PROFINET Device Swap via MAC Address Mapping

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In robot systems, frequent tool changes lead to inefficiencies due to the need for multiple PROFINET devices with unique IP addresses and names, resulting in increased configuration and data efforts, and packet loss during device swaps, which slows down industrial automation processes.

Innovation Solution

Implementing a method where the network master detects disconnection from a first device, removes its address entry, and immediately creates an entry for a second device upon connection, eliminating the need for ARP query timeouts and allowing fast re-establishment of communication, enabling tools with the same IP address and different MAC identifiers to be swapped quickly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple PROFINET devices are configured with unique IP addresses for each interchangeable tool, then communication reliability is maintained, but configuration effort and data management complexity increase significantly

Engineering Contradiction:
Improvecommunication reliabilityVSAvoidconfiguration complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies universality by allowing multiple interchangeable tools (grippers, end effectors) to share a common IP address and PROFINET device configuration. Instead of each tool having a unique IP address, they all use the same IP address (e.g., 192.168.0.100) and device name, making the communication interface universal across different tool types. This reduces configuration complexity while maintaining communication reliability through MAC address tracking.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Reliability

If ARP timeout mechanism is used to detect device disconnection, then packet loss is prevented, but device change time increases to 1-2 seconds

Engineering Contradiction:
Improvepacket delivery reliabilityVSAvoiddevice change time
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by proactively detecting tool changes through robot controller signals before ARP timeout occurs. When the robot controller indicates a tool change, the system preemptively updates the MAC address mapping in the ARP table, rather than waiting for packet loss and timeout. This eliminates the 1-2 second delay while maintaining reliable packet delivery.

Inventive Principle:
Principle #10Preliminary action

3Ease of manufacture

If interchangeable tools have different MAC identifiers but same IP address, then configuration effort is reduced, but packet loss occurs during tool changes

Engineering Contradiction:
Improveconfiguration easeVSAvoidpacket delivery reliability
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent introduces an intermediary mechanism - a MAC address mapping table that mediates between the common IP address and the unique MAC identifiers of different tools. The PROFINET controller maintains this mapping, translating the shared IP address to the specific MAC address of the currently connected tool. This intermediary layer enables both configuration simplicity and reliable packet delivery without loss during tool changes.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP2643738B1Robot system comprising a robot and two devices that can be connected to said robot in an alternating manner, and method for changing said devices
Publication Date: 2019.07.03 KUKA DEUT GMBH
  • EP2643738B1 patent drawingFigure 1~3

AI summary

The invention relates to a method for changing devices (W1, D1; W2, D2) which are connected to a robot (R) and which communicate with a robot application (APP), having the following steps: S2: detecting a disconnection of a communication with a first device (W1, D1); S3: removing an address entry ("MAC1/IP1") for the first device from a communication index (ARP); S4: establishing communication with a second device (W2, D2); and S5: generating an address entry ("MAC2/IP1") for the second device in the communication index.