ethercat as a master machine control tool' galil webinar
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Galil Motion Control
Matt KlintApplications EngineerGalil Motion Control
EtherCAT as a Master Machine Control Tool
Agenda
• Galil Motion Control
• About
• Introduction to EtherCAT
• Origins
• Communication Format
• Ethernet vs. EtherCAT
• Hardware and Physical Layout
• Galil’s DMC-500x0 EtherCAT Master
• Features
• Configuration and Setup
• Setup Example
• Summary
• Cost and advantages of an EtherCAT control network
• Q&A
About Galil
Established Reputation and long History of Success
• Founded in 1983 by Dr. Jacob Tal and Wayne Baron
• Introduced the 1st microprocessor based servo controller
• Profitable for over 110 consecutive quarters
• Over 750,000 motion controllers and PLCs delivered
Excellent Engineering Support and Service
• Worldwide network of factory trained reps & distributors
• Support team with over 100 years combined motion control experience
• Online support tools at www.galil.com
Communication Protocols
• Standardization allows cross platform integration
• Easily attainable infrastructure lowers costs
• Modular Design
• Modules are easily replaceable
• Additional modules can be added as needed
• Wide market with dozens of vendors per type
EtherCAT Origins
Ethernet for Control Automation Technology
• Invented by Beckhoff Automation in 2003• Ethernet based fieldbus, optimized for industrial automation control• Based on CANOpen, a device profile for embedded systems used in
automation• Standards defined and maintained by the EtherCAT Technology Group
(ECTG)
EtherCAT and Ethernet
• Ethernet• Designed to move large amounts of data through many different nodes
• Able to route data to and from billions of separate addresses allowing communication across vast networks
• Large overhead involved in encapsulating, routing and formatting data
• Software handles extraction and processing of data
• EtherCAT• Uses standard Ethernet hardware, CAT5 cabling and Network Interface Cards (NIC)
• Streamlines Ethernet communication at the hardware level
• Data processing on slave devices is handled “on the fly” via FPGA or ASIC, minimizing latency
• Initial setup and configuration required
Ethernet Frame
An Ethernet frame contains:
• Ethernet Header
• Destination Address: 6 bytes
• Source Address: 6 bytes
• EtherType: 2 bytes, 0x0800 specifies IPv4.
• Ethernet Data
• Payload: 46 – 1500 bytes
• CRC (Checksum): 4 bytes
Standard Ethernet Frame
EtherCAT Frame
An EtherCAT frame is very similar to an Ethernet frame:
• Ethernet Header
• EtherType 0x08A4 specifies EtherCAT
• EtherCAT Header
• Data Length: 11 bits
• Reserved: 1 bit
• Protocol type: 4 bits (0x01 indicates CoE, CAN over EtherCAT)
• EtherCAT data: 46 – 1496 bytes
• Working counter: 2 bytes
• CRC (Checksum): 4 bytes
EtherCAT Frame
EtherCAT Communication
• Each drive on the network has a unique address, set by hardware• Master/Slave configuration with the EtherCAT Master sending and
requesting data from the Slave• Data not addressed to a particular slave are forwarded along to the
network• Minimal processing time can provide cycle update rates of up to
32kHz• Network Layout size is limited only by the allowable lengths of CAT5
Ethernet cable, up to 100 m• Increased noise immunity due to reliance on Ethernet physical
components
Each cubicle is an EtherCAT Slave, each engineer is told where to sit by an SDO
The boss is the EtherCAT Master, sending instructions (PDOs) out to the engineers each morning and picking up their work at quitting time.
