WO2017133210A1

WO2017133210A1 - Network system connecting to controllers in vehicle

Info

Publication number: WO2017133210A1
Application number: PCT/CN2016/094023
Authority: WO
Inventors: 李慧云; 唐烨; 严挺; 陈鸿刚; 毕亚雷
Original assignee: 中国科学院深圳先进技术研究院; 北京众享比特科技有限公司
Priority date: 2016-02-02
Filing date: 2016-08-08
Publication date: 2017-08-10
Also published as: CN105592165A; CN105592165B

Abstract

A network system connecting to controllers in a vehicle comprises: a fully distributed-based peer-to-peer network, configured to form an in-vehicle local area network (LAN) by taking controllers in a vehicle as nodes at a same level in the peer-to-peer network, wherein the controllers in the vehicle comprise an electronic control unit (ECU), a vehicle management system (VMS), an antilock brake system (ABS), an automated manual transmission (AMT), and another control unit; and the in-vehicle controllers realize, on the basis of the peer-to-peer network, data transmission and hardware resource sharing, and provide services. The invention employs a peer-to-peer network that adopts a fully distributed topology to connect all in-vehicle controllers. The network system comprises the features of decentralization, robustness, a high cost-performance ratio, and being easy to expand, increasing reliability and safety of an automotive electronic control system.

Description

Network system for connecting vehicle controller

Technical field

The invention belongs to the technical field of automobile control, and particularly relates to a network system for connecting an in-vehicle controller.

Background technique

Today, there are more and more electronic control systems in automobiles, such as electronic fuel injection devices, anti-lock braking systems (ABS), airbag devices, electric windows and doors, active suspensions, etc. Various sensors of the vehicle body are used to monitor the status information of the vehicle in real time and send status information to the corresponding control unit to achieve information sharing between the control units. For example, two signals in the engine control unit for indicating the engine speed and the accelerator pedal position need to be transmitted to the automatic transmission control unit, and the automatic transmission control unit will issue an upshift and downshift operation command accordingly.

At present, each vehicle controller communicates via a CAN (Controller Area Network) bus, as shown in Figure 1, which is based on a multi-master serial data communication protocol, and the communication medium can It is a twisted pair, coaxial cable or optical fiber. The CAN bus adopts a multi-master competitive bus structure, and integrates the physical layer and data link layer functions of the CAN protocol in the communication interface, which can complete the framing processing of communication data, including bit filling, data block coding, and cyclic redundancy. Inspection, priority discrimination, etc. There are two main ways to connect the CAN bus on the car. One is the high-speed CAN bus for the drive system, the speed can reach 500kb/s. The high-speed CAN bus is mainly connected to the engine control unit, ABS control unit, airbag control unit, and combination. These systems are directly related to the driving of automobiles. These systems require high-speed CAN bus to meet their requirements due to the large amount of information transmission and high requirements for information transmission rate. The other is low speed for body systems. The CAN bus has a speed of 100 kb/s. The CAN bus of the body system is mainly connected to the body system such as the central control lock, the electric door and window, the rear view mirror and the interior lighting, which have low requirements on the data transmission rate.

However, the CAN bus adopts a multi-master serial data communication protocol, and currently only a hub (HUB) communication mode can be realized. In the Hub mode of the C/S structure, the network is prone to a single point of failure problem, if the main information If the publisher fails, the entire network topology will have problems, which will reduce the reliability and security of the vehicle's electronic control system.

technical problem

In view of this, the embodiment of the present invention provides a network system for connecting an in-vehicle controller to solve the problem of low reliability and safety of the current automotive electronic control system.

Problem solution

Technical solution

An embodiment of the present invention provides a network system for connecting an in-vehicle controller, including:

Based on the fully distributed peer-to-peer network, each in-vehicle controller is used as an equal-status node in the peer-to-peer network to form an in-vehicle local area network;

The in-vehicle controller includes an electronic control unit ECU, a vehicle controller VMS, an automatic anti-lock ABS, an automatic transmission AMT, and other control units;

The in-vehicle controller implements data transmission based on the peer-to-peer network, shares hardware resources, and provides services. Advantageous effects of the invention

Beneficial effect

In the embodiment of the present invention, the peer-to-peer network of the full-distribution topology is used to connect the in-vehicle controllers, and the network system has the characteristics of decentralization, robustness, high cost performance and easy expansion, thereby improving the reliability of the vehicle electronic control system and safety.

Brief description of the drawing

DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the embodiments or the description of the prior art will be briefly described below. It is obvious that the drawings in the following description are only the present invention. For some embodiments, other drawings may be obtained from those of ordinary skill in the art in light of the inventive workability.

