Life prediction device and life prediction method

Abstract

A life prediction device (100) includes an operation history accumulation unit (102) that accumulates the operation history of parts constituting a vehicle; a life prediction unit (103) that calculates the cumulative pressure and pressure increase rate on the parts based on the operation history, and predicts the remaining driving distance until the parts' lifespan is exhausted based on the cumulative pressure and pressure increase rate; a usage domain frequency calculation unit (104) that calculates the usage domain frequency of the internal combustion engine installed in the vehicle based on the engine speed and load; a usage domain frequency storage unit (105) that stores the usage domain frequency; and a deviation calculation unit (106) that calculates the deviation between the latest value of the usage domain frequency and the previous value of the usage domain frequency. When the deviation is above a threshold, the life prediction unit (103) calculates the increase rate only based on the operation history accumulated after the latest value is calculated, thus solving the technical problem.

Description

Technical Field

[0001] This disclosure relates to a life prediction device and method for predicting the lifespan of components constituting a vehicle. Background Technology

[0002] The parts that make up a vehicle will gradually age as they are used and eventually reach the end of their lifespan. Therefore, in order to perform appropriate maintenance (e.g., parts replacement) before the parts reach the end of their lifespan, it is desirable to predict the lifespan of the parts.

[0003] Therefore, in the past, the operational history of parts was accumulated, and the lifespan of parts was predicted based on the operational history (for example, see Patent Documents 1 and 2).

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2012-233336

[0007] Patent Document 2: Japanese Patent Application Publication No. 2020-042705

[0008] Content of the invention

[0009] The technical problem that the invention aims to solve

[0010] However, when lifespan is predicted based on operational history, for example, if the vehicle is resold and the user or route of the vehicle is changed, i.e. if the vehicle's usage conditions change, the rate at which parts age can sometimes vary significantly before and after the change in vehicle usage conditions.

[0011] Therefore, it is difficult to predict the lifespan accurately because there is a risk of large errors if the lifespan is predicted without taking into account changes in vehicle usage.

[0012] In view of the above, the purpose of this disclosure is to provide a life prediction device and life prediction method that can make more accurate predictions than in the past when predicting life based on operational history.

[0013] Technical means for solving technical problems

[0014] A lifespan prediction device is provided, comprising: an operation history accumulation unit that accumulates operation history of parts constituting a vehicle; a lifespan prediction unit that calculates cumulative pressure and pressure increase rate on the parts based on the operation history accumulated in the operation history accumulation unit, and predicts the remaining driving distance until the parts reach the end of their lifespan based on the cumulative pressure and the pressure increase rate; a usage domain frequency calculation unit that calculates the usage domain frequency of an internal combustion engine installed in the vehicle based on the rotational speed and load of the internal combustion engine; a usage domain frequency storage unit that stores the usage domain frequency calculated in the usage domain frequency calculation unit; and a deviation calculation unit that calculates the deviation between the latest value of the usage domain frequency stored in the usage domain frequency storage unit and the previous value of the usage domain frequency, wherein if the deviation between the latest value of the usage domain frequency calculated by the deviation calculation unit and the previous value of the usage domain frequency is above a threshold, the lifespan prediction unit calculates the pressure increase rate only based on the operation history accumulated after the latest value of the usage domain frequency is calculated.

[0015] Preferably, the system further includes: a location determination unit that determines the location of the vehicle; a location storage unit that stores the location determined by the location determination unit; a usage environment determination unit that determines the usage environment of the vehicle based on the location stored in the location storage unit; and a usage environment storage unit that stores the usage environment determined by the usage environment determination unit. The deviation calculation unit calculates the deviation between the latest value of the usage environment stored in the usage environment storage unit and the previous value of the usage environment. If the deviation between the latest value of the usage environment calculated by the deviation calculation unit and the previous value of the usage environment is above a threshold, the life prediction unit calculates the pressure increase rate based solely on the operating history accumulated after the latest value of the usage environment was calculated.

[0016] Preferably, the usage environment determination unit determines the vehicle's operating route based on the location stored in the location storage unit, and sets the operating route as the usage environment if the operating route is consistent multiple times.

[0017] Preferably, the position determination unit determines the position of the internal combustion engine installed in the vehicle when it is cold-started. If the position stored in the position storage unit is consistent multiple times, the usage environment determination unit sets that position as the usage environment.

[0018] Preferably, it further includes: a change detection unit that detects changes to the vehicle registration plate installed on the vehicle; if the change detection unit detects a change to the vehicle registration plate, the life prediction unit calculates the pressure increase rate based solely on the accumulated operating history after the change to the vehicle registration plate is detected.

[0019] Additionally, a lifespan prediction method is provided, comprising: an operation history accumulation step, which accumulates the operation history of components constituting a vehicle; a lifespan prediction step, which calculates the cumulative pressure and pressure increase rate on the components based on the operation history accumulated in the operation history accumulation step, and predicts the remaining driving distance until the components reach the end of their lifespan based on the cumulative pressure and the pressure increase rate; a usage domain frequency calculation step, which calculates the usage domain frequency of the internal combustion engine installed in the vehicle based on the rotational speed and load; a usage domain frequency storage step, which stores the usage domain frequency calculated in the usage domain frequency calculation step; and a deviation calculation step, which calculates the deviation between the latest value of the usage domain frequency stored in the usage domain frequency storage step and the previous value of the usage domain frequency; in the lifespan prediction step, if the deviation between the latest value of the usage domain frequency calculated in the deviation calculation step and the previous value of the usage domain frequency is above a threshold, the pressure increase rate is calculated only based on the operation history accumulated after the latest value of the usage domain frequency is calculated.

