The position sensor board uses the AS5147 is a 14-bit Magnetic Encoders

One for is used for the motor electrical position/angle. One is used for the joint position/angle. The are connected via daisy chain on SPI communication with 2x 16bit clocking. There is a piece of Silicon Steel between the two sensors boards to prevent cross flux of diametric magnets.

The technical information for the system:-

• 14500RPM (240 REV/sec) 
• Multistar Elite 5008 motor maximum speed 7000 RPM
• 7 Pole pairs
• 10kHz sample rate (85 samples per revolution at full RPM)
• 12 samples for electrical rotation at full RPM
• DAEC™ dynamic angle error compensation

This basically means that they are quite suitable for this application.

The Schematic and PCB has been uploaded to the "file page".