Patent Publication Number: US-2020290514-A1

Title: Driving assistance device, vehicle, and vehicle control device

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority to and the benefit of Japanese Patent Application No. 2019-048694 filed on Mar. 15, 2019, the entire disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a driving assistance device, a vehicle and a vehicle control device. 
     Description of the Related Art 
     A vehicle equipped with a periphery image provision system that includes a camera which photographs the periphery of a vehicle, and a display device that provides the photographed image to a vehicle occupant has been proposed. International Publication No. 2017/203970 discloses a vehicle in which a plurality of such periphery image provision systems are mounted. 
     In a case where there is a deterioration in the performance of a periphery image provision system, such as when a photographed image is not displayed appropriately on a display device or the like, it is desirable to notify the occurrence of such a situation to a vehicle occupant. However, a case can arise in which the periphery image provision system at which the deterioration in the performance has occurred cannot itself notify the vehicle occupant of the deterioration in the performance. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is, in the case of providing an image of the periphery of a vehicle to an occupant of the vehicle, to more reliably notify the vehicle occupant of a deterioration in the performance of a system. 
     According to an aspect of the present invention, there is provided a driving assistance device, comprising: a first periphery image provision unit configured to provide an image of a periphery of a vehicle to a vehicle occupant, and a second periphery image provision unit configured to provide an image of a periphery of the vehicle to a vehicle occupant; wherein: the first periphery image provision unit includes: a first photographing unit configured to photograph a periphery of the vehicle, a first display unit configured to display an image photographed by the first photographing unit, and a first control unit configured to control the first display unit; the second periphery image provision unit includes: a second photographing unit configured to photograph a periphery of the vehicle, a second display unit configured to display an image photographed by the second photographing unit, and a second control unit configured to control the second display unit; the first control unit: monitors a state of the second periphery image provision unit; and performs processing that, based on a monitoring result, notifies information relating to a deterioration in performance of the second periphery image provision unit to a vehicle occupant; and the second control unit: monitors a state of the first periphery image provision unit; and performs processing that, based on a monitoring result, notifies information relating to a deterioration in performance of the first periphery image provision unit to a vehicle occupant. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  and  FIG. 1B  are a plan view and a side view of a vehicle according to one embodiment of the present invention. 
         FIG. 2  is a view illustrating the inside of the cabin of the vehicle illustrated in  FIG. 1A  and  FIG. 1B . 
         FIG. 3  is a block diagram of a vehicle control device according to one embodiment of the present invention. 
         FIG. 4  is a flowchart illustrating an example of processing that is executed by the vehicle control device illustrated in  FIG. 3 . 
         FIG. 5A  is an explanatory diagram of a temperature range. 
         FIG. 5B  is a flowchart illustrating an example of processing that is executed by the vehicle control device illustrated in  FIG. 3 . 
         FIG. 6A  to  FIG. 6C  are views illustrating display examples of a display device and an indicator. 
         FIG. 7  is a flowchart illustrating another example of processing that is executed by the vehicle control device illustrated in  FIG. 3 . 
         FIG. 8A  and  FIG. 8B  are flowcharts illustrating a further example of processing that is executed by the vehicle control device illustrated in  FIG. 3 . 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, embodiments will be described in detail with reference to the attached drawings. Note that the following embodiments are not intended to limit the scope of the claimed invention, and limitation is not made an invention that requires all combinations of features described in the embodiments. Two or more of the multiple features described in the embodiments may be combined as appropriate. Furthermore, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted. 
     First Embodiment 
     &lt;Configuration of Vehicle&gt; 
       FIG. 1A  and  FIG. 1B  are a plan view and a side view of a vehicle  1  according to one embodiment of the present invention. Note that, in each figure, an arrow X indicates the front-and-rear direction of the vehicle  1 , and an arrow Y indicates the vehicle width direction of the vehicle  1 . An arrow Z indicates the vertical direction. 
     As one example, the vehicle  1  is a sedan-type four-wheeled passenger car. The vehicle  1  has two seats in a front row adjacent to a front window  5 , and two seats in a rear row, with the seat on the right side of the front row being the driver seat, and the seat on the left side being the front passenger seat. The vehicle  1  has a total of four doors that are adjacent to the respective seats, with a door  2 R being a door adjacent to the driver seat that is the right door on the front side. A door  2 L is a door adjacent to the front passenger seat, and is the left door on the front side. A drive unit  6  is provided at a front part of the vehicle  1 . The drive unit  6  includes a driving source that exerts a propulsive force of the vehicle  1 . The driving source is, for example, an engine (internal combustion engine) or a motor, or a combination of the engine (internal combustion engine) and the motor. The drive unit  6  includes a transmission such as an automatic transmission. 
     The vehicle  1  includes photographing apparatuses  3 ,  4 R and  4 L which photograph the periphery of the vehicle  1 . Each of the photographing apparatuses  3 ,  4 R and  4 L is, for example, a camera that includes an image pickup device such as an image sensor, and an optical system such as a lens. The photographing apparatus  3  photographs an image of a photographing range F at the front of the vehicle  1 . An image that was photographed by the photographing apparatus  3  is used, for example, to detect an obstacle in front of the vehicle  1  or to recognize road lane markings (for example, white lines). 