[0020] Invention Effects

[0021] This invention provides a life prediction device and method that can make more accurate predictions than before when predicting life based on operational history. Attached Figure Description

[0022] Figure 1 This is a diagram illustrating the life prediction device according to the first embodiment.

[0023] Figure 2 It is an explanation of being Figure 1 A diagram illustrating the life prediction method implemented by the life prediction device.

[0024] Figure 3 This is a diagram illustrating the lifespan prediction device according to the second embodiment.

[0025] Figure 4 It is an explanation of being Figure 3 A diagram illustrating the life prediction method implemented by the life prediction device.

[0026] Figure 5 This is a diagram illustrating the lifespan prediction device according to the third embodiment.

[0027] Figure 6 It is an explanation of being Figure 5 A diagram illustrating the life prediction method implemented by the life prediction device.

[0028] Figure 7 This is a diagram illustrating the lifespan prediction device according to the fourth embodiment.

[0029] Figure 8 It is an explanation of being Figure 7 A diagram illustrating the life prediction method implemented by the life prediction device. Detailed Implementation

[0030] [First Implementation]

[0031] like Figure 1 As shown, the lifespan prediction device 100 according to the first embodiment is composed of a portion of the functions of the control device 101, including an operation history accumulation unit 102, a lifespan prediction unit 103, a usage domain frequency calculation unit 104, a usage domain frequency storage unit 105, and a deviation calculation unit 106. The control device 101 is, for example, an engine control unit having a central computing processing unit and a storage area.

[0032] The operating history accumulation unit 102 accumulates the operating history of the parts that make up the vehicle (e.g., the parts that make up the internal combustion engine mounted on the vehicle). The operating history is the time-dependent change of the measured values ​​of various factors that cause the parts to age (e.g., outdoor temperature, vehicle travel distance, vehicle position, internal combustion engine coolant temperature, internal combustion engine speed, and / or internal combustion engine load).

[0033] The life prediction unit 103 calculates the cumulative pressure and pressure increase rate on the component based on the operating history accumulated in the operating history accumulation unit 102, and predicts the remaining driving distance of the component until its lifespan is exhausted based on the cumulative pressure and pressure increase rate. The cumulative pressure is the sum of the loads applied to the component from the time it was assembled on the vehicle (from a new state) until the present. The pressure increase rate (the change in cumulative pressure per unit driving distance) is the rate at which the component ages. The life prediction unit 103 preferably informs the vehicle user or manager of the remaining driving distance. It may also warn the user or manager to perform maintenance as soon as possible if the remaining driving distance is determined to be low or zero (i.e., the component's lifespan is completely exhausted). Furthermore, the remaining driving distance can also be referred to as the remaining operating time. When the remaining driving distance is referred to as the remaining operating time, the change in cumulative pressure per unit operating time is set as the pressure increase rate. When predicting remaining driving distance based on accumulated pressure and the rate of pressure increase, a pre-determined accumulated pressure (lifespan threshold) is experimentally determined, assuming the component's lifespan will be exhausted. The component's aging degree is calculated based on the ratio of the current accumulated pressure to the lifespan threshold (current accumulated pressure / lifespan threshold × 100). The rate of aging (the change in aging degree per unit driving distance) is calculated based on the rate of pressure increase. Only the remaining driving distance before the aging degree reaches 100 needs to be calculated. Specifically, assuming the current accumulated pressure is 300, the lifespan threshold is 1000, and the pressure increase rate is 100 per 100,000 km, and the current aging degree is 30, with a rate of aging of 10 per 100,000 km, if the rate of pressure increase remains constant, the remaining driving distance before the aging degree reaches 100 is 700,000 km.

[0034] The usage frequency calculation unit 104 calculates the usage frequency of the internal combustion engine based on its speed and load. Usage frequency refers to the frequency of use in each speed range and load range, for example, where the engine is used extensively in low-speed, low-load areas and generally used from low-load to high-load areas in high-speed areas. If the vehicle's usage conditions change, the usage frequency will naturally change as well. That is, a significant change in usage frequency indicates a change in the vehicle's usage conditions. Furthermore, the usage frequency is calculated within a predetermined period, which is, for example, one cycle from when the internal combustion engine is started until it is stopped. The usage frequency storage unit 105 stores the usage frequency calculated by the usage frequency calculation unit 104.

[0035] The divergence calculation unit 106 calculates the divergence between the latest value of the usage domain frequency stored in the usage domain frequency storage unit 105 and the previous value of the usage domain frequency. The usage domain frequency calculated in the current period is the latest value, and the usage domain frequency calculated in the previous period is the previous value. Furthermore, the divergence can be any indicator that can evaluate the correlation between the latest value and the previous value, and the magnitude of the divergence can be determined based on the difference between the latest value and the previous value or the consistency rate between the latest value and the previous value.

[0036] Previously, predicting lifespan without considering changes in vehicle usage conditions was difficult due to the risk of increased error.

