Patent Description:
Patent Document <NUM> describes a configuration of a vehicle onboard network including hub devices (relays) such as a central gateway and an Ethernet (registered trademark)-CAN gateway. A plurality of ECUs are connected to the central gateway via Ethernet.

Patent Document <NUM> describes a technique of providing a gateway and a network hub (HUB) for relaying data transmission and reception between nodes of different networks in a vehicle onboard network system. Document <CIT> describes a vehicle onboard network including relays connecting sensors of the vehicle with a central controller.

In recent years, techniques related to vehicle automation for controlling vehicles depending on environment information inside and outside the vehicles, driver information, and so forth, including autonomous driving systems, have been developed. In the future, a computation function for autonomous driving and a control function for actuators are expected to be integrated in a central processing unit that centrally manages operations of the entire vehicle.

To such a central processing unit in which functions are integrated, if sensors and actuators are directly connected, an enormous amount of signal lines is required, and thus, the direct connection is not practical. In view of this, Patent Document <NUM> proposes a configuration of an onboard network by providing relay devices functioning as a network hub device and a gateway device.

Actuators mounted on a vehicle have various input/output circuit configurations, signal modes, and so forth. Therefore, interfaces between the relay devices and the actuators are to be devised. Specifically, in a case where a relay device is provided with an interface for a specific actuator, for example, the relay device might be dedicated and complicated, which leads to the possibility of cost increase and other problems.

It is therefore an object of the technique disclosed here to provide a vehicle onboard network system capable of avoiding complication of relay devices and maximizing versatility of the relay devices.

To achieve the object, the technique disclosed here is directed to a vehicle onboard network according to claim <NUM>.

In this aspect, in the vehicle onboard network system, each of the relay devices includes a plurality of general-purpose communication ports to which a common input circuit and/or a common output circuit is connected. With the communication port serving as a general-purpose port as described above, specialization and complication of the relay devices can be avoided. On the other hand, there are a variety of interfaces of onboard devices, as described above. In view of this, in the technique disclosed here, an onboard device (first onboard device) directly connectable to a general-purpose communication port is directly connected to the general-purpose communication port, whereas for an onboard device that is difficult to connect to a general-purpose communication port, a second interface device configured to perform interface conversion for the onboard device is interposed between the onboard device and the general-purpose communication port. This can avoid complication of the relay devices and maximize versatility of the relay devices.

In the vehicle onboard network system of this aspect, the first interface conversion device may include an analog-to-digital conversion circuit configured to convert the digital signal to an analog signal, the general-purpose communication ports may be analog ports to/from each of which the analog signal is input or output, and the second interface conversion device may include a regulator circuit disposed between the general-purpose communication port and the predetermined second onboard device.

With this configuration, analog devices having different driving capacities can be connected to a common communication port.

In the vehicle onboard network system of this aspect, the second interface conversion device and the second onboard device may be configured as one unit.

In the vehicle onboard network system of this aspect, the second onboard device may include a sensor and an actuator, and the vehicle onboard network system may further include an autonomous control circuit configured to autonomously control the actuator based on an output signal from the sensor with respect to a predetermined specific operation.

As described above, the technique disclosed here can avoid complication of relay devices and maximize versatility of the relay devices.

An exemplary embodiment will be specifically described hereinafter with reference to the drawings.

<FIG> schematically illustrates a part of a vehicle onboard network system <NUM> according to this embodiment. A vehicle <NUM> on which the vehicle onboard network system <NUM> is mounted is an automobile enabling assisted driving with assistance to driver's operation and autonomous driving without driver's operation, as well as manual driving by driver's operation. In the vehicle <NUM>, a X-by-wire technology of performing electrical control is employed in driving control, braking control, and steering control. That is, in this vehicle, operation of an accelerator pedal, operation of a brake pedal, and operation of a steering wheel are detected by sensors, and actuators are operated in response to control signals based on outputs from these sensors.

As illustrated in <FIG>, the vehicle onboard network system <NUM> includes onboard devices of a plurality of types. The onboard devices include a basic device related to basic operation of the vehicle, such as driving, braking, or steering, and a body-related device not related to any of driving, braking, and steering. The onboard device illustrated in <FIG> is an example of an onboard device included in the vehicle onboard network system <NUM>, and does not exclude the vehicle onboard network system <NUM> from including onboard devices other than the onboard devices illustrated in <FIG>.