     The photographing apparatus  4 R is disposed at the front of the door  2 R, and a photographing range RR thereof is the rearward direction on the right side of the vehicle  1 . The photographing apparatus  4 L is disposed at the front of the door  2 L, and a photographing range LR thereof is the rearward direction on the left side of the vehicle  1 . 
       FIG. 2  is a view that schematically illustrates the inside of the cabin of the vehicle  1 , and in particular is a view that illustrates the area around a dashboard DB. A steering wheel W is provided in front of the driver seat, and an instrument panel  8  is provided in the dashboard DB on the front side of the steering wheel W. A display device  11  that displays map information and the like is provided at a center part in the vehicle width direction of the dashboard DB, and a shift lever  9  that accepts an operation to shift the transmission is disposed in the vicinity of the display device  11 . 
     A display device  7 R is disposed at a right end part of the dashboard DB, and a display device  7 L is disposed at a left end part of the dashboard DB. The display devices  7 R and  7 L are image display devices, and in the case of the present embodiment are liquid crystal display devices. An image that was photographed by the photographing apparatus  4 R is displayed on the display device  7 R, and an image that was photographed by the photographing apparatus  4 L is displayed on the display device  7 L. 
     The vehicle  1  of the present embodiment is a vehicle without side mirrors, and instead of side mirrors (door mirrors), the photographing apparatuses  4 R and  4 L and the display devices  7 R and  7 L constitute camera monitoring systems (CMSs) that are provided so as to allow a vehicle occupant (particularly the driver) to check the lateral rearward directions of the vehicle  1 . At least while the vehicle  1  is travelling, an image photographed by the photographing apparatus  4 R is continuously displayed on the display device  7 R, and an image photographed by the photographing apparatus  4 L is continuously displayed on the display device  7 L. 
     Indicators  10 R and  10 L are disposed on the dashboard DB. The indicators  10 R and  10 L are display devices which notify information relating to a deterioration in the performance of a CMS to a vehicle occupant. In the case of the present embodiment, the indicators  10 R and  10 L are each constituted by a light emitting device such as an LED, and as the form of notification of information relating to a deterioration in performance, in a case where a performance deterioration occurred or in a case where the possibility of a performance deterioration occurring has increased, the indicators  10 R and  10 L notify the vehicle occupant to such effect by activating (in this case, lighting up). 
     Note that, a configuration may be adopted in which the indicators  10 R and  10 L are only lit in a case where a deterioration in performance occurs. Further, the indicators  10 R and  10 L may each be an image display device such as a liquid crystal display device. Furthermore, a notification apparatus for notifying information to the vehicle occupant may be an audio output apparatus. 
     The indicator  10 R notifies information relating to a performance deterioration with respect to a CMS (a CMS  30 R in  FIG. 3 ) that includes the photographing apparatus  4 R and the display device  7 R to a vehicle occupant. Therefore, the indicator  10 R is arranged adjacent to a display screen  70 R of the display device  7 R. Although a position at which the indicator  10 R may be arranged is not limited to the aforementioned position, according to the arrangement in the present embodiment, it is easy for the vehicle occupant to understand that actuation of the indicator  10 R is a notification relating to the CMS  30 R. 
     The indicator  10 L notifies information relating to a performance deterioration with respect to a CMS (a CMS  30 L in  FIG. 3 ) that includes the photographing apparatus  4 L and the display device  7 L to a vehicle occupant. Therefore, the indicator  10 L is arranged adjacent to a display screen  70 L of the display device  7 L. Although a position at which the indicator  10 L may be arranged is not limited to the aforementioned position, according to the arrangement in the present embodiment, it is easy for the vehicle occupant to understand that actuation of the indicator  10 L is a notification relating to the CMS  30 L. 
       FIG. 3  is a block diagram illustrating a vehicle control device  20  which is a driving assistance device that is an on-board apparatus of the vehicle  1 , and in particular  FIG. 3  illustrates a configuration example relating to the CMSs. The CMS  30 L is a system that assists driving by photographing the photographing range LR and providing the photographed image to a vehicle occupant, and includes the photographing apparatus  4 L, the display device  7 L and an ECU (CMSECU)  21 L. The CMS  30 R is a system that photographs the photographing range RR and provides the photographed image to a vehicle occupant, and includes the photographing apparatus  4 R, the display device  7 R and an ECU (CMSECU)  21 R. 
     The ECU  21 L is a control unit that performs overall control of the CMS  30 L, and in particular performs control of the display device  7 L. Further, the ECU  21 L performs control of the indicator  10 R, and not the indicator  10 L. Similarly, the ECU  21 R is a control unit that performs overall control of the CMS  30 R, and in particular performs control of the display device  7 R, and also performs control of the indicator  10 L and not the indicator  10 R. Thus, with regard to the indicators  10 L and  10 R, by making the corresponding ECUs the opposite to the CMSs  30 L and  30 R, even if a performance deterioration occurs in one of the systems, it is possible to notify the performance deterioration to a vehicle occupant. 