1 is an architectural diagram of a network system for connecting an in-vehicle controller provided by the prior art;

2 is a structural diagram of a network system for connecting an in-vehicle controller according to an embodiment of the present invention;

3 is a schematic diagram of an improvement of an in-vehicle controller according to an embodiment of the present invention;

4 is a structural diagram of an optimized network system according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of an improvement of an in-vehicle controller according to another embodiment of the present invention; FIG.

6 is a network topology simulation diagram provided by an embodiment of the present invention;

FIG. 7 is a diagram of simulation results provided by an embodiment of the present invention.

Invention embodiment

Embodiments of the invention

In the following description, for purposes of illustration and description However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the invention.

In the embodiment of the present invention, the in-vehicle controllers are connected by using a peer-to-peer (P2P) network, and the technical features of the peer-to-peer network are mainly embodied in:

1. Decentralization: The resources and services in the network are scattered on all nodes. The transmission of information and the implementation of services are directly carried out between nodes. It can avoid the possible bottlenecks without the intervention of intermediate links and servers. The decentralized basic characteristics of peer-to-peer networks bring advantages in terms of scalability and robustness.

2. Maintainability: In the peer-to-peer network, with the addition of users, not only the demand for services increases, but also the overall resources and service capabilities of the system are simultaneously expanded, and it is always easier to meet the needs of users. In theory, its scalability can be considered to be infinite.

3. Robustness: The architecture of peer-to-peer networks is inherently resistant to attack and high fault tolerance. Since services are distributed between nodes, the destruction of some nodes or networks has little effect on other parts. Peer-to-peer networks generally adjust the overall topology automatically when some nodes fail, maintaining connectivity of other nodes. Peer-to-peer networks are usually built in a self-organizing manner and allow nodes to join and leave freely.

4. Load balancing: In a peer-to-peer network environment, since each node is both a server and a client, the requirements for computing power and storage capacity of the traditional C/S structure server are reduced, and because resources are distributed among multiple nodes, better. Achieve load balancing across the entire network.

The topological relationship of the peer-to-peer network may include a centralized topology, a full-distribution topology, and a semi-distribution topology. In the embodiment of the present invention, in order to ensure equal status of the in-vehicle controllers in the network, the single-point fault is reduced. The system brings risk, adopts a fully distributed topology, and uses a random graph organization method, so that the target node can be quickly found and the propagation rate can be accelerated. At the same time, in the face of the dynamic changes of the network, the fully distributed topology also shows better fault tolerance, so it has better usability. As shown in FIG. 2, based on the fully distributed peer-to-peer network, each in-vehicle controller constitutes an in-vehicle local area network as an equal-status node in the peer-to-peer network, wherein the in-vehicle controller includes but is not limited to an electronic control unit ( Electronic Control Unit (ECU) (also known as "driving computer", "on-board computer", etc.), ABS, Vehicle Management System (VMS), Automated Mechanical Transmission (AMT) and other control units. Each in-vehicle controller implements data transmission based on peer-to-peer network, shares hardware resources and provides services. The services and contents provided by these hardware resources can be directly accessed by other peer nodes (Peer) without intermediate entities, so that each vehicle control The device is both an information/data provider (Server) and an information/data acquirer (Client). Once a network node fails, it will not affect the operation of other in-vehicle controllers. The network system has decentralization. The robustness, cost-effectiveness and ease of expansion have improved the reliability and safety of automotive electronic control systems.

Further, the above-described fully distributed topology can be extended to be structured. The above fully distributed topology should be accurately defined as a fully distributed unstructured topology. Here, a structured topological network can be constructed by introducing a distributed hash table (DHT), maintaining node location and routing information, and more. Find information efficiently.

Further, the other control unit may include an intelligent mobile terminal, which may serve as an extension unit of the in-vehicle controller, perform sensors such as images, temperature, or the like, or communicate with the roadside facility, and then pass the pair with the in-vehicle controller. The way the network is connected.

In the peer-to-peer network used in the embodiment of the present invention, the data link layer uses an Ethernet protocol and has strong scalability. The transport layer uses a User Datagram Protocol (UDP) protocol to implement network nodes. Data transfer. UDP protocol is a connectionless transport layer protocol in the Open System Interconnection (OSI) reference model. IETF RFC 768 is the formal specification of UDP. The main function of UDP protocol is to compress network data traffic into data packets. Form, a typical data packet is a binary data transmission unit, the first 8 bytes of each data packet is used to contain header information, and the remaining bytes are used to contain specific transmission data. Due to UDP number According to the higher priority communication right than TCP data, this makes UDP data communication faster. At the same time, compared with TCP protocol, UDP protocol has no complicated congestion control algorithm in TCP, cumbersome handshake process and retransmission. Strategy, therefore, using UDP to transfer data is very fast, and the TCP protocol is built into the system protocol stack, which is extremely difficult to improve, and the use of the UDP protocol is very flexible.

