Patent ID: 12197963

DESCRIPTION OF EMBODIMENTS

To date, in association with increase in the number of vehicles manufactured as EVs (Electric Vehicles), increase in the number of sensors and actuators due to introduction of safe driving support systems into vehicles, and the like, the number of electronic control units (ECUs) mounted on a vehicle is increased, and an on-vehicle network is also becoming complicated. In such a complicated on-vehicle network, a plurality of ECUs transmit/receive data with one another, thereby controlling the vehicle.

In addition, technologies for managing resources of each ECU have been developed.

Problems to be Solved by the Present Disclosure

In the future, the operation rate of each ECU will be highly likely to be increased due to prevalence of shared cars, development of automated driving technology, and the like, and there is a demand for a technology that enables the usable time period of each ECU to be longer.

The present disclosure has been made in order to solve the above problem. An object of the present disclosure is to provide an on-vehicle control device, a control system, a control method, and a control program that enable the usable time period of each function unit mounted on a vehicle to be longer.

Effects of the Present Disclosure

According to the present disclosure, the usable time period of each function unit mounted on a vehicle can be made longer.

Description of Embodiment of the Present Disclosure

First, contents of embodiments of the present disclosure are listed and described.

(1) An on-vehicle control device according to an embodiment of the present disclosure includes: an acquisition unit configured to acquire a plurality of pieces of wear information regarding a degree of wear of each of a plurality of function units mounted on a vehicle; a selection unit configured to select, on the basis of each piece of the wear information acquired by the acquisition unit, from the plurality of function units, one or a plurality of the function units to be caused to perform a target process that should be performed by one or a plurality of the function units among the plurality of function units; and a control unit configured to perform a control of causing the one or plurality of the function units selected by the selection unit to perform the target process.

With this configuration, for example, the target process that should be performed by one or a plurality of function units having a high degree of wear can be distributed to another one or plurality of function units. Thus, increase in the degree of wear of each function unit having a high degree of wear can be suppressed. Therefore, the usable time period of each function unit mounted on the vehicle can be made longer.

(2) Preferably, as the one or plurality of the function units to be caused to perform the target process, the selection unit selects at least one function unit that is different from the one or plurality of the function units that should perform the target process.

With this configuration, for example, the target process that should be performed by a function unit having a high degree of wear can be caused to be performed by another function unit having a lower degree of wear.

(3) Preferably, the wear information includes information regarding heat of the function unit.

With the configuration in which the function unit is selected by using the information regarding heat that could significantly influence the wear of the function unit, the degree of wear of each function unit can be more accurately grasped, and more appropriate selection can be performed.

(4) Preferably, the wear information includes information regarding the number of times of rewriting of a memory included in the function unit.

With this configuration, since the function unit is selected by using the information regarding a memory that is easily worn among electronic components of the function unit, the degree of wear of each function unit can be more accurately grasped, and more appropriate selection can be performed.

(5) Preferably, the control unit further performs a control of reducing processing load of the one or plurality of the function units selected by the selection unit.

With this configuration, for example, the processing load of each selected function unit can be reduced. Thus, increase in the degree of wear of the function unit to which the target process is distributed can be suppressed.

(6) Preferably, the control unit changes a communication frequency of the function unit, as the control of reducing the processing load.

With this configuration, for example, by setting the communication frequency of the selected function unit so as to be reduced, it is possible to reduce the processing load of the function unit.

(7) Preferably, when no function unit is selected by the selection unit, the control unit performs a control of reducing processing load of the function unit that performs the target process.

With this configuration, even when there is no appropriate function unit to which the target process is distributed, increase in the degree of wear of the function unit that performs the target process can be suppressed.

(8) Preferably, the degree of wear is a proportion of an actual use time period in a predetermined period relative to a usable time period of the function unit, or a proportion of an actual number of times of rewriting in a predetermined period relative to a rewritable number of times of a memory included in the function unit. The wear information is information regarding history of temperature of the function unit, or information regarding the rewritable number of times of the memory. The temperature is temperature influenced by both of ambient temperature of the function unit and generated heat of the function unit. The generated heat of the function unit includes heat generated due to operation of various resources in the function unit, heat generated due to turning on/off of a power supply of the function unit, and heat generated due to occurrence of a ripple current.

With this configuration, since the function unit is selected by using information regarding heat that could significantly influence wear of the function unit or regarding a memory that is easily worn among electronic components of the function unit, the degree of wear of each function unit can be more accurately grasped, and a more appropriate function unit can be selected.

(9) A control system according to an embodiment of the present disclosure includes a management device and an on-vehicle control device. With respect to a plurality of vehicles, the management device: acquires a plurality of pieces of wear information regarding a degree of wear of each of a plurality of function units mounted on each vehicle; on the basis of the acquired each piece of the wear information, estimates a degree of wear of one or a plurality of the function units in the vehicle on which the on-vehicle control device is mounted; and transmits estimation information indicating an estimation result, to the on-vehicle control device. The on-vehicle control device: receives the estimation information transmitted from the management device; on the basis of the received estimation information, selects, from the plurality of function units in the vehicle on which the on-vehicle control device is mounted, one or a plurality of the function units to be caused to perform a target process that should be performed by one or a plurality of the function units among the plurality of function units; and performs a control of causing the selected one or plurality of the function units to perform the target process.

With this configuration, for example, the target process that should be performed by one or a plurality of function units having a high degree of wear can be distributed to another one or plurality of function units. Thus, increase in the degree of wear of each function unit having a high degree of wear can be suppressed.

With the configuration in which the management device estimates a degree of wear of each function unit, for example, a more accurate degree of wear can be calculated in the vehicle by using both of the degree of wear estimated by the management device and the degree of wear calculated in the vehicle. Therefore, the usable time period of each function unit mounted on the vehicle can be made longer.

(10) Preferably, the control system further comprises a dealer-side server configured to hold failure information regarding failures of a plurality of the function units. The dealer-side server transmits the failure information to the management device. On the basis of the acquired each piece of the wear information and the failure information received from the dealer-side server, the management device estimates the degree of wear of the one or plurality of the function units.

With the configuration in which the management device estimates a degree of wear of each function unit on the basis of the wear information and the failure information, a more accurate degree of wear can be calculated.

