Functional Safety Concept of “Minimum Risk Maneuver” in Conditional Driving Automation (Level 3) Vehicles

The concept of self-driving in automobiles were born before 100 years ago. The vision of Automated Driving is to make a future with fewer traffic accidents, less stress to drivers and increase productivity to road travellers. However, the increase in automation involves in increasing complexity in automotive electronics and software which challenges the safety of the road users. The conditional driving automation (Level 3) represents the first level of automation in which the automated driving system is capable of performing the complete Dynamic Driving Task (DDT) within a specific set of conditions; however, the driver has to be ready to take back control when the system reaches its design limits. In some cases, when driver may not be able to respond the fall-back ready user request, the system shall expect to perform the safe operation which is called “Minimum Risk Maneuver” (MRM). Defining the Functional Safety Concept (FSC) of MRM during the critical operating conditions are much important and challenging activity. In this paper, I present and discuss the concept and importance of MRM in Level 3 conditional automated driving platform, use cases, triggering conditions of MRM and various DDT performed by MRM and the concept of fail redundant systems / fail operational systems proposed in L3 platform with its functional higher-level architecture. I also describe an overview of Operational Design Domain (ODD), concept of Dynamic Driving Task (DDT) and Object and Event Detection and Response (OEDR) concepts in L3 system. Finally, the important topic of functional safety system level concepts, higher-level requirements for MRM function and some use case examples in Highway pilot / Auto-Lane change Assist (ALCA) functions.