autonomous driving system

Abstract

The present invention provides an automatic driving system, comprising: an off-vehicle sensor unit (3) for sensing the outside of a vehicle (2) and outputting an off-vehicle sensor signal (So); an on-vehicle control unit (4) for controlling the automatic driving of the vehicle based on the off-vehicle sensor signal from the off-vehicle sensor unit; a shielded cable (5) having a signal line (52) and a drain line (51) therein, wherein the signal line transmits the off-vehicle sensor signal from the off-vehicle sensor unit to the on-vehicle control unit, and the drain line is provided with a reference potential (V0); and an abnormality detection unit (6) for detecting an abnormality of the shielded cable. The abnormality detection unit generates a pulse signal (Sp) input to the drain line and monitors the potential of the drain line. The on-vehicle control unit inputs a pulse signal to the drain line at a stop timing (Ts) for stopping the transmission of the off-vehicle sensor signal by the signal line, and determines an abnormality of the shielded cable based on the potential of the drain line.

Description

Technical Field

[0001] The present disclosure relates to automated driving systems. Background Art

[0002] In the autonomous driving system, the in-vehicle control unit controls the autonomous driving of the vehicle based on sensor signals from the sensor unit inside the vehicle.

[0003] The sensor unit of the autonomous driving system disclosed in U.S. Patent No. 10,099,630 senses the outside world of the vehicle from outside the vehicle. In this autonomous driving system, the sensor unit outside the vehicle is connected to the in-vehicle control unit inside the vehicle via a wiring harness. However, in order to ensure the control accuracy of autonomous driving, it is important to suppress the transmission of erroneous signals caused by the superposition of noise from the outside world in the wiring harness that transmits signals from outside the vehicle to inside the vehicle. In addition, in order to ensure the control accuracy of autonomous driving, it is also important to suppress the transmission of erroneous signals caused by abnormalities such as degradation or disconnection in the wiring harness. Summary of the Invention

[0004] An object of the present disclosure is to provide an autonomous driving system that ensures control accuracy of autonomous driving.

[0005] An automatic driving system according to one embodiment of the present invention comprises: an off-vehicle sensor unit for sensing the outside world of the vehicle and outputting an off-vehicle sensor signal; an on-vehicle control unit for controlling the automatic driving of the vehicle inside the vehicle based on the off-vehicle sensor signal from the off-vehicle sensor unit; a shielded cable containing a signal line and a drain line inside, wherein the signal line transmits the off-vehicle sensor signal from the off-vehicle sensor unit to the on-vehicle control unit, and the drain line provides a reference potential; and an abnormality detection unit for detecting an abnormality of the shielded cable, the abnormality detection unit comprising: a pulse generating unit for generating a pulse signal input to the drain line; and a potential monitoring unit for monitoring the potential of the drain line, the on-vehicle control unit comprising an abnormality determination unit for inputting a pulse signal to the drain line in response to a stop timing for stopping the transmission of the off-vehicle sensor signal by the signal line, the abnormality determination unit determining an abnormality of the shielded cable based on the potential monitored by the potential monitoring unit.

[0006] According to the above system, since the signal line for transmitting the exterior sensor signal from the exterior sensor unit to the interior control unit and the drain line for providing the reference potential are contained within the shielded cable, the transmission of erroneous signals caused by superposition of noise from the outside can be suppressed.

[0007] In the above system, the abnormality detection unit for detecting abnormalities in the shielded cable includes a pulse generator that generates a pulse signal input to the drain line and a potential monitoring unit that monitors the potential. Furthermore, based on the timing at which transmission of the external sensor signal via the signal line ceases, the pulse signal is input to the drain line. The abnormality determination unit of the in-vehicle control unit determines abnormalities in the shielded cable based on the potential monitored by the potential monitoring unit. This effectively utilizes the stop timing that minimizes the impact on autonomous driving control, accurately determining abnormalities in the shielded cable and reducing the impact of erroneous signals on subsequent control.

[0008] The above structure can suppress control based on transmission of erroneous signals caused by superposition of noise from the outside and control based on erroneous signals generated due to abnormalities in the shielded cable, thereby ensuring the control accuracy of autonomous driving. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The above-mentioned object and other objects, features and advantages of the present disclosure will become more apparent from the following detailed description with reference to the accompanying drawings.