Examples of the basic device include a driving-system device <NUM>, an electric power steering device (hereinafter referred to as an EPS device <NUM>), an automatic transmission, an electric brake device, and a dynamic stability control (DSC) device. The driving-system device <NUM> includes, for example, a throttle valve, a valve opening/closing mechanism, a fuel injection valve, a brake switch, and an air flow sensor. The EPS device <NUM> includes, for example, an electric motor, a steering switch, a steering warmer, and, in the case of a hydraulic system, an oil pump.

Examples of the body-related device include a power window device (hereinafter referred to as a P/W device <NUM>), a key less entry device <NUM>, a wiper device, a grille shutter, a headlamp <NUM>, a fog lamp, a horn, and a security alarm. The headlamp <NUM> is an example of a first onboard device.

In this embodiment, the vehicle <NUM> is divided into plurality of (seven in this embodiment) zones each of which is provided with a zone ECU <NUM>. The central ECU <NUM> is connected to these zone ECUs <NUM> in a daisy chain manner, thereby constituting a backbone network MNW. The central ECU <NUM> is an example of a central control device, and the zone ECUs <NUM> are examples of relay devices.

The backbone network MNW is configured to transmit a digital signal of a predetermined protocol. The predetermined protocol is not specifically limited, and is, for example, a protocol enabling high-speed large-capacity signal transmission, such as an Ethernet protocol or a CAN-FD protocol. In the following description, a signal transmitted in the backbone network will also be referred to as a backbone network signal. A signal transmission path from each zone ECU <NUM> to the onboard device will also be referred to as a "device-side network.

As illustrated in <FIG> and <FIG>, the central ECU <NUM> receives signals from a plurality of sensors <NUM> mounted on the vehicle <NUM>. The central ECU <NUM> generates a control signal for controlling onboard devices mounted on the vehicle, based on, for example, environment information inside and outside the vehicle acquired from the sensors <NUM> and/or a network (not shown) outside the vehicle. In the vehicle onboard network system <NUM> according to this embodiment, control signals for controlling the onboard devices are basically generated in the central ECU <NUM>, and transmitted from the central ECU <NUM> to the onboard devices via the zone ECUs <NUM>, for example.

The sensors <NUM> include a plurality of cameras <NUM> (see <FIG>) that are disposed on, for example, the vehicle body and take images of a vehicle-outside environment, and a plurality of radars <NUM> (see <FIG>) that are disposed on, for example, the vehicle body and detect an external target or other objects. Examples of the sensors <NUM> include a position censor, a passenger state sensor, a brake pedal sensor, a steering angle sensor, an accelerator pedal sensor, an outdoor air temperature sensor, an air conditioner pressure sensor, a fuel sensor, a mat sensor, a tank internal pressure sensor, a wheel speed sensor, a brake oil sensor, a Mastervac pressure sensor, a boost sensor, a clutch stroke sensor. The position censor detects a position of the vehicle (vehicle positional information) by using a global positioning system (GPS). The passenger state sensor acquires a state of a passenger of the vehicle including the presence/absence of the passenger. A brake pedal sensor acquires a pressing amount of the brake pedal by a driver of the vehicle. The steering angle sensor acquires a steering angle in steering by the driver of the vehicle. The accelerator pedal sensor acquires a pressing amount of an accelerator pedal by the driver of the vehicle. The sensors <NUM> here are example of sensors for providing the central ECU <NUM> with information for controlling operation of the vehicle <NUM>. That is, in this embodiment, it is not excluded that information is input to the central ECU <NUM> from a sensor except for the sensors described above.

Each of the cameras <NUM> is disposed to capture an image of the surroundings of the vehicle by <NUM>° in the horizontal direction. Each camera <NUM> captures an optical image showing a vehicle-outside environment to generate image data. Each camera <NUM> transmits the generated image data to the central ECU <NUM>.

In a manner similar to the cameras <NUM>, each of the radars <NUM> is disposed such that the detection range expands around the vehicle by <NUM>° in the horizontal direction. Information acquired by the radars <NUM> is transmitted to the central ECU <NUM>. The types of the radars <NUM> are not specifically limited, and a millimeter radar or an infrared radar may be used, for example.

Output signals from the sensors <NUM> may be directly input to the central ECU <NUM> in a manner similar to the information from the cameras <NUM> and the radars <NUM>, or may be input to the central ECU <NUM> via the zone ECUs <NUM> or other ECUs, for example.