     For example, in a case where a performance deterioration occurs in a part of the configuration of the CMS  30 L and a photographed image is no longer displayed, the ECU  21 R actuates the indicator  10 L so that the occurrence of the performance deterioration in the CMS  30 L can be notified to the vehicle occupant. Similarly, in a case where a performance deterioration occurs in a part of the configuration of the CMS  30 R and a photographed image is no longer displayed, the ECU  21 L actuates the indicator  10 R so that the occurrence of the performance deterioration in the CMS  30 R can be notified to the vehicle occupant. 
     The ECUs  21 L and  21 R each include a processor as typified by a CPU, a storage device such as a semiconductor memory, and an interface with an external device and the like. A program that the processor executes and data that the processor uses for processing and the like are stored in the storage device. Each of the ECUs  21 L and  21 R may include a plurality of processors, storage devices and interfaces and the like, and the processor may include a CPU and an image processing processor. The image processing processor may have a function that processes the signals of images photographed by the photographing apparatuses  4 L and  4 R and outputs display image signals to the display devices  7 L and  7 R. The ECUs  21 L and  21 R are communicably connected to each other through an in-vehicle network NT. 
     The display devices  7 L and  7 R include control circuits  71 L and  71 R, liquid crystal display panels  72 L and  72 R, and temperature sensors  73 L and  73 R, respectively. The control circuits  71 L and  71 R respectively include a processor as typified by a CPU, a storage device such as a semiconductor memory, an interface with an external device, and a drive circuit for the corresponding liquid crystal display panel  72 L or  72 R and the like. The control circuit  71 L performs driving control of the corresponding liquid crystal display panel  72 L and processing that sends a detection result of the temperature sensor  73 L to the corresponding ECU  21 L and the like. Similarly, the control circuit  71 R performs driving control of the corresponding liquid crystal display panel  72 R and processing that sends a detection result of the temperature sensor  73 R to the corresponding ECU  21 R and the like. The temperature sensor  73 L detects the temperature of the liquid crystal display panel  72 L. Similarly, the temperature sensor  73 R detects the temperature of the liquid crystal display panel  72 R. The temperature sensors  73 L and  73 R are, for example, thermistors. 
     A power supply circuit  22 L is connected to an on-board battery, and supplies driving power to the photographing apparatus  4 L and the ECU  21 L of the CMS  30 L and to the indicator  10 R. A power supply circuit  23 L is connected to an on-board battery, and supplies driving power to the display device  7 L of the CMS  30 L. A power supply circuit  22 R is connected to an on-board battery, and supplies driving power to the photographing apparatus  4 R and the ECU  21 R of the CMS  30 R and to the indicator  10 L. A power supply circuit  23 R is connected to an on-board battery, and supplies driving power to the display device  7 R of the CMS  30 R. 
     By providing separate power supply circuits for the set composed of the CMS  30 L and the indicator  10 R and for the set composed of the CMS  30 R and the indicator  10 L, respectively, even if a performance deterioration occurs at one of the power supply circuits, each component that receives a supply of power from the other power supply circuit can be actuated. 
     For example, in a case where the power supply circuits  22 L and  23 L can no longer supply the necessary power to each component of the CMS  30 L and the indicator  10 R, the aforementioned components will no longer operate. However, since the CMS  30 R and the indicator  10 L are supplied with power from the power supply circuits  22 R and  23 R, it is possible to actuate the indicator  10 L and thereby notify the vehicle occupant of a performance deterioration in the CMS  30 L. Similarly, in a case where the power supply circuit  22 R can no longer supply the necessary power, it is possible to actuate the indicator  10 R and thereby notify the vehicle occupant of a performance deterioration in the CMS  30 R. 
     Further, by providing separate power supply circuits for the display device  7 L and for the ECU  21 L and indicator  10 R, even if a performance deterioration occurs in the power supply circuit  23 L, it is possible for the ECU  21 L and the indicator  10 R to operate by means of power supplied by the power supply circuit  22 L. Similarly, by providing separate power supply circuits for the display device  7 R and for the ECU  21 R and indicator  10 L, even if a performance deterioration occurs in the power supply circuit  23 R, it is possible for the ECU  21 R and the indicator  10 L to operate by means of power supplied by the power supply circuit  22 R. 
     In the case of the present embodiment, the power supply circuit  22 L, the ECU  21 L, the ECU  21 R and the power supply circuit  22 R are mounted on a control board  20   a.  By mounting the main components of the control systems of the CMS  30 L and CMS  30 R on a common control board  20   a,  assembly of the main components of these control systems in the vehicle  1  as well as maintenance thereof can be simplified. 