[0037] In the life prediction device 100, when the deviation between the latest value of the usage domain frequency calculated by the deviation calculation unit 106 and the previous value of the usage domain frequency exceeds a threshold, the life prediction unit 103 calculates the pressure increase rate based solely on the operating history accumulated since the latest value of the usage domain frequency was calculated. That is, before and after a change in vehicle usage conditions, the rate of component aging sometimes changes significantly. If the remaining driving distance is predicted without considering the changes in the rate of component aging, it is difficult to accurately predict the remaining driving distance. Therefore, in the life prediction device 100, the operating history accumulated before the change in vehicle usage conditions and the operating history accumulated after the change in vehicle usage conditions are separated, and the pressure increase rate is calculated solely based on the operating history accumulated after the change in vehicle usage conditions. To accurately correlate changes in vehicle usage conditions with changes in usage domain frequency, a threshold is experimentally determined in advance. Furthermore, since the accumulated pressure is the sum of the loads applied to the parts from the time the parts were assembled on the vehicle (from the time they were new) until the present, regardless of changes in the vehicle's usage conditions, it is necessary to calculate it based on the entire operating history.

[0038] Therefore, in the life prediction device 100, when the deviation between the latest value of the usage domain frequency and the previous value of the usage domain frequency exceeds a threshold, the pressure increase rate is calculated only based on the accumulated operating history after the latest value of the usage domain frequency is calculated. Furthermore, the accumulated pressure is calculated based on the operating history before and after the latest value of the usage domain frequency is calculated. For example, in the aforementioned example, when the aging degree is 30, the vehicle's usage condition changes, and the rate of component aging, i.e., the pressure increase rate, becomes 200 per 100,000 km, after 100,000 km have been driven. The current accumulated pressure is calculated based on the operating history before and after the change in vehicle usage condition as: 300 before the change in vehicle usage condition + 200 after the change in vehicle usage condition = 500. The pressure increase rate is calculated only based on the operating history after the change in vehicle usage condition as 200 per 100,000 km. Furthermore, the rate of aging is calculated as 20 per 100,000 km, and the current aging level is calculated as the aging level before the change in vehicle usage (30) + the aging level after the change in vehicle usage (20) = 50. Finally, the remaining driving distance is calculated as the aging level of the part until the end of its lifespan (50) / the rate of aging (20) per 100,000 km = 250,000 km.

[0039] Furthermore, conventional methods do not consider changes in vehicle usage conditions when predicting lifespan. For example, in the aforementioned case, the current accumulated pressure is 500. Since the distance traveled until the accumulated pressure is reached is 300,000 km before the change in vehicle usage conditions + 100,000 km after the change in vehicle usage conditions = 400,000 km, the pressure increase rate is calculated as 125 per 100,000 km, and the aging rate is calculated as 12.5 per 100,000 km. Therefore, the remaining driving distance is calculated as aging degree 50 until the component's lifespan is exhausted / aging rate 12.5 per 100,000 km = 400,000 km, a value far removed from the accurate remaining driving distance of 250,000 km calculated by the lifespan prediction device 100.

[0040] like Figure 2 As shown, the life prediction method M100 implemented by the life prediction device 100 includes an operation history accumulation step S101, a usage domain frequency calculation step S102, a usage domain frequency storage step S103, a deviation calculation step S104, and a life prediction step S105. The main difference compared to previous methods is the inclusion of a usage domain frequency storage step S103 and a deviation calculation step S104 between the operation history accumulation step S101 and the life prediction step S105.

[0041] In the operation history accumulation process S101, the operation history accumulation unit 102 accumulates the operation history of the parts constituting the vehicle. In the usage domain frequency calculation process S102, the usage domain frequency calculation unit 104 calculates the usage domain frequency of the internal combustion engine based on the speed and load of the internal combustion engine installed in the vehicle.

[0042] In the usage domain frequency storage step S103, the usage domain frequency storage unit 105 stores the usage domain frequency calculated in the usage domain frequency calculation step S102. In the deviation calculation step S104, the deviation calculation unit 106 calculates the deviation between the latest value of the usage domain frequency stored in the usage domain frequency storage step S103 and the previous value of the usage domain frequency. Furthermore, if the usage domain frequency is calculated for the first time and there is no previous value, it is determined in the deviation calculation step S104 that there is no deviation.

[0043] In the life prediction process S105, the life prediction unit 103 calculates the cumulative pressure and pressure increase rate of the component based on the operating history accumulated in the operating history accumulation process S101, and predicts the remaining travel distance of the component until its life is exhausted based on the cumulative pressure and pressure increase rate. However, if the deviation between the latest value of the usage domain frequency calculated in the deviation calculation process S104 and the previous value of the usage domain frequency is above a threshold, the pressure increase rate is calculated only based on the operating history accumulated after the latest value of the usage domain frequency is calculated. Furthermore, if the deviation between the latest value of the usage domain frequency calculated by the deviation calculation process S104 and the previous value of the usage domain frequency is below a threshold, not only the operating history accumulated after the latest value of the usage domain frequency is calculated, but also the operating history accumulated before the latest value of the usage domain frequency is calculated is used in the calculation of the pressure increase rate.