(11) A control method according to an embodiment of the present disclosure is to be performed in an on-vehicle control device. The control method includes the steps of: acquiring a plurality of pieces of wear information regarding a degree of wear of each of a plurality of function units mounted on a vehicle; on the basis of the acquired each piece of the wear information, selecting, from the plurality of function units, one or a plurality of the function units to be caused to perform a target process that should be performed by one or a plurality of the function units among the plurality of function units; and performing a control of causing the selected one or plurality of the function units to perform the target process.

With this method, for example, the target process that should be performed by one or a plurality of function units having a high degree of wear can be distributed to another one or plurality of function units. Thus, increase in the degree of wear of each function unit having a high degree of wear can be suppressed. Therefore, the usable time period of each function unit mounted on the vehicle can be made longer.

(12) A control method according to an embodiment of the present disclosure is to be performed in a control system including a management device and an on-vehicle control device. The control method includes the steps of: with respect to a plurality of vehicles, acquiring, performed by the management device, a plurality of pieces of wear information regarding a degree of wear of each of a plurality of function units mounted on each vehicle; on the basis of the acquired each piece of the wear information, estimating, performed by the management device, a degree of wear of one or a plurality of the function units in the vehicle on which the on-vehicle control device is mounted, and transmitting, performed by the management device, estimation information indicating an estimation result to the on-vehicle control device; receiving, performed by the on-vehicle control device, the estimation information transmitted from the management device, and selecting on the basis of the received estimation information, performed by the on-vehicle control device, from the plurality of function units in the vehicle on which the on-vehicle control device is mounted, one or a plurality of the function units to be caused to perform a target process that should be performed by one or a plurality of the function units among the plurality of function units; and performing, by the on-vehicle control device, a control of causing the selected one or plurality of the function units to perform the target process.

With this method, for example, the target process that should be performed by one or a plurality of function units having a high degree of wear can be distributed to another one or plurality of function units. Thus, increase in the degree of wear of each function unit having a high degree of wear can be suppressed.

With the method in which the management device estimates a degree of wear of each function unit, for example, a more accurate degree of wear can be calculated in the vehicle by using both of the degree of wear estimated by the management device and the degree of wear calculated in the vehicle. Therefore, the usable time period of each function unit mounted on the vehicle can be made longer.

(13) A control program according to an embodiment of the present disclosure is to be used in an on-vehicle control device. The control program causes a computer to function as: an acquisition unit configured to acquire a plurality of pieces of wear information regarding a degree of wear of each of a plurality of function units mounted on a vehicle; a selection unit configured to select, on the basis of each piece of the wear information acquired by the acquisition unit, from the plurality of function units, one or a plurality of the function units to be caused to perform a target process that should be performed by one or a plurality of the function units among the plurality of function units; and a control unit configured to perform a control of causing the one or plurality of the function units selected by the selection unit to perform the target process.

With this configuration, for example, the target process that should be performed by one or a plurality of function units having a high degree of wear can be distributed to another one or plurality of function units. Thus, increase in the degree of wear of each function unit having a high degree of wear can be suppressed. Therefore, the usable time period of each function unit mounted on the vehicle can be made longer.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference signs, and descriptions thereof are not repeated. At least some parts of the embodiments described below can be combined together as desired.

First Embodiment

Configuration and Basic Operation

On-Vehicle Communication System

FIG.1shows a configuration of an on-vehicle communication system according to a first embodiment of the present disclosure.

With referenceFIG.1, an on-vehicle communication system301includes: a management ECU (Electronic Control unit) (on-vehicle control device)101mounted on a vehicle10; and a plurality of ECUs (function units)111mounted on the vehicle10. Hereinafter, the plurality of ECUs111in the vehicle10will also be referred to as an “ECU group”. The plurality of ECUs111forming the ECU group (function unit group) will also be referred to as “each ECU111”.

For example, the ECU group includes an extra-vehicular communication device111a, an entertainment-related device111b, a travel control device111c, a camera111d, an object detection sensor111e, a temperature sensor111f, a battery state monitoring sensor111g, an automated driving ECU111h, and the like.

Each ECU111is connected to the management ECU101via a CAN bus according to the CAN (Controller Area Network) (registered trademark) standard, or an Ethernet (registered trademark) cable, for example. At least one ECU111in the ECU group may perform wireless communication with the management ECU101.

Each ECU111performs various processes in accordance with instructions from the management ECU101, and transmits result information indicating the result of each process, to the management ECU101.

The extra-vehicular communication device111acan perform wireless communication with a server or the like outside the vehicle10, via a wireless base station device.

The entertainment-related device111bcontrols apparatuses for providing entertainment services, specifically, a display, audio equipment, and the like.

The travel control device111cis an ECU for controlling traveling of the vehicle10, and is, for example, an engine control device, an AT (Automatic Transmission) control device, an HEV (Hybrid Electric Vehicle) control device, a brake control device, a chassis control device, a steering control device, an instrument indication control device, or the like.

The camera111dis an imaging device that takes an image of surroundings of the vehicle10.

The object detection sensor111eis a radar device using millimeter waves, for example, and detects objects such as a pedestrian and a vehicle around the vehicle10. The object detection sensor111eincludes a LiDAR (Light Detection and Ranging) used in automated driving, for example.

The temperature sensor111fdetects interior and exterior temperatures of the vehicle10, for example.

The battery state monitoring sensor111gmonitors the state of charge (SOC) and the state of health (SOH) of a battery mounted on the vehicle10, for example.

The automated driving ECU111hacquires, via the management ECU101, a detection result by the object detection sensor111e, and performs control related to automated driving of the vehicle10on the basis of the acquired detection result, for example.

Each ECU111transmits, to the management ECU101, wear information regarding the degree of wear of the ECU111, in a set transmission cycle or non-periodically. The wear information includes at least one of: information regarding heat of the ECU111; and information regarding the number of times of rewriting R of a memory such as a flash memory included in the ECU111, for example.

The information regarding heat of the ECU111may be information regarding heat of the ECU111itself, or may be information regarding heat around the ECU111. The information regarding heat around the ECU111is, for example, information indicating the temperature measured by a temperature sensor provided in the vicinity of the ECU111.

Each ECU111transmits, to the management ECU101in a set transmission cycle or non-periodically, resource state information indicating the state of resources of the ECU111, specifically, the use rate of resources such as a CPU (Central Processing Unit) and a memory.

