JP2020192969A - Traction performance evaluation system and four-wheel-drive vehicle - Google Patents

Abstract

To provide a traction performance evaluation system capable of correctly evaluating the traction performance of a vehicle, and a four-wheel-drive vehicle.SOLUTION: A traction performance evaluation system 100 includes external information acquisition means 311 for acquiring external information on a disturbance factor which gives influence on a condition of a road surface on which an own vehicle 1 travels, slip rate calculation means 313 for calculating a slip rate of a tire on the basis of travel information indicating a travel state of the vehicle, and traction performance evaluation means 623 for evaluating the traction performance of the vehicle on the basis of a reference slip rate corresponding to the external information and the slip rate calculated by the slip rate calculation means 313.SELECTED DRAWING: Figure 1

Description

The present invention relates to a traction performance evaluation system and a four-wheel drive vehicle.

Conventionally, a traction performance evaluation system for suppressing slippage of vehicle tires is known (see, for example, Patent Document 1).

The traction performance evaluation system described in Patent Document 1 includes a control unit that controls the transmission torque of the driving force transmission device, and this control unit calculates a transmission torque command value based on the traveling state of the vehicle. The calculation means, the energy calculation means that calculates the energy value obtained by integrating the transmission torque and the differential rotation speed between the two relative rotatable members at predetermined sampling times, and the energy cumulative value that accumulates the energy values are calculated. It has an energy cumulative value calculation means and a correction means for correcting the transmission torque command value calculated by the transmission torque command value calculation means based on the acquired correction torque. With this configuration, it is said that the command torque can be corrected without being affected by the time-dependent change of the driving force transmission device.

JP-A-2009-09221

By the way, the traction performance of a vehicle is affected not only by changes with time of the driving force transmission device but also by external factors such as tire type, air pressure, road surface condition and the like. Therefore, in the traction performance evaluation system described in Patent Document 1, It may not be possible to accurately evaluate traction performance considering the effects of external factors.

Therefore, an object of the present invention is to provide a traction performance evaluation system and a four-wheel drive vehicle capable of more accurately evaluating the traction performance of a vehicle.

In order to achieve the above object, the present invention is based on an external information acquisition means for acquiring external information on a disturbance factor affecting the condition of the road surface on which the target vehicle travels, and traveling information indicating the traveling state of the target vehicle. The traction performance of the target vehicle is evaluated based on the slip ratio calculating means for calculating the slip ratio of the tire, the reference slip ratio of the tire according to the external information, and the slip ratio calculated by the slip ratio calculating means. Provided is a traction performance evaluation system provided with a traction performance evaluation means.

Further, in order to achieve the above object, the present invention includes a main drive wheel in which the driving force of the driving source is constantly transmitted, an auxiliary driving wheel in which the driving force of the driving source is transmitted according to the vehicle state, and the above. A driving force transmitting device interposed in a driving force transmitting path to the auxiliary driving wheels and a control device for controlling the driving force transmitting device according to the vehicle state are provided, and the control device is used for traction performance evaluation as described above. Provided is a four-wheel drive vehicle capable of acquiring an evaluation result of the traction performance evaluation means of the system and controlling a driving force transmission device based on the evaluation result.

According to the traction performance evaluation system and the four-wheel drive vehicle according to the present invention, the traction performance of the vehicle can be evaluated more accurately.

It is a block diagram which shows an example of the whole structure of the traction performance evaluation system which concerns on this embodiment. It is a block diagram which shows the schematic structure example of the own vehicle which concerns on this embodiment. It is a block diagram which shows the structural example of the control device which concerns on this embodiment. This is an example of the collected data collected by the information collection server. It is a block diagram which shows the configuration example of the information collection server which concerns on this Embodiment. It is a table which shows an example of the statistical map which shows the relationship between a command torque and a slip ratio. This is an example of a graph showing the transition of rank information with the passage of time. This is an example of a statistical graph showing the relationship between the slip rate and the elapsed time. This is an example of an IT characteristic map showing the relationship between the command current value and the command torque. It is a flowchart which shows an example of the operation of the control part of own vehicle and an information collection server.