[0044] Therefore, according to the life prediction device 100 and the life prediction method M100 implemented by the life prediction device 100, since the operation history accumulated before the change of vehicle usage conditions is not used in the calculation of the pressure increase rate, but only the operation history accumulated after the change of vehicle usage conditions is calculated, the remaining driving distance until the end of the component life can be predicted more accurately than before when the accumulated pressure and the pressure increase rate are used to predict.

[0045] [Second Implementation]

[0046] like Figure 3As shown, the lifespan prediction device 200 according to the second embodiment is composed of a portion of the functions of the control device 201, including an operation history accumulation unit 202, a lifespan prediction unit 203, a position determination unit 204, a position storage unit 205, a basic operating route determination unit 206 (as a type of operating environment determination unit), a basic operating route storage unit 207 (as a type of operating environment storage unit), and a deviation calculation unit 208. The control device 201 is, for example, an engine control unit having a central computing processing unit and a storage area.

[0047] The operation history accumulation unit 202 accumulates the operation history of the parts that make up the vehicle. The operation history is the time-dependent change of various detection values ​​(e.g., outdoor temperature, vehicle travel distance, vehicle position, coolant temperature of the internal combustion engine installed in the vehicle, engine speed, and / or engine load) that are factors that cause the parts to age.

[0048] The life prediction unit 203 calculates the cumulative pressure and pressure increase rate on the component based on the operating history accumulated in the operating history accumulation unit 202, and predicts the remaining driving distance of the component until its lifespan is exhausted based on the cumulative pressure and pressure increase rate. The cumulative pressure is the sum of the loads applied to the component from the time it was assembled on the vehicle (from a new state) until the present. The pressure increase rate (the change in cumulative pressure per unit driving distance) is the rate at which the component ages. The life prediction unit 203 preferably informs the vehicle user or manager of the remaining driving distance. It may also warn the user or manager to perform maintenance as soon as possible if the remaining driving distance is determined to be low or zero (i.e., the component's lifespan is completely exhausted). Furthermore, the remaining driving distance can also be referred to as the remaining operating time. When the remaining driving distance is referred to as the remaining operating time, the change in cumulative pressure per unit operating time is set as the pressure increase rate. When predicting the remaining driving distance based on accumulated pressure and the rate of pressure increase, the accumulated pressure (lifespan threshold) at which the component's lifespan is assumed to be exhausted is determined experimentally in advance. The aging degree of the component is calculated based on the ratio of the current accumulated pressure to the lifespan threshold (current accumulated pressure / lifespan threshold × 100). The rate of aging (the change in aging degree per unit driving distance) is calculated based on the rate of pressure increase. The remaining driving distance until the aging degree reaches 100 is calculated.

[0049] The location determination unit 204 determines the vehicle's location at predetermined intervals (e.g., every few seconds) by utilizing location information from a global positioning system, for example. The location storage unit 205 stores the locations determined by the location determination unit 204.

[0050] The basic operating route determination unit 206 determines a basic operating route for the vehicle, which is a form of the vehicle's operating environment, based on the positions stored in the position storage unit 205. Specifically, the operating route determined based on the positions stored in the position storage unit 205 (for example, a route formed by connecting multiple positions stored from the start to the stop of the internal combustion engine in chronological order) is set as the basic operating route if the operating route is consistent multiple times (i.e., assuming the vehicle travels on the same operating route multiple times). The basic operating route storage unit 207 stores the basic operating route determined by the basic operating route determination unit 206.

[0051] The deviation calculation unit 208 calculates the deviation between the latest value and the previous value of the basic operating route stored in the basic operating route storage unit 207. The most recently determined basic operating route is the latest value, and the basic operating route determined before the latest value is the previous value. Furthermore, the deviation can be any indicator that can evaluate the correlation between the latest and previous values, and the magnitude of the deviation is determined based on the difference between the latest and previous values ​​or the consistency rate between the latest and previous values. If the vehicle's usage conditions change, the basic operating route will naturally change as well. That is, a significant change in the basic operating route indicates a change in the vehicle's usage conditions.

[0052] In the life prediction device 200, when the deviation between the latest value of the basic operating route calculated by the deviation calculation unit 208 and the previous value of the basic operating route exceeds a threshold, the life prediction unit 203 calculates the pressure increase rate based solely on the operating history accumulated since the latest value of the basic operating route was determined. That is, before and after a change in vehicle usage conditions, the rate of component aging can sometimes change significantly. If the remaining driving distance is predicted without considering the changed rate of component aging, it is difficult to accurately predict the remaining driving distance. Therefore, in the life prediction device 200, the operating history accumulated before and after the change in vehicle usage conditions is separated, and the pressure increase rate is calculated solely based on the operating history accumulated after the change in vehicle usage conditions. To accurately correlate changes in vehicle usage conditions with changes in the basic operating route, a threshold is experimentally determined in advance. Furthermore, regardless of changes in vehicle usage, the cumulative pressure is the sum of the loads applied to the parts from the time they were assembled on the vehicle (from their new condition) until the present. It will not decrease or disappear due to changes in vehicle usage. Therefore, it is necessary to calculate it based on the entire operating history.

[0053] Therefore, in the life prediction device 200, when the deviation between the latest value of the basic operating route and the previous value of the basic operating route exceeds a threshold, the pressure increase rate is calculated only based on the accumulated operating history since the latest value of the basic operating route was determined. Furthermore, the accumulated pressure is calculated based on the operating history before the latest value of the basic operating route was determined and the operating history after the latest value of the basic operating route was determined.