Further, data communication is implemented between the in-vehicle controllers by wireless transmission, which saves wiring costs and reduces high cost, so that the hardware is more flexible.

Communication protocols based on Ethernet and UDP, using wireless transmission communication methods, need to be improved on the basis of the traditional in-vehicle controller module. Since the conventional in-vehicle controller does not support the Ethernet protocol, in order to minimize the implementation or modification cost of the network system, in the embodiment of the present invention, the CAN-UDP protocol converter is used to solve the problem, and the vehicle is controlled. As an example, the improvement of the in-vehicle controller is shown in FIG. 3, wherein the conventional in-vehicle controller and related devices include a VMS and a CAN controller connected to the VMS, and in the embodiment of the present invention, the CAN control is performed. The CAN-UDP protocol converter is connected to the device, and the data buffer device is connected to the CAN-UDP protocol converter. The CAN-UDP protocol converter and the data buffer device are connected to the wireless transceiver through the network controller, thereby completing the connection with the other vehicle. Controller data communication. The optimized network system is shown in Figure 4.

Further, the UDP protocol may be an enhanced version of the UDP protocol, such as a UDP-based Data Transfer Protocol (UDT).

As another embodiment of the present invention, unlike the embodiment shown in FIG. 3, wireless transmission can be performed directly on the basis of the body controller without backward compatibility. As shown in FIG. 5, the vehicle controller directly connects data. The cache device, the data cache device is connected to the wireless transceiver through the network controller, thereby completing data communication with other controllers.

As an example, some of the devices added to the conventional in-vehicle controller module are selected as follows:

The data buffer device is implemented by a latch 74LS373 and a memory 93LC46, the network controller is implemented by an Ethernet controller RTL8019AS, and the wireless transceiver is implemented by the CC3200.

As an embodiment of the present invention, the data area of the UDP data may also be encrypted or signed using the DTLS (Datagram Transport Layer Security) protocol to ensure data security and/or identity authentication. Because the DTLS protocol is designed to run in the application space and does not require any kernel modifications, the cost of implementing encryption is also small.

In the past, the in-vehicle controller was interconnected by CAN bus, and the fully distributed peer-to-peer topology mode could not be realized. The embodiment of the invention adopts the peer-to-peer network as the wireless interconnection mode of the in-vehicle controller, and the following advantages can be obtained:

1, high performance. The interconnected mode based on the full-distribution topology has the characteristics of decentralization, so it belongs to a distributed architecture system, and there is no performance bottleneck between each node, and the bandwidth utilization is high.

2, high and strong, easy to expand. The fully distributed topology mode has the advantages of attack resistance and high fault tolerance, and the impact of a single network node on other nodes is small. The entire network automatically adjusts the overall topology when some network nodes fail, keeping the connectivity of other nodes. At the same time, because the new network node joins and the old network node exits has little impact on other network nodes, it has the characteristics of being easy to expand.

3. Privacy protection. The communication between the CAN buses is an insecure connection, and there is no reliable mechanism to ensure the confidentiality of the data transmission. The network transmission data in the embodiment of the present invention can be encrypted using a mature protocol to construct a secure communication channel.

In the following, the transmission delay between the network nodes in the network system connected to the in-vehicle controller provided by the embodiment of the present invention is detected according to requirements. Table 1 shows the transmission delay of the in-vehicle controller in different scenarios:

Table 1

[Table 1]

Here, the network simulation software OPNET is used to simulate the full-distribution topology network proposed by the embodiment of the present invention, and the ETE (End-to-End) delay of each node in the network is calculated, which is reliable and effective for the network. Sexuality was assessed objectively. OPNET is a network simulation software created by the Massachusetts Institute of Technology in 1986. Its rich model library facilitates the establishment of a network model and can develop the required model library according to its own needs. In a fully distributed topology, each network node is Etc., they have the same capabilities as the adjacent network nodes, so the topology diagram established is shown in Figure 6. In Figure 6, each network node simulates each in-vehicle controller. At the same time, the traffic between the network nodes is limited to control information, and the links between the five network nodes are set to point-to-point full-duplex. Each network node has two functions: first, the data packet is generated with a certain mathematical probability, and an integer is specified for the data packet to indicate the address of the data packet; second, the network node acts as a receiver of the data packet. When receiving a data packet, it is necessary to determine whether the destination address of the data packet is the network node, if yes, calculate the delay of the data packet, and after the calculation, destroy the data packet release space, if not, the data packet is forwarded. .

