduct engine testing at McLaren.

"We're engineering our growth plans on the strategy of controlling our own destiny," said Rossi. "We work for everybody in town, and we have very good relationships. But if we build our growth plans solely on a specific alliance with a specific manufacturer, we're not going to be able to move necessarily where we want to move because we're too far down the food chain."

McLaren's Livonia facility includes 16 hydraulic and eddy-current dynamometers that range up to 753 kW (1010 hp) from 2000 to 14,000 rpm as well as subsystem testing, including coolant flow analysis, circulation rate, pressure gradient, water pump power/efficiency evaluation, thermal shock testing, lubrication, and aeration evaluation. Exhaust emissions evaluation, air/fuel ratio analysis, airflow studies, heat rejection testing, and knock/pre-ignition monitoring also represent the testing capabilities conducted on a 24/7 basis.

"First and foremost we are an engineering services company," Rossi said. "We're just trying to create a little more balance, to put a couple more revenue streams in place. But everything we do ultimately feeds back to our services."

- Kami Buchholz

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