Test & Measurement

Dyno Torque Measurement

Conventional reference torque transducers can deliver excellent standalone accuracy, but their integration into a dynamometer or drivetrain test rig adds couplings, bolted joints, inertia and compliance. At high speed or during rapid transients, these factors can contribute to alignment challenges, torsional vibration and a difference between a sensor’s static specification and its performance within the complete test system.

Transense SAW technology allows the load-carrying shaft itself to become the torque sensor. Surface Acoustic Wave sensing elements are bonded directly to the shaft, with torque measured wirelessly and without the need for a conventional in-line transducer. This can reduce the number of mechanical interfaces, shorten the drivetrain and simplify the overall test arrangement. With highly customisable designs based on semi-standard designs Transense provides you the ability to customise your test system to suit your needs, rather than building a test system around a fixed sensor.

In an example high-speed (>20k rpm) transient test application, replacing a market leading reference transducer with a SAW-instrumented shaft improved the test setup, eliminated problematic torsional vibration and delivered higher-resolution data with lower measurement delay. The result was a cleaner mechanical system and more useful insight into fast-changing torque events.

Key benefits include:

• Direct torque measurement from the shaft connecting the load to the device under test
• Reduced couplings, joints, inertia and compliance in the driveline
• Lower risk of test-rig-induced torsional vibration
• High dynamic response for transient measurements
• High-resolution data with low measurement delay
• Wireless sensing without slip rings or shaft-mounted batteries
• Greater freedom to optimise the shaft and test-system architecture

Real World Torque Measurement

Laboratory reference transducers are not suitable for installation within the complete mechanical system or for operation in real-world test environments. Transense SAW technology can turn an existing load-carrying component into a torque sensor, allowing the measurement system to be embedded directly into drivelines, transmissions, motors and engines without the packaging constraints of a conventional in-line reference transducer.

This enables engineers to capture high-resolution torque data during vehicle, machine or system-level testing, under the loads, speeds, temperatures and transient conditions experienced in service. The resulting measurements provide direct insight into component behaviour, efficiency, durability and system interactions that may be difficult to reproduce or observe on a laboratory test rig alone.

Compared with strain-gauge telemetry systems, passive SAW sensing requires no shaft-mounted power supply or rotating electronics, helping to reduce packaging complexity and remove battery-life limitations. Its compact, robust architecture is well suited to long-duration testing in harsh environments and integration into space-constrained mechanical systems such as such as inside transmissions and powertrain systems.

Temperature Measurement

Temperature is often most valuable—and most difficult to measure—on rotating components. In high-performance electric machines, for example, rotor temperature directly affects magnetic performance, efficiency, durability and the amount of power that can be used safely. Thermal models can support development, but they may not capture fast transients, local hot spots or the full range of real-world operating conditions.

Transense SAW temperature sensing provides a passive, wireless measurement directly from the rotating component. This gives engineers measured data with which to validate thermal models, optimise cooling strategies and understand the true operating margin of the system.

Direct rotor-temperature data can help developers reduce conservative safety factors, improve power density and assess alternative motor architectures or magnet materials. The same principle applies across test and measurement applications involving rotating shafts, motors, gearboxes and other components where wired sensors are difficult to package or may influence the system being measured.