Set the different packet generation rate, run the simulation program, you can get the results shown in Figure 7:

It can be seen from Fig. 7 that the delays between nodes are different at different packet transmission rates, and the peak values of the two are 0.48 ms and 0.37 ms, respectively, but the two values do not exceed the end-to-end delay between the controllers in Table 1 ( 10ms). Therefore, the fully distributed network topology of the in-vehicle controller proposed by the embodiment of the present invention satisfies the actual use requirements.

The number of network nodes simulated in Figure 6 is five, which is considering that the actual number of in-vehicle controllers is on a small order of magnitude. The full-distribution topology uses flooding-based flooding (Flooding) discovery and random forwarding. (Random Walker) mechanism, so when the network scale increases dramatically, the network traffic will increase, but the number of controllers in the car is within a certain range, and this problem can be completely avoided.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the division of each functional unit and module described above is exemplified. In practical applications, the above functions may be assigned to different functional units as needed. The module is completed by dividing the internal structure of the device into different functional units or modules to perform all or part of the functions described above. Each functional unit and module in the embodiment may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit, and the integrated unit may be hardware. Formal implementation can also be implemented in the form of software functional units. In addition, the specific names of the respective functional units and modules are only for the purpose of facilitating mutual differentiation, and are not intended to limit the scope of protection of the present application. For the specific working process of the unit and the module in the foregoing system, reference may be made to the corresponding process in the foregoing method embodiment, and details are not described herein again.

One of ordinary skill in the art will recognize the various examples described in connection with the embodiments disclosed herein. The unit and algorithm steps can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the solution. A person skilled in the art can use different methods for implementing the described functions for each particular application, but such implementation should not be considered to be beyond the scope of the present invention.

In the embodiments provided by the present invention, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the system embodiment described above is merely illustrative. For example, the division of the module or unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be used. Combinations can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

The integrated unit, if implemented in the form of a software functional unit and sold or used as a standalone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the embodiments of the present invention may contribute to the prior art or all or part of the technical solution may be embodied in the form of a software product stored in a storage. The medium includes a plurality of instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor to perform all or part of the steps of the methods described in various embodiments of the embodiments of the present invention. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like. .

The embodiments described above are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art will understand that The technical solutions described in the examples are modified, or the equivalents of the technical features are replaced by the equivalents of the technical solutions of the embodiments of the present invention.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection of the present invention. Within the scope.

Claims

A network system for connecting an in-vehicle controller, comprising:

Based on the fully distributed peer-to-peer network, each in-vehicle controller is used as an equal-status node in the peer-to-peer network to form an in-vehicle local area network;

The in-vehicle controller includes an electronic control unit ECU, a vehicle controller VMS, an automatic anti-lock ABS, an automatic transmission AMT, and other control units;

The in-vehicle controller implements data transmission based on the peer-to-peer network, shares hardware resources, and provides services.
The network system of claim 1 wherein the data layer of the peer-to-peer network uses an Ethernet protocol and the transport layer uses a User Datagram UDP protocol.
The network system according to claim 2, wherein said UDP protocol comprises a UDP-based data transmission UDT protocol.
The network system according to claim 2, wherein each of said in-vehicle controllers performs data communication by means of wireless transmission.
The network system according to claim 3, wherein a CAN-UDP protocol converter is connected to the CAN controller of the in-vehicle controller, and a data buffer device is connected to the CAN-UDP protocol converter. The CAN-UDP protocol converter and the data cache device are both connected to the wireless transceiver through a network controller to perform data communication with other of the in-vehicle controllers.
The network system according to claim 3, wherein said in-vehicle controller is coupled to a data buffering device, said data caching device being coupled to said wireless transceiver via a network controller to perform completion with said other in-vehicle controller data communication.
A network system according to claim 5 or claim 6, wherein said data buffering means comprises a latch 74LS373 and a memory 93LC46, said network controller comprising an Ethernet controller RTL8019AS, said wireless transceiver comprising a CC3200.
The network system according to claim 2, wherein the data area of the UDP data is encrypted or signed using a packet transport layer security protocol DTLS.
The network system of claim 1 wherein the distributed hash table DHT Introducing the peer-to-peer network to build a structured network topology.
The network system of claim 1 wherein said other control unit comprises a smart mobile terminal.