As illustrated in <FIG>, the central ECU <NUM> includes a recognizer <NUM>, a route calculator <NUM>, a vehicle motion manager <NUM>, and a body-related manager <NUM>. The central ECU <NUM> is, for example, a processor constituted by one or more chips. The recognizer <NUM> recognizes environment information inside and outside the vehicle by using an artificial intelligence (AI) function, based on environment information from the cameras <NUM> and the radars <NUM>. The route calculator <NUM> calculators a route on which the vehicle is to travel, based on vehicle-outside environment information recognized by the recognizer <NUM>. The vehicle motion manager <NUM> calculates a target output of the basic device based on the vehicle-outside environment information recognized by the recognizer <NUM> and the route calculated by the route calculator <NUM>. The body-related manager <NUM> controls operation of the body-related device based on the vehicle-outside environment information recognized by the recognizer <NUM> and the route calculated by the route calculator <NUM>.

While the vehicle <NUM> onboard is performing manual driving or assisted driving, the central ECU <NUM> calculates a driving force, a braking force, and a steering angle to be output by each onboard device based on a detection value of the accelerator pedal sensor, the brake pedal sensor, or sensors of the steering system, for example. The central ECU <NUM> generates a target signal indicating target values of the calculated driving force, braking force, and steering angle, that is, a driving force, a braking force, and a steering angle to be obtained by each onboard device. In particular, during assisted driving of the vehicle <NUM>, the central ECU <NUM> takes target motion of the vehicle <NUM> described later into account in calculating a driving force, a braking force, and a steering angle.

To enable autonomous driving or assisted driving of the vehicle <NUM>, the central ECU <NUM> recognizes vehicle-outside environment information by the recognizer <NUM>, and calculates a route on which the vehicle <NUM> is to travel by the route calculator <NUM>. The central ECU <NUM> determines target motion of the vehicle <NUM> to follow the route calculated by the route calculator <NUM>.

Specifically, the recognizer <NUM> receives information from the sensors <NUM> and recognizes vehicle-outside environment information of the vehicle <NUM>. The vehicle-outside environment information includes a state of a target, a road condition, an ambient brightness, and so forth. Information on a target includes a relative position and a relative velocity of the target relative to the own vehicle, an attribute of the target (e.g., type and direction of movement), and so forth. Examples of the type of the target include other vehicles, pedestrians, roads, and road lane marking. The road information includes information on the shape of the road itself. The information on the road shape includes the shape of a traveling route (e.g., linear, curve, and curvature), a traveling route width, the number of lanes, the width of each lane, and so forth.

The recognizer <NUM> combines images of the outside of the vehicle captured by the cameras <NUM> and a recognition result of the target with information such as a relative distance from the target obtained by the radars <NUM>, and creates a 3D map showing a vehicle-outside environment. Based on the created 3D map, the recognizer <NUM> creates a 2D map for calculating a travel route of the vehicle <NUM>.

Based on the 2D map created by the recognizer <NUM>, the route calculator <NUM> calculates a travel route of the vehicle <NUM>. More specifically, based on the 2D map, the route calculator <NUM> calculates a travel route for avoiding an obstacle recognized by the recognizer <NUM>. The route calculator <NUM> calculates a plurality of candidate routes by a state lattice method, for example, and based on a route cost, selects one or more candidate routes from these candidate routes. The routes may be calculated by other techniques.

The vehicle motion manager <NUM> determines target motion of the vehicle for following a calculated travel route, and calculates a driving force, a braking force, and a steering angle for achieving the determined target motion. The vehicle motion manager <NUM> generates a target signal indicating target states of the calculated driving force, braking force, and steering angle, that is, a driving force, a braking force, and a steering angle to be obtained by each basic device. The central ECU <NUM> transmits the generated target signal to the zone ECUs <NUM>, as a digital signal of the predetermined protocol described above, via the backbone network MNW.

The body-related manager <NUM> generates control signals to body-related devices not related to any of driving control, braking control, and steering control of the vehicle <NUM>, based on the recognized vehicle-outside environment information and the calculated travel routes. For example, if the recognizer <NUM> recognizes that the surroundings are dark, the body-related manager <NUM> generates a control signal to be sent to the headlamp <NUM> so as to turn on the headlamp <NUM>, or if a window is open when the vehicle enters a tunnel, the body-related manager <NUM> generates a control signal to be sent to the P/W control device <NUM> so as to close a window. These control signals of the body-related device are also output as digital signals of the predetermined protocol described above.

The body-related manager <NUM> estimates a passenger's condition in the cabin by using a learned model generated by deep learning, based on information obtained by sensors for detecting the passenger' condition. The passenger's condition refers to a physical condition or feeling of a passenger. Examples of the physical condition of the passenger include healthy, mild fatigue, poor physical condition, and decreased consciousness. Examples of the passenger's feeling include fun, normal, bored, frustrated, and unpleasant. The body-related manager <NUM> generates control signals in consideration of the passenger's physical condition and/or the passenger's feeling. For example, if it is estimated that the temperature in the cabin is high and the passenger feels ill, the body-related manager <NUM> actuates an air conditioner and/or actuates the P/W control device <NUM> to open a window.

