CambridgeIC's resonant inductive position sensing offers designers a new way of embedding position feedback inside their products.
Traditional position sensors like optical encoders and hall encoder chips require precise alignment between parts. This is typically achieved by using a sensor that is already inside a precision housed assembly, and adding a precision coupling. Or perhaps by interating sensor components like a rotating magnet or code wheel, and taking special steps to achieve the precise alignment needed.
CambridgeIC's inductive sensors built from PCBs detect targets in the direction of motion, and are largely immune to off-axis movement and vibration. This allows designers to eliminate the bearings, seals, housings and couplings associated with traditional position sensors.
Linear, rotary and arc configurations can be tailored to the application by selecting from a wide range of sensor sizes and formats, rather than the application being constrained by the sensor technology. For example precision through hole rotary sensors allow a shaft to pass through the middle, and arc sensors measure angle from the side.
Motors are often fitted with multi-turn encoders, and drive loads thorugh a gearbox or other transmission system. The multi-turn encoder's output attempts to reflect the position of the load, but in fact it fails to detect backlash and other imprerfections in the drive system. Measuring the position of the final point of load is usually the objective. CambridgeIC's linear and rotary senosrs deliver high precision and an absolute output, and are often positioned a the point of load. This allows the specificaiton of the transmission system to be relaxed. Backlash in the transmission does not matter so much, because a position control loop is closed by a sensor at the point of load.
Optical encoders are often only incremental, or incremental with a refernece pulse, because absolute optical encoders are so expensive. Incremental senosrs delivering an A/B/N pulse train require an electronic register to keep track of position, and a homing step to recover absolute position at power on. CambridgeIC's CTU chips simply deliver absolute position measurements to a host on request, for example over a convenient and simple SPI interface. A single CTU processor chip can perform multi axis sensing, for example both the pan and tilt rotary axes in a surveillance camera, and multiple chips can share the same SPI bus.
Calculating velocity from an optical encoder is awkward, because it does not deliver useful information between pulses. Applications requiring reliable velocity information and high dynamic range usually have to opt for even more expensive encoders with high pulse counts. Calculating velocity is much easier when the sensor is absolute and can provide regularly timed position updates at high resolution.
Mechanical, electronic, systems, control and software design can all be simplified using resonant inductive technology from CambridgeIC. We offer solutions for innovators!