[Embodiment]
Embodiments of the present invention will be described with reference to FIGS. 1 to 10. It should be noted that the embodiments described below are shown as suitable specific examples for carrying out the present invention, and there are some parts that specifically exemplify various technically preferable technical matters. , The technical scope of the present invention is not limited to this specific aspect.

FIG. 1 is a configuration diagram showing an example of an overall outline of a traction performance evaluation system according to an embodiment of the present invention.

As shown in FIG. 1, the traction performance evaluation system 100 enables communication with the own vehicle 1 to be evaluated, a plurality of other vehicles 5, and the own vehicle 1 and the plurality of other vehicles 5 via the wireless communication network 90. It is composed of a connected external device 9.

In the present embodiment, for convenience of explanation, the own vehicle 1 and the plurality of other vehicles 5 are distinguished from each other. However, even if the plurality of other vehicles 5 are the evaluation targets, the own vehicle 1 and the plurality of other vehicles 5 are evaluated. The vehicle type, model year, model, etc. of the 5 are arbitrary and are not particularly limited. The own vehicle 1 and a plurality of other vehicles 5 correspond to the "target vehicle" in the present invention.

The external device 9 is composed of an information collection server 6 that collects vehicle information of the own vehicle 1 and a plurality of other vehicles 5, a weather information server 81, a road information server 82, and a GPS 83.

The meteorological information server 81 is a server that provides meteorological information all over Japan acquired from meteorological stations in various places. The road information server 82 is a server that provides information indicating a road condition (for example, a paved road) according to the current position where the vehicle travels. The weather information provided by the weather information server 81 and the road information provided by the road information server 82 are examples of disturbance factors that affect the condition of the road surface on which the vehicle travels.

FIG. 2 is a configuration diagram showing a schematic configuration example of the own vehicle 1 according to the present embodiment. The own vehicle 1 is a four-wheel drive that can change the distribution of the driving force from a four-wheel drive state in which the driving force is transmitted to the front wheels and the rear wheels to a two-wheel drive state in which the driving force is transmitted only to the front wheels. It is a car. The configuration of the own vehicle 1 described with reference to FIG. 2 is the same for the plurality of other vehicles 5.

As shown in FIG. 2, the own vehicle 1 includes an engine 11 as a drive source for generating a driving force (torque) for traveling, a transmission 12 for shifting the output of the engine 11, and an engine 11 shifted by the transmission 12. Front wheels 10L, 10R as a pair of left and right main driving wheels to which the driving force of the engine 11 is always transmitted, and rear wheels 20L, 20R as a pair of left and right auxiliary driving wheels to which the driving force of the engine 11 is transmitted according to the vehicle condition. And have.

Further, the own vehicle 1 differentially distributes the output of the engine 11 to the front wheels 10L and 10R and also differentially distributes the rotational force of the propeller shaft 14 to the rear wheels 20L and 20R and the front differential 13 that transmits the output to the propeller shaft 14. Rear differential 15, drive shafts 161, 162 on the left and right front wheels, drive shafts 171 and 172 on the left and right rear wheels, and a driving force transmission device 2 arranged between the propeller shaft 14 and the rear differential 15. And a control device 3 for controlling the driving force transmission device 2.

The control device 3 includes rotation speed sensors 101 to 104 that detect the rotation speeds of the left and right front wheels 10L and 10R and the left and right rear wheels 20L and 20R, an accelerator pedal sensor 105 for detecting the amount of depression of the accelerator pedal 110, and Various detection values including the detection value of the steering angle sensor 106 that detects the steering angle of the steering wheel 180 can be obtained directly from each sensor or from another control device of the own vehicle 1 (not shown) via an in-vehicle network such as CAN. It can be acquired, and a current is supplied to the driving force transmission device 2 based on these detected values and the like. The information indicated by the detected values obtained from the rotation speed sensors 101 to 104, the accelerator pedal sensor 105, and the steering angle sensor 106 is an example of the "running information" of the present invention. The details of the control device 3 will be described later.

