RU2714557C2 - Anti-theft method of vehicle - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: method is proposed to counteract the theft of vehicle. Functional units of vehicle engaged with vehicle CAN-bus are blocked along information and supply lines, according to arming signal received from central processing unit of protection. Security unit is configured to implement the function of monitoring alarm events and control radio communication channels by locking devices. When an alarm event occurs, the central security unit locks the CAN bus by breaking at least part of its information and/or feed lines.

EFFECT: higher reliability of automotive security system.

1 cl

Description

The invention relates to the field of automotive industry and relates to the design of an automobile security system (AOS) of an alarm system used to set a vehicle for protection and control against illegal actions of third parties.

In particular, we are talking about an anti-theft system for cars and heavy vehicles, as well as special-purpose vehicles that use the CAN bus as an information channel.

In connection with the use of the CAN bus system in the car, it became apparent that these CAN buses can be used as a conductor communications system for connecting AOS. One of the most common options for connecting alarm systems to the CAN bus is the use of external CAN modules made in a separate housing (for example, the universal CAN adapter CAN-ART-A of the AGT tuning center (Moscow, http: //www.agt-company.ru/tu_eg_1_1), FALCON CAN-02 digital bus adapter for Mega-F Capital company (Moscow, http://www.mega-f.ru/fu/product/service_device / can / can-02 /), adapters of the AUTOCAN series, LLC "TEK Electronics" (Moscow, http://www.tec-electronics.ru/page.html?p=18&id=0).

The disadvantages of this kind of solutions include an increase in the number of additionally installed equipment and the increasing dimensions of the security complex, consisting of a security alarm system and an external CAN bus adapter module, which complicates the possibility of the system's covert installation in a vehicle, thereby reducing its security capabilities. In addition, the use of an external CAN bus adapter module requires the use of additional circuitry solutions providing for the possibility of matching the adapter with the alarm system installed on the vehicle, which limits the full functioning of the CAN bus module and the alarm system as a whole.

Established AOS vehicles are typically based on the operation of a standard immobilizer unit. The engine will not start until the immobilizer reads the access key.

The most popular third-party solutions use electromagnetic relays to control the electrical circuits of vehicles responsible for its normal operation. As a rule, such solutions are connected in a fairly standard way, which allows the hijacker to quickly unlock the AOS. The use of CAN-bus in such solutions serves only as a way to simplify the management of vehicle elements (doors, signals, etc.) in the implementation of security functions.

A fundamentally new approach was used in AOS “Igla”, where miniature electronic units were used, connected to the CAN bus and blocking the operation of vehicle components by acting on this bus. The search and elimination of blocking is complicated by the inability to quickly determine where the blocking device is hidden (RU 2613927, B60R 25/04, published on 03.22.2017).

AOS consists of a main unit containing a processor, a multiplex bus driver. The processor contains a control module, an authorization module, and a blocking module. AOS can be supplemented by a transceiver and an authorization unit, the main elements of which are the second processor and transceiver. The control module is associated with a user authorization module, a blocking module, and a bus driver. The control module, depending on the processed vehicle status data received from the computer bus driver of this tool and the authorization module, in case of detection of unauthorized control of the vehicle, issues a control signal to the lock module. The blocking module issues the necessary command through the driver to the computer multiplex bus of the vehicle, as a result of which the engine is turned off or the possibility of starting it is excluded.

Authorization of the owner can be carried out by successively pressing the standard buttons of the vehicle. This sequence is set by the owner himself in a specially provided password change mode.

The algorithm of this device is based on the blocking of the vehicle’s functional organs, which is carried out digitally by processing data and issuing NU commands via the vehicle’s multiplex data bus without breaking the vehicle’s standard wires.

The described AOS does not use encrypted CAN bus exchange, it is easy to access the bus and by submitting pre-known commands on this bus, you can open the doors, register new access keys, bypassing the immobilizer. The make, model and year of release of the vehicle uniquely determine the attack algorithm on the bus to unlock access. AOSs are quite easily detected during an attempted theft and are quickly deactivated, because operate on the principle of breaking the standard electrical circuits of the vehicle. The CAN bus in the direct operation of AOS, as a rule, is not involved at all.

The well-known AOC leaves the hijacker able to restore the vehicle to working capacity, knowing the installation location of the main unit block. The PIN code algorithm for unlocking the vehicle is transmitted over the CAN bus openly and can be listened to.

A more advanced solution is a car security system containing a car alarm unit made on a board on which at least one processor is mounted, connected to peripheral nodes made in the form of transceivers to provide communication with one part of the car’s standard equipment via the CAN bus of the latter. The system is equipped with a wireless communication unit installed on the circuit board of the car alarm unit and including a processor connected to the processor of the car alarm unit to organize an internal short-range wireless communication channel for another part of the standard vehicle equipment and additional distributed security system nodes equipped with transceivers for communication with the wireless unit processor communications (RU 2633141, B60R 25/00, publ. 11.10.2017).

This decision is made as a prototype.

