A Machine-Learning-Based Access Point Selection Strategy for Automated Guided Vehicles in Smart Factories

Abstract

Automated Guided Vehicles (AGVs) are becoming popular at many manufacturing facilities. To ensure mobility and flexibility, AGVs are often controlled by wireless communication, eliminating the constraints of physical cables. These AGVs require multiple Access Points (APs) to ensure uninterrupted coverage across the site. As AGVs move, they need to switch between these APs seamlessly. A primary challenge is that the communication downtime during this link-switching process must be minimal for effective AGV monitoring and control. Current AP selection strategies based on observed Received Signal Strength Indicator (RSSI) often fail in manufacturing environments due to RSSI’s inherent instability. This paper introduces a new AP selection technique for AGVs navigating these sites. Our approach harnesses the distinct movement patterns of AGVs and uses machine learning techniques to learn location-, trajectory-, and orientation-specific RSSI from the APs. Real-world factory data from our unique dataset revealed that our method extends the potential communication duration per route by 1.34 times compared to the prevalent signal strength-based switching methods commonly implemented in current drivers provided by chipset vendors or open-source Wi-Fi drivers. These results indicate that the automatic evaluation and tuning of the wireless environment using the proposed method is beneficial in reducing the time and effort required to investigate the detailed propagation paths needed to adapt AGV to existing APs.

Interaction between a Human and an AGV System in a Shared Workspace—A Literature Review Identifying Research Areas

“…Some researchers highlighted that communication with AGV must be bidirectional [58,69,70]. In the wireless communication systems described in [71], the important feature was the communication between sensors located on AGVs with Access Points (APs), based on which the truck's position in space could be determined. Other researchers assigned to this group prepared systems that enabled real-time co-working with AGV.…”