The driving force transmission device 2 increases or decreases the driving force transmitted to the left and right rear wheels 20L and 20R according to the current supplied from the control device 3. Further, the driving force transmission device 2 includes a housing 21, a tubular output shaft 22 coaxially and coaxially supported with the housing 21, a multi-plate clutch 23 housed in the housing 21, and a multi-plate clutch 23. It has an actuator 24 for pressing. The multi-plate clutch 23 has a plurality of outer clutch plates 23a that rotate integrally with the housing 21 and a plurality of inner clutch plates 23b that rotate integrally with the output shaft 22, and receives the pressing force of the actuator 24 to receive the outer clutch plate 23a. And the inner clutch plate 23b are in frictional contact with each other.

FIG. 3 is a block diagram showing the configuration of the control device 3. FIG. 4 is a block diagram showing the configuration of the information collection server 6 of the external device 9.

As shown in FIG. 3, the control device 3 is composed of a communication unit 30 that transmits / receives information to / from a plurality of other vehicles 5 and an external device 9 via a wireless communication network 90, a CPU (arithmetic processing device), and peripheral circuits thereof. It has a control unit 31 configured, a storage unit 32 composed of storage elements such as ROM and RAM, and a current output circuit 33 for outputting a current to the actuator 24 of the driving force transmission device 2.

Further, the control device 3 has a display unit 41 that displays information output by the control unit 31, a travel information detection unit 42 that detects travel information indicating the travel state of the own vehicle 1, and a current position of the own vehicle 1. The position detection unit 43 is connected to the position detection unit 43.

The display unit 41 displays the information output from the control unit 31. The display unit 41 is, for example, a display such as a liquid crystal display or an organic EL, and may function as a display unit of a car navigation system, or may be provided on a console panel of a vehicle.

The traveling information detection unit 42 is composed of a plurality of sensors such as rotation speed sensors 101 to 104, an accelerator pedal sensor 105, and a steering angle sensor 106 that acquire parameters related to the traveling state of the own vehicle 1.

The position detection unit 43 acquires position information indicating the current position of the own vehicle 1, and is a GPS receiver that acquires the current position information (longitude, latitude, etc.) of the own vehicle 1 by using a satellite positioning system. Is.

The communication unit 30 is an electronic control device that transmits / receives information by communicating with a communication target other than the own vehicle 1 via the wireless communication network 90. The communication unit 30 is composed of a communication module such as a DCM (Data Communication Module).

The control unit 31 controls the driving force transmission device 2 by executing the program 320 stored in the storage unit 32. In addition to the program 320, the torque map 321 is stored in the storage unit 32. The torque map 321 shows, for example, the difference in front / rear wheel rotation speed, which is the difference between the average rotation speed of the left and right front wheels 10L and 10R and the average rotation speed of the left and right rear wheels 20L and 20R, the amount of depression of the accelerator pedal 110, and the steering angle. Map information for calculating the driving force to be distributed to the left and right rear wheels 20L and 20R is defined based on the vehicle speed and the vehicle speed.

The control unit 31 refers to the torque map 321 based on the vehicle traveling state, and calculates a command current according to the driving force to be distributed to the left and right rear wheels 20L and 20R. Then, a PWM signal is generated so that the current corresponding to this command current is output from the current output circuit 33 to the driving force transmission device 2.

The control unit 31 of the control device 3 includes an external information acquisition means 311, a position information acquisition means 312, a slip ratio calculation means 313, a command torque calculation means 314, a transmission means 315, a reception means 316, and a notification means 317. , And command torque correction means 318.

The external information acquisition means 311 estimates the road surface condition based on the weather information provided by the weather information server 81 of the external device 9. For example, when the weather information is sunny, the external information acquisition means 311 estimates that the road surface condition is dry, and when the weather information is rainy, it estimates that the road surface condition is wet. Further, the external information acquisition means 311 acquires information indicating a road condition (paved road or unpaved road) based on the road information provided by the road information server 82. The position information acquisition means 312 acquires the position information generated by the position detection unit 43.

The slip ratio calculating means 313 calculates the slip ratio based on the traveling information regarding the traveling state of the vehicle detected by the traveling information detecting unit 42. This slip ratio can be calculated based on, for example, each wheel speed detected through the rotational speed sensors 101 to 104 and an estimated vehicle body speed calculated based on these wheel speeds. Further, it may be calculated based on the difference in the number of rotations between the front wheels and the rear wheels.