The management ECU101manages the ECU group. More specifically, on the basis of the wear information transmitted from each ECU111, the management ECU101calculates the degree of wear of the corresponding ECU111. Then, on the basis of the calculated degree of wear of each ECU111and the resource state information transmitted from each ECU111, the management ECU101causes a process to be distributed among a plurality of ECUs111.

For example, the management ECU101assigns at least part of a target process that should be performed by one or a plurality of ECUs111having a high degree of wear, to another ECU111having a low degree of wear. Accordingly, various resources can be effectively utilized, and the usable time period (hereinafter, also referred to as “life”) of each ECU111can be made longer.

The management ECU101may assign the entirety of the target process performed by a certain ECU111, to another ECU111. Alternatively, the management ECU101may assign part of the target process, e.g., 50% of the target process, to another ECU111, and may cause the certain ECU111to perform the remaining 50%.

Instead of the management ECU101, at least one ECU111in the ECU group may manage the ECU group including the at least one ECU111.

Management ECU

FIG.2shows a configuration of the management ECU according to the first embodiment of the present disclosure.

With reference toFIG.2, the management ECU101includes a communication unit (acquisition unit)21, a selection unit22, a storage unit23, and a control unit24.

The communication unit21transmits/receives information to/from each ECU111. The communication unit21relays communication between ECUs111. The communication unit21outputs, to the selection unit22, wear information, result information, and resource state information which have been transmitted from each ECU111.

The selection unit22stores, into the storage unit23, the wear information, the result information, and the resource state information which have been received from the communication unit21. The selection unit22calculates a degree of wear of each ECU111on the basis of the corresponding wear information stored in the storage unit23, and confirms whether or not there is any ECU111having a high degree of wear.

The degree of wear is, for example, the proportion of an actual use time period in a predetermined period relative to a usable time period. The usable time period of each ECU111is obtained through, for example, a reliability test performed by a manufacturer.

When there is one or a plurality of ECUs111having a high degree of wear, the selection unit22performs a selection process of selecting, from the ECU group, one or a plurality of other ECUs111to be caused to perform at least part of a target process that should be performed by the one or plurality of ECUs111having the high degree of wear, on the basis of the degree of wear of each ECU111and the corresponding resource state information stored in the storage unit23.

For example, as one or a plurality of ECUs111to be caused to perform a target process, the selection unit22selects at least one function unit ECU111different from the one or plurality of ECUs111that should perform the target process.

The target process may be a process that should be performed by one ECU111, may be a process that should be performed by a plurality of ECUs111in cooperation, or may be a plurality of processes that should be respectively performed by a plurality of ECUs111. Hereinafter, an ECU111that substitutively performs the target process will also be referred to as a “substitute ECU”.

More specifically, for example, as the substitute ECU that substitutively performs a target process that should be performed by one ECU111i, the selection unit22may select another ECU111j, or may select the ECU111iand another ECU111k. For example, as the substitute ECU that substitutively performs a target process that should be performed by an ECU111mand an ECU111nin cooperation, the selection unit22may select one ECU111p, may select an ECU111qand an ECU111r, may select the ECU111mand an ECU111s, or may select the ECU111m, the ECU111n, and an ECU111t.

The selection unit22outputs, to the control unit24, selection result information indicating the selected one or plurality of substitute ECUs111and the content of the target process.

Upon receiving the selection result information from the selection unit22, the control unit24performs, on the basis of the selection result information, a substitution control for causing the one or plurality of substitute ECUs111selected by the selection unit22to perform the target process. More specifically, as the substitution control, the control unit24transmits a processing order indicating the target process, to each substitute ECU111via the communication unit21.

Each substitute ECU111receives the processing order transmitted from the management ECU101, performs the target process in accordance with the processing order, and transmits result information indicating an obtained result, to the management ECU101.

The control unit24receives, via the communication unit21, the result information transmitted from each substitute ECU111, and aggregates the result indicated by each received piece of the result information. In the following, details of a calculation process of the degree of wear performed by the selection unit22, and details of the selection process performed by the selection unit22and the substitution control performed by the control unit24are described.

Details of Calculation Process of Degree of Wear

(a-1) Example 1

Here, it is assumed that the wear information is information regarding heat of an ECU111itself, specifically, information regarding a history of temperature of the ECU111. For example, each ECU111: has a thermometer that measures the temperature of the ECU111; attaches a time stamp to wear information indicating a measurement result obtained by the thermometer; and transmits the wear information together with result information and resource state information, to the management ECU101.

The temperature indicated by the wear information is, for example, a temperature that is influenced by both of the ambient temperature of the ECU111and generated heat of the ECU111. The generated heat of the ECU111includes: heat generated due to operation of various resources; heat generated due to turning on/off a power supply of the ECU111; heat generated due to occurrence of a ripple current; and the like.

The storage unit23has stored therein life information indicating the life of each ECU111, for example. For each ECU111, the selection unit22calculates the proportion of an actual use time period relative to the life, on the basis of the corresponding wear information received via the communication unit21from the ECU111and the life information stored in the storage unit23.

Specifically, using an empirical rule such as 10° C. half-life, the selection unit22calculates a degree of wear in a predetermined period of each ECU111. The predetermined period is one minute, one hour, one day, one week, one month, or one year, for example.

For example, it is assumed that, in the life information, the life of a certain ECU111when used at 50° C. is 10000 hours. In addition, it is assumed that the predetermined period is one year. In this case, the selection unit22calculates a use time period in one year of the ECU111, thereby calculating the degree of wear of the ECU111.

More specifically, it is assumed that, for three months from March to May, the ECU111was used at an average temperature of 50° C. for 50 hours every month. In this case, the selection unit22grasps the use status of the ECU111in the three months on the basis of a plurality of pieces of wear information from the ECU111, and calculates a use time period of the ECU111in the three months as 150 hours (=50×3).

Further, it is assumed that, for three months from June to August, the ECU111was used at an average temperature of 80° C. for 50 hours every month. In this case, the selection unit22grasps the use status of the ECU111in the three months on the basis of a plurality of pieces of wear information from the ECU111, and calculates a use time period of the ECU111in the three months on the assumption that the ECU111was used at 50° C., as 1200 hours (=50×2{circumflex over ( )}{(80−50)/10}×3).