[0054] like Figure 4 As shown, the life prediction method M200 implemented by the life prediction device 200 includes: an operation history accumulation process S201, a position determination process S202, a position storage process S203, a basic operating route determination process S204, a basic operating route storage process S205, a deviation calculation process S206, and a life prediction process S207. Between the operation history accumulation process S201 and the life prediction process S207, there is also a position determination process S202, a position storage process S203, a basic operating route determination process S204, a basic operating route storage process S205, and a deviation calculation process S206, which is the main difference compared to previous methods.

[0055] In the operation history accumulation process S201, the operation history accumulation unit 202 accumulates the operation history of the parts constituting the vehicle. In the position determination process S202, the position determination unit 204 determines the position of the vehicle. In the position storage process S203, the position storage unit 205 stores the position determined in the position determination process S202.

[0056] In the basic route determination procedure S204, the basic route determination unit 206 determines the basic route of the vehicle based on the position stored in the position storage program S203. In the basic route storage program S205, the basic route storage unit 207 stores the basic route determined in the basic route determination procedure S204. Furthermore, in the basic route determination procedure S204, the vehicle's route is determined based on the position stored in the position storage program S203. If the route is consistent multiple times, that route is set as the basic route.

[0057] In the deviation calculation step S206, the deviation calculation unit 208 calculates the deviation between the latest value of the basic operating route stored in the basic operating route storage program S205 and the previous value of the basic operating route. Furthermore, if there is no previous value when the basic operating route is initially determined, it is determined that there is no deviation in the deviation calculation step S206.

[0058] In the life prediction process S207, the life prediction unit 203 calculates the cumulative pressure and pressure increase rate of the part based on the operating history accumulated in the operating history accumulation process S201, and predicts the remaining travel distance of the part until its life is exhausted based on the cumulative pressure and pressure increase rate. However, if the deviation between the latest value of the basic operating route calculated by the deviation calculation process S206 and the previous value of the basic operating route is above a threshold, the pressure increase rate is calculated only based on the operating history accumulated after the latest value of the basic operating route was determined. On the other hand, if the deviation between the latest value of the basic operating route calculated by the deviation calculation process S206 and the previous value of the basic operating route is below a threshold, not only the operating history accumulated after the latest value of the basic operating route was determined is used, but also the operating history accumulated before the latest value of the basic operating route was determined is used in the calculation of the pressure increase rate.

[0059] Therefore, according to the life prediction device 200 and the life prediction method M200 implemented by the life prediction device 200, since the operation history accumulated before the change of vehicle usage conditions is not used in the calculation of the pressure increase rate, but only the operation history accumulated after the change of vehicle usage conditions is used to calculate the pressure increase rate, the remaining driving distance until the end of the component life can be predicted more accurately than before.

[0060] [Third Implementation]

[0061] like Figure 5 As shown, the lifespan prediction device 300 according to the third embodiment is composed of a portion of the functions of the control device 301, including an operation history accumulation unit 302, a lifespan prediction unit 303, a position determination unit 304, a position storage unit 305, a storage location determination unit 306 (as a type of usage environment determination unit), a storage location storage unit 307 (as a type of usage environment storage unit), and a deviation calculation unit 308. The control device 301 is, for example, an engine control unit having a central computing processing unit and a storage area.

[0062] The operation history accumulation unit 302 accumulates the operation history of the parts that make up the vehicle. The operation history is the time-dependent change of various detection values ​​(e.g., outdoor temperature, vehicle travel distance, vehicle position, coolant temperature of the internal combustion engine installed in the vehicle, engine speed, and / or engine load) that are factors that cause the parts to age.

[0063] The life prediction unit 303 calculates the cumulative pressure and pressure increase rate on the component based on the operating history accumulated in the operating history accumulation unit 302, and predicts the remaining driving distance of the component until its lifespan is exhausted based on the cumulative pressure and pressure increase rate. The cumulative pressure is the sum of the loads applied to the component from the time it was assembled on the vehicle (from a new state) until the present. The pressure increase rate (the change in cumulative pressure per unit driving distance) is the rate at which the component ages. The life prediction unit 303 preferably informs the vehicle user or manager of the remaining driving distance. It may also warn the user or manager to perform maintenance as soon as possible if the remaining driving distance is determined to be low or zero (i.e., the component's lifespan is completely exhausted). Furthermore, the remaining driving distance can also be referred to as the remaining operating time. When the remaining driving distance is referred to as the remaining operating time, the change in cumulative pressure per unit operating time is set as the pressure increase rate. When predicting the remaining driving distance based on accumulated pressure and the rate of pressure increase, the accumulated pressure (lifespan threshold) at which the component's lifespan is assumed to be exhausted is determined experimentally in advance. The aging degree of the component is calculated based on the ratio of the current accumulated pressure to the lifespan threshold (current accumulated pressure / lifespan threshold × 100). The rate of aging (the change in aging degree per unit driving distance) is calculated based on the rate of pressure increase. The remaining driving distance until the aging degree reaches 100 is calculated.

[0064] The location determination unit 304 determines, for example, the location of the vehicle when the internal combustion engine is cold-started (i.e., assuming the vehicle is parked for an extended period) by utilizing location information from the Global Positioning System. The location storage unit 305 stores the location determined by the location determination unit 304.