Each zone ECU <NUM> includes a communication port for connection to the backbone network MNW (hereinafter referred to as a backbone port) and a plurality of device-side communication ports for signal input/output to/from onboard devices. The backbone port is, for example, a port conforming to the Ethernet protocol. The central ECU <NUM> and each of the zone ECUs <NUM> are connected to each other, and the zone ECUs <NUM> are connected to one another by, for example, Ethernet communication cables. The zones may be defined in any manner, and if the number of zones varies, the number of zone ECUs <NUM> varies accordingly. A plurality of zone ECUs <NUM> may be disposed in one zone.

In this embodiment, the zone ECU <NUM> disposed in the right front of the vehicle will be referred to as a first zone ECU <NUM>. An example of the first zone ECU <NUM> will be described below.

As illustrated in <FIG>, the first zone ECU <NUM> includes a protocol converter <NUM>, a first signal converter <NUM>, a second signal converter <NUM>, and a third signal converter <NUM>. The first zone ECU <NUM> includes a backbone port <NUM>. The first zone ECU <NUM> includes communication ports 66a through 66c and 66e through <NUM> as device-side communication ports to be connected to the device-side network. The protocol converter <NUM>, the first signal converter <NUM>, the second signal converter <NUM>, and the third signal converter <NUM> are examples of the first interface conversion device.

The communication ports 66a through 66c are general-purpose digital communication ports, and onboard devices conforming to a CAN protocol can be connected to these ports. The communication ports 66e through 66f are general-purpose analog output ports, and the left and right headlamps <NUM> and <NUM> and an analog-driven actuator are connected to these ports. The communication ports 66e and 66f are general-purpose digital input ports, and a digital switch <NUM>, for example, is connected to these ports. The communication ports 66j and <NUM> are general-purpose analog input ports, and an analog sensor, for example, is connected to these ports. Although not specifically shown, the zone ECUs <NUM> include general-purpose ports of the same type. As described above, the communication ports of the same type are provided in the zone ECUs <NUM> and these communication ports are configured to have general-purposes so that a network system avoiding dedication and complication of the zone ECUs can be achieved. In a case where the configuration of the onboard network changes, such as a case where an onboard device to be connected is changed to another onboard device, for example, modification of the zone ECUs <NUM> can be minimized.

The zone ECU <NUM> (first zone ECU <NUM> in this example) and a peripheral configuration thereof will be specifically described below.

The protocol converter <NUM> includes: (a) the function of relaying communication between the central ECU <NUM> connected to the backbone port <NUM> and the zone ECU <NUM>, that is, a relay function of the backbone network MNW; (b) the distribution function of extracting and distributing a signal for an onboard device connected to the own ECU from backbone network signals; and (c) the collection function of collecting data to be transmitted from the onboard device connected to the own ECU to the central ECU <NUM> and/or other zone ECUs <NUM>. The (a) relay function is not significantly related to the technique disclosed here, and thus, will not be described in detail here, and the (b) distribution function and the (c) collection function will be mainly described below.

The protocol converter <NUM> receives a backbone network signal through the backbone port <NUM> and performs protocol conversion on this signal. For example, a backbone network signal conforming to an Ethernet protocol is subjected to protocol conversion to be converted to a digital conversion signal conforming to, for example, a controller area network (CAN) protocol, a CAN with flexible data-rate (CAN-FD) protocol, or a local interconnect network (LIN) protocol. The protocol conversion herein refers to an idea including data length conversion performed between a CAN-FD protocol and a CAN.

The protocol converter <NUM> extracts signals for onboard devices connected to the communication ports 66a through 66c from the digital conversion signals described above, and outputs the extracted signals from the communication ports 66a through 66c. The protocol converter <NUM> extracts signals for onboard devices connected to the communication ports 66e through <NUM> from the digital conversion signals described above, and outputs the extracted signals to the first signal converter <NUM>. The protocol converter <NUM> extracts signals for onboard devices connected to the communication ports <NUM> and 66i from the digital conversion signals described above, and outputs the extracted signals to the second signal converter <NUM>. The protocol converter <NUM> extracts signals for onboard devices connected to the communication ports 66j and <NUM> from the digital conversion signals, and outputs the extracted signals to the third signal converter <NUM>.