EtherCAT Communication Analogy
Object Dictionary: x6060
• Profile PositionMaster sends position commands to the Slave, slave handles profiling parameters
• Profile VelocityMaster sends velocity commands to the Slave, slave handles profiling parameters
• Profile TorqueMaster sends torque commands to the Slave, slave handles profiling parameters
• Cyclic PositionPosition is continuously updated by the master, master handles profiling parameters
• Cyclic VelocitySpeed is continuously updated by the master, master handles profiling parameters
• Cyclic TorqueTorque is continuously updated by the master, master handles profiling parameters
EtherCAT Operation Modes
Master
• Can be any software and or hardware configured to assemble, send and receive EtherCAT datagrams
• Requires only standard Ethernet physical layer components for communication
• Facilitates coordination between EtherCAT slaves, writing and receiving data from each slave in an EtherCAT frame
• In motion control applications, the relevant data sent to the drives are profiling data
• The data requested are position and input status
EtherCAT Master
• Slave
• Reads and processes profiling data
• Writes position, input and drive status for return to the master
• Can be configured in for multiple modes of operation
• All slaves contain specific spaces in memory where data can be written
• These spaces are called Objects, the entire memory space is called the Object Dictionary
• Each object has it’s own address, specified as an index/sub index
• Example, operation mode data from the Master is written to the x6060 Object in the slave’s dictionary
EtherCAT Slave
SDOs and PDOs
Data is moved along an EtherCAT network using two protocols, SDOs and PDOs
SDO: Service Data Object
• SDOs can be sent at any time, before, after or during real time operation of
the network but require additional communication overhead
• As a result SDO usage is typically only used for network setup commands
PDO: Process Data Object
• PDOs contain the raw operational data with minimal overhead and thus are
used for real time processes, like motion and I/O control
• PDO’s can only be used once they are “mapped” using SDOs
• Mapping sets up which byte in each PDO goes to which memory address on
the slave
SDO vs. PDO Summary
SDO PDO
Transfer confirmation No transfer confirmation
Client/server model Peer-to-peer model
Device Configuration, PDO mapping High priority transfer of small amounts of data
Can be sent at any time Can only be used after configuration usingSDOs
Significant communication overhead No additional protocol overhead
The EtherCAT Slave State Machine
State Allowed Communication
Init No User Communication
Pre-Op SDO Communication Only
Safe-Op SDO, PDO Communication AllowedOutput PDO info ignored
Operational PDO, SDO Communication Allowed
The EtherCAT Slave Architecture
PDO Processing
Incoming PDOPosition Data
Slave Target Position Memory Object
4 x 8 bits
x607A
Master/Slave Communication
EtherCAT Communication Timing
EtherCAT Master EtherCAT SlaveCAT5 Ethernet Cable
t = 0
t = 1 ms
EtherCAT Hardware
Standard Ethernet Physical Layer components• CAT5 cabling
• Network Interface Cards
FPGAs for fast command processing by
slave units
EtherCAT Only Physical Layout
EtherCAT Master
EtherCAT Drive 1
EtherCAT Drive 2
EtherCAT Drive 3
Motor/Encoder
Motor/Encoder
Motor/Encoder
The DMC-500x0 EtherCAT Master
• Includes all the features of our flagship DMC-40x0 series controller with the addition of EtherCAT drive support for up to 8 axes in Cyclic Position Mode*
• Only motion controller in the industry with the ability to mix and match local and EtherCAT drives
• Easily configurable and designed with compatibility and flexibility in mind
• Multiple drive vendors supported
• Compatible with Galil’s entire line of internal servo and stepper motor amplifiers
*Cyclic Torque mode supported on select models
The DMC-500x0 EtherCAT Master
Currently Supported I/O Features• Forward and reverse limit switch inputs• Home sensor input• Hardware latch/touch probe
These I/O features allow access to the DMC-500x0 commands and subroutines specific to these inputs such as:
• #LIMSWI automatic subroutine• FI/FE/HM commands• AL/RL commands• #ECATERR automatic subroutine
DMC-500x0 Hardware Layout
DMC-50070
EtherCAT Drive 1
EtherCAT Drive 2
EtherCAT Drive 3
Servo Motor
Servo Motor
Servo Motor
Analog and
Digital I/O
Stepper Motor
Servo Motor
Servo Motor
Stepper Motor
StepperDriver
StepperDriver
Compatible EtherCAT Drives
Currently Supported Drives
• AMC DZEANTU-020B080
• Copley XenusPLUS XEL-230-36
• Panasonic Minas A5B
• Sanyo-Denki SANMOTION RS2A01A0KA4
• Yaskawa Sigma-5 SGDV-R90FE1A
Galil is actively working to include support for additional vendors and is seeking input
from customers. Contact an Applications Engineer to discuss drive support options.
Summary
• The EtherCAT protocol is gaining traction as a robust and efficient solution to
demanding, large scale automation applications
• Built on the Physical and Data Link layers of Ethernet communication, making the
technology more accessible right off the bat
• Higher controller/drive cost is offset by the use of pre existing, easily attainable
hardware
• Due to the EtherCAT communication protocol, networks are easily expandable,
modifiable and simple to maintain
Please submit your questions regarding any part of this presentation or about
EtherCAT in general at this time
Additionally, please contact Galil’s dedicated Applications Engineering team anytime
with additional questions or comments:
Q & A
1 800 377 6329support@galil.com
In Canada contact:Electromate1 877 737 8698sales@electromate.com
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