[0010] Figure 1 This is a block diagram showing the overall configuration of the autonomous driving system according to the first embodiment of the present disclosure.

[0011] Figure 2 This is a block diagram showing the detailed structure of the automatic driving system according to the first embodiment of the present disclosure.

[0012] Figure 3 This is a block diagram showing a detailed configuration of an automatic driving system according to a modified example of the first embodiment of the present disclosure.

[0013] Figure 4 This is a block diagram showing a detailed configuration of an automatic driving system according to a second embodiment of the present disclosure.

[0014] Figure 5 This is a block diagram showing a detailed structure of an automatic driving system according to a third embodiment of the present disclosure. DETAILED DESCRIPTION

[0015] Hereinafter, a plurality of embodiments will be described based on the accompanying drawings. In addition, there is a case where repeated descriptions are omitted by attaching the same reference numerals to corresponding constituent elements in each embodiment. In addition, when only a portion of a structure is described in each embodiment, the structure of another embodiment previously described can be applied to the other portion of the structure. Furthermore, not only the combination of structures clearly shown in the description of each embodiment, but also the structures of multiple embodiments can be partially combined with each other even if not clearly shown, if the combination does not particularly cause obstacles.

[0016] like Figure 1As shown, the autonomous driving system 1 of the first embodiment is installed in a vehicle 2. Vehicle 2 is capable of stable or temporary autonomous driving in an autonomous driving control mode. Here, the autonomous driving control mode can be achieved through autonomous driving control, such as conditional driving automation, highly automated driving, or fully automated driving, in which the system performs all driving tasks during operation. The autonomous driving control mode can also be achieved under highly assisted driving control, such as driving assistance or partial driving automation, in which the occupant performs some or all of the driving tasks. The autonomous driving control mode can also be achieved through any one of these autonomous driving controls and highly assisted driving controls, or a combination or switching between them.

[0017] like Figure 1 、 2 As shown, the automatic driving system 1 includes an off-vehicle sensor unit 3, an on-vehicle control unit 4, a shielded cable 5, and an abnormality detection unit 6. The off-vehicle sensor unit 3 is disposed outside the vehicle 2. The off-vehicle sensor unit 3 includes a housing 30, an off-vehicle sensor system 31, and an off-vehicle communication interface 32.

[0018] The housing 30 is formed of resin, metal, or a combination thereof, and is formed into a hollow, flat rectangular box, for example. The housing 30 is provided on the roof 20 constituting the vehicle body 2. The openings penetrating through the outer peripheral wall of the housing 30 are covered by a sensor cover such as transparent glass. Figure 1 As shown, each sensor cover is formed with an exposure window surface 33 exposed to the outside of the vehicle 2 .

[0019] like Figure 2 As shown, the off-vehicle sensor system 31 includes a plurality of external sensors 34. Each external sensor 34 is composed of, for example, a camera, a LiDAR (Light Detection and Ranging / Laser Imaging Detection and Ranging), a radar, and a sonar. Each external sensor 34 corresponds to an independent exposure window 33 and is housed inside the housing 30. Each external sensor 34 senses the outside of the vehicle 2 through the corresponding exposure window 33 outside the vehicle 2. Each external sensor 34 generates and outputs an off-vehicle sensor signal So as a sensing result, representing external information that can be used in the autonomous driving control mode.

[0020] The vehicle exterior communication interface 32 is primarily composed of, for example, a serial converter known as a serializer or deserializer. The vehicle exterior communication interface 32 is connected to each external sensor 34 via at least one of a LAN (Local Area Network), a wire, and an internal bus. The vehicle exterior communication interface 32 is grounded to the housing 30 of the external sensor unit 3 or the roof 20 of the vehicle 2, providing a reference potential V0 that serves as a reference for the signal voltage. The vehicle exterior communication interface 32 converts the external sensor signal So from each external sensor 34 into a serial signal, which is then output to the autonomous driving computer 41 (described later) of the vehicle interior control unit 4.