A feature of this solution is the use of encrypted traffic of the radio channels of communication between the executive nodes and the processor part of the car alarm unit. But at the same time, it retains all the disadvantages inherent in the analogue of RU 2613927.

The present invention is aimed at achieving a technical result, which consists in increasing the reliability of an automobile security system in terms of preventing unauthorized use of a vehicle by breaking the power lines of actuators and issuing interference to the CAN bus that impedes the normal operation of this bus.

The specified technical result is achieved in that in the method of counteracting theft of the vehicle, which consists in blocking the vehicle functional units involved with the vehicle's CAN bus via the information and supply lines, according to the arming signal received from the central processor security unit, executed with the ability to implement the function of monitoring alarm events and controlling radio channels blocking devices, when an alarm event occurs Protection unit performs lock CAN-bus due to the rupture of at least part of its information and / or power supply lines.

In this case, if there is at least one signal in the CAN bus after breaking at least part of its information and / or supply lines, an interference signal is sent to the CAN bus.

These features are significant and interconnected with the formation of a stable set of essential features sufficient to obtain the desired technical result.

According to the present invention, the design of an automobile security system (AOS) for passenger and heavy vehicles, as well as special-purpose vehicles, is considered. A distinctive feature of the system is the guaranteed value of the time during which, with the alarm triggered, it will not be possible to operate the vehicle, even if the hijacker has full access to it and is familiar with the principle of operation and the features of AOS installation.

The essence of the claimed method of counteracting theft of a vehicle is that it blocks the functional components of the vehicle involved with the CAN bus of the vehicle via information and supply lines, according to the Arming signal received from the central processor security unit, configured to implement the function monitoring alarm events and controlling radio channels by locking devices. In this case, when an alarm event occurs, the central security unit locks the CAN bus due to breaking at least part of its information and / or supply lines. And if the process of transmitting at least one signal continues after the break of at least part of its information and / or supply lines in the CAN bus, an interference signal is sent to the CAN bus to exclude the possibility of full or partial functioning of the CAN bus for some functional nodes.

The CAN bus is a wired system that provides the connection of functional units with the on-board computer of the vehicle via information lines, as well as with the central processing unit of the AOS guard, connected to the CAN bus via the CAN module. The number of executive and / or functional units in a vehicle is a variable and may differ both in types of mechanisms and in their execution. As a rule, an immobilizer installed regularly by a manufacturer in a car is precisely organized to take into account the peculiarities of their execution to ensure that the vehicle is armed. But, as already indicated, these data are written in the digital markings of the vehicle and therefore it is not difficult for an experienced hijacker to find either the access code for the immobilizer or the vehicle's OSA, or to introduce interference in which the immobilizer or AOS ceases to respond to external disturbances.

In this regard, it is considered correct to act not on the end nodes, but on the system connecting them and providing the functionality of the entire vehicle. Damage to the CAN bus allows all functional units to be disconnected and to ensure the immobilization of the vehicle while all of these units remain operational.

Thus, the proposed AOC is a system that can be placed anywhere on the vehicle. The system is equipped with transceivers that provide communication of its nodes over the air. Moreover, the system itself is not connected by an immobilizer or other security system installed on the vehicle.

The system under consideration provides:

- the inability to analyze and replace data in the CAN bus to bypass the lock;

- the guaranteed long time required by the hijacker to unlock the vehicle, which makes the hijacking in the vast majority of cases impractical;

- a physical break in the vehicle’s electrical wiring makes the locking process irreversible without qualified service intervention. Access keys stolen from the owner of the vehicle at the time of the theft attempt, if the AOS has worked, will not help to unlock the vehicle;

- Replacement of the electronic engine control unit and immobilizer, as well as the exclusion of part of the CAN bus when attempting theft, will not lead to the desired result, because sensors will be blocked;

the distributed network architecture of AOS modules significantly increases the unlock time of all its elements.

Due to the multivariance of the execution of the system that implements the method of counteracting theft of a vehicle, the specific implementation of the system is not illustratively presented. However, the description of such a system at the block-functional level without illustration is given below.

The system includes a central processor protection unit (CBO), a diagnostic and programming device (UDP), which performs the functions of monitoring the status of the central bank, as well as functions to change the configuration parameters of the central bank, an emergency button (TC) - a device that transmits a signal about the state of the button to the central bank and which serves to change the security status of the vehicle, the bus interlock device (UBS) installed in the vehicle CAN-bus gap and irrevocably breaking it at the command of the Central Control Unit, the sensor interlock device (UBD) installed in the an integral sensor wiring harness and a signal blocking it upon a command from the central bank received via a radio channel.

Thus, AOS consists of many miniature blocks connected to the CAN bus. Their number may vary during installation, removing at least one device blocks the engine of the vehicle. AOS units can be connected to the CAN bus and to the sensor wiring. In the first case, they receive power directly from the bus, which allows them to be installed absolutely anywhere on the bus. In the second case, AOS units are powered by sensor supply lines and also do not require additional wiring.

When activating the alarm mode, the UBSh units physically break the bus in the place of their connection, making it impossible for the individual nodes of the vehicle to communicate. In the event that a signal is still present on the bus after a break, the CBO will interfere with it, interfering with the normal operation of the bus.