[0065] The storage location determination unit 306 determines the storage location of the vehicle in a given usage environment based on the location stored in the location storage unit 305. Specifically, since a vehicle is likely to be parked in the same location for an extended period, that location is designated as the storage location if the location stored in the location storage unit 305 is consistent multiple times. The storage location storage unit 307 stores the storage location determined by the storage location determination unit 306.

[0066] The deviation calculation unit 308 calculates the deviation between the latest value and the previous value of the storage location stored in the storage location storage unit 307. The most recently determined storage location is the latest value, and the storage location determined before the latest value is the previous value. Furthermore, the deviation can be any indicator that can evaluate the correlation between the latest value and the previous value, and the magnitude of the deviation is determined based on the difference between the latest value and the previous value or the consistency rate between the latest value and the previous value. If the user of the vehicle changes, the storage location will naturally also change. That is, a significant change in the storage location indicates a change in the user of the vehicle.

[0067] In the life prediction device 300, when the deviation between the latest value of the storage location calculated by the deviation calculation unit 308 and the previous value of the storage location exceeds a threshold, the life prediction unit 303 calculates the pressure increase rate based solely on the operating history accumulated since the latest value of the storage location was determined. That is, before and after a change in vehicle usage conditions, the rate of aging of parts may change significantly. Since it is difficult to accurately predict the remaining driving distance if the changed rate of aging is not considered, the life prediction device 300 separates the operating history accumulated before and after the change in vehicle usage conditions, and calculates the pressure increase rate solely based on the operating history accumulated after the change in vehicle usage conditions. To accurately correlate changes in vehicle usage conditions with changes in storage location, a threshold is experimentally determined in advance. Furthermore, regardless of changes in vehicle usage, the cumulative pressure is the sum of the loads applied to the parts from the time they were assembled on the vehicle (from the time they were new) until the present. It will not decrease or disappear due to changes in vehicle usage. Therefore, it is necessary to calculate it based on the entire operating history.

[0068] Therefore, in the life prediction device 300, when the deviation between the latest value at the storage location and the previous value at the storage location exceeds a threshold, the pressure increase rate is calculated only based on the accumulated operating history since the latest value at the storage location was determined. Furthermore, the accumulated pressure is calculated based on the operating history before and after the latest value at the storage location was determined.

[0069] like Figure 6As shown, the life prediction method M300 implemented by the life prediction device 300 includes an operation history accumulation process S301, a location determination process S302, a location storage process S303, a storage location determination process S304, a storage location storage process S305, a deviation calculation process S306, and a life prediction process S307. Between the operation history accumulation process S301 and the life prediction process S307, there is also a location determination process S302, a location storage process S303, a storage location determination process S304, a storage location storage process S305, and a deviation calculation process S306, which is the main difference compared to previous methods.

[0070] In the operation history accumulation process S301, the operation history accumulation unit 302 accumulates the operation history of the parts constituting the vehicle. In the position determination process S302, the position determination unit 304 determines the position of the vehicle. In the position storage process S303, the position storage unit 305 stores the position determined in the position determination process S302. In the position determination process S302, the position of the internal combustion engine installed in the vehicle when it is cold-started is determined.

[0071] In the storage location determination procedure S304, the storage location determination unit 306 determines the vehicle's storage location based on the location stored in the location storage procedure S303. In the storage location storage procedure S305, the storage location storage unit 307 stores the storage location determined in the storage location determination procedure S304. Furthermore, in the storage location determination procedure S304, if the location stored in the location storage procedure S303 is consistent multiple times, that location is designated as the storage location.

[0072] In the deviation calculation step S306, the deviation calculation unit 308 calculates the deviation between the latest value of the storage location stored in the storage location storage program S305 and the previous value of the storage location. Furthermore, if the storage location is initially determined and there is no previous value, it is determined that there is no deviation in the deviation calculation step S306.

[0073] In the life prediction process S307, the life prediction unit 303 calculates the cumulative pressure and pressure increase rate of the part based on the operating history accumulated in the operating history accumulation process S301, and predicts the remaining travel distance of the part until its life is exhausted based on the cumulative pressure and pressure increase rate. However, if the deviation between the latest value of the storage location calculated by the deviation calculation process S306 and the previous value of the storage location is above a threshold, the pressure increase rate is calculated only based on the operating history accumulated after the latest value of the storage location was determined. Furthermore, if the deviation between the latest value of the storage location calculated by the deviation calculation process S306 and the previous value of the storage location is below a threshold, not only the operating history accumulated after the latest value of the storage location was determined is used, but also the operating history accumulated before the latest value of the storage location was determined is used in the calculation of the pressure increase rate.

[0074] Therefore, according to the life prediction device 300 and the life prediction method M300 implemented by the life prediction device 300, since the operation history accumulated before the change of vehicle usage conditions is not used in the calculation of the pressure increase rate, but only the operation history accumulated after the change of vehicle usage conditions is used to calculate the pressure increase rate, the remaining driving distance until the end of the component life can be predicted more accurately than before.