[0021] like Figure 3 As shown, the vehicle exterior communication interface 32 may also be connected to the at least one external sensor 34 via a processing circuit 35 that pre-processes the vehicle exterior sensor signal So from the at least one external sensor 34 ( Figure 3 Here, in particular, when at least two external sensors 34 are connected to the vehicle exterior communication interface 32 via the processing circuit 35, the vehicle exterior sensor signal So from each external sensor 34 can also be processed in advance in the processing circuit 35, such as Figure 3 After being integrated in this manner, the signals are outputted through the vehicle exterior communication interface 32. In this case, the output signal from the vehicle exterior communication interface 32 also corresponds to the vehicle exterior sensor signal So.

[0022] like Figure 1 、 2 As shown, the in-vehicle control unit 4 is arranged inside the vehicle 2. Figure 2 As shown, the in-vehicle control unit 4 includes an in-vehicle communication interface 40 and an autonomous driving computer 41. The in-vehicle communication interface 40 is primarily composed of, for example, a serial decoder known as a deserializer. The in-vehicle communication interface 40 is connected to the autonomous driving computer 41 via at least one of a LAN, a wire, and an internal bus. The in-vehicle communication interface 40 is grounded to the vehicle body 2 and is supplied with a reference potential V0, which serves as a reference for the signal voltage. The in-vehicle communication interface 40 decodes the exterior sensor signal So into a parallel signal and outputs it to the autonomous driving computer 41.

[0023] The autonomous driving computer 41 is primarily composed of at least one dedicated computer or the like. The dedicated computer constituting the autonomous driving computer 41 may be a driving control ECU that executes the autonomous driving control mode in the vehicle 2. The dedicated computer constituting the autonomous driving computer 41 may also be a positioning ECU that estimates vehicle 2 state quantities, including its own position. The dedicated computer constituting the autonomous driving computer 41 may also be a navigation ECU that guides the vehicle 2 along its travel path.

[0024] The autonomous driving computer 41 is also connected to the in-vehicle sensor system 7 via at least one of a LAN, a wire, a harness, and an internal bus. The in-vehicle sensor system 7 is installed inside the vehicle 2. The in-vehicle sensor system 7 includes an external sensor 70 and an internal sensor 71. The external sensor 70 is, for example, at least one of a camera, LiDAR, laser radar, millimeter-wave radar, and ultrasonic sonar, capable of sensing the outside world from within the vehicle 2. The internal sensor 71 is, for example, at least one of a vehicle speed sensor, an acceleration sensor, and a gyro sensor, capable of detecting physical quantities related to autonomous driving within the vehicle 2. The external sensor 70 and the internal sensor 71 generate an in-vehicle sensor signal Si representing the sensing or detection result, which is then output to the autonomous driving computer 41.

[0025] The automatic driving computer 41 has at least one memory and at least one processor. The memory is at least one non-transitory tangible storage medium such as a semiconductor memory, a magnetic medium, and an optical medium that non-temporarily stores programs and data that can be read by the computer. The processor includes, for example, at least one processor such as a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and a RISC (Reduced Instruction Set Computer)-CPU as a core. The processor executes multiple commands contained in the automatic driving control program stored in the memory. Thus, the automatic driving computer 41 constructs a driving control unit 42 and an abnormality determination unit 43 as multiple functional units (functional modules).

[0026] The driving control unit 42 executes the automatic driving control mode to control the automatic driving of the vehicle 2 from within the vehicle 2 based on the exterior sensor signal So from the exterior sensor system 31 of the exterior sensor unit 3 and the interior sensor signal Si from the interior sensor system 7. The abnormality determination unit 43 determines whether there is an abnormality in the shielded cable 5 based on a predetermined potential of the shielded cable 5 monitored by a potential monitoring unit 69 (described later) in the abnormality detection unit 6 for detecting an abnormality in the shielded cable 5.