Further, it is assumed that, for three months from September to November, the ECU111was used at an average temperature of 60° C. for 50 hours every month. In this case, the selection unit22grasps the use status of the ECU111in the three months on the basis of a plurality of pieces of wear information from the ECU111, and calculates a use time period of the ECU111in the three months on the assumption that the ECU111was used at 50° C., as 300 hours (=50×2{circumflex over ( )}{(60−50)/10}×3).

Further, it is assumed that, for three months from December to February, the ECU111was used at an average temperature of 40° C. for 50 hours every month. In this case, the selection unit22grasps the use status of the ECU111in the three months on the basis of a plurality of pieces of wear information from the ECU111, and calculates a use time period of the ECU111in the three months on the assumption that the ECU111was used at 50° C., as 75 hours (=50×2{circumflex over ( )}{(40−50)/10}×3).

Then, the selection unit22calculates a use time period in one year of the ECU111as 1725 hours (=150+1200+300+75), and calculates the degree of wear of the ECU111as 17.25% (=1725/10000).

In a non-energization period of the on-vehicle communication system301, transmission of wear information from each ECU111to the management ECU101is not performed. Thus, the selection unit22interpolates the degree of wear of the ECU111in the non-energization period, on the basis of a plurality of pieces of wear information received in an energization period.

FIG.3is a graph for describing an interpolation process performed by the selection unit in the management ECU according to the first embodiment of the present disclosure. In the graph shown inFIG.3, the vertical axis represents temperature (° C.) and the horizontal axis represents time.

With reference toFIG.3, the selection unit22calculates the temperature of the ECU111in a non-energization period through linear interpolation, for example.

Here, it is assumed that the period from time t1to time t2was a non-energization period. In this case, for example, the selection unit22obtains a formula of a straight line that connects a temperature Tp1indicated by wear information having a time stamp of time t1attached thereto, and a temperature Tp2indicated by wear information having a time stamp of time t2attached thereto. Then, using the formula of the straight line, the selection unit22calculates a plurality of temperatures of the ECU111at a plurality of respective timings included in the non-energization period.

Then, on the basis of the plurality of calculated temperatures respectively corresponding to the plurality of timings included in the non-energization period, and a plurality of temperatures respectively corresponding to a plurality of timings included in an energization period, the selection unit22calculates the degree of wear of the ECU111in the predetermined period including the energization period and the non-energization period.

(a-2) Example 2

The selection unit22may calculate a degree of wear of each ECU111by using a temperature determined as a specification of the ECU111(hereinafter, also referred to as “temperature specification”). The temperature specification of each ECU111is stored in the storage unit23, for example.

Specifically, it is assumed that the temperature specification of a first ECU111is 85° C. and the actual temperature (hereinafter, also referred to as “usage temperature”) of the first ECU111in a predetermined period is 60° C. In this case, the selection unit22calculates the degree of wear of the ECU111in the predetermined period as 70.6% (=60/85).

In addition, for example, it is assumed that the temperature specification of a second ECU111is 125° C. and the usage temperature of the second ECU111in the predetermined period is 65° C. In this case, the selection unit22calculates the degree of wear of the ECU111in the predetermined period as 52.0% (=65/125).

In this calculation method, in the predetermined period, although the temperature of the second ECU111is higher than the temperature of the first ECU111, the value of the degree of wear of the second ECU111is lower than that of the degree of wear of the first ECU111.

As in “(a-1) Example 1”, in a case where the predetermined period is divided into a plurality of periods, and the selection unit22calculates a use time period of the ECU111in each divided period, the use time period in each divided period may be multiplied by a proportion of the usage temperature of the ECU111in the divided period relative to the temperature specification.

(a-3) Example 3

Here, it is assumed that the wear information is information regarding the number of times of rewriting R of a memory included in the corresponding ECU111. For example, each ECU111counts the number of times of rewriting R of the memory of the ECU111, attaches a time stamp to wear information indicating the count value, and transmits the resultant wear information together with result information and resource state information, to the management ECU101.

The life information stored in the storage unit23indicates a rewritable number of times Rmax of a memory of each of a plurality of ECUs111. For each ECU111, the selection unit22calculates the number of times of rewriting Rt in a predetermined period, on the basis of a plurality of pieces of wear information received via the communication unit21in the predetermined period from the ECU111.

For example, the selection unit22subtracts a minimum value from a maximum value of the number of times of rewriting R indicated by each of the plurality of pieces of wear information received in the predetermined period, thereby calculating an actual number of times of rewriting Rt in the predetermined period.

Then, the selection unit22calculates, as the degree of wear, the proportion of the calculated number of times of rewriting Rt relative to the rewritable number of times Rmax indicated by the life information stored in the storage unit23.

Details of Selection Process and Substitution Control

(b-1) Example 1

With reference toFIG.2again, here, it is assumed that, in the ECU group, there is an ECU111of which the degree of wear in the predetermined period is not less than a threshold Th1(hereinafter, also referred to as “high-wear-degree ECU111”). In this case, on the basis of resource state information which has been transmitted from each ECU111and which is stored in the storage unit23, the selection unit22selects one or a plurality of substitute ECUs111to be caused to perform the target process that should be performed by one or a plurality of high-wear-degree ECUs111.

More specifically, for example, as the substitute ECU111, the selection unit22selects, out of the ECU group, one or a plurality of ECUs111of which the degree of wear in the predetermined period is not greater than a threshold Th2(hereinafter, also referred to as “low-wear-degree ECU111”), and of which the use rate of resources is not greater than a threshold Th3. Then, the selection unit22outputs, to the control unit24, selection result information indicating the selected one or plurality of substitute ECUs111and the content of the target process.

Upon receiving the selection result information from the selection unit22, the control unit24transmits, on the basis of the selection result information, a processing order for causing the target process to be performed, to each substitute ECU111selected by the selection unit22. Accordingly, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to one or a plurality of ECUs111which are each a low-wear-degree ECU111and of which the use rate of resources is low.

The control unit24may further perform a control of reducing the processing load of each substitute ECU111, i.e., a control of reducing the use rate of resources such as a CPU and a memory. Accordingly, increase in the degree of wear of the substitute ECU111can be suppressed.