     &lt;Example of Processing of Control Units&gt; 
     An example of processing which the ECU  21 L and the ECU  21 R execute will now be described referring to  FIG. 4  to  FIG. 5B , and  FIG. 6A  to  FIG. 6C . Here, processing for notifying information relating to a performance deterioration in the CMS  30 L and the CMS  30 R to a vehicle occupant will be described.  FIG. 4  and  FIG. 5B  illustrate processing which the ECU  21 L and the ECU  21 R repeatedly execute, respectively.  FIG. 4  illustrates processing in which the ECU  21 L and the ECU  21 R determine the state of the CMS to which they belong, i.e. the CMS  30 L and the CMS  30 R, respectively, and notify information relating to a performance deterioration that is based on the determination result to the vehicle occupant.  FIG. 5B  illustrates processing in which the ECU  21 L and the ECU  21 R monitor the state of the CMS to which they do not belong, i.e. the CMS  30 R and the CMS  30 L, respectively, and notify information relating to a performance deterioration that is based on the monitoring result to the vehicle occupant. 
     Factors for determining a performance deterioration in the CMS  30 L or the CMS  30 R in the present embodiment are broadly classified into three kinds, that is, factors for determining a deterioration in the performance of the display devices  7 L and  7 R, factors for determining a deterioration in the performance of the photographing apparatuses  4 L and  4 R, and factors for determining a deterioration in the performance of the ECUs  21 L and  21 R (or a deterioration in the performance of the power supply circuits  22 L,  23 L,  22 R and  23 R). However, the number of kinds of factors for determining a performance deterioration may be four or more, or may be only one kind or only two kinds among the aforementioned three kinds. 
     A deterioration in the performance of the display devices  7 L and  7 R that is supposed in the present embodiment relates to a deterioration in performance that is caused by the temperature of the liquid crystal display panels  72 L and  72 R. In general, when a liquid crystal display device is at a high temperature (for example, 80° C. or higher), a decrease in brightness or shortening of the life of the product may occur. Further, at a low temperature (for example, below freezing point), an afterimage may remain in some cases. In some cases, a photographed image may not be displayed clearly due to such temperature factors. The inside of the cabin of the vehicle  1  may become a high temperature during summer, and in cold districts the inside of the cabin may sometimes become a low temperature. 
     A deterioration in the performance of the photographing apparatuses  4 L and  4 R is, for example, a case where photographed image sticking occurs (the image pickup signal does not change). The vehicle occupant will experience a sense of incongruity if a photographed image does not change while the vehicle  1  is travelling. A deterioration in the performance of the ECUs  21 L and  21 R is, for example, a case where execution of a program stops. A deterioration in the performance of the power supply circuit  22 L,  23 L,  22 R or  23 R is, for example, a case where required power is not being output. 
     In the following description, to facilitate understanding, a situation is assumed in which the ECU  21 R executes the processing illustrated in  FIG. 4 , and the ECU  21 L executes the processing illustrated in  FIG. 5B , although the following description also applies in the opposite case.  FIG. 6A  to  FIG. 6C  illustrate display examples of the display screen  70 R of the display device  7 R and display examples of the indicator  10 R.  FIG. 6A  illustrates a state in which there is no performance deterioration in the CMS  30 R, and an image that is photographed by the photographing apparatus  4 R is displayed on the display screen  70 R. The indicator  10 R is in a non-notification state (is not lighting). 
     In  FIG. 4 , in S 1  the ECU  21 R acquires temperature information showing a temperature detection result of the temperature sensor  73 R through the control circuit  71 R. In S 2 , the ECU  21 R determines whether or not the temperature information acquired in S 1  belongs to an alert range. If the ECU  21 R determines that the temperature information belongs to the alert range, the ECU  21 R proceeds to S 3 , and if it is determined that the temperature information does not belong to the alert range, the ECU  21 R proceeds to S 5 . 
     The term “alert range” refers to a temperature range in which the vehicle occupant is to be notified that there is a possibility of the occurrence of a deterioration in the performance of the display devices  7 L and  7 R.  FIG. 5A  illustrates examples of ranges relating to a deterioration in the performance of the display devices  7 L and  7 R, which are classified into a normal range, an alert range, and a display stopping range. The normal range is a temperature range in which it is regarded that there is no performance deterioration caused by the temperature of the display devices  7 L and  7 R, and is the range from a temperature T 2  to a temperature T 3 . The alert range is a range in which it is possible that a performance deterioration caused by the temperature of the display devices  7 L and  7 R may occur, and is a range from a temperature T 1  to the temperature T 2  on the low temperature side, and a range from the temperature T 3  to a temperature T 4  on the high temperature side. The display stopping range is a temperature range in which it is regarded that a performance deterioration caused by the temperature of the display devices  7 L and  7 R has occurred or in which the product life will be noticeably shortened, and is a range of temperatures lower than the temperature T 1  on the low temperature side, and a range of temperatures higher than the temperature T 4  on the high temperature side. 
     Returning to  FIG. 4 , in S 3  the ECU  21 R sends information (performance deterioration information) indicating a performance deterioration in the CMS  30 R to the ECU  21 L through the in-vehicle network NT. In S 4 , the ECU  21 R displays an attention icon as information indicating a performance deterioration on the display device  7 R.  FIG. 6B  illustrates an example of the display of the display device  7 R. An attention icon IC is displayed on the display screen  70 R in a manner in which the attention icon IC is superimposed on a photographed image. By using the attention icon IC to notify the vehicle occupant, the vehicle occupant recognizes that there is a possibility that a deterioration in the performance of the display device  7 R is occurring. 
