Vehicle Infotainment System Design And Implementation In Distributed Environment

With the intensification of competition in the domestic automotive industry,the vehicle entertainment system has gradually become the selling point and marketing focus of vehicles,and has been increasingly valued and strongly invested by various automotive enterprises.In order to achieve differentiation in the fierce market competition,various automobile enterprises have made different attempts.On the basis of the automobile factory’s own system,this project digs deeply into the existing functions and puts forward innovative points in order to provide better services to users.Based on the original single-machine system,the system has been expanded into a distributed on-board system.Different from the traditional way,the distributed on-board system deploys multiple independent display screens inside the vehicle,which supports multiple passengers in the front and rear seats to use independently at the same time.Its advantage is that it can serve the different needs of drivers and passengers at the same time.For example,while the driver uses navigation and Bluetooth phone,passengers can watch videos and use other applications.The research objectives of this project include three aspects.The first research goal is the cooperation between different modules of distributed system.The second research goal is how to share media files among different screens.How to design a system to meet the requirements of vehicle performance has become the third research goal of this topic.For the first research goal,after analyzing and comparing the distributed related technologies such as message queue and remote procedure call,the system chooses ZeroMQ and CORBA as the basic components and framework according to the application scenarios.After defining the functional and non-functional requirements of the system,this paper describes the logical architecture,communication architecture,and networking strategy of the system,and designs and implements the important functions of the system,including: system power status management,audio arbitration and voice channel management,media playback control,multi-screen synchronization management,vehicle performance optimization and so on.As the cornerstone of the whole system operation,the state of vehicle power will affect all the functions of the system.In this paper,the design factors of power supply state are discussed in detail.Based on these factors,eleven kinds of power states,transitions between the states,and the functional constraints of each state are defined and implemented.Vehicle audio channel is a competitive resource.There are many scenarios using car audio,such as Bluetooth calls,music playback,message reminders,navigation hints,speech recognition,etc.When these scenarios are concurrent,conflicts will occur.In this paper,the audio channel is rescheduled as a whole,and the arbitration rules and switching mechanism of the audio channel are established and implemented.For the second research goal,using the third party playback engine,this paper designs and implements a distributed Media playback scheme.A machine is responsible for device management and content retrieval,and another machine is responsible for playback control.In addition to individual Media playback,this paper also designs and implements Media multi screen synchronization scenarios.The so-called multi-screen synchronization refers to sharing content among multiple independent HMI modules,which mainly involves the establishment of session and the management of master and slave nodes.Unlike consumer electronics,the performance of vehicular systems are very demanding.As a distributed system,the start-up speed and the efficiency of inter machine communication are important factors that affect user experience.In view of these two aspects,for the third research goal,this paper discusses the optimization plan.The system guarantees software quality through multi-round testing,including unit testing,integration testing and multi-round acceptance testing.In this paper,test case design,defect record,test situation and acceptance result are described.After full testing and verification,the system was finally successfully launched.Finally,the future development trend of vehicle entertainment system is prospected.