Integrated network of Profibus-DP and IEEE 802.11 wireless LAN with hard real-time requirement

This paper focuses on a method to connect mobile devices such as mobile robots and automated guided vehicles (AGV) to a fieldbus. In this paper, the IEEE 802.11 wireless LAN is used to extend a Profibus-DP network for the mobile devices. In order to integrate these two networks, a protocol converter is developed that consists of two processes-master process of Profibus-DP and virtual master process of IEEE 802.11-and a transmission buffer. Furthermore, a virtual polling algorithm is developed at the protocol converter in order to satisfy real-time requirements on data communication.