The communication port 66a is connected to, for example, an engine ECU <NUM>, which is connected to the driving-system device <NUM>. The communication port 66b is connected to, for example, an EPS-EPC <NUM>, which is connected to the EPS device <NUM>. The communication port 66c is connected to, for example, the P/W control device <NUM>, which is connected to a P/W switch 21c and a P/W motor 21d. The communication port 66c is connected to, for example, the key less entry device <NUM>. The communication ports 66e and 66f are respectively connected to, for example, the left and right headlamps <NUM> and <NUM>. The communication port <NUM> is connected to, for example, a signal conversion device <NUM>, which is connected to an analog-driven actuator <NUM>. The communication ports <NUM> and 66i are respectively connected to, for example, the digital switches <NUM> and <NUM>. The communication port 66j is connected to, for example, an analog sensor <NUM>. The communication port <NUM> is connected to, for example, a signal conversion device <NUM>, which is connected to an analog sensor <NUM>. The signal conversion device <NUM> is an example of a second interface conversion device.

The engine ECU <NUM> includes a first arithmetic unit 41a and a first signal processing unit 41b. The first arithmetic unit 41a calculates a controlled variable of the driving-system device <NUM> such that the driving-system device <NUM> obtains a target driving force, based on a signal of a target driving force transferred from the central ECU <NUM>. Examples of the controlled variable of the driving-system device <NUM> include an opening degree of a throttle valve and an injection timing of a fuel injection valve. The first signal processing unit 41b generates and outputs an analog signal to each actuator of the driving-system device <NUM> so as to obtain the controlled variable calculated by the first arithmetic unit 41a. With respect to a part of control of the driving-system device <NUM>, the engine ECU <NUM> may be configured to generate a control signal of the driving-system device <NUM>, irrespective of communication contents between the central ECU <NUM> and the engine ECU <NUM>. For example, if an engine water temperature detected by an engine water temperature sensor is high and knocking might occur in the engine, the engine ECU <NUM> generates a control signal to retard an injection timing of a fuel injection valve or an ignition timing of an ignition plug without passing through the central ECU <NUM>. As described above, the engine ECU <NUM> has a reflection control function of controlling the driving-system device <NUM> without passing through the central ECU <NUM>. A sensor <NUM> used for such a reflection control function is not connected to the zone ECUs <NUM> but is directly connected to an onboard device side (to the engine ECU <NUM> in this embodiment).

The EPS-ECU <NUM> includes second arithmetic unit 42a and a second signal processing unit 42b. The second arithmetic unit 42a calculates a controlled variable of the EPS device <NUM> such that the EPS device <NUM> obtains a target steering angle, based on information of a target steering angle transferred from the central ECU <NUM>. The controlled variable of the EPS device <NUM> is, for example, a current amount supplied to an electric motor for assistance. The second signal processing unit 42b generates and outputs an analog signal to the EPS device <NUM> so as to obtain the controlled variable calculated by the second arithmetic unit 42a. With respect to a part of control of the engine system <NUM>, the EPS-ECU <NUM> may be configured to generate a control signal for the EPS device <NUM>, irrespective of communication contents between central ECU <NUM> and the EPS-ECU <NUM>. For example, in a case where the controlled variable of the steering angle greatly deviates from an actually measured value of the steering angle sensor, the EPS-ECU <NUM> generates a control signal to reduce the difference in the steering angle, without passing through the central ECU <NUM>. As described above, the EPS-ECU <NUM> has the reflection control function of controlling the engine system <NUM> without passing through the central ECU <NUM>. The sensor <NUM> for use in such a reflection control function is not directed to the zone ECU <NUM> but is directly connected to the onboard device side (the EPS-ECU <NUM> in this embodiment). For example, the EPS-ECU <NUM> is configured to directly acquire outputs of at least a steering angle sensor, a vehicle speed sensor, and an engine speed sensor, for example.

The P/W control device <NUM> includes a signal converter 21a and a third signal processing unit 21b. The signal converter 21a converts P/W opening/closing control information transferred from the central ECU <NUM> to a signal in a mode capable of being received by the P/W motor 21d, and outputs the converted signal as an opening/closing control signal to the P/W motor 21d. When a passenger of the vehicle operates the P/W switch 21c for actuating the power window device, the third signal processing unit 21b outputs an opening/closing control signal based on the operation of the P/W switch 21c to the P/W motor 21d. Operation information of the P/W switch 21c is transferred to the central ECU <NUM> via the first zone ECU <NUM>. When the third signal processing unit 21b receives a switch signal from the P/W switch 21c, the third signal processing unit 21b controls the P/W motor 21d based on the switch signal from the P/W switch 21c, independently of a control signal from the central ECU <NUM>. As described above, the sensors or other devices for acquiring information having priority to an instruction from the central ECU <NUM> are not connected to the first zone ECU <NUM> but are directly connected to the onboard device side (the P/W device <NUM> in this embodiment). The signal converter 21a is an example of a second interface device. The P/W switch 21c is an example of a sensor. The P/W motor 21d is an example of an actuator. The third signal processing unit 21b is an example of an autonomous control circuit.