     Returning to  FIG. 4 , in S 5  the ECU  21 R determines whether or not the temperature information acquired in S 1  belongs to the display stopping range. If the ECU  21 R determines that the temperature information belongs to the display stopping range, the ECU  21 R proceeds to S 8 , and if the ECU  21 R determines that the temperature information does not belong to the display stopping range, the ECU  21 R proceeds to S 6 . In S 6 , the ECU  21 R makes a determination regarding the operation of the photographing apparatus  4 R. In this case, for example, the ECU  21 R checks whether or not the photographed image sticking that is described above is occurring. In S 7 , based on the result of the determination regarding operation of the photographing apparatus  4 R in S 6 , the ECU  21 R determines whether a deterioration in the performance of the photographing apparatus  4 R is occurring, and if the ECU  21 R determines that a performance deterioration is occurring, the ECU  21 R proceeds to S 8 , while if the ECU  21 R determines that there is no performance deterioration the ECU  21 R proceeds to S 10 . 
     In S 8 , the ECU  21 R sends information indicating a performance deterioration in the CMS  30 R to the ECU  21 L through the in-vehicle network NT. In S 9 , the ECU  21 R stops the display of a photographed image by the display device  7 R.  FIG. 6C  illustrates an example of the display of the display device  7 R. In this example, the display screen  70 R is blacked out. The vehicle occupant recognizes that a deterioration in the performance of the display device  7 R is occurring. 
     In S 10 , the ECU  21 R performs restoration processing. Here, in a case where the processing in S 3  and S 4  or in S 8  and S 9  was performed, the ECU  21 R performs processing to restore the display or the like to the original state thereof. Specifically, in order to show that there is not a deterioration in performance at neither the display device  7 R nor the photographing apparatus  4 R, the ECU  21 R sends information (performance maintained information) indicating that the performance of the CMS  30 R is being maintained to the ECU  21 L through the in-vehicle network NT. Further, the ECU  21 R performs an operation to stop the display of the attention icon IC that was displayed in S 4 , and to release the stopped state of the display of the photographed image that was stopped in S 9 . Thus, one round of processing ends. 
     Processing which the ECU  21 L performs to monitor the state of the CMS  30 R will now be described referring to  FIG. 5B . In S 11 , the ECU  21 L performs processing to confirm the communication state. In this case, the ECU  21 L performs communication with the ECU  21 R through the in-vehicle network NT and verifies whether or not a deterioration in performance is occurring at the ECU  21 R. For example, the ECU  21 L outputs a response request to the ECU  21 R, and in a case where there is no response, the ECU  21 L can determine that a deterioration in performance is occurring at the ECU  21 R due to a deterioration in the performance of the ECU  21 R itself or due to a power interruption at the power supply circuit  22 R. 
     In S 12 , the ECU  21 L determines whether or not a deterioration in performance is occurring at the ECU  21 R based on the result of the confirmation processing in S 11 , and if the ECU  21 L determines that a deterioration in performance is occurring, the ECU  21 L proceeds to S 14 , while if the ECU  21 L determines that there is no deterioration in performance, the ECU  21 L proceeds to S 13 . In S 13 , the ECU  21 L determines whether or not performance deterioration information was received from the ECU  21 R. If performance deterioration information was received, the ECU  21 L proceeds to S 14 , while if performance deterioration information was not received the ECU  21 L proceeds to S 15 . 
     In S 14 , the ECU  21 L performs processing to notify information relating to a performance deterioration in the CMS  30 R to the vehicle occupant. In the present embodiment, the ECU  21 L activates the indicator  10 R so that the indicator  10 R enters a notification state (a lighting state).  FIG. 6B  and  FIG. 6C  illustrate an operation example with respect to the indicator  10 R. In the example illustrated in  FIG. 6B  and  FIG. 6C , as a result of the indicator  10 R lighting, an exclamation mark is displayed.  FIG. 6B  corresponds to a situation in which, in the processing in S 3  and S 4  in  FIG. 4 , the ECU  21 R sends performance deterioration information, and the attention icon IC is displayed in a superimposed manner on the photographed image.  FIG. 6C  corresponds to a situation in which, in the processing in S 8  and S 9  in  FIG. 4 , the ECU  21 R sends performance deterioration information, and the attention icon IC is displayed in a superimposed manner on the photographed image. Although an example of a display that is caused by a deterioration in the performance of the ECU  21 R is not particularly illustrated in the drawings, some kind of image is displayed on the display screen  70 R or an image is not displayed thereon, and the indicator  10 R enters an operating state. In either case, by the indicator  10 R lighting, the fact that a performance deterioration is occurring in the CMS  30 R can be more reliably notified to the vehicle occupant. 
     In S 15  in  FIG. 5B , the ECU  21 L determines whether or not performance maintained information was received from the ECU  21 R. If performance maintained information was received, the ECU  21 L proceeds to S 16 . In S 16 , the ECU  21 L performs processing to end notification. Here, in a case where the indicator  10 R is operating, the ECU  21 L stops operation of the indicator  10 R to place the indicator  10 R in a non-notification state (not lighting). By this means, for example, in a case where the indicator  10 R operated because the temperature of the liquid crystal display panel  72 R was a temperature belonging to the alert range and thereafter the temperature returned to the normal range, operation of the indicator  10 R is stopped. 