The command torque calculation means 314 calculates the command torque to be transmitted by the driving force transmission device 2 based on the detection result of the travel information detection unit 42.

The transmission means 315 transmits information on the traction performance to the information collection server 6 by the communication unit 30. Communication unit that transmits the slip rate calculated by the slip rate calculation means 313, the command current value calculated by the command torque calculation means 314, vehicle information (vehicle ID, vehicle type, etc.), position information, road surface information, and weather information related to the own vehicle 1. Transmission data is generated based on 30, and the transmission data is transmitted to the information collection server 6 of the external device 9. This transmission data corresponds to a part of the collected data 60 collected by the information collection server 6.

FIG. 4 is a table showing an example of the collected data 60. As shown in FIG. 4, the collected data 60 includes a vehicle ID for identifying a vehicle, vehicle type information regarding the vehicle type of the vehicle, position information indicating the current position where the vehicle travels, and a road at the position indicated by the position information. It has the condition and road surface condition, the coefficient of friction calculated for each vehicle, the slip ratio and the command current value as items. The item of the collected data 60 is merely an example, and is not limited to this, and information such as the measurement date and time and the mileage may be set as the item.

The receiving means 316 receives the evaluation result 633 of the traction performance evaluation means 623 and the determination result of the deterioration progress determination means 625 from the information collection server 6 described later.

The notifying means 317 notifies the driver of the rank information as the evaluation result 633 obtained by the receiving means 316. The notification means 317 notifies the driver by displaying on the display unit 41 maintenance information indicating, for example, tire replacement or deterioration of the vehicle, as cautionary information that the own vehicle 1 is slippery. As a result, the driver can be encouraged to drive safely.

Further, the notification means 317 notifies the driver that the rank information has suddenly decreased as a determination result determined by the deterioration progress determination means 625. As a result, it is possible to notify the driver of the abnormality, so that it is possible to promote safe driving or provide the driver with information that repair is necessary.

The command torque correction means 318 calculates the command current value of the control current to be supplied to the driving force transmission device 2 based on the command torque, and obtains the calculated command current value by the traction performance evaluation means 623 of the information collection server 6. Correct based on the obtained rank information. The details of the command torque correction means 318 will be described later.

As shown in FIG. 5, the information collection server 6 calculates based on the communication unit 61 that transmits / receives information between the own vehicle 1 and the plurality of other vehicles 5 and the information collected via the communication unit 61. It has a control unit 62 that executes processing, and a storage unit 63 that stores a program 621 executed by the control unit 62. The information collection server 6 receives not only the transmission data transmitted by the transmission means 315 of the control unit 31 in the control device 3, but also the same data as the transmission data from the plurality of other vehicles 5, and collects the reception data. Collect as data 60.

The control unit 62 of the information collection server 6 extracts data from the receiving means 620 that receives the collected data 60 collected from the own vehicle 1 and the other vehicle 5 via the communication unit 61 and the collected data 60 under predetermined extraction conditions. Collected data extraction means 621, statistical map generation means 622 that generates statistical map 632 based on the extracted data extracted by collected data extraction means 621, and traction performance evaluation means 623 that evaluates traction performance based on statistical map 632. The storage means 624, the deterioration progress determination means 625 for determining the deterioration progress of the traction performance, the evaluation result 633 of the traction performance evaluation means 623, and the determination result of the deterioration progress determination means 625 are transmitted to the vehicle. It has a transmission means 626 and an aged deterioration data generation means 627 that generates aged deterioration data based on the data stored in the storage unit 63.

The collected data extraction means 621 extracts data from the collected data 60 that has the same vehicle type and position information as the own vehicle 1 and the same road surface condition. That is, the vehicle of the same vehicle type that has traveled at the same position as the position where the own vehicle 1 travels by the collected data extraction means 621 is in the same environment as the own vehicle 1 (for example, a paved road). Information on the plurality of other vehicles 5 is extracted from the collected data 60. Since the statistical map 632 is generated based on the extracted data extracted in this way, the accuracy of the evaluation result 633 by the traction performance evaluation means 623 is improved. The extraction conditions of the collected data extracting means 621 are not limited to this, and the collected data extracting means 621 may extract only the data of the same vehicle type as the own vehicle 1, and extracts only the data of the same position as the own vehicle 1. You may.