[0027] like Figure 1 、 2 As shown, the shielded cable 5 is arranged from the outside to the inside of the vehicle 2. Figure 2As shown, the shielded cable 5 is interposed between the vehicle-exterior communication interface 32 of the vehicle-exterior sensor unit 3 and the vehicle-interior communication interface 40 of the vehicle-interior control unit 4. The shielded cable 5 is also interposed between the vehicle-exterior communication interface 32 and the abnormality detection unit 6. The shielded cable 5 is formed by including a drain wire 51 formed by a contact wire with the shield together with a signal wire 52 formed by an insulating covered wire by utilizing a shield formed by a common conductive layer. The common conductive layer forming the shield in the shielded cable 5 is a braided metal strand, a spiral winding, a conductive polymer layer, or the like. A preferred example of the shielded cable 5 is, for example, an LVDS (Low Voltage Differential Signaling) cable.

[0028] One end of the drain line 51 is grounded to the housing 30 of the exterior sensor unit 3 or the roof 20 of the vehicle 2 via a cable end on the exterior sensor unit 3 side, and is given a reference potential V0 such as 0 V. The other end of the drain line 51 is connected to a pulse line 60 (described later) of the abnormality detection unit 6 via a cable end on the interior control unit 4 side and on the abnormality detection unit 6 side, and is also connected to the autonomous driving computer 41 of the interior control unit 4 via this unit 6.

[0029] One end of the signal line 52 is connected to the vehicle exterior communication interface 32 via a cable end on the vehicle exterior sensor unit 3 side, and is also connected to each external sensor 34 of the vehicle exterior sensor unit 3 via this interface 32. The other end of the signal line 52 is connected to the vehicle interior communication interface 40 via a cable end on the vehicle interior control unit 4 side and on the abnormality detection unit 6 side, and is also connected to the automatic driving computer 41 of the vehicle interior control unit 4 via this interface 40. The signal line 52 transmits the vehicle exterior sensor signal So from the vehicle exterior sensor unit 3 to the vehicle interior control unit 4.

[0030] like Figure 1 、 2 As shown, the abnormality detection unit 6 is arranged inside the vehicle 2. Figure 2 As shown, the abnormality detection unit 6 includes a pulse line 60, a pulse generating unit 61, a switch line 62, a switch unit 63, a current-limiting resistor 64, a detection line 65, a floating line 66, capacitors 67a and 67b, an output line 68, and a potential monitoring unit 69. Each component of the abnormality detection unit 6 is packaged by being mounted on a circuit board. The abnormality detection unit 6 can also be fixed inside the vehicle 2. The abnormality detection unit 6 can also be configured to be mechanically and electrically removable from the vehicle 2 at the connection point of the pulse line 60 to the drain line 51, the connection points of the switch line 62 and the output line 68 to the in-vehicle control unit 4, and the connection point of the floating line 66 to the vehicle body.

[0031] The pulse line 60 is formed, for example, from substrate wiring, conductive wires, or a combination thereof. One end of the pulse line 60 is connected to the end of the drain line 51 on the side of the abnormality detection unit 6. The other end of the pulse line 60 is connected to the pulse generator 61. Thus, the pulse generator 61 is connected to the drain line 51 via the pulse line 60. The pulse generator 61 is primarily comprised of, for example, a pulse generator. The pulse generator 61 generates a pulse signal Sp having a predetermined voltage, shaped into a rectangular wave, at a predetermined period, and inputs the pulse signal to the pulse line 60.

[0032] The switch line 62 is formed, for example, from substrate wiring, wires, or a combination thereof. One end of the switch line 62 is connected to the autonomous driving computer 41 of the in-vehicle control unit 4. The other end of the switch line 62 is connected to a switch unit 63. The switch unit 63 is primarily composed of, for example, a semiconductor relay or a mechanical relay. The switch unit 63 is provided on the pulse line 60.

[0033] The switch unit 63 opens and closes the pulse line 60 between the drain line 51 and the pulse generator 61 based on a command signal Ss output from the automatic driving computer 41 to the switch line 62 in response to an abnormality determination process (described later) performed by the abnormality determination unit 43 in the in-vehicle control unit 4. Specifically, the switch unit 63 receives the command signal Ss for a close command to close the pulse line 60, thereby allowing the pulse signal Sp generated by the pulse generator 61 to be input to the drain line 51. On the other hand, the switch unit 63 receives the command signal Ss for an open command to open the pulse line 60, thereby blocking the pulse signal Sp generated by the pulse generator 61 from being input to the drain line 51.