     As described above, in the present embodiment, by the ECU  21 L monitoring the state of the CMS  30 R, and the ECU  21 R monitoring the state of the CMS  30 L, the occurrence of a deterioration in performance in the respective systems of the CMS  30 R and the CMS  30 L can be more reliably notified to the vehicle occupant. Further, because monitoring of the systems is performed only by means of communication between the ECU  21 L and the ECU  21 R, the only wiring required for monitoring the systems is the wiring of the in-vehicle network NT, and hence the convenience with respect to wiring is high. 
     Note that, although in the present embodiment a configuration is adopted in which after the indicators  10 L and  10 R are operated, it is possible to stop operation of the indicators  10 L and  10 R by executing S 16  in  FIG. 5B , a configuration may be adopted in which an operation to restart the drive unit  6  is required to stop operation of the indicators  10 L and  10 R. The same applies with respect to executing the processing in S 10  of  FIG. 4  to stop display of the attention icon IC that was displayed in S 4  or release the stopped state of the display that was stopped in S 9 . Alternatively, among the processing to stop display of the attention icon IC displayed in S 4  and the processing to release the stopped state of the display that was stopped in S 9  by executing S 10  of  FIG. 4 , a configuration may be adopted in which an operation to restart the drive unit  6  is required with respect to releasing the stopped state of the display that was stopped in S 9 . 
     Further, although in the present embodiment the temperature sensors  73 L and  73 R are used for detecting the states of the display devices  7 L and  7 R, a physical quantity for detecting the states of the display devices  7 L and  7 R is not limited to a temperature. For example, a performance deterioration may be determined by another physical quantity such as the current or voltage of the liquid crystal display panels  72 L and  72 R. Further, communication between the ECUs  21 L and  21 R and the corresponding control circuits  71 L and  71 R may be used to detect the states of the display devices  7 L and  7 R. For example, a response request may be sent from the ECU  21 L to the control circuit  71 L, and if a response is not received the ECU  21 L may determine that a deterioration in performance has occurred at the display device  7 L. 
     Second Embodiment 
     Although in the first embodiment, a configuration is adopted in which processing is performed that, as information based on detection results of the temperature sensors  73 L and  73 R, sends, from one ECU to the other ECU (S 3 , S 8 ), performance deterioration information which is information after determining a performance deterioration, a configuration may also be adopted in which processing is performed that sends temperature information from one ECU to the other ECU, and a determination regarding whether to actuate the indicators  10 L and  10 R is made on the other ECU side.  FIG. 7 ,  FIG. 8A  and  FIG. 8B  are flowcharts illustrating processing examples that take the place of the processing examples in  FIG. 4  and  FIG. 5B . Hereunder, processing that is different from the processing examples in  FIG. 4  and  FIG. 5B  is described, and a description regarding processing that is the same as in the processing examples in  FIG. 4  and  FIG. 5B  is omitted. Further, in the following description, similarly to the first embodiment, to facilitate understanding, a situation is assumed in which the ECU  21 R executes the processing illustrated in  FIG. 7 , and the ECU  21 L executes the processing illustrated in  FIG. 8A  and  FIG. 8B , although the following description also applies in the opposite case. 
     In the processing example illustrated in  FIG. 7 , in S 1 ′ that is after S 1 , the ECU  21 R sends the temperature information which was acquired in S 1  to the ECU  21 L through the in-vehicle network NT. The processing in S 3  in  FIG. 4  is not performed in the present embodiment. In S 5 , if the ECU  21 R determined that the temperature information acquired in S 1  belongs to the display stopping range, the ECU  21 R proceeds to S 9 ′ and performs display stopping processing that is the same as in S 9  in  FIG. 4 . Thereafter, the ECU  21 R ends one unit of processing. Thus, in the present embodiment the ECU  21 R does not send performance deterioration information relating to the display device  7 R to the ECU  21 L. 
     Monitoring processing performed by the ECU  21 L in the present embodiment will now be described referring to  FIG. 8A  and  FIG. 8B . In S 12 , if the ECU  21 L determines that there is no performance deterioration at the ECU  21 R, the ECU  21 L proceeds to S 21 . In S 21 , the ECU  21 L determines whether or not temperature information was received from the ECU  21 R. If temperature information was received, the ECU  21 L proceeds to S 22 , and if temperature information was not received, the ECU  21 L proceeds to S 25 . In S 22 , the ECU  21 L determines whether or not the received temperature information is outside the normal range (whether or not the received temperature information belongs to the alert range or the display stopping range). If it is determined that the received temperature information is outside the normal range the ECU  21 L proceeds to S 14 , and if it is determined that the received temperature information belongs to the normal range the ECU  21 L proceeds to S 23 . 