FIG. 6 is a table showing an example of the statistical map 632. In the statistical map 632, the command torque and the slip ratio are associated with each other, and the horizontal axis represents the command torque and the vertical axis represents the slip ratio. The statistical map 632 is not limited to this as long as it is data that can evaluate the traction performance of the vehicle, and may be data in which the friction coefficient and the slip ratio are related, for example, the slip ratio and the vehicle speed. The data may be related to.

Statistical map 632 is set and the standard value O to a predetermined, first to fourth threshold _S 1 to S ₄ is. The standard value O is, for example, a value determined based on the performance evaluation of the vehicle at the time of shipment from the factory. The first to fourth threshold S ₁ to S ₄ maps the slip ratio and the command torque of the collected data 60 is a value determined by using a statistical method to the mapped data. The first to fourth threshold _S 1 to S ₄ is deviated from the standard value O by a predetermined value.

For the first and second threshold values S ₁ and S ₂ , the value of the slip ratio with respect to the command torque is larger than the standard value O, and the first threshold value S ₁ deviates from the standard value O more than the second threshold value S _2. There is. The third and fourth threshold S _3, S ₄ is larger than the value of the slip ratio is a standard value O for the command torque, the direction of the fourth threshold value S ₄ deviates from the standard value O than the third threshold value S ₃ doing.

Here, in a statistical map 632, an area larger than the slip rate is the first threshold value S ₁ and the first area A, a region surrounded by the first threshold value S ₁ and the second threshold S ₂ and second area B, the The area surrounded by the second threshold value S ₂ and the standard value O is defined as the third area C, the area surrounded by the third threshold value S ₁ and the standard value O is defined as the fourth area D, and the third threshold value S ₃ and the fourth threshold value S ₄ are defined. the region surrounded by a fifth area E, an area slip rate is smaller than the fourth threshold value S ₄ and the sixth area F. For example, when the value of the slip ratio corresponding to the command torque exists in the first area A, it means that the vehicle is in a slippery state, and when it exists in the sixth area F, the vehicle is hard to slip. It means being in a state.

The traction performance evaluation means 623 refers to the own vehicle 1 by comparing the slip ratio calculated by the slip ratio calculation means 313 and the command torque calculated by the command torque calculation means 314 with the statistical map 632 as the reference slip ratio. Evaluate traction performance. Specifically, the traction performance evaluation means 623 maps the calculation data of the slip ratio and the command torque to the statistical map 632, and sets the traction performance evaluation result 633 based on the area on the statistical map 632 in which the calculated data exists. Determine the rank information of.

This rank information is information ranked according to the traction performance of the own vehicle 1. For example, when the calculated data exists in the first area A of the statistical map 632, the rank A (slip level: slip level:) is used as the rank information. Large) is set, rank B (slip level: medium) is set when the calculated data exists in the second area B, and rank C (slip level: medium) is set when the calculated data exists in the third area C. Small) is set. In this way, the traction performance evaluation means 623 determines the slipperiness of the own vehicle 1 based on the statistical map 632 generated by the collected data 60 regarding the plurality of other vehicles 5, so that the traction performance of the own vehicle 1 is objective. Can be grasped.

The storage means 624 stores the statistical map 632 and the rank information as the evaluation result 633 of the traction performance evaluation means 623 in the storage unit 63.

The deterioration progress determination means 625 compares the current evaluation result 633 evaluated by the traction performance evaluation means 623 with the past evaluation result 633 stored in the storage means 624, and based on the comparison result, the target vehicle Determine the degree of deterioration of the traction performance of a certain own vehicle 1. That is, the deterioration progress determination means 625 determines the deterioration progress based on the fluctuation of the traction performance evaluation result 633 within a predetermined period. In the present embodiment, when the rank information as the evaluation result 633 is lowered by two ranks within a predetermined period, the deterioration progress determination means 625 determines that the traction performance has deteriorated.

