Unmanned aircraft systems (UASs) are a promising technology that can improve the efficiency of infrastructure and plant equipment inspections and address labor shortages. UASs are anticipated to find applications in various fields, including Global Navigation Satellite System (GNSS)-denied areas such as tunnels and insides of plant buildings. However, to use UASs in such areas, service providers must ensure their adequate performance in situations with restricted GNSS-dependent functions. Thus, to advance the UAS industry, we develop test methods to evaluate UAS performance under some functions denied situations.
 Specifically, the developed test methods assess UAS mobility in narrow spaces where obstacles shield GNSS radio signals (Figs. 1, 2). Considering the applications of test methods in the UAS industry, we develop these methods through discussions with UAS users and manufacturers (Fig. 3). In addition, these test methods are designed to be conducted with ease; these test method fields comprise a simple structure, and the test procedure is simple. This research on test methods offers valuable insights for using advanced technologies such as AI and robots.

This paper is based on results obtained from a project (JPNP17004), “Drones and Robots for Ecologically Sustainable Societies Project,” commissioned by the New Energy and Industrial Technology Development Organization (NEDO).