After a 5 year break from Drives & Systems, I’ve returned!
I’ve stayed active in the industrial automation space and worked through a range of machine automation projects at Schneider Electric over the last few years. From robotics and motion through HVAC and pump control systems. Lots learnt and and a lot to capture. Hopefully capturing some of it here comes as a benefit to others.
Wasn’t sure what I was going to find here but I have come back to some interesting stats on the site. Also some good insight around PLC programming topics users engaged with most here. For instance users seem to have landed here while googling for info on Codesys arrays. This is a promising development in the industrial controls world, knowing that data structures are being used more at the PLC level. Will expand on some of this insight and the topic of arrays in PLC programming in a future post.
For today, I’ve been exploring the usage of ChatGPT in industrial automation. The combination of large language model processing and reinforcement learning along with what seems to be a substantial data set has led to a pretty amazing outcome. More importantly, it will have some strong use cases in industrial automation too. The use cases from code generation to building specifications, data collection to troubleshooting will likely unfold more and more in the coming months and years.
A query I took to ChatGPT recently was to compare a few different real time Ethernet communication protocols. While some of this may be outdated since the data references are from September 2021, the output generated was quick and definitely a great reference for automation industry folks.
Whether working through a specification or just looking to learn about the different protocols, this will come in handy.
One important point, the quality of the query makes all the difference. For example when I queried a comparison with Sercos, the outcome was totally different from Sercos III which is newer. So be precise on the query.
|
Network |
EtherCAT |
SERCOS III |
Ethernet/IP with CIP motion |
|
Architecture |
Centralized controller to multiple devices |
Centralized controller to multiple devices |
Distributed control system (devices communicate directly) |
|
Topology |
Line, Tree, Star |
Line or ring network |
Star, Linear, Ring |
|
Data Transmission |
Asynchronous |
Asynchronous |
Synchronous |
|
Data Transfer Rate |
Up to 10 Gbps |
Up to 100 Mbps |
Up to 100 Mbps |
|
Cycle Time |
100 ns |
31.25 μs |
Up to 16 μs |
|
Determinism |
Highly deterministic | Highly deterministic | Moderately deterministic |
|
Jitter |
Very low |
Low |
High |
|
Synchronization |
Hardware-based |
Hardware-based |
Software-based |
|
Scalability |
Good |
Limited |
Good |
|
Real-time Communication |
Yes |
Yes |
Yes |
|
Security |
Good |
Good |
Good |
Descriptions of each area of comparison:
| Row | Description |
|---|---|
| Architecture | The relationship between the central controller and the network devices, including whether the network is centralized or distributed, and whether devices communicate directly with each other or through the central controller. |
| Topology | The physical layout of the network, including whether it is a line, ring, or star network, and how devices are connected to the network. |
| Data Transmission | The method used to transmit data on the network, including whether it is synchronous or asynchronous. |
| Data Transfer Rate | The maximum rate at which data can be transferred on the network, typically measured in bits per second (bps) or megabits per second (Mbps). |
| Cycle Time | The time it takes for one complete cycle of communication on the network, including the time it takes for the central controller to send a command to a device and receive a response. |
| Determinism | The degree of consistency in the time it takes for communication to occur on the network, with high determinism indicating a consistent and predictable communication pattern. |
| Jitter | The amount of variation in the time it takes for communication to occur on the network, with low jitter indicating a consistent and predictable communication pattern. |
| Synchronization | The method used to synchronize communication between devices on the network, including whether it is hardware-based or software-based. |
| Scalability | The ability of the network to accommodate a varying number of devices without significantly impacting its performance or requiring major changes to the network architecture. |
| Real-time Communication | The ability of the network to support real-time communication, which is critical for industrial automation applications where precise timing is necessary. |
| Security | The level of security provided by the network, including measures to prevent unauthorized access, data loss, or data corruption. |
References:
- EtherCAT: “EtherCAT Technology Group – Basics of EtherCAT” https://www.ethercat.org/en/basics.html
- SERCOS III: “SERCOS International – SERCOS III Overview” https://www.sercos.org/technology-overview/sercos-iii/
- Ethernet/IP with CIP motion: “ODVA – EtherNet/IP Overview” https://www.odva.org/Technology-Standards/EtherNet-IP/Overview-of-EtherNet-IP/