[0034] The current-limiting resistor 64 is formed, for example, by a resistor element mounted on a substrate or a substrate resistive layer. The current-limiting resistor 64 is provided on the pulse line 60 between the drain line 51 side end and the switch section 63. The current-limiting resistor 64 limits the current actually flowing in the drain line 51 in response to the input of the pulse signal Sp to the pulse line 60. The current-limiting resistor 64 limits the current flowing in the drain line 51 to a set current value (maximum current value) or less, which is determined by the resistance value of the resistor 64 and the amplitude voltage of the pulse signal Sp.

[0035] Detection line 65 is formed, for example, from substrate wiring, a wire, or a combination thereof. One end of detection line 65 is connected to pulse line 60 between the drain line 51 end and current-limiting resistor 64, thereby branching off from pulse line 60. The other end of detection line 65 is connected to potential monitoring unit 69. Floating line 66 is formed, for example, from substrate wiring, a wire, or a combination thereof. One end of floating line 66 is connected to detection line 65 between the pulse line 60 end and potential monitoring unit 69, thereby further branching off from detection line 65. The other end of floating line 66 is connected to the vehicle body ground of vehicle 2, thereby providing a reference potential V0, such as 0V.

[0036] For example, capacitor 67a is formed by a ceramic capacitor or electrolytic capacitor mounted on a substrate, or a substrate dielectric layer. Capacitor 67a is provided on the pulse line 60 between the branch point of the drain line 51 and the detection line 65, thereby performing alternating current coupling (hereinafter referred to as AC coupling) between the drain line 51 and the pulse generating unit 61. For example, capacitor 67b is provided by a ceramic capacitor or electrolytic capacitor mounted on a substrate, or a substrate dielectric layer. Capacitor 67b is provided on the floating line 66, thereby performing AC coupling between the drain line 51 side of the potential monitoring unit 69 via the detection line 65 and the reference potential V0, thereby being in a floating state. In the first embodiment, the electrostatic capacitance C of capacitor 67a on the pulse line 60 and capacitor 67b on the floating line 66 are set to be substantially the same capacitance.

[0037] For example, the output line 68 is formed by substrate wiring, or a wire, or a combination thereof. One end of the output line 68 is connected to the potential monitoring unit 69. The other end of the output line 68 is connected to the automatic driving computer 41 of the in-vehicle control unit 4. For example, the potential monitoring unit 69 is mainly composed of a CMOS type or bipolar comparator. The first input end of the potential monitoring unit 69 is connected to the end of the detection line 65 on the opposite side of the pulse line 60, and is thereby connected to the drain line 51 via the pulse line 60. The second input end of the potential monitoring unit 69 is connected to the body ground of the vehicle 2, thereby providing a comparative potential Vc such as 1V. The potential monitoring unit 69 is connected to the end of the output line 68 on the opposite side of the automatic driving computer 41.

[0038] The potential monitoring unit 69 monitors the potential of the drain line 51 via the detection line 65. Specifically, when the potential of the drain line 51 exceeds the comparison potential Vc, the potential monitoring unit 69 outputs a monitoring signal Sm indicating the on-voltage to the output line 68. On the other hand, when the potential of the drain line 51 is less than the comparison potential Vc, the potential monitoring unit 69 outputs a monitoring signal Sm indicating the off-voltage to the output line 68. The comparison potential Vc is set to a value below which the potential of the drain line 51 can be determined to be abnormal due to, for example, deterioration, damage, or disconnection of the shielded cable 5.

