At Sensors Expo 2019, Dennis Horwicz, Product Manager at Micronor explains how his company’s fiber optic sensors for mechanical motion applications can be used in challenging applications that include electromagnetic interference (EMI)/ radio frequency interference (RFI), radiation, high voltage, magnetic field, temperature extremes and even an explosive atmosphere.

A fiber optic kinetic sensor to measure temperature (TS) are true absolute temperature sensors consisting of a gallium arsenide (GaAs) crystal that is mounted on the end of an optical fiber. GaAs behaves like a temperature sensitive cut-off filter in which the crystal absorbs some light and reflect other light. The transition wavelength, between the reflected and transmitted spectrum is directly related to the absolute temperature. Operating over -200°C to +300°C (-328°F to +572°F), the fiber optic temperature probes can withstand harsh and corrosive environments.

Fiber optic incremental rotary and linear encoders are used in robotics application, motor control and motion control applications monitoring position, speed or velocity. The plastic optical fiber sensor in the demo enables the display of the absolute angular position. The plastic optical fiber is used to illuminate a code disc and an imaging fiber lifts the image and it is run through a high-speed camera in the controller that evaluates the barcode to generate the angular position.

For example, the MR430 Fiber Optic Position Sensor measures absolute angular position from 0° to 360° with 13-bit resolution and multiturn tracking up to 12-bits (4096 turns). The system can operate at full accuracy at speeds up to 2200 rpm and distances up to 30 meters.