For example, when the target process includes a communication process to be performed with the management ECU101, the control unit24changes the communication process of the substitute ECU111such that the frequency of communication to be performed with the management ECU101is reduced. Specifically, as the control for reducing the communication frequency of the substitute ECU111with respect to the management ECU101, the control unit24performs setting such that the wear information and the result information are thinned to be transmitted, or performs setting such that the transmission cycle of the wear information and the result information is extended.

For the substitute ECU111, the control unit24may perform a control of reducing the processing load of substitute ECU111by performing setting such that the resolution of a display screen or the like is reduced.

(b-2) Example 2

It is assumed that, in the ECU group, there is no ECU111that is a low-wear-degree ECU111and of which the use rate of resources is not greater than the threshold Th3. In addition, it is assumed that none of one or a plurality of high-wear-degree ECUs111is an ECU111that performs a control related to travel of the vehicle10(hereinafter, also referred to as “travel control system ECU111”). The travel control system ECU111is the travel control device111cor the automated driving ECU111h, for example.

In this case, the selection unit22determines not to select any substitute ECU111. That is, the selection unit22determines that the target process that should be performed by one or a plurality of high-wear-degree ECUs111is not distributed to other ECUs111. Then, the selection unit22outputs, to the control unit24, selection result information indicating the determined content.

Upon receiving the selection result information from the selection unit22, the control unit24determines, in accordance with the selection result information, not to perform the substitution control for the target process.

When having determined that the target process is not distributed to other ECUs111, the selection unit22may output, to the control unit24, instruction information that instructs reduction of the processing load of each high-wear-degree ECU111.

In this case, upon receiving the instruction information from the selection unit22, the control unit24performs a control of reducing the processing load of each high-wear-degree ECU111, on the basis of the instruction information. For example, with respect to the high-wear-degree ECU111, the control unit24limits the content of the target process by making a change such that the communication frequency with the management ECU101is reduced, or by performing setting such that the resolution of a display screen or the like is reduced.

Accordingly, each high-wear-degree ECU111can suppress increase in the degree of wear by reducing the use rate of resources while performing the target process that the high-wear-degree ECU111should perform.

(b-3) Example 3

Here, it is assumed that, in the ECU group, there is no ECU111that is a low-wear-degree ECU111and of which the use rate of resources is not greater than the threshold Th3. In addition, it is assumed that at least one of one or a plurality of high-wear-degree ECUs111is the travel control system ECU111.

In this case, for example, as the substitute ECU111, the selection unit22selects, out of the ECU group, one or a plurality of ECUs111that are each an ECU111other than the travel control system ECU111and being a high-wear-degree ECU111, and of which the use rate of resources is not greater than the threshold Th3.

Then, the selection unit22outputs, to the control unit24, selection result information indicating the selected one or plurality of substitute ECUs111and the content of the target process.

Upon receiving the selection result information from the selection unit22, the control unit24transmits, on the basis of the selection result information, a processing order for causing the target process to be performed, to each substitute ECU111selected by the selection unit22.

Accordingly, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to one or a plurality of ECUs111which are each an ECU111other than the travel control system ECU111and of which the use rate of resources is low.

In addition, the control unit24may further perform a control of reducing the processing load of each substitute ECU111, as described in (b-1).

(b-4) Example 4

Here, it is assumed that, in the ECU group, there is no ECU111of which the use rate of resources is not greater than the threshold Th3, and at least one of one or a plurality of high-wear-degree ECUs111is the travel control system ECU111.

In this case, as the substitute ECU111, the selection unit22selects, out of the ECU group, an ECU111other than the travel control system ECU111, e.g., the entertainment-related device111b. Then, the selection unit22outputs, to the control unit24, selection result information indicating the selected one or plurality of substitute ECUs111and the content of the target process, and instruction information that instructs reduction of the processing load of each substitute ECU111, for example.

Upon receiving the selection result information and the instruction information from the selection unit22, the control unit24transmits, on the basis of the selection result information, a processing order for causing the target process to be performed, to each substitute ECU111selected by the selection unit22. In addition, the control unit24performs a control of reducing the processing load of each substitute ECU111, on the basis of the instruction information.

Accordingly, even in a case where there is no ECU111of which the use rate of resources is not greater than the threshold Th3, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to one or a plurality of ECUs111that would not influence traveling of the vehicle10even if the use rate of resources is reduced.

Operation Flow

Each of the devices in the on-vehicle communication system301includes a computer. An arithmetic processing unit such as a CPU in the computer reads out a program including a part or all of steps in the sequence diagram or flow chart described below from a memory (not shown), and executes the program. The programs for the plurality of devices can be installed from outside. The programs for the plurality of devices are each distributed in a state of being stored in a storage medium.

FIG.4is a flow chart showing an example of an operation flow of the on-vehicle communication system according to the first embodiment of the present disclosure.

With reference toFIG.2andFIG.4, first, each ECU111transmits, to the management ECU101, wear information, result information, and resource state information in a set transmission cycle, for example (step S11).

Next, the selection unit22in the management ECU101receives, via the communication unit21, the wear information, the result information, and the resource state information transmitted from each ECU111, and stores these pieces of information into the storage unit23. Then, for example, when a predetermined period including a plurality of the transmission cycles has elapsed, the selection unit22calculates a degree of wear of each ECU111in the predetermined period, on the basis of a plurality of pieces of the wear information stored in the storage unit23(step S12).

Next, the selection unit22in the management ECU101confirms whether or not there is a high-wear-degree ECU111in the ECU group (step S13).

When there is no high-wear-degree ECU111(“NO” in step S13), the selection unit22determines not to select any substitute ECU111(step S14). Then, until the next predetermined period has elapsed, the selection unit22repeats reception of wear information, result information, and resource state information, and storage of these pieces of information into the storage unit23. Then, when the predetermined period has elapsed, the selection unit22calculates a degree of wear of each ECU111in the predetermined period (step S12).

Meanwhile, when there is a high-wear-degree ECU111(“YES” in step S13), the selection unit22confirms, on the basis of the resource state information transmitted from each ECU111and stored in the storage unit23, whether or not, in the ECU group, there is an ECU111that is a low-wear-degree ECU111and of which the use rate of resources is not greater than the threshold Th3(step S15).

