The ATi 2100 Series Digital Wireless Dynamic Torque Sensing Systems are utilized in applications where conventional wireless rotary torque transducers cannot provide the fidelity required for accurate gear mesh measurements. Gear mesh levels are typically less than 1% of the static torque levels, which results in the gear mesh signature being lost in the noise floor of conventional sensors.

ATi’s Dual Range Dynamic Torque Sensing Solutions provide two independent channels. The full range static channel is available for most any torque level, with 1000 to 6000 Nm being typical. The dynamic channel can be ranged for much lower levels, with 25 to 100 Nm being typical. This channel is AC coupled, so it remains active at high static torque levels.

RF Telemetry with noise free error checking is used for digital data transfer while Induction Power is used for power transfer to the rotating sensor. These technologies permit excessive movement of +/-4mm or more between the rotating sensor and stationary loop antenna with no ill effect on the signal quality – therefore minimal alignment between the stationary and rotating components is required.
Acquiring good gear mesh torsional data and other important NVH data is elusive with conventional torque sensors due to the limited dynamic range of the sensors. In the example on the previous page, a typical 5000 Nm torque sensing system would have a noise floor of about 20 Nm (peak to peak). Gear mesh data is usually less than 20 Nm for a typical ICE related axle or drive module. The NVH data is thus lost in the noise floor of the sensor. Some manufacturers provide an AC output, which is simply an AC-coupled and amplified version of the original signal. The noise floor of these sensors does not change at 20 Nm.

Dual Range Dynamic Option: ATi sensors have two fully independent strain bridges and torque channels. The first channel is full range and DC-coupled. Our noise floor is better than most sensors at 0.1% of full scale, or 6 Nm in this example of a 5000 Nm torque sensor. The second channel is AC-coupled (high pass filtered) and ranged much lower with its own dedicated signal conditioning. The dynamic channel can be ranged to 1% of the primary channel or 50 Nm in this example. The noise floor of this channel is 0.12% of full scale or 0.1 Nm. This is why so many manufacturers have standardized on ATi Dynamic Sensors for end of Line NVH testing. Our sensors also provide an update rate of 77,000 samples/second with up to 19 kHz of bandwidth for precise measurement of electric motor and gear reducer phenomena in EV component testing.

This option provides two full scale ranges and permits the user to select a second range (dynamic) which can be as low as 1% of the higher range. The dynamic output provides great detail on phenomena such as gear mesh torsional data and other low level torque phenomena. The dynamic channel is updated at 77,000 samples/second and provides 5Hz to 19kHz of bandwidth.
Excellent for End of Line NVH Testing. The dynamic output is AC-coupled, so components can be tested at higher loads, while examining minute dynamic torque fluctuations that produce gear whine and other unwanted noise and vibration. For example, the sensor can be measuring a static torque level of 3500 Nm during an end of line axle test, while the dynamic output ignores the static component of torque, and provides better than 0.025Nm of resolution.

Immune to the Environment. Digital RF Telemetry and Induction Power are also immune to dust and oil build-up. The sensors are very rugged and provide a minimum of 5:1 safe overload capacity (based upon the full range channel). ±6mm of sensor run-out in either the axial or radial direction can be tolerated, unlike most inductively-coupled sensors, which require accurate positioning.
Torsional Acceleration Monitoring Systems are also available from ATi for NVH measurements. Both torsional and radial acceleration channels are available with bandwidth up to 19 kHz.