Nothing exemplifies Novotechnik’s leadership in touchless, magnetostrictive, and potentiometric position sensing better than the introduction of new technologies and new products that provide the added functionality needed to support new applications.
For example, Novotechnik recently introduced the first encoder (also referred to as a rotation counter) to be based on its patented RSM – Rotation counting Sensor Magnetoresistive – technology. RSM eliminates the need for the gears or external power supply found in conventional rotation encoders resulting in a very compact multiturn sensor that can be easily integrated into a wide variety of applications.
Novotechnik’s RSM technology takes advantage of magnetoresistance, a phenomenon in quantum mechanics, to provide an economical and highly-accurate solution for customers needing to measure absolute angles over several turns.
The phenomenon occurs in thin film structures when two ferromagnetic layers are separated by a thin non-magnetic film. When the two magnetic layers are parallel, resistance drops to a minimal value. As the magnetic layers are turned so they are no longer in parallel alignment, electrical resistance increases.
This increase can be used to measure absolute position values. Novotechnik RSM sensors retain their full turn and angle information even after long-term power loss and provide these measured values immediately following start-up. Since these are non-contacting sensors, they are virtually wear-free and can be easily integrated into a wide variety of applications without the need to create mechanical linkages.
While magnetoresistance is now being used in CD, DVD and computer hard disk drives, Novotechnik is the first company to adapt the technology for position sensors.
Novotechnik solved the problem of measuring absolute angles over several turns by offsetting two multi-turn elements by 90° merging the two structures in a diamond pattern. With this structure, a clear rotation value can be derived in any angular position using a corresponding evaluation algorithm.
Utilizing RSM technology, Novotechnik is building sensors that can count and permanently store up to 16 rotations and supply absolute position values over 360° without mechanical gearing or a buffer.
These new sensors complement Novotechnik’s extensive family of contact and non-contact, rotary and linear sensors that extends from miniature rotary sensors measuring as little as 13 mm for use in medical devices to rugged linear position sensors designed for hydraulic, pneumatic and other extreme operating environments.