Fraunhofer Institute for Integrated Circuits IISMobile robotics is playing an increasingly important role in manufacturing and intralogistics. However, stable and resilient networking is crucial to ensure that autonomous mobile robots (AMRs), automated guided vehicles (AGVs), and drones can work together reliably, safely, and in tight coordination. Our goal is to network mobile systems of every size, from the smallest fleet to the largest swarm, with absolute reliability. In various projects, we trial new ways to strengthen wireless links in automated factories. Our focus is on decentralized networking, which allows swarms of robots and drones to organize themselves to perform their tasks autonomously. In addition, we use intelligent combinations of different radio technologies (multi-RAT) as an important enabler of resilient communication systems.
Swarm networking
for automated factories
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Networked Mobile Robotics
Strong as a swarm: decentralized networking
With the right networking technologies, swarms of mobile robots or drones become highly flexible, self-organizing systems: no single central control, no fragile individual links to an overloaded base station. Instead, the devices set up a decentralized communication network and exchange data directly with each other. In this way, they make collective decisions and collaborate on completing tasks. And a swarm remains capable of action even if individual units fail.
Usually, the more devices are connected, the more data traffic hits the central server. The central control system then quickly becomes a bottleneck and single point of failure. Decentralized networking addresses this problem on three levels:
- Application level
Decentralized application components allow distributed systems to organize themselves directly, even when a central control system is unavailable. - Information distribution
When information from participants needs to be distributed to many others, traditional methods quickly reach the limits of scalability. Decentralized distribution mechanisms, coded procedures, or the use of geo-information open up new possibilities here. - Wireless networking
Short-term shadowing or sporadic interference jeopardizes the reliability of a radio system. Architectures such as mesh networks, sidelink, and multi-hop communication, which enable direct communication between participants, keep data flowing.
Multi-RAT communication: the key to resilient networking
Multi-RAT communication enables the parallel use of different radio technologies such as 5G, Wi-Fi, or LPWAN. Depending on availability, the system switches between different transmission standards to maintain data transmission even under harsh operating conditions. This is crucial when tight delay limits must be adhered to in order to keep drones, robots or vehicles operating safely. At the same time, swarms in industrial environments often face interference, shadowing, and varying radio conditions.
Through the parallel use of multiple radio technologies, data streams can be distributed redundantly, prioritized adaptively, and transmitted with precise timing. However, this requires a high degree of coordination and time-sensitive control of every transmission. To this end, we are developing a multi-RAT controller that distributes data packets intelligently across the available transmission channels, makes use of network coding, and adjusts the transmission and coding strategy proactively to the current radio and network situation. This gives rise to new processes and solutions that ensure the seamless and secure transmission of critical data even when conditions change rapidly.
Reference projects
ORPHEUS – Optimized networking of cooperating vehicle swarms
ORPHEUS – Optimized networking of cooperating vehicle swarms
The ORPHEUS project team is researching solutions that improve communication processes in cooperative transport systems. The project is funded by the German Federal Ministry for Economic Affairs and Energy with funds from the Industrial Collective Research (IGF) program.
Fraunhofer IIS is investigating how decentralized networking of driverless transport vehicles can be implemented in terms of communication technology. Various approaches are being simulated and evaluated for this purpose.
INVENT – Use of hybrid communication networks for time-sensitive, reliable networking of resilient, autonomous systems
INVENT – Use of hybrid communication networks for time-sensitive, reliable networking of resilient, autonomous systems
Within the INVENT project, a fail-safe radio communication solution that supports safety-critical drone operations is being developed. The application scenario is the early detection of forest fires by drones. The goal is to create a flight-ready communication system that uses multiple communication channels – including satellite communication, 5G, and Wi-Fi (multi-RAT) – to reliably transmit control and sensor data throughout the entire flight.
Fraunhofer IIS is developing a specially adapted multi-RAT controller for this purpose, which coordinates the control of data streams and automatically distributes data across suitable channels, in some cases redundantly. The use of radio coverage information is also being integrated in order to anticipate and avoid dead spots and bottlenecks. The project is funded by the Bavarian Ministry of Economic Affairs, Regional Development, and Energy.