     In S 23 , based on the performance deterioration information that was already received from the ECU  21 R, the ECU  21 L determines whether or not a deterioration in the performance of the photographing apparatus  4 R is currently occurring, and if the ECU  21 L determines that a performance deterioration is occurring the ECU  21 L proceeds to S 25 , while if the ECU  21 L determines that a performance deterioration is not occurring, the ECU  21 L proceeds to S 24 . In S 24 , in a case where the indicator  10 R is in a notification state, the ECU  21 L ends the operation of the indicator  10 R to thereby place the indicator  10 R in a non-notification state. 
     In S 25 , the ECU  21 L determines whether or not performance deterioration information for the photographing apparatus  4 R was received from the ECU  21 R. If performance deterioration information was received, the ECU  21 L proceeds to S 14 , and if performance deterioration information was not received, the ECU  21 L proceeds to S 26 . In S 26 , the ECU  21 L determines whether or not performance maintained information for the photographing apparatus  4 R was received from the ECU  21 R. If performance maintained information was received, the ECU  21 L proceeds to S 27 , and if performance maintained information was not received, the ECU  21 L ends the processing. In S 27 , the ECU  21 L determines whether or not the most recent temperature information received from the ECU  21 R is outside the normal range (whether or not the temperature information belongs to the alert range or display stopping range). If it is determined that the temperature information is outside the normal range, the ECU  21 L ends the processing, while if it is determined that the temperature information belongs to the normal range the ECU  21 L proceeds to S 28 . In S 28 , if the indicator  10 R is in a notification state, the ECU  21 L ends the operation of the indicator  10 R to thereby place the indicator  10 R in a non-notification state. 
     Thus, according to the present embodiment, in the monitoring processing shown in  FIG. 8A  and  FIG. 8B , based on temperature information of the display device  7 R of the CMS  30 R that is the monitoring object, the ECU  21 L can determine that there is a deterioration in the performance of the display device  7 R, and can actuate the indicator  10 R. 
     Other Embodiments 
     Although in the embodiments described above, the vehicle  1  is a vehicle without side mirrors, the present invention is also applicable to a vehicle with side mirrors. Further, although the ECUs  21 L and  21 R of the CMS  30 L and CMS  30 R that provide images of the lateral rearward directions of the vehicle  1  are configured so as to monitor each other&#39;s systems, the present invention is not limited thereto. For example, a configuration may be adopted in which the respective ECUs of a system that provides an image of the front of the vehicle  1  and a system that provides an image of the rear of the vehicle  1  monitor each other&#39;s systems. Further, the respective ECUs of three or more systems may monitor each other&#39;s systems. 
     Summary of Embodiments 
     The above embodiments disclose at least the following driving assistance device, vehicle and vehicle control device. 
     1. A driving assistance device (for example,  20 ) of the aforementioned embodiments is a driving assistance device that includes: 
     a first periphery image provision unit (for example,  30 L) configured to provide an image of a periphery of a vehicle to a vehicle occupant, and 
     a second periphery image provision unit (for example,  30 R) configured to provide an image of a periphery of the vehicle to a vehicle occupant; 
     wherein: 
     the first periphery image provision unit includes: 
     a first photographing unit (for example,  4 L) configured to photograph a periphery of the vehicle, 
     a first display unit (for example,  7 L) configured to display an image photographed by the first photographing unit, and 
     a first control unit (for example,  21 L) configured to control the first display unit; 
     the second periphery image provision unit includes: 
     a second photographing unit (for example,  4 R) configured to photograph a periphery of the vehicle, 
     a second display unit (for example,  7 R) configured to display an image photographed by the second photographing unit, and 
     a second control unit (for example,  21 R) configured to control the second display unit; 
     the first control unit: 
     monitors a state of the second periphery image provision unit, and performs processing that, based on a monitoring result, notifies information relating to a deterioration in performance of the second periphery image provision unit to a vehicle occupant (for example, S 14 ); and 
     the second control unit: 
     monitors a state of the first periphery image provision unit, and performs processing that, based on a monitoring result, notifies information relating to a deterioration in performance of the first periphery image provision unit to a vehicle occupant (for example, S 14 ). 
     According to this embodiment, when providing images of the periphery of a vehicle to a vehicle occupant, a deterioration in the performance of a system can be more reliably notified to a vehicle occupant. 
     2. In the aforementioned embodiment: 
     the first control unit monitors a state of the second periphery image provision unit by means of communication with the second control unit (for example,  FIG. 5B ,  FIG. 8A  and  FIG. 8B ), and 
     the second control unit monitors a state of the first periphery image provision unit by means of communication with the first control unit (for example,  FIG. 5B ,  FIG. 8A  and  FIG. 8B ). 
     According to this embodiment, it is possible for each of the control units to monitor each other&#39;s system by means of only communication between each of the control units, and thus convenience with respect to wiring and the like can be achieved. 
