Design considerations of a perception system in functional safety operated and highly automated mobile machines

Safe and reliable environmental perception is crucial for the highly automated or even autonomous operation of agriculture machines. However, despite the growing importance of robust perception systems, there is a lack of research on developing a generalized approach to designing and assessing their functional safety and reliability. This article describes the design and verification for the implementation of a functionally safe and reliable perception in a generalized manner. The normative references, ISO 25119, ISO 21448, and ISO 18497, which pertain to the functional safety design of highly automated mobile machines and vehicles, are introduced. This article explains the concept and considerations for designing a perception system. A new criterion "perception density" is proposed as a new standard unit to evaluate the spatial resolution of different types of perception sensors. To verify the performance of perception sensors, test scenarios were designed to address practical working conditions, including obstacles to be detected, foreseeable obscurity, test sites, and various lighting conditions. The test results were analysed and evaluated in light of the predetermined design considerations, and the perception sensors were quasi-numerically evaluated using the evaluation procedure.