[0075] [Fourth Implementation]

[0076] like Figure 7 As shown, the life prediction device 400 according to the fourth embodiment is composed of a portion of the functions of the control device 401, including an operation history accumulation unit 402, a life prediction unit 403, and a change detection unit 404. The control device 401 is, for example, an engine control unit having a central computing processing unit and a storage area.

[0077] The operating history accumulation unit 402 accumulates the operating history of the parts that make up the vehicle. The operating history is the time-dependent change of various detection values ​​(e.g., outdoor temperature, vehicle travel distance, vehicle position, coolant temperature of the internal combustion engine installed in the vehicle, engine speed, and / or engine load) that are factors that cause the parts to age.

[0078] The life prediction unit 403 calculates the cumulative pressure and pressure increase rate on the component based on the operating history accumulated in the operating history accumulation unit 402, and predicts the remaining driving distance of the component until its lifespan is exhausted based on the cumulative pressure and pressure increase rate. The cumulative pressure is the sum of the loads applied to the component from the time it was assembled on the vehicle (from a new state) until the present. The pressure increase rate (the change in cumulative pressure per unit driving distance) is the rate at which the component ages. The life prediction unit 403 preferably informs the vehicle user or manager of the remaining driving distance. It may also warn the user or manager to perform maintenance as soon as possible if the remaining driving distance is determined to be low or zero (i.e., the component's lifespan is completely exhausted). Furthermore, the remaining driving distance can also be referred to as the remaining operating time. When the remaining driving distance is referred to as the remaining operating time, the change in cumulative pressure per unit operating time is set as the pressure increase rate. When predicting the remaining driving distance based on accumulated pressure and the rate of pressure increase, the accumulated pressure (lifespan threshold) at which the component's lifespan is assumed to be exhausted is determined experimentally in advance. The aging degree of the component is calculated based on the ratio of the current accumulated pressure to the lifespan threshold (current accumulated pressure / lifespan threshold × 100). The rate of aging (the change in aging degree per unit driving distance) is calculated based on the rate of pressure increase. The remaining driving distance until the aging degree reaches 100 is calculated.

[0079] The alteration detection department 404 detects alterations to the vehicle registration plate installed on the vehicle. Specifically, it detects alterations when the vehicle registration plate is removed from the vehicle or when the vehicle registration number recorded on the plate is changed. For example, it detects the removal of the vehicle registration plate by using a sensor that detects its installation or removal, and it detects changes to the vehicle registration number by using a camera that monitors changes to the vehicle registration number. If the vehicle's user changes, the vehicle registration plate will also be changed. In other words, an altered vehicle registration plate means a change in the vehicle's user.

[0080] In the life prediction device 400, when a change in vehicle registration number is detected by the change detection unit 404, the life prediction unit 403 calculates the pressure increase rate based solely on the operating history accumulated since the change in vehicle registration number was detected. That is, the rate of aging of parts can change significantly before and after a change in vehicle usage conditions. Since it is difficult to accurately predict the remaining driving distance without considering the changes in the rate of aging, the life prediction device 400 separates the operating history accumulated before and after the change in vehicle usage conditions, calculating the pressure increase rate only based on the operating history accumulated after the change in vehicle usage conditions. Furthermore, regardless of changes in vehicle usage conditions, the accumulated pressure is the sum of the loads applied to the parts from the time the parts were assembled into the vehicle (from a new state) until the present. It does not decrease or disappear due to changes in vehicle usage conditions; therefore, it is necessary to calculate it based on the entire operating history.

[0081] Therefore, in the life prediction device 400, when a change to the vehicle registration number is detected, the pressure increase rate is calculated solely based on the accumulated operating history since the change was detected. Furthermore, the accumulated pressure is calculated based on the operating history before and after the change was detected.

[0082] like Figure 8 As shown, the life prediction method M400 implemented by the life prediction device 400 includes an operation history accumulation process S401, a change detection process S402, and a life prediction process S403. The change detection process S402 is added between the operation history accumulation process S401 and the life prediction process S403, which is the main difference compared to previous methods.

[0083] In the operation history accumulation process S401, the operation history accumulation unit 402 accumulates the operation history of the parts constituting the vehicle. In the change detection process S402, the change detection unit 404 detects changes to the vehicle registration plate installed on the vehicle. The change detection process S402 detects changes to the vehicle registration plate when it is removed from the vehicle or when the vehicle registration number recorded on the vehicle registration plate is changed.

[0084] In the life prediction process S403, the life prediction unit 403 calculates the cumulative pressure and pressure increase rate of the part based on the operating history accumulated in the operating history accumulation process S401, and predicts the remaining driving distance of the part until its life is exhausted based on the cumulative pressure and pressure increase rate. However, if a change to the vehicle registration number is detected in the change detection process S402, the pressure increase rate is calculated only based on the operating history accumulated after the change to the vehicle registration number was detected. On the other hand, if no change to the vehicle registration number is detected in the change detection process S402, the calculation of the pressure increase rate uses all the operating history accumulated from when the part was assembled on the vehicle (from a new product state) until the present.

[0085] Therefore, according to the life prediction device 400 and the life prediction method M400 implemented by the life prediction device 400, since the operation history accumulated before the change of vehicle usage conditions is not used in the calculation of the pressure increase rate, but only the operation history accumulated after the change of vehicle usage conditions is used to calculate the pressure increase rate, the remaining driving distance until the end of the component life can be predicted more accurately than before.