The key less entry device <NUM> incorporates a function (fourth signal processing unit 22a) of outputting a signal to an actuator 22b (e.g., door lock mechanism). This is because the key less entry device <NUM> is used only for locking and unlocking a door lock based on an on/off signal, and a signal itself is a simple signal.

The key less entry device <NUM> directly receives a signal concerning only actuation of the key less entry device <NUM> among signals from the sensors <NUM>. Specifically, the key less entry device <NUM> includes the fourth signal processing unit 22a, the actuator 22b, and a receiver 22c that receives a signal from a portable terminal <NUM> held by a passenger. When receiving a control signal for actuating the actuator 22b from the central ECU <NUM>, the fourth signal processing unit 22a converts the control signal to an analog signal. The fourth signal processing unit 22a transfers the converted analog signal to the actuator 22b and actuates the actuator 22b. A control signal from the central ECU <NUM> is a control signal generated by the central ECU <NUM> based on vehicle-outside environment information obtained from outputs of the sensors <NUM> and concerning an external environment of the vehicle. This control signal is a control signal for actuating the key less entry device <NUM>, independently of a signal from the portable terminal <NUM> described above.

<FIG> is an example of a circuit configuration of the first signal converter <NUM>. The first signal converter <NUM> includes a plurality of (three in <FIG>) analog output circuits having the same configuration. In <FIG>, the first signal converter <NUM> includes an analog output circuit 62a connected to the communication port 66e, an analog output circuit 62b connected to the communication port 66f, and an analog output circuit 62c connected to the communication port <NUM>. Although <FIG> does not show the output circuits 62b and 62c, the analog output circuits 62a through 62c, for example, are the same circuit. Here, the "same configuration" includes a circuit configuration in which parameters of elements and circuits, such as a driving capacity, a resistance value, and a capacitance value of a transistor, are different from one another, as well as completely the same circuit configuration including the same parameters of elements and circuits. The "same configuration" also includes a case where configurations for obtaining a main function are the same. As the output circuit, a circuit having high versatility is preferably employed, for example. The same holds for a digital input circuit, an analog input circuit, and a digital output circuit described later.

The analog output circuits 62a and 62b receive control signals (on/off control signals) of the headlamps <NUM> extracted by the protocol converter <NUM>, and based on the control signals, convert the control signals to analog signals and output the analog signals. The output signals from the analog output circuits 62a and 62b are directly input to the headlamps <NUM>. In the example of <FIG>, the interposition of an IPS device enables on/off control of the left and right headlamps <NUM> based on the output signals from the analog output circuits 62a and 62b. That is, the headlamps <NUM> receive analog control signals for actuation, directly from the first zone ECU <NUM>. As in the headlamps <NUM> in this example, an actuator capable of being directly driven by a general-purpose output circuit is directly connected to the first signal converter <NUM>. That is, such an actuator is directly connected to the communication port 66e through, for example, a connector (not shown). The configuration of the analog output circuit is not limited to the configuration illustrated in <FIG>, and may be other circuit configurations.

In a manner similar to the analog output circuits 62a and 62b, examples of the onboard device configured to be driven by an output circuit having a general-purpose configuration include a horn such as a burglar horn (anti-theft horn), a power outlet (voltage converter), a glove box illumination, a door illumination, a license lamp, a shift lock solenoid, a rear fog lamp, a high mounted stop lamp, a cargo lamp, an E-latch motor, a fuel lid opener, a canister, and a rear wiper.

The analog output circuit 62c receives a control signal for controlling the actuator <NUM> extracted in the protocol converter <NUM>, converts the control signal to an analog signal, and outputs the analog signal from the communication port <NUM>. As described above, the signal conversion device <NUM> is interposed between the communication port <NUM> and the actuator <NUM>. The signal conversion device <NUM> has the function of converting the analog signal output from the analog output circuit 62c to a signal in a mode capable of driving an actuator in a later stage. The signal conversion device <NUM> is an example of a second interface device.

