Ultra-Wideband for Distance Measurement and Positioning in Functional Safety Applications

Positioning techniques based on wireless communication systems are nowadays spreading in several diverse fields, such as factory automation, process control, distributed measurement, smart homes, and healthcare. Focusing on factory automation, such techniques may reveal particularly helpful to implement functional safety systems for applications, like mobile robotics, that involve the coexistence, and possibly the collaboration, of robots and human operators. Indeed, an effective localization system may be exploited by safety procedures to avoid harmful contacts between people and mobile equipment. In this paper we address the use of the Ultra-Wide-Band (UWB) technology to achieve positioning data, in such contexts. Specifically, after a short description of UWB, as well as of the typical positioning techniques, we discuss the general features of functional safety systems for mobile robotics, focusing on their common requirements. Then we provide the outcomes of an extensive measurement campaign in which we used UWB commercial components to evaluate the distance between devices as well as the position of mobile nodes. The obtained results are encouraging, since on the one hand they confirm the suitability of the proposed system whereas, on the other hand, they pave the way to future promising developments.