Analysis and Design of Adaptive Cruise Control for Smart Electric Vehicle With Domain-Based Poly-Service Loop Delay

Domain-based electronic and electrical (E/E) architectures have been regarded as a possible upgrade to the distributed E/E architectures now used in electric vehicles (EV). In a distributed E/E design, E/E components are directly connected to the automobile bus. Domain-based architectures split E/E components into distinct domains depending on their functions, which clearly benefits software upgrading and wire harness reduction. However, due to its heterogeneous topology with multiple network protocols, domain-based E/E architecture introduces complicated multi-link and multi-node delays into the control loop. The delays may degrade and even deteriorate the stability of adaptive cruise control (ACC) employing domain-based E/E architecture. To this end, this paper proposes a heterogeneous-topology loop delay analysis by introducing a notion of poly-service (PS) loop delay. With a graphical pattern, the analytical process is presented in depth. The worst-case loop delay is calculated using an upper-boundary mathematic equation. Then, a hierarchical cyber-physical control method for ACC is designed. The upper level is intended to achieve desired acceleration based on vehicle and inter-vehicle motion states. And the lower level is intended to mitigate the negative impact of loop delays and provide reliable acceleration tracking. The results of co-simulation and Hardware-in-loop (HIL) experiment verify effectiveness of proposed approaches.