About the technology
All electrical strain gauge based sensors and signal cables have the inherent property of acting as antennas, when passing through electromagnetic (EM) fields. Industrial and harsh environments are full of components that generate EM noise, such as transformers, electric motors, power transistors and others. These introduce noise in strain-gauge based torque signals.
Since optical (light) based sensors are immune to EM noise, the advantage is apparent in these types of environments. These embedded sensors are also very small, which means they can be placed in close proximity of EM noise generating components without any adverse effects. There is no signal integrity loss, distortion, or superimposed noise to worry about, and the sensor is able to maintain high measurement accuracy. The signal conditioning electronics can be placed up to hundreds of meters away from the measurement point, with optical cable runs in between, virtually eliminating the issue of electrical noise in torque measurement.
The optical torque sensor exhibits a high degree of linearity across a very wide torque range. The patent-pending sensor design minimizes operating temperature effects thus providing extremely good environmental compatibility. A key property of optical torque sensing which proves to be an advantage over traditional strain-gauge based products is the high frequency response of light-based systems. In essence, this eliminates the need for heavy filtering of the measured signal, allowing the data to be sampled at much higher frequencies. Torque-related mechanical events which happen in extremely short periods of time can be measured accurately without signature distortion.