[0086] Furthermore, in the aforementioned embodiments, although all processing is performed solely by control devices 101, 201, 301, and 401, for example, the remaining driving distance can be predicted using a computer located in a different location from the vehicle based on various detection values ​​obtained on the vehicle, and the predicted remaining driving distance can be sent to the vehicle. That is, it is not necessary to complete all processing on the vehicle.

[0087] As described above, according to the present invention, when the usage conditions of a vehicle change, the total operating history of the vehicle before and after the change in usage conditions is used when calculating the cumulative pressure, but only the operating history after the change in usage conditions is used when calculating the pressure increase rate. Therefore, even if the rate of aging of parts changes before and after the change in usage conditions, the remaining driving distance until the end of the part's lifespan can be accurately predicted.

[0088] This application is based on Japanese Patent Application No. 2020-158724, filed on September 23, 2020, the contents of which are incorporated herein by reference.

[0089] Industrial availability

[0090] The life prediction device and method disclosed herein are useful in that they can make more accurate predictions based on operating history compared to the past.

[0091] Explanation of reference numerals in the attached figures

[0092] 100, 200, 300, 400 lifespan prediction devices

[0093] 101, 201, 301, 401 control devices

[0094] 102, 202, 302, 402 Operational History Accumulation Department

[0095] Life Prediction Departments 103, 203, 303, and 403

[0096] 104 Using the domain frequency calculation unit

[0097] 105. Use of domain frequency storage unit

[0098] 106, 208, 308 Deviation Calculation Unit

[0099] 204, 304 Location Determination Section

[0100] Location storage units 205 and 305

[0101] 206 Basic Operating Route Determination Department

[0102] 207 Basic Operating Route Storage Department

[0103] 306 Storage Location Determination Department

[0104] 307 Storage Area

[0105] 404 Change Inspection Department

Claims

1. A lifespan prediction device, comprising: The operational history accumulation department accumulates the operational history of the parts that make up the vehicle. The life prediction unit calculates the cumulative pressure and pressure increase rate on the component based on the operating history accumulated in the operating history accumulation unit, and predicts the remaining travel distance until the component reaches the end of its lifespan based on the cumulative pressure and the pressure increase rate. The domain frequency calculation unit calculates the usage domain frequency of the internal combustion engine based on its rotational speed and load within the vehicle. The usage domain frequency storage unit stores the usage domain frequency calculated in the usage domain frequency calculation unit, and... The deviation calculation unit calculates the deviation between the latest value of the usage domain frequency stored in the usage domain frequency storage unit and the previous value of the usage domain frequency. If the deviation between the latest value of the usage domain frequency calculated by the deviation calculation unit and the previous value of the usage domain frequency is above a threshold, the life prediction unit calculates the pressure increase rate based solely on the operating history accumulated after the latest value of the usage domain frequency was calculated.

2. The lifetime prediction device as described in claim 1, further comprising: The location determination unit determines the position of the vehicle. A location storage unit that stores the location determined by the location determination unit. The usage environment determination unit determines the usage environment of the vehicle based on the location stored in the location storage unit, and... The usage environment storage unit stores the usage environment determined by the usage environment determination unit; The deviation calculation unit calculates the deviation between the latest value of the usage environment stored in the usage environment storage unit and the previous value of the usage environment. If the deviation between the latest value of the operating environment calculated by the deviation calculation unit and the previous value of the operating environment is greater than or equal to a threshold, the life prediction unit calculates the pressure increase rate based solely on the operating history accumulated since the latest value of the operating environment was calculated.

3. The lifespan prediction device as described in claim 2, characterized in that, The usage environment determination unit determines the vehicle's operating route based on the location stored in the location storage unit, and sets the operating route as the usage environment if the operating route is consistent multiple times.

4. The lifespan prediction device as described in claim 2, characterized in that, The position determination unit determines the position of the internal combustion engine installed in the vehicle when it is cold-started. If the location stored in the location storage unit is consistent multiple times, the usage environment determination unit sets that location as the usage environment.

5. The lifetime prediction device as claimed in claim 1, further comprising: The alteration inspection department detects alterations to the vehicle registration plate installed on the vehicle. When the change detection unit detects a change to the vehicle registration plate, the life prediction unit calculates the pressure increase rate based solely on the accumulated operating history since the change to the vehicle registration plate was detected.

6. A lifespan prediction method, comprising: The operational history accumulation process accumulates the operational history of the components that make up the vehicle. The lifespan prediction step calculates the cumulative pressure and pressure increase rate on the component based on the operating history accumulated in the operating history accumulation step, and predicts the remaining travel distance until the component reaches the end of its lifespan based on the cumulative pressure and the pressure increase rate. The domain frequency calculation step calculates the usage domain frequency of the internal combustion engine based on its rotational speed and load within the vehicle. The domain frequency storage step stores the domain frequency calculated in the domain frequency calculation step, and... The deviation calculation step calculates the deviation between the latest value of the usage domain frequency stored in the usage domain frequency storage step and the previous value of the usage domain frequency; In the lifespan prediction step, if the deviation between the latest value of the usage domain frequency calculated in the deviation calculation step and the previous value of the usage domain frequency is above a threshold, the pressure increase rate is calculated only based on the operating history accumulated after the latest value of the usage domain frequency is calculated.

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