Then, when there is one or a plurality of ECUs111that are each a low-wear-degree ECU111and of which the use rate of resource is not greater than the threshold Th3(“YES” in step S15), the selection unit22selects the one or plurality of ECUs111as the substitute ECU111. Then, the selection unit22outputs, to the control unit24, selection result information indicating the selection result and the content of the target process (step S16).

Next, upon receiving the selection result information from the selection unit22, the control unit24performs, on the basis of the selection result information, a substitution control of causing each substitute ECU111selected by the selection unit22to perform the target process, and a control of reducing the processing load of each substitute ECU111, for example (step S17).

Meanwhile, when there is no ECU111that is a low-wear-degree ECU111and of which the use rate of resources is not greater than the threshold Th3(“NO” in step S15), the selection unit22confirms whether or not the high-wear-degree ECU111is the travel control system ECU111(step S18).

Then, when none of one or a plurality of high-wear-degree ECUs111is the travel control system ECU111(“NO” in step S18), the selection unit22determines not to select any substitute ECU111. Then, the selection unit22outputs, to the control unit24, selection result information indicating the determined content and instruction information that instructs reduction of the processing load of each high-wear-degree ECU111(step S19).

Next, upon receiving the selection result information and the instruction information from the selection unit22, the control unit24performs, on the basis of the selection result information and the instruction information, a control of reducing the processing load of each high-wear-degree ECU111(step S20).

Meanwhile, when at least one of one or a plurality of high-wear-degree ECUs111is the travel control system ECU111(“YES” in step S18), the selection unit22selects, as the substitute ECU111, one or a plurality of ECUs111, in the ECU group, that are each an ECU111other than the travel control system ECU111and being the high-wear-degree ECU111and of which the use rate of resources is not greater than the threshold Th3. Then, the selection unit22outputs, to the control unit24, selection result information indicating the selection result and the content of the target process (step S21).

Next, upon receiving the selection result information from the selection unit22, the control unit24performs, on the basis of the selection result information, a substitution control of causing each substitute ECU111selected by the selection unit22to perform the target process, and a control of reducing the processing load of each substitute ECU111(step S22).

In step S21, for example, when there is no ECU111of which the use rate of resources is not greater than the threshold Th3, the selection unit22may select the entertainment-related device111bor the like as the substitute ECU111. In this case, for example, the selection unit22outputs, to the control unit24, selection result information indicating the selection result and instruction information that instructs reduction of the processing load of one or a plurality of substitute ECUs111.

Then, in step S22, upon receiving the selection result information and the instruction information from the selection unit22, the control unit24performs, on the basis of the selection result information and the instruction information, a substitution control of causing each substitute ECU111selected by the selection unit22to perform the target process, and a control of reducing the processing load of each substitute ECU111.

In step S12, the selection unit22newly calculates a degree of wear of each ECU111in the next predetermined period, and when the degree of wear of an ECU111having been the high-wear-degree ECU111in the previous predetermined period has changed to be less than the threshold Th1, the selection unit22outputs, to the control unit24, end instruction information that instructs ending of the distribution of the target process that should be performed by the ECU111.

Upon receiving the end instruction information from the selection unit22, the control unit24performs, on the basis of the end instruction information, a control of causing the target process having been performed by one or a plurality of substitute ECUs111selected by the selection unit22, to be performed by one or a plurality of ECUs111that should perform the target process.

Meanwhile, in the future, the operation rate of each ECU will highly likely to be increased due to prevalence of shared cars, development of automated driving technology, and the like, and there is a demand for a technology that enables the usable time period of each ECU to be longer.

Therefore, in the management ECU101according to the first embodiment of the present disclosure, the communication unit21acquires a plurality of pieces of wear information regarding the degree of wear of each of a plurality of ECUs111mounted on the vehicle10. On the basis of each piece of the wear information acquired by the communication unit21, the selection unit22selects, from the plurality of ECUs111, one or a plurality of substitute ECUs111to be caused to perform a target process that should be performed by one or a plurality of ECUs111among the plurality of ECUs111. Then, the control unit24performs a control of causing the one or plurality of substitute ECUs111selected by the selection unit22to perform the target process.

With this configuration, for example, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to another one or plurality of ECUs111. Thus, increase in the degree of wear of each high-wear-degree ECU111can be suppressed.

Therefore, in the management ECU101according to the first embodiment of the present disclosure, the usable time period of each ECU111mounted on the vehicle10can be made longer.

In the management ECU101according to the first embodiment of the present disclosure, as the one or plurality of ECUs111to be caused to perform the target process, the selection unit22selects at least one ECU111that is different from the one or plurality of ECUs111that should perform the target process.

With this configuration, for example, the target process that should be performed by the high-wear-degree ECU111can be performed by the low-wear-degree ECU111.

The wear information acquired by the communication unit21in the management ECU101according to the first embodiment of the present disclosure includes information regarding heat of the ECU111.

With the configuration in which the substitute ECU111is selected by using the information regarding heat that could significantly influence the wear of the ECU111, the degree of wear of each ECU111can be more accurately grasped, and more appropriate selection can be performed.

The wear information acquired by the communication unit21in the management ECU101according to the first embodiment of the present disclosure includes information regarding the number of times of rewriting R of a memory included in the ECU111.

With this configuration, since the substitute ECU111is selected by using the information regarding a memory that is easily worn among electronic components of the ECU111, the degree of wear of each ECU111can be more accurately grasped, and more appropriate selection can be performed.

In the management ECU101according to the first embodiment of the present disclosure, the control unit24further performs a control of reducing the processing load of the one or plurality of substitute ECUs111selected by the selection unit22.

With this configuration, for example, the processing load of each substitute ECU111can be reduced. Thus, increase in the degree of wear of the substitute ECU111to which the target process is distributed can be suppressed.

In the management ECU101according to the first embodiment of the present disclosure, the control unit24changes the communication frequency of the substitute ECU111, as the control of reducing the processing load.

With this configuration, for example, by setting the communication frequency of the substitute ECU111so as to be reduced, it is possible to reduce the processing load of the substitute ECU111.

In the management ECU101according to the first embodiment of the present disclosure, when no substitute ECU111is selected by the selection unit22, the control unit24performs a control of reducing the processing load of the high-wear-degree ECU111that performs the target process.