Examples of an onboard device having difficulty in driving with a general-purpose output circuit and preferably having interposition of the signal conversion device <NUM> include a rear combination lamp, an electric fan of a PWM control method, an inverted wiper motor, an air conditioner actuator, a blower motor of a PWM control method, a PTC heater, an engine spark control (ESCL), an inner mirror, an indicator assy, a rear shade, a backup siren, a sunroof motor, and a change lever assy.

<FIG> illustrates an example of the circuit configuration of the second signal converter <NUM>. The second signal converter <NUM> includes a plurality of (two in <FIG>) digital input circuits having the same configuration. Specifically, in <FIG>, the second signal converter <NUM> includes a digital input circuit 63a connected to the communication port <NUM>, and a digital input circuit 63b connected to the communication port 66i. The configuration of the digital input circuit is not limited to the configuration of <FIG>, and may be other circuit configurations.

The digital input circuit 63a is configured to transfer an input signal from the digital switch <NUM> connected to the communication port <NUM>, to the protocol converter <NUM>. Similarly, the digital input circuit 63b is configured to transfer an input signal from the digital switch <NUM> connected to the communication port 66i, to the protocol converter <NUM>.

<FIG> illustrates an example of the circuit configuration of the third signal converter <NUM>. The third signal converter <NUM> includes a plurality of (two in <FIG>) analog input circuits having the same configuration. Specifically, the third signal converter <NUM> includes an analog input circuit 64a connected to the communication port 66j, and an analog input circuit 64b connected to the communication port <NUM>.

The analog input circuit 64a is configured to transfer an input signal (e.g., detection signal) from the analog sensor <NUM> connected to the communication port 66j, to the protocol converter <NUM>. The protocol converter <NUM> transfers an output result of the analog sensor <NUM> to the central ECU <NUM> and other zone ECUs.

Examples of the onboard device connectable to an input circuit having a general-purpose configuration, such as the digital input circuit 63a or 63b or the analog input circuit 64a, include sensors such as an outdoor air temperature sensor, a hood switch, a horn switch, an EVA sensor, an in-car sensor, and an accelerator pedal sensor, and switches such as a brake switch, a manual mode switch, a seatbelt switch, a cargo switch, a mode switch, an EPB switch, a parking switch, a tank internal pressure sensor, and a centralized lock switch.

The analog input circuit 64b is configured to transfer an input signal (e.g., detection signal) from the analog sensor <NUM> to the protocol converter <NUM> through the signal conversion device <NUM>. The protocol converter <NUM> transfers an output result of the analog sensor <NUM> to the central ECU <NUM> and other zone ECUs. The signal conversion device <NUM> is configured such that the analog sensor <NUM> can be connected to the common analog input circuit 64b in a case where the analog sensor <NUM> requires an additional terminal and/or an additional circuit in addition to the common analog input circuit 64b.

Examples of an onboard device for which processing is difficult with a general-purpose input circuit and interposition of the signal conversion device <NUM> is recommended, such as the case of the analog sensor <NUM>, include a current sensor for a battery, an ultrasonic sensor, an intrusion sensor, a rain sensor, a sunroof sensor, a steering angle sensor, a combination switch, a cluster switch, an air conditioner switch, a camera, and an ADAS radar.

As described above, in this embodiment, the common general-purpose communication port is provided to the zone ECUs <NUM>, and a predetermined onboard device connectable to this general-purpose communication port (corresponding to a first onboard device) is directly connected to the general-purpose communication port. In the case of a model different from an input/output circuit of the general-purpose communication port, such as a case where a special I/O is needed, an interface conversion device that performs interface conversion as in a signal conversion circuit is interposed. Accordingly, specialization and complication of the zone ECUs can be avoided. Accordingly, versatility of zone ECUs disposed at various locations in the vehicle can be maximized, and at least one of parts, members, circuit configurations, or specifications, for example, can be made common among the zone ECUs.

In the embodiment described above, the functions mounted on the zone ECUs <NUM> are functions as hub devices such as protocol conversion. For functions specific to onboard devices and/or onboard devices for use in controlling reflective operation, an ECU having an interface conversion function is interposed between the zone ECU <NUM> and the onboard devices. As described above, the zone ECUs are not provided with interfaces dedicated to onboard devices so that modification of the zone ECUs <NUM> by, for example, a change of connection target of the onboard device and/or a change of function of the onboard device itself can be minimized.