The UBD blocks of sensors physically break the information line of the sensor data, making it inoperative. Data exchange between the central unit and the sensor units occurs via an encrypted radio channel.

The above effects on the electrical equipment of the vehicle in case of alarm makes it impossible to quickly eliminate the causes, since the total number of blocks and their location is unknown.

The central bank is a complete device in a non-combustible plastic case, equipped with connectors for connecting to the external periphery located on the mobile unit of the vehicle, and equipped with a backup battery. The external periphery includes a connector for connecting to the CAN bus, which supplies the vehicle's on-board network.

The central bank is installed in the passenger compartment or in the car cabin (in the door niches, under the seat upholstery, behind the passenger compartment trim, behind the instrument panel, etc.) and has dual power supply, from the on-board network and from its own backup battery with automatic switching between them.

The central computer system makes it impossible to operate the vehicle in case of its unauthorized use with two degrees of protection, the CAN bus bus is noisy with random data and the bus is physically disconnected into separate sections that are unrelated to each other (depending on the number of UBS installed) in case of unauthorized use of the vehicle (moving, attempt hijacking, attempt to intervene in the vehicle’s electronic systems). The central bank operates in the following modes, disarmed (the central bank is awaiting arming), armed (the central bank is awaiting the occurrence of an alarm event and disarming), alarm (the central bank enters the software and hardware bus lock mode until the main and backup power supply disappear or until the command to change the mode via UDP is received), the lock mode (the central bank does not show itself, waiting for the command from the UDP to unlock).

The transition from the “armed” mode to the alarm mode is carried out according to the following criteria:

- Triggering of trailer doors and trunk.

- Vehicle movement at a speed of more than 10 km / h without an ignition key;

- The operation of the standard anti-theft system of the vehicle (according to the data in the CAN bus).

- The voltage drop of the vehicle electrical system below 6 V for 1 s;

- Pressing TC.

- Linear movement or acceleration of the vehicle in the absence of wheel movement.

The transition from the "alarm" mode to any other mode occurs only upon receipt of the appropriate command from the UDP.

The data transmitted via the CAN bus must be protected by encryption, excluding unauthorized exposure to the vehicle from the outside.

UBSh is included in the CAN-bus gap and has a connection to the vehicle’s common (negative) wire and receives the necessary power from the CAN bus signal lines. UBSh has a unique identifier that allows you to address a specific UBSh on the CAN bus. The UBSH monitors the data exchange on the CAN bus and periodically sends data on its status to the Central Bank. At the command of the Central Control Center, the UBSh must physically break two CAN-bus conductors passing through it. Further operation of this UBSh is not provided.

The UBD is connected to three wires going to the sensor: its power supply and signal output. The UBD receives power from the sensor power supply circuits. If connected to a two-wire sensor (crankshaft position sensor, etc.), the UBD must be powered by the circuits of this sensor, if the parameters of these circuits allow power supply of at least 4 V and current of at least 40 mA. For two-wire sensors, it is allowed to break either of the two wires. The UBD communicates with the Central Bank through a secure radio channel in the unlicensed frequency range of 868 MHz, the radio signal power should not exceed 10 mW. If it is impossible to use the frequency of 868 MHz, the UBD should be able to switch to a different frequency in the range 433 ... 868 MHz in agreement with the Central Bank. UBD has a unique identifier that allows you to address a specific UBD in the radio network. At the command of the Central Control Center, the UBD should break the signal conductor and provide a low voltage level on it, close to zero (with respect to the vehicle’s common wire), simulating a faulty sensor. Also, the supply conductor going to the sensor must be torn. The data transmitted over the air is protected by encryption, excluding unauthorized exposure to the vehicle from the outside.

The specific implementation of UBD and UBS in the framework of this application is not considered. The main thing is that these electronic nodes provide two modes of operation: the connection of two conductors and their separation. In fact. these are microimmobilizers (relays breaking the car circuits responsible for engine operation to prevent unauthorized use). These nodes also include radio components with support for Bluetooth Low Energy protocol specification 4.X for communication with the central bank

The present invention is industrially applicable and can be manufactured using technologies for building electronic security systems. The novelty of the claimed security system for a car lies in the use of regular tires of the car as communication conductors with its regular nodes, in the use of Bluetooth wireless communication as radio communication with additionally installed nodes, providing a break in bus lines. The combination of these three components makes it possible to install AOS of any architectural complexity with minimal interference with the layout of the car itself.

Claims (2)

1. A method of counteracting theft of a vehicle, which consists in blocking the vehicle’s functional units involved with the vehicle’s CAN bus via information and supply lines using an arming signal received from a central guard unit configured to implement the alarm monitoring function and control over the radio channels by locking devices, characterized in that when an alarm event occurs, the central security unit carries out blocking CAN-bus flashing due to breaking at least part of its information and / or supply lines. 2. The method according to p. 1, characterized in that if there is at least one signal in the CAN bus after breaking at least part of its information and / or supply lines, an interference signal is supplied to the CAN bus.