Powertrain

Case Study

Researchers were testing and evaluating a 2004 hybrid automobile using Teledyne LeCroy’s Engine Torque Measurement System. They were mapping the vehicle’s major components and exploring the advanced controls used to achieve high fuel efficiency in its Hybrid Synergy Drive, but found that acquiring clean, accurate data in the hybrid electric vehicles’ high-voltage, electromagnetic interference-filled (EMI) environment posed a significant challenge.

An in-situ torque sensor was installed between the engine and the electric drivetrain, but the off-the-shelf torque-sensing element had temperature limitations (requiring external cooling), was susceptible to damage from torque spikes, and required an additional 3” of powertrain length to accommodate the sensor. A custom spacer between the engine and transmission was also required, as well as modification of the vehicle frame rail. These modifications limited the vehicle to off-road or dynamometer operation.

Teledyne LeCroy provided a newly developed zero-clearance torque sensor, which provided a much more elegant and robust solution. With this new design, no vehicle modifications were required, saving almost $20k in custom brackets and vehicle work, and allowed the vehicle to be driven normally on public roads.

The Teledyne LeCroy Solution

Many disciplines within the automotive community have a need to measure in-vehicle driveline torque during testing. These include engineers testing transmissions, engines, clutches, differentials, ABS and traction control systems, tires, suspension components, and active suspension systems. Efforts to reduce emissions and improve vehicle efficiency also require accurate and non-intrusive techniques of measuring torque and horsepower. Typical powertrain torrque measurement applications include development and verification of engine torque algorithm; measuring engine torque during shift cycles; development of traction control and ABS systems; measuring torsional dynamics/resonance; efficiency testing; and engine and transmission trouble shooting.

While many companies produce off-the-shelf rotating and reaction torque sensors, Teleddyne LeCroy excels at providing custom solutions for unique customer applications that are not often addressed by commercially available alternatives. We have extensive expertise in torque measurement, utilizing and applying strain gauges to rotating equipment and delivering high-frequency data using robust noncontact, wireless telemetry technology.