[0039] Therefore, the abnormality determination unit 43, implemented by the autonomous driving computer 41 of the in-vehicle control unit 4, executes an abnormality determination process based on the monitoring signal Sm from the potential monitoring unit 69 to determine if the shielded cable 5 has an abnormality. Specifically, during the abnormality determination process, the abnormality determination unit 43 determines the stop timing Ts for stopping the transmission of the exterior sensor signal So via the signal line 52. In this case, the stop timing Ts is determined based on at least one of the exterior sensor signal So from the exterior sensor unit 3 and the interior sensor signal Si from the interior sensor system 7. For example, the stop timing Ts can be determined based on whether the cutoff voltage of the exterior sensor signal So continues for a set period. Alternatively or in addition, the stop timing Ts can be determined based on whether the vehicle speed indicated by the interior sensor signal Si from the vehicle speed sensor in the interior sensor system 7 remains at a value of zero for a set period (i.e., the vehicle 2 is stopped). The latter determination is used to determine if the cutoff voltage of the exterior sensor signal So continues for the set period due to an abnormality in the shielded cable 5. By such determination, the stop timing Ts is set, for example, when the system of the vehicle 2 is initialized or when the vehicle 2 stops at an intersection.

[0040] During the abnormality determination process, the abnormality determination unit 43 outputs a command signal Ss indicating a close command from the automatic driving computer 41 to the switch unit 63 via the switch line 62 at the stop timing Ts. As a result, if the pulse signal Sp from the pulse generator 61 is input to the drain line 51 at the stop timing Ts, and the potential monitoring unit 69 outputs a monitoring signal Sm indicating an on-voltage via the output line 68, the abnormality determination unit 43 determines that the shielded cable 5 is normal. Specifically, if the potential of the drain line 51 is within the allowable range, the shielded cable 5 is determined to be normal based on this potential. On the other hand, if the pulse signal Sp is input to the drain line 51 at the stop timing Ts, and the potential monitoring unit 69 outputs a monitoring signal Sm indicating an off-voltage via the output line 68, the abnormality determination unit 43 determines that the shielded cable 5 is abnormal. Specifically, if the potential of the drain line 51 is outside the allowable range, the shielded cable 5 is determined to be abnormal based on this potential.

[0041] During the abnormality determination process, the abnormality determination unit 43 outputs the command signal Ss indicating the opening command from the automatic driving computer 41 to the switch unit 63 via the switch line 62 at times other than the stop timing Ts. At this time, the abnormality determination unit 43 stops determining whether the shielded cable 5 is normal or abnormal.

[0042] (Effect)

[0043] Hereinafter, the effects of the first embodiment described above will be described.

[0044] According to the first embodiment, since the signal line 52 for transmitting the exterior sensor signal So from the exterior sensor unit 3 to the interior control unit 4 and the drain line 51 for providing the reference potential V0 are contained inside the shielded cable 5, the transmission of erroneous signals caused by the superposition of noise from the outside can be suppressed.

[0045] Furthermore, according to the first embodiment, the abnormality detection unit 6 for detecting an abnormality in the shielded cable 5 includes a pulse generating unit 61 for generating a pulse signal Sp input to the drain line 51, and a potential monitoring unit 69 for monitoring the potential. Therefore, according to the first embodiment, in response to the input of the pulse signal Sp to the drain line 51 at the stop timing Ts, at which transmission of the external sensor signal So via the signal line 52 is stopped, the abnormality determination unit 43 of the in-vehicle control unit 4 determines an abnormality in the shielded cable 5 based on the potential monitored by the potential monitoring unit 69. By effectively utilizing the stop timing Ts, which minimizes the impact of autonomous driving control, an abnormality in the shielded cable 5 can be accurately determined, and the impact of erroneous signals on subsequent control can be reduced.

[0046] In summary, the first embodiment ensures the accuracy of autonomous driving control by suppressing the transmission of erroneous signals caused by superimposed noise from the outside world and by controlling erroneous signals due to abnormalities in the shielded cable 5. This is also effective in ensuring the safety of the intended function (SOTIF).

[0047] According to the first embodiment, the stop timing Ts is determined based on at least one of the exterior sensor signal So from the exterior sensor unit 3 and the interior sensor signal Si from the interior sensor system 7 that senses the outside world within the vehicle 2. Thus, the stop timing Ts is appropriately set to minimize the impact of the autonomous driving control, thereby ensuring the control accuracy of the autonomous driving.

[0048] According to the first embodiment, a current-limiting resistor 64 is provided between the drain line 51 and the pulse generator 61 in the abnormality detection unit 6 to limit the current flowing in the drain line 51 to a set current value or less. This limits the DC and AC currents actually flowing in the drain line 51 due to the input of the pulse signal Sp, and reduces the potential of the pulse signal Sp actually applied to the drain line 51. This mitigates the generation of line stress in the shielded cable 5, which can cause abnormalities, and contributes to ensuring control accuracy in autonomous driving.