In the embodiment, the engine ECU <NUM> and the EPS-EPC <NUM> are described as examples of the ECU having the interface conversion function described above, but the disclosure is not limited to these examples. Examples of the ECU include an ECU for dynamic stability control (DSC), an ECU for tilt and telescopic, an ECU for an air bag, an ECU for power-train control module (PCM), an ECU for a TCM, an ECU for a 4WD unit, an ECU for a PLG, an ECU for an OHC, an ECU for an LFU, an ECU for a seat, an ECU for a connectivity master unit (CMU), and an ECU for a tuner amplifier unit (TAU). To the ECU for a DSC, a wheel speed sensor, a brake oil sensor, a Mastervac pressure sensor, a boost sensor, and a clutch stroke sensor, for example, are connected as onboard devices. To the ECU for a tilt and telescopic, a tilt and telescopic motor/sensor/switch, for example, is connected as onboard devices. To the ECU for a PCM, a brake switch and an air flow sensor, for example, are connected as onboard devices. To the ECU for a 4WD unit, a coupling assy and an oil temperature sensor, for example, are connected as onboard devices. To the ECU for a PLG, a PLG buzzer, a PLG motor/sensor/switch, a closer motor/switch, a touch sensor, and a room spot lamp, for example, are connected as onboard devices. To the ECU for an OHC, a center room lamp, a vanity mirror illumination, and a sunroof switch, for example, are connected as onboard devices. To the ECU for an LFU, an LF antenna and a door handle switch, for example, are connected as onboard devices. To the ECU for a seat, a seat warmer/sensor and a power seat motor/sensor/switch, for example, are connected as onboard devices.

In the embodiment described above, the central ECU <NUM> may also serve as the function of the zone ECUs <NUM>. In this case, an SSB switch, an accelerator pedal sensor, a not parking switch, a brake switch, and an ESCL, for example, are directly connected as onboard devices to the central ECU <NUM>.

In the embodiment, each of the signal conversion devices <NUM> and <NUM> may include a regulator circuit disposed between a communication port and a predetermined onboard device.

In this case, onboard devices having different driving capacities can be connected to a general-purpose port.

In the embodiment described above, the signal conversion device <NUM> is shown as a separate device from the analog sensor <NUM>. The signal conversion device <NUM> and the analog sensor <NUM> may be separately configured or may be configured as one unit (see <NUM> in <FIG>). The same holds for the signal conversion device <NUM> and the actuator <NUM> (see <NUM> in <FIG> and <FIG>). As described above, the signal conversion device <NUM> and the signal conversion device <NUM> are examples of a second interface device. The analog sensor <NUM> and the actuator <NUM> are examples of a second onboard device.

The forgoing embodiment is merely illustrative, and should not be construed to limit the scope of the present disclosure.

Claim 1:
A vehicle onboard network system (<NUM>) comprising:
a vehicle onboard central control device (<NUM>) configured to receive signals from a plurality of sensors (<NUM>) mounted on a vehicle (<NUM>) and generate a control signal for controlling onboard devices mounted on the vehicle (<NUM>); and
a plurality of relay devices (<NUM>) placed in respective zones in the vehicle (<NUM>) and connected to the vehicle onboard central control device (<NUM>) in a daisy chain manner via a backbone network MNW through which a digital signal of a predetermined protocol is transmitted,
characterized in that the plurality of sensors (<NUM>) being connected to the vehicle onboard central control device (<NUM>) via some of the plurality of relay devices (<NUM>),
the onboard devices being connected to the vehicle onboard central control device (<NUM>) via some of the plurality of relay devices (<NUM>), wherein
each of the relay devices (<NUM>) includes
a backbone-side communication port (<NUM>) connected to the backbone network MNW,
a plurality of device-side communication ports (<NUM>) connected to onboard devices, and
one or more first interface conversion devices (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) configured to perform interface conversion between the backbone-side communication port (<NUM>) and the plurality of device-side communication ports (<NUM>),
some of the plurality of device-side communication ports (<NUM>) are a plurality of general-purpose communication ports to which an input circuit and/or output circuit of a type identical to a type of another relay device (<NUM>) is connected, and
one or more onboard devices which are capable of being directly driven by an ordinary output circuit or one or more onboard devices which are capable of being directly connected to an ordinary input circuit are directly connected to a part of the plurality of general-purpose communication ports, whereas one or more specific onboard devices having difficulty in driving with an ordinary output circuit or one or more specific onboard devices for which processing is difficult with an ordinary input circuit are connected to another part of the plurality of general-purpose communication ports via one or more second interface conversion devices (<NUM>), the one or more second interface conversion devices (<NUM>) being configured to perform interface conversion.