Contactless torque measurement

Torque measurement technology for rotating shafts under real operating conditions

In modern powertrains, torque is the primary reference variable. It directly reflects the load acting on gearboxes, shafts and joints. AXON measures it contactlessly – directly on the rotating shaft, robust against oil, temperature, vibration and electromagnetic interference.

Discuss torque measurement Download whitepaper

resolution: 16-bit
power & data: contactless
or analog: CAN
in operation: maintenance-free

Drive shaft with AXON telemetry for contactless torque measurement

Contactless power and data transfer

16-bit digitization directly on the shaft

Rotor temperature and supply status as operating data

CAN integration for vehicle and test-bench environments

Challenge

Capture torque directly on the rotating shaft

Engineers in vehicle development and on test benches need to measure torque on drive shafts, gearboxes and electric motors with high precision and reproducibility. Conventional slip-ring systems reach their limits in rotational speed, maintenance, installation space and wear.

On top of that, real environments add their own constraints: oil, temperature, humidity, contamination, plus combined mechanical, thermal and electromagnetic loads at the measurement location.

× Limited installation space in the drivetrain
× Oil, water, temperature, contamination
× High rotational speeds and continuous duty
× Electromagnetic interference

AXON approach

Telemetry on the shaft instead of slip rings

AXON uses contactless telemetry: power is transferred inductively and wear-free, measurement data is digitized on the rotating structure and transmitted with high noise immunity.

The build is compact and adaptable, with minimal impact on the dynamic behavior of the drivetrain. Operating parameters such as supply status and rotor temperature are transmitted alongside the measurement data for continuous quality assessment.

Strain gauges directly on the shaft
Inductive, wear-free power supply
Digital, interference-resistant data transfer
Operating data in real time

Application proof

What a reliable measurement solution really stands on

Validation

Real load spectra instead of model assumptions

Torque captures load changes and peaks directly. Shaft-side measurement provides reliable data for durability, fatigue strength and the design of modern powertrain systems.

Efficiency

Realistic evaluation in electric drives

In electric mobility, drive shaft torque measurements are key to drivetrain efficiency – including transient operating conditions and recuperation phases.

Measurement chain

On-shaft digitization as the foundation

Strain gauge signals are digitized directly on the shaft. Inductive power transfer and digital RF transmission improve signal stability and reduce interference.

„In modern powertrains, torque is increasingly regarded as the primary reference variable: it directly reflects the load acting on gearboxes, shafts and joints."

AXON whitepaper – Torque Measurement on Driveshafts

Why measure torque directly on the shaft?

In modern powertrains, torque directly reflects the load acting on gearboxes, shafts and joints. For durability, validation and efficiency analysis, indirect measurements are often not enough.

The measurement is taken directly on the rotating shaft without mechanical intervention in the drivetrain structure. This creates reproducible torque data for validation, efficiency analysis and durability testing under real operating conditions.

Contactless telemetry instead of slip rings

Slip rings reach limits in speed, maintenance, installation space and environmental robustness. AXON uses inductive, wear-free power transfer and digital signal processing directly on the rotor.

A strain gauge captures shaft torsion. The rotor unit digitizes the signal, transmits measurement data and operating parameters contactlessly to the control unit, and provides analog or CAN-bus output.