IO Link Device Timestamping for Event Timing Precision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing automation systems lack a precise method to determine the timing of events detected by IO devices, such as sensors and actuators, without local clocks, which is essential for error-free process control and monitoring.
Innovation Solution
A communication system where IO devices are connected through an IO link system with a star topology, utilizing a synchronized clock device to assign precise time stamps to measurement or action events, and incorporating a time correction value to account for internal delays during data transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If IO devices do not include local clocks to reduce device complexity and cost, then the device complexity and cost are reduced, but the ability to precisely determine event timing is lost
Solution Approach 1:
The patent introduces an intermediary clock device connected to the IO link that serves as a time reference for all IO devices. This central clock acts as a mediator, providing time stamps to multiple IO devices without requiring each device to have its own clock, thus resolving the contradiction between reduced device complexity and maintained timing precision.
Solution Approach 2:
The patent replaces the mechanical approach of having physical clocks in each IO device with a centralized time stamping mechanism. Instead of each device maintaining its own timekeeping mechanism, the system uses a central clock that inserts time stamps into data frames, substituting distributed mechanical clocks with a centralized time reference system.
2Device complexity
If time data and status data are transmitted separately to reduce data transmission complexity, then the data transmission structure is simplified, but the synchronization between time stamps and events is lost
Solution Approach 1:
The patent merges time data and status data into the same transmission channel by inserting time stamps directly into data frames that contain status information. This combining approach ensures that time information and event information are transmitted together, maintaining their synchronization relationship while using a unified transmission structure.
Solution Approach 2:
The patent applies preliminary action by pre-calculating and inserting time stamps into data frames before transmission. The clock device determines the current time and embeds it into the data frame structure in advance, ensuring that time synchronization is established before the actual data transmission occurs, thereby maintaining reliability.
Data Source
AI summary
A method and communication system that provide an inexpensive approach that enables the times of events that are detected in IO device to be determined in a higher-level controller. The higher-level controller has a system clock and is connected to an IO link device to which multiple first IO devices are able to be connected. In addition, a second IO device is connected to the IO link device. The clock of the second IO device is synchronized by a synchronization device with the system clock of the higher-level controller. The status data that are provided by at least one of the first IO devices and the current time data that the second IO device supplies are transmitted simultaneously to the IO link device. The IO link device assigns the status data received to the received current time data, then transmits these data to the higher-level controller.