[0049] According to the first embodiment, AC coupling is performed between the drain line 51 and the pulse generator 61 in the abnormality detection unit 6 via the capacitor 67a. This limits the DC current and AC current that actually flow through the drain line 51 due to the application of the pulse signal Sp. This mitigates line stress in the shielded cable 5, which can cause abnormalities, and contributes to ensuring control accuracy in autonomous driving.

[0050] According to the first embodiment, in the abnormality detection unit 6, the drain line 51 side of the potential monitoring unit 69 is AC-coupled to the reference potential V0 via the capacitor 67b. This allows a portion of the AC current generated by the input pulse signal Sp to be released to the reference potential V0 side, limiting the DC and AC currents actually flowing in the drain line 51. This mitigates line stress in the shielded cable 5, which can cause abnormalities, and contributes to ensuring control accuracy in autonomous driving.

[0051] According to the first embodiment, in the abnormality detection unit 6, which establishes AC coupling between the drain line 51 side of the potential monitoring unit 69 and the reference potential V0 via a capacitor 67b, a current-limiting resistor 64, located between the drain line 51 and the pulse generator 61, limits the current flowing in the drain line 51 to a set current value or less. This enhances the ability to limit the DC and AC currents actually flowing in the drain line 51 due to the input of the pulse signal Sp. This mitigates the generation of line stress in the shielded cable 5, which can cause abnormalities, and contributes to ensuring control accuracy in autonomous driving.

[0052] According to the first embodiment, in the abnormality detection unit 6, in which AC coupling is performed between the drain line 51 side of the potential monitoring unit 69 and the reference potential V0 via capacitor 67b, AC coupling is performed between the drain line 51 and the pulse generating unit 61 via capacitor 67a. This improves the effect of limiting the DC and AC currents that actually flow through the drain line 51 due to the input of the pulse signal Sp, depending on the capacitance ratio between capacitors 67a and 67b. In particular, in the first embodiment, by setting the capacitances C of capacitors 67a and 67b to be substantially equal, a high degree of limiting the DC and AC currents on the drain line 51 can be ensured.

[0053] According to the first embodiment, the abnormality determination unit 43 of the in-vehicle control unit 4 closes the switch unit 63, which opens and closes between the drain line 51 and the pulse generator 61, at the stop timing Ts. On the other hand, the switch unit 63 is opened at times other than the stop timing Ts. This allows the input timing of the pulse signal Sp to the drain line 51 to be limited to the stop timing Ts required for abnormality detection in the shielded cable 5. This mitigates the generation of line stress in the shielded cable 5, which can cause abnormalities, and contributes to ensuring control accuracy in autonomous driving.

[0054] According to the first embodiment, the abnormality detection unit 6 may be detachably provided in the vehicle 2. In the case of being detachable, the abnormality detection unit 6 may be used as a maintenance kit before servicing the vehicle 2, for example.

[0055] (Second embodiment)

[0056] like Figure 4 As shown, the second embodiment is a modification of the first embodiment.

[0057] In the second embodiment, the capacitance Ca set in the capacitor 67a on the pulse line 60 is larger than the capacitance Cb set in the capacitor 67b on the floating line 66. This allows the DC current and AC current actually flowing in the drain line 51 due to the input of the pulse signal Sp to be limited, and increases the hysteresis of the potential input to the potential monitoring unit 69 when the shielded cable 5 is normal and when an abnormality occurs, thereby improving the accuracy of abnormality determination.

[0058] (Third embodiment)

[0059] like Figure 5 As shown, the third embodiment is a modification of the first embodiment.

[0060] In the third embodiment, the capacitance ca set in the capacitor 67a on the pulse line 60 is smaller than the capacitance cb set in the capacitor 67b on the floating line 66. This significantly limits the DC current and AC current that actually flow through the drain line 51 due to the input of the pulse signal Sp, thereby enhancing the effect of alleviating the generation of line stress on the shielded cable 5.