     3. In the aforementioned embodiment: 
     the first periphery image provision unit includes a first detection unit (for example,  73 L) configured to detect a state of the first display unit; 
     the second periphery image provision unit includes a second detection unit (for example,  73 R) configured to detect a state of the second display unit; 
     the first control unit sends information that is based on a detection result of the first detection unit (for example, performance deterioration information or temperature information) to the second control unit, and the second control unit monitors a state of the first display unit by means of the information that is received (for example,  FIG. 5B ,  FIG. 8A  and  FIG. 8B ), and 
     the second control unit sends information that is based on a detection result of the second detection unit (for example, performance deterioration information or temperature information) to the first control unit, and the first control unit monitors a state of the second display unit by means of the information that is received (for example,  FIG. 5B ,  FIG. 8A  and  FIG. 8B ). 
     According to this embodiment, it is possible for each of the control units to monitor each other&#39;s display unit by means of only communication between each of the control units, and thus convenience with respect to wiring and the like can be achieved. 
     4. The aforementioned embodiment further includes: 
     a first notification unit, and 
     a second notification unit, wherein: 
     the first control unit (for example,  21 L) notifies information relating to a deterioration in performance of the second periphery image provision unit (for example,  30 R) to a vehicle occupant by means of the first notification unit (for example,  10 R), and 
     the second control unit (for example,  21 R) notifies information relating to a deterioration in performance of the first periphery image provision unit (for example,  30 L) to a vehicle occupant by means of the second notification unit (for example,  10 L). 
     According to this embodiment, even in a case where there is a deterioration in the performance of the respective display units, a deterioration in the performance of the system can be notified to a vehicle occupant by the respective notification units. 
     5. In the aforementioned embodiment: 
     the first notification unit is a first indicator (for example,  10 R) that is disposed adjacent to a display screen (for example,  70 R) of the second display unit (for example,  7 R), and 
     the second notification unit is a second indicator (for example,  10 L) that is disposed adjacent to a display screen (for example,  70 L) of the first display unit (for example,  7 L). 
     According to this embodiment, a system in which a performance deterioration is occurring can be notified to a vehicle occupant in a more easily understandable manner. 
     6. In the aforementioned embodiment: 
     the first control unit monitors a state of the first display unit, and displays information (for example, IC) relating to a deterioration in performance of the first display unit on the first display unit based on a monitoring result; 
     the second control unit actuates the second indicator based on a monitoring result regarding a state of the first display unit; 
     the second control unit monitors a state of the second display unit, and displays information (for example, IC) relating to a deterioration in performance of the second display unit on the second display unit based on a monitoring result; and 
     the first control unit actuates the first indicator based on a monitoring result regarding a state of the second display unit. 
     According to this embodiment, because the respective display units and the respective indicators are controlled by different control units, even if a deterioration in performance occurs in either of the systems, it is possible to notify the deterioration in performance to the vehicle occupant. 
     7. The aforementioned embodiment further includes: 
     a first power supply circuit (for example,  22 L) configured to supply electric power to the first photographing unit, the first control unit and the first notification unit; and 
     a second power supply circuit (for example,  22 R) configured to supply electric power to the second photographing unit, the second control unit and the second notification unit. 
     According to this embodiment, even if a power interruption occurs in one of the systems, electric power can be supplied to the other system, and thus notification of a deterioration in the performance of a system is possible. 
     8. In the aforementioned embodiment: 
     the first display unit and the second display unit are each a liquid crystal display device; and 
     the first detection unit and the second detection unit are each a temperature sensor. 
     According to this embodiment, a deterioration in the performance of the respective display units that is caused by the temperature can be notified. 
     9. In the aforementioned embodiment: 
     the vehicle is a vehicle without side mirrors; 
     the first photographing unit photographs a rearward direction on a left side (for example, LR) of the vehicle; 
     the first display unit is disposed on a left side of the vehicle; 
     the second photographing unit photographs a rearward direction on a right side (for example, RR) of the vehicle; and 
     the second display unit is disposed on a right side of the vehicle. 
     According to this embodiment, in a vehicle without side mirrors, a deterioration in the performance of a system can be more reliably notified to a vehicle occupant. 
     10. A vehicle (for example,  1 ) of the aforementioned embodiment includes: 
     the aforementioned driving assistance device (for example,  20 ). 
     According to this embodiment, when providing images of the periphery of a vehicle to a vehicle occupant, a deterioration in the performance of a system can be more reliably notified to the vehicle occupant. 
     11. The vehicle control device (for example,  20 ) of the aforementioned embodiment includes: 
     a first control unit (for example,  21 L) configured to control a first display unit (for example,  4 L) configured to display an image of a periphery of a vehicle; and 
     a second control unit (for example,  21 R) configured to control a second display unit (for example,  4 R) configured to display an image of a periphery of the vehicle; wherein: 
     the first control unit: 
     monitors a state of the second display unit, and performs processing (for example, S 14 ) to notify information relating to a deterioration in performance of the second display unit to a vehicle occupant based on a monitoring result; and 
     the second control unit: 
     monitors a state of the first display unit and performs processing (for example, S 14 ) to notify information relating to a deterioration in performance of the first display unit to a vehicle occupant based on a monitoring result. 
     According to this embodiment, when providing images of the periphery of a vehicle to a vehicle occupant, a deterioration in the performance of a system can be more reliably notified to the vehicle occupant. 
     The invention is not limited to the foregoing embodiments, and various variations/changes are possible within the spirit of the invention.