With this configuration, even when there is no appropriate ECU111to which the target process is distributed, increase in the degree of wear of the high-wear-degree ECU111that performs the target process can be suppressed.

In the management ECU101according to the first embodiment of the present disclosure, the degree of wear is a proportion of an actual use time period in a predetermined period relative to a usable time period of the ECU111, or a proportion of an actual number of times of rewriting in a predetermined period relative to a rewritable number of times of a memory included by the ECU111. The wear information is information regarding history of the temperature of the ECU111, or information regarding the rewritable number of times of the memory. The temperature is a temperature influenced by both of the ambient temperature of the ECU111and generated heat of the ECU111. The generated heat of the ECU111includes heat generated due to operation of various resources in the ECU111, heat generated due to turning on/off of a power supply of the ECU111, and heat generated due to occurrence of a ripple current.

With this configuration, since the substitute ECU111is selected by using information regarding heat that could significantly influence wear of the ECU111or regarding a memory that is easily worn among electronic components of the ECU111, the degree of wear of each ECU111can be more accurately grasped, and a more appropriate substitute ECU111can be selected.

In a control method to be performed in the management ECU101according to the first embodiment of the present disclosure, first, the communication unit21acquires wear information regarding the degree of wear of each of a plurality of ECUs111mounted on the vehicle10. Next, on the basis of each piece of the wear information acquired by the communication unit21, the selection unit22selects, from an ECU group composed of a plurality of ECUs111, one or a plurality of substitute ECUs111to be caused to perform a target process that should be performed by at least one ECU111in the ECU group. Then, the control unit24performs a substitution control of causing the one or plurality of substitute ECUs111selected by the selection unit22, to perform the target process.

With this method, for example, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to another one or plurality of ECUs111. Thus, increase in the degree of wear of each high-wear-degree ECU111can be suppressed.

Therefore, in the control method performed in the management ECU101according to the first embodiment of the present disclosure, the usable time period of each ECU111mounted on the vehicle10can be made longer.

Next, another embodiment of the present disclosure is described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference signs, and descriptions thereof are not repeated.

Second Embodiment

In the first embodiment described above, the management ECU101mounted on the vehicle10calculates the degree of wear of each ECU111, and performs the selection process of the substitute ECU111on the basis of the calculated degree of wear of each ECU111. In contrast to this, in the second embodiment, a management server (management device)121estimates the degree of wear of each ECU111mounted on a vehicle11, and the management ECU101in the vehicle11performs a selection process of the substitute ECU111on the basis of an estimation result by the management server121. Except for the contents described below, the configuration is the same as that of the on-vehicle communication system301according to the first embodiment.

Configuration and Basic Operation

FIG.5shows a configuration of a control system according to the second embodiment of the present disclosure.

With reference toFIG.5, a control system302includes one or a plurality of the vehicles11, the management server121, a dealer-side server131, and a wireless base station device161. InFIG.5, two vehicles11are shown as an example.

The vehicle11according to the second embodiment includes the management ECU101and a plurality of ECUs111, as in the vehicle10shown inFIG.1. As shown inFIG.2, the management ECU101includes the communication unit21, the selection unit22, the storage unit23, and the control unit24.

The selection unit22transmits, to the management server121, a plurality of pieces of wear information respectively received from the plurality of ECUs111, via the communication unit21, the extra-vehicular communication device111ashown inFIG.1, and the wireless base station device161.

The dealer-side server131holds failure information regarding failures of a plurality of ECUs111. The failure information indicates, for example, a correspondence relationship between the type of the ECU111, the date of manufacture of the ECU111, the use period of the ECU111, and the number of ECUs111that have failed among a plurality of ECUs111manufactured on the date of manufacture.

The dealer-side server131periodically or non-periodically updates the failure information, for example, and transmits the updated failure information to the management server121via the wireless base station device161.

On the basis of the plurality of pieces of the wear information received via the wireless base station device161from each vehicle11, and the failure information received via the wireless base station device161from the dealer-side server131, the management server121estimates a degree of wear of each of the plurality of ECUs111in each vehicle11.

Specifically, the wear information from the vehicle11indicates the type, the date of manufacture, etc., of each ECU111, for example. With reference the type and date of manufacture of each of the plurality of ECUs111respectively indicated by the plurality of pieces of the wear information received from the vehicle11, and the above-described correspondence relationship indicated by the failure information, the management server121estimates, as the usable time period, a time period until the probability of occurrence of a failure becomes not less than a predetermined value.

The management server121calculates a use time period of each ECU111on the basis of the corresponding wear information, and calculates, for each ECU111, a proportion of the use time period relative to the estimated usable time period, thereby estimating a degree of wear of each ECU111.

Then, the management server121transmits estimation information indicating the estimated degree of wear of each ECU111, and the type, date of manufacture, etc., of each ECU111, to the one or a plurality of the vehicles11and the dealer-side server131via the wireless base station device161.

The selection unit22in the vehicle11receives the estimation information transmitted from the management server121, via the wireless base station device161, the extra-vehicular communication device111a, and the communication unit21. Then, on the basis of the received estimation information, the selection unit22selects, from the ECU group in the vehicle11, one or a plurality of substitute ECUs111to be caused to perform a target process.

More specifically, on the basis of the received estimation information, the selection unit22calculates a degree of wear of each ECU111in the vehicle11. For example, for each ECU111, the selection unit22assigns weights to the degree of wear calculated by using the method described in (a-1) or the method described in (a-2) and to the degree of wear indicated by the received estimation information, and performs addition thereof. Accordingly, the selection unit22calculates a degree of wear of each ECU111reflecting the content of the estimation information.

Then, on the basis of the calculated degree of wear of each ECU111, and the corresponding resource state information stored in the storage unit23, the selection unit22performs a selection process of the substitute ECU111.

The selection unit22may not necessarily perform the calculation of the degree of wear of each ECU111. In this case, for example, the selection unit22determines the magnitude of the degree of wear of each ECU111by using the estimation information received from the management server121, and performs a selection process of the substitute ECU111.

The dealer-side server131receives, via the wireless base station device161, the estimation information transmitted from the management server121, and on the basis of the received estimation information, determines whether the degree of wear of each ECU111estimated by the management server121is valid.

