ServoWire is ... fast

ServoWire Network operates at 200 megabits per second --- 8 servos update at 2kHz; 4 servos update at 4 kHz

ServoWire^® is fast … delivering servo performance with digitally networked drives that is comparable to analog torque mode drives.

Servo loop updates are based on the number of drives on ServoWire network (2kHz for 8 axes; 4kHz for 4 axes) as well as software features enabled. IEEE-1394 provides fundamental technology which guarantees real-time network determinism and provides extra bandwidth for communication transfers.

With the drive network operating at 200 megabits per second, there is plenty of bandwidth for the servo update rates required in high performance systems. Bandwidth alone, however, doesn’t define fast. The blending of "isochronous and asynchronous" communications is the feature of IEEE-1394 that most uniquely qualifies it as a multimedia and servo network. A Sercos drive network has a similar dual approach to communications, which they call "cyclical and non-cyclical". This method, without the bandwidth to back it up, doesn’t meet high performance servo application needs.

With ServoWire^® isochronous communications occur at regular intervals up to 8 kilohertz, allowing the transfer of time critical information every 125 microseconds. This capability meets the needs of even the highest performance servo systems. In addition, the pure horsepower of IEEE-1394 provides the ability to transmit a generous amount of other information such as tightly coupled I/O (PLSs, registration sensors, etc.) which must be coordinated with the servo control in many applications.

Since 1394 has a defined bandwidth roadmap to much higher data rates, ServoWire^® will be able to address larger numbers of axes and include even more control elegance in the future.