[0061] (Other embodiments)

[0062] Although a plurality of embodiments have been described above, the present disclosure is not to be construed as being limited to these embodiments, and can be applied to various embodiments and combinations within a scope not departing from the gist of the present disclosure.

[0063] In a modified embodiment, the dedicated computer constituting the autonomous driving computer 41 may include at least one of a digital circuit and an analog circuit as a processor. Examples of digital circuits include at least one of an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), an SOC (System on a Chip), a PGA (Programmable Gate Array), and a CPLD (Complex Programmable Logic Device). Furthermore, such digital circuits may include memory for storing programs.

[0064] In a modified example, the current-limiting resistor 64 and at least one of the capacitors 67a and 67b may not be provided. In a modified example, the switch unit 63 may not be provided. When the pulse generator 61 connected to the switch line 62 receives the command signal Ss of the closing command corresponding to the closing command at the stop timing Ts, it generates the pulse signal Sp, and stops generating the pulse signal Sp at times other than the stop timing Ts.

[0065] While the embodiments, structures, and methods of the autonomous driving system disclosed herein are exemplified above, the embodiments, structures, and methods of the present disclosure are not limited to the aforementioned embodiments, structures, and methods. For example, embodiments, structures, and methods obtained by appropriately combining the technical components disclosed in different embodiments, structures, and methods are also included in the scope of the embodiments, structures, and methods of the present disclosure.

Claims

1. An autonomous driving system comprising: An off-vehicle sensor unit (3) senses the outside of the vehicle (2) and outputs an off-vehicle sensor signal (So); an in-vehicle control unit (4) for controlling the automatic driving of the vehicle based on the external sensor signal from the external sensor unit; A shielded cable (5) contains a signal line (52) and a drain line (51) inside, wherein: The signal line transmits the exterior sensor signal from the exterior sensor unit to the interior control unit, and the drain line is provided with a reference potential (V0); and An abnormality detection unit (6) detects abnormality of the shielded cable, The above-mentioned abnormality detection unit has: a pulse generating unit (61) for generating a pulse signal (Sp) to be input to the drain line; and A potential monitoring unit (69) monitors the potential of the drain line. The above-mentioned in-vehicle control unit has an abnormality determination unit (43) that inputs the above-mentioned pulse signal to the above-mentioned drain line in response to the stop timing (Ts) of stopping the transmission of the above-mentioned external sensor signal performed by the above-mentioned signal line, and the above-mentioned abnormality determination unit determines the abnormality of the above-mentioned shielded cable based on the potential monitored by the above-mentioned potential monitoring unit.

2. The automatic driving system according to claim 1, wherein: The abnormality determination unit determines the stop timing based on at least one of the exterior sensor signal from the exterior sensor unit and the interior sensor signal (Si) from an interior sensor system (7) mounted inside the vehicle.

3. The automatic driving system according to claim 1, wherein: The abnormality detection unit includes a current limiting resistor (64) between the drain line and the pulse generating unit, wherein the current limiting resistor limits the current flowing in the drain line to a set current value or less.

4. The automatic driving system according to claim 1, wherein: The abnormality detection unit includes a capacitor (67a) that performs AC coupling between the drain line and the pulse generating unit.

5. The automatic driving system according to claim 1, wherein: The abnormality detection unit includes a capacitor (67b) that performs AC coupling between the drain line side of the potential monitoring unit and a reference potential.

6. The automatic driving system according to claim 5, wherein: The abnormality detection unit includes a current limiting resistor (64) between the drain line and the pulse generating unit, and the current limiting resistor limits the current flowing in the drain line to a set current value or less.

7. The automatic driving system according to claim 5, wherein: The abnormality detection unit includes a capacitor (67a) that performs AC coupling between the drain line and the pulse generating unit.

8. The automatic driving system according to claim 1, wherein: The abnormality detection unit includes a switch portion (63) that opens and closes between the drain line and the pulse generating portion. The abnormality determination unit closes the switch unit at the stop timing, and opens the switch unit at times other than the stop timing.

9. The automatic driving system according to any one of claims 1 to 8, wherein: The abnormality detection unit is detachably provided in the vehicle.

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