For example, on the basis of the failure information held by the dealer-side server131, and the type, date of manufacture, etc., of each ECU111indicated by the estimation information received from the management server121, the dealer-side server131specifies one or a plurality of ECUs111that are highly likely to fail. In addition, the dealer-side server131confirms the corresponding degree of wear indicated by the estimation information, thereby determining whether the degree of wear of each ECU111estimated by the management server121is valid.

Then, for example, the dealer-side server131transmits, to the management server121via the wireless base station device161, determination result information indicating a validity determination result.

When the vehicle11has broken down, the dealer-side server131can use the estimation information and the validity determination result received from the management server121, in estimation of the cause of the breakdown of the vehicle11.

Operation Flow

FIG.6is a sequence diagram showing an example of an operation flow of the control system according to the second embodiment of the present disclosure.

With reference toFIG.5andFIG.6, first, the management ECU101in the vehicle11periodically or non-periodically transmits wear information of each ECU111to the management server121via the extra-vehicular communication device111aand the wireless base station device161(step S31).

Next, for example, every time the dealer-side server131updates failure information held therein, the dealer-side server131transmits the updated failure information to the management server121via the wireless base station device161(step S32).

Next, on the basis of the plurality of pieces of the wear information received from the vehicle11and the failure information received from the dealer-side server131, the management server121estimates a degree of wear of each ECU111in the vehicle11(step S33).

Next, the management server121transmits estimation information indicating the estimated degree of wear of each ECU111to the vehicle11and the dealer-side server131via the wireless base station device161(step S34).

Next, on the basis of the estimation information received from the management server121, the dealer-side server131determines whether the degree of wear of each ECU111estimated by the management server121is valid (step S35). Then, the dealer-side server131transmits determination result information indicating the determination result, to the management server121via the wireless base station device161(step S36).

Meanwhile, on the basis of the estimation information received from the management server121, the selection unit22in the vehicle11calculates a degree of wear of each ECU111in the vehicle11(step S37) as in step S12shown inFIG.4, and then performs operations similar to the operations shown inFIG.4.

The other configurations and operations are the same as those of the on-vehicle communication system301according to the first embodiment of the present disclosure, and thus detailed descriptions thereof are not repeated.

As described above, in the control system302according to the second embodiment of the present disclosure, with respect to a plurality of vehicles11, the management server121: acquires a plurality of pieces of wear information regarding the degree of wear of each of a plurality of ECUs111mounted on each vehicle11; on the basis of the acquired each piece of the wear information, estimates a degree of wear of one or a plurality of ECUs111in the vehicle11on which a management ECU101is mounted; and transmits estimation information indicating an estimation result, to the management ECU101. Then, the management ECU101: receives the estimation information transmitted from the management server121; on the basis of the received estimation information, selects, from the plurality of ECUs111in the vehicle11on which the management ECU101is mounted, one or a plurality of substitute ECUs111to be caused to perform a target process that should be performed by one or a plurality of ECUs111among the plurality of ECUs111; and performs a substitution control of causing the selected one or plurality of substitute ECUs111to perform the target process.

With this configuration, for example, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to another one or plurality of substitute ECUs111. Thus, increase in the degree of wear of each high-wear-degree ECU111can be suppressed.

With the configuration in which the management server121estimates a degree of wear of each ECU111, for example, a more accurate degree of wear can be calculated in the vehicle11by using both of the degree of wear estimated by the management server121and the degree of wear calculated in the vehicle11.

Therefore, in the control system302according to the second embodiment of the present disclosure, the usable time period of each ECU111mounted on the vehicle11can be made longer.

In the control system302according to the second embodiment of the present disclosure, the dealer-side server131holds failure information regarding failures of a plurality of ECUs111. The dealer-side server131transmits the failure information to the management server121. The management server121estimates a degree of wear of one or a plurality of ECUs111on the basis of the acquired each piece of the wear information and the failure information received from the dealer-side server131.

With the configuration in which the management server121estimates a degree of wear of each ECU111on the basis of the wear information and the failure information, a more accurate degree of wear can be calculated.

In a control method to be performed in the control system302according to the second embodiment of the present disclosure, first, with respect to a plurality of vehicles11, the management server121acquires a plurality of pieces of wear information regarding the degree of wear of each of a plurality of ECUs111mounted on each vehicle11. Next, on the basis of the acquired each piece of the wear information, the management server121estimates a degree of wear of one or a plurality of ECUs111in the vehicle11on which a management ECU101is mounted, and transmits estimation information indicating an estimation result, to the management ECU101. Next, the management ECU101: receives the estimation information transmitted from the management server121; and on the basis of the received estimation information, selects, from the plurality of ECUs111in the vehicle11on which the management ECU101is mounted, one or a plurality of substitute ECUs111to be caused to perform a target process that should be performed by one or a plurality of ECUs111among the plurality of ECUs111. Then, the management ECU101performs a substitution control of causing the selected one or plurality of substitute ECUs111to perform the target process.

With this method, for example, the target process that should be performed by one or a plurality of high-wear-degree ECUs111can be distributed to another one or plurality of substitute ECUs111. Thus, increase in the degree of wear of each high-wear-degree ECU111can be suppressed.

With the method in which the management server121estimates a degree of wear of each ECU111, for example, a more accurate degree of wear can be calculated in the vehicle11by using both of the degree of wear estimated by the management server121and the degree of wear calculated in the vehicle11.

Therefore, in the control method performed in the control system302according to the second embodiment of the present disclosure, the usable time period of each ECU111mounted on the vehicle11can be made longer.

The features of the on-vehicle communication system301according to the first embodiment of the present disclosure and the features of the control system302of the second embodiment can also be combined as appropriate.

The disclosed embodiments are merely illustrative in all aspects and should not be recognized as being restrictive. The scope of the present disclosure is defined by the scope of the claims rather than by the description above, and is intended to include meaning equivalent to the scope of the claims and all modifications within the scope.

REFERENCE SIGNS LIST

10,11vehicle21communication unit (acquisition unit)22selection unit23storage unit24control unit101management ECU (on-vehicle control device)111ECU (function unit)111aextra-vehicular communication device111bentertainment-related device111ctravel control device111dcamera111eobject detection sensor111ftemperature sensor111gbattery state monitoring sensor111hautomated driving ECU121management server (management device)131dealer-side server161wireless base station device301on-vehicle communication system302control system