Extended Reality (XR) technology serves as a crucial enabler in future of industry also known as Industry 4.0. By incorporating Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR), XR enables organizations to visualize complex data in real-time, conduct remote training and maintenance, and optimize operational workflows to mention the few of the use cases. This technology allows workers to interact with digital twins, receive real-time guidance through AR overlays, and collaborate virtually across distances, significantly enhancing productivity and decision-making capabilities while reducing operational risks and costs in the smart manufacturing environment.
A key requirement for the XR industrial applications to succeed is a low response time, which necessitates reliable, fast computing and communication. Is 5G and Edge Computing the solution? The obvious benefit of wireless connectivity compared to wired are mobility, flexibility and fast installation, whereas the potential drawback is the less deterministic or predictable performance.
Aalborg University (AAU) is a long-term distinguished academic partner (DAP) of Nokia, who (among others) have explored several Industry 4.0 use case scenarios (as listed below) under the supervision of Professor Preben Mogensen. This research is conducted using a 5G private network from Nokia and a powerful Edge Cloud server. The network setup in the AAU 5G smart production lab features a 5G SA (Stand Alone) CORE and three radio units configured as a Single-Frequency Network.
Headless robot use case
In this use case, we successfully offloaded the navigation of an industrial Autonomous Mobile Robot (AMR) to the Edge Cloud connected over 5G. All sensory information from the AMR, e.g., lidar, was streamed to the navigation and route planner on the Edge Cloud, which then sent the drive control information back to the AMR. The potential benefits are multiple: sensory information from all AMR in the fleet is available for control and route planning, it is easy to upgrade computation power, e.g., to support AI algorithms without mechanical touching of the individual AMRs, and reduced power drain on the AMRs.
Performance test of the headless robot, dynamically adding two obstacles in the drive-way
Related information can be found here: An Empirical Study of 5G, Wi-Fi 6, and Multi-Connectivity Scalability in an Indoor Industrial Scenario | IEEE Journals & Magazine | IEEE Xplore
Soft PLC use case
In the soft Programmable Logic Controller (PLC) use case, we transferred control of two synchronous robotic arms to the Edge Cloud, connected over 5G. We used an NTP (Network Time Protocol) server to time-synch the robotic arms to a time accuracy of better than 0.1 ms. To absorb any jitter injected by 5G or the Edge Cloud computing, we time-stamp control information “ahead of time” to make the control of the two robots fully synchronous. This is a simple way to achieve performance similar to Time-Sensitive Networks (TSN) implemented at a higher layer. In a second setup, one of the robotic arms was mounted on an AMR. The setup still facilitated synchronous control of the two robots, which a conventional PLC could not have achieved without a real TSN network.
Photo of the setup with soft PLC in Edge cloud and synchronous collaboration between a fixed robotic arm and a robotic arm mounted on an autonomous mobile robot
Virtual Reality glasses use case
We also trialed the use of Virtual Reality (VR) glasses in the lab, where the test person could move within the full extent of the lab and still be connected to the VR server on the Edge cloud. To overcome the interface limitations of Wi-Fi and the requirements of the VR glasses and VR content server to be on the same sub-network, we used a Wi-Fi/5G router for interfacing and a Virtual Private Network (VPN). The user experience of running VR over 5G and an Ege Cloud Server with powerful GPU was encouraging for enabling real Augmented Reality (AR) and VR applications in a larger industrial setting.
Logical diagram for test VR glasses connected over 5G private network and the VR app server in Edge Cloud.
For a deeper analysis of this use case, see the publication here: Cloud VR on 5G: A Performance Validation in Industrial Scenarios | IEEE Journals & Magazine | IEEE Xplore. These different studies of industrial scenarios provide tangible evidence of real-time industrial applications being enabled by fast, low-latency 5G communication and powerful Edge Cloud Computing.
AAU researchers also contributed 3GPP 5G-Advanced with innovative eXtended Reality (XR) technologies for reliable real-time streaming in the industrial applications (also known as Industrial Metaverse). Key contributions include link adaptation enhancements with code block group-based transmission, resulting in a 25% capacity increase, and application-aware scheduling policies for PDU sets, offering a 20% boost. Proactive inter-cell interference coordination ensures reliable communications even during heavy mobile broadband traffic. Recent research focuses on tethering, enabling communication via XR glasses and on-body terminals like smartphones, enhancing radio performance through intelligent multi-connectivity techniques, with plans for further 6G radio design extensions.
Related information can be found here:
- Enhancing Multi-Connected XR Device Performance With Soft Combining and Joint HARQ Processing in Cooperative Multicast | IEEE Journals & Magazine | IEEE Xplore
- Overview of NR Enhancements for Extended Reality (XR) in 3GPP 5G-Advanced | IEEE Journals & Magazine | IEEE Xplore
- Application Awareness for Extended Reality Services: 5G-Advanced and Beyond | IEEE Journals & Magazine | IEEE Xplore
