Bucket Brigade Data Transmission for Distributed Control Systems
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing field bus systems for automated control systems are complex, expensive, and inefficient for small data transmission, requiring special protocol chips and suffering from collisions and line faults that can disable the entire system.
Innovation Solution
A method using a series of connected stations with a 'bucket brigade' data transmission approach, where each station sends and receives individual data telegrams in a serial manner, avoiding collisions and allowing for efficient, cost-effective communication with low configuration complexity and fault tolerance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a cyclically recirculating data frame is used (Interbus protocol), then determined timing behavior is achieved, but every station requires special protocol chips making the system complex and expensive
Solution Approach 1:
The patent segments the data transmission into separate individual telegrams for each station instead of using a single cyclic data frame. Each telegram is independently addressed to a specific station, allowing stations to process only their designated telegrams without requiring complex protocol chips for frame manipulation.
Solution Approach 2:
Instead of having stations read and write to a circulating data frame (Interbus approach), the patent inverts the approach by having the master station send individually addressed telegrams that stations simply receive and process. This eliminates the need for stations to perform complex read/write operations on a circulating frame.
2Adaptability or versatility
If Ethernet telegrams with cyclic data frame are used, then communication between distributed stations is implemented, but protocol overhead is large requiring powerful communication systems
Solution Approach 1:
The patent extracts only the essential communication functionality needed for distributed station communication, eliminating unnecessary Ethernet protocol overhead. By using simple individually addressed telegrams instead of full Ethernet frames with cyclic data structures, the system achieves distributed communication with minimal protocol complexity.
3Quantity of substance
If traditional field bus systems are used for small data transmission, then data communication is achieved, but the system is too complex and expensive
Solution Approach 1:
The patent employs simple, inexpensive telegram structures that can be easily generated and processed without requiring expensive protocol chips. Each telegram is a self-contained, simple data unit that can be handled by basic communication hardware, making the system cost-effective for small data transmission applications.
4Productivity
If annular structure with circulating data frame is used, then data transmission is achieved, but line faults can disable the entire system
Solution Approach 1:
The patent segments the communication into independent individually addressed telegrams instead of a single circulating data frame in an annular structure. This segmentation means that a fault in one part of the system does not propagate through the entire circulation loop, allowing the system to continue operating even when line faults occur.
Data Source
AI summary
A control system has a plurality of spatially distributed stations. At least some of the stations have input connectors for connecting sensors or output connectors for connecting actuators. The stations are connected from station to station to form a series of stations. The series has a first station, at least one second station and a last station. The first station and every second station have a successor in the series. Every second station and the last station have a predecessor in the series. In order to transmit data in this control system, the first station generates a number of separate data telegrams which is equal to the number of second stations plus the last station. Each data telegram is addressed to precisely one of the stations. The first station sends the data telegrams on by one at defined time intervals to its successor, wherein the data telegrams are addressed in reverse order of the stations. Every second station receives a data telegram from its respective predecessor and sends the received data telegram to its respective successor in the manner of a bucket brigade until it receives a data telegram which is addressed itself. The second stations and the last station each generate an individual reply telegram which is directed to the first station, and send the individual reply telegrams to their respective predecessors in the manner of a bucket brigade.