Modern multi-axis systems require high resolution and bandwidth within each motor controller as well very fast communication between master and slaves. MACCON and our partners have two approaches to realizing network topologies for such high-performance systems:
CENTRALIZED control - a powerful multi-axis controller (1-64 axes) is responsible for the command and coordination of all axes. This controller is also performs most of the individual axis control algorithms, leaving phase current or only power switching control at inverter level. Command transmission is either via a digital, analog, MACRO or EtherCAT interface, see Delta Tau.
DECENTRALIZED control - a light host coodinates multi-axis activities but all real-time motor and machine funcitons are are performed by individual and districbuted control modules, including motor control and I/O: EtherCAT ensures real-time data communication between the host and the slaves. Here are the characteristics of such a system:
- Standard Ethernet physical layer on master, dedicated hardware on slaves
- On-the-fly frame processing done by hardware -maximum performance
- Precise synchronisation with distributed clocks (<1µs jitter)
- Flexible topology - no routing equipment needed for line topologies
Our partner ACS has perfected this form of implementation of EtherCAT based muti-axis systems, ensuring the closest possible time coordination of actions in each axis of motion:
- One Machine Processor Unit (MPU) - executes high level tasks – communication,
- interface, programs, diagnostics, I/O control etc and profile generation.
- Few (slaved) servo processors (SPii) - execute real-time control algorithms at 20kHz.
- High sampling rate independent on number of axes
- Ease of Control customization and high throughpu
- One "SPii" node manages a few axes – the best synchronization
If beneficial, one motor controller can take over the command of all other axes, as well as its own motor.
Our other partners also offer EtherCAT based (IEC61131) motor controllers. which can be networked and controlled as one complete Motion Control system:
- MACCON SWM7/MACinverter
- Kollmorgen Servostar/AKD drives
- Copley Accelnet/Xenus PLUS
- Servotronix CD/HD drive
These controllers also support the CANbus, if preferred.