Sick Stegmann introduced SinCos® SEK52 servomotor feedback systems with HIPERFACE® interface.  The SEK52 features a simple design that eliminates components that tend to wear.
 

They were designed for use in applications that need high performance precision feedback in a compact package.

The SEK52 features integral scanning to automatically compensate for eccentricity errors common to standard motor feedback systems, and provides high-resolution performance with 512 steps per revolution, and 16 sine/cosine periods per revolution.  They are housed in a 14mm rugged metal housing that is resistant to dirt and moisture, as well as shock to 100 g (10 ms) and vibration to 20 g (10...2000 Hz).