With the development of self-driving cars, large amounts of sensors controllers,
actuators and other devices will be integrated into autonomous driving system
and the electrical and electronic architecture of traditional vehicles needs to
be changed and upgraded. Therefore, this paper proposes a kind of autonomous
vehicle underlying control system, which inputs perception and decision
information and outputs control instructions to complete autonomous driving. The
original vehicle electrical system hardware and software had redesigned and
developed and a new electronic and electrical architecture for self-driving
vehicles is presented. The underlying control system was designed to solve the
problem of system integration and meet the upgrading requirements of data
calculation and real-time transmission in autonomous vehicles. In the paper, the
overall designing scheme of underlying control system introduces the underlying
control system architecture diagram and three-layer modular communication
architecture, then autonomous vehicles underlying control system hardware
circuit design, software design and experiments are separated illustrated. With
regards of hardware circuit, the underlying control system components, working
mechanism and the integration with perception module and positioning module were
designed and introduced. Moreover, with the consideration of data transmission
and system reliability, the software architecture, data communication and
control flow diagram were designed and explained. In addition, the control
system performance and functional experiments were implemented to validate the
underlying control system. Finally, it can be verified that the prototype
underlying control system for autonomous vehicles not only had good steering,
driving and braking characteristics, but also had a good performance in
self-driving car tracking, stopping and dynamic path planning functions.