FIG. 7 is an example of a graph showing the transition of rank information with the passage of time. FIG. 7 shows the transition of the rank information of any two vehicles for convenience of explanation, the transition of the rank information for one vehicle is shown by a solid line, and the transition of the rank information for the other vehicle is a two-dot chain line. It is shown by.

As shown in FIG. 7, in the case of one vehicle shown by a solid line, the time t ₂ at the present time when the own vehicle 1 is traveling and the time t ₁ at the past time point predetermined time before the current time. in the time point t ₃ between the rank information is decreased from C to B, rank information until time t ₂ the current is maintained in a state of B. Here, the predetermined time is set to, for example, 1 month to 6 months.

On the other hand, in the case of other vehicles indicated by the two-dot chain line, lowers the rank information from C at time t ₄ between times t ₂ the current and the time t ₁ of the past time point B, further time the current At t ₁ , the rank information is reduced from B to A.

Other vehicles aged deterioration degree determination means in 625, the past evaluation results Evaluation results 633 by the traction performance evaluation unit 623 at time t ₁ time in the past going back by a predetermined a predetermined time from the time t ₂ at the present time Set as 633. The past evaluation result 633 is acquired from the storage unit 63.

The aged deterioration degree determination means 625 compares the rank information C is a past evaluation result 633 at time t ₁ in the past time, and rank information A is the current evaluation result 633 at time t ₂ the current .. The aged deterioration progress determination means 625 transmits information indicating that there is a sudden change in the rank information to the own vehicle 1 via the transmission means 626 based on the comparison result that the rank information is lowered by two ranks. On the other hand, for one vehicle, since the rank information is lowered by only one rank, it is not determined that the deterioration is progressing rapidly.

The aging deterioration data generation means 627 generates aging deterioration data based on the accumulated data stored in the storage unit 63. This accumulated data includes, for example, a slip ratio calculated by the control unit 62 of the information collection server 6, a friction coefficient, an evaluation result, and the like, and is stored in the storage unit 63.

FIG. 8 is a graph showing an example of aged deterioration data showing the transition of the slip ratio with the passage of time. FIG. 8 is a graph showing changes in the slip rate over the past several years, with the vertical axis showing the slip rate and the horizontal axis showing the time. As shown in FIG. 8, it can be seen that the slip ratio increases with the passage of time. In other words, it is shown that the traction performance is gradually deteriorating.

This aging deterioration data visualizes the performance of the vehicle and improves convenience. For example, it is possible to indicate the tire replacement timing, the repair timing timing, and the evaluation value standard at the time of vehicle resale. In the above embodiment, the aged deterioration data is set to show the transition of the slip rate, but the present invention is not limited to this, and the transition of the rank information may be used.

A predetermined threshold value may be displayed on the graph of the aged deterioration data. As a result, when the slip rate that changes over time exceeds the threshold value, it is possible to notify the driver, for example, that it is time for repair or replacement.

Next, the command torque correction means 318 in the control unit 31 of the control device 3 described above will be described. The command torque correction means 318 is set with an IT characteristic map 322 in which the command torque T and the command current value I are related. FIG. 9 is an example of the IT characteristic map 322. The vertical axis of the IT characteristic map 322 shows the command torque T, and the horizontal axis shows the command current value I. As shown in FIG. 9, the target torque T ₀ obtained in the vehicle evaluation at the time of vehicle shipment is set in the IT characteristic map 322. The target torque T ₀ is set so that the command current value I increases as the absolute value of the command torque T increases.

The command torque correction means 319 calculates the command current value by comparing the calculated command torque with the IT characteristic map 322, and multiplies the calculated command current value by a correction coefficient according to the rank information. Correct the command current value. The correction coefficient can be obtained, for example, by referring to a correction coefficient map in which the rank information and the correction coefficient are related in advance. This correction coefficient is a value for correcting the deviation of the calculated data in the statistical map 632 from the standard value O. For example, when the rank information obtained from the calculated data is ranks A to C, the command torque correction means 319 multiplies the correction coefficient by the command current value to obtain an output torque T ₁ larger than the target torque T ₀ (FIG. 9). Two-dot chain line shown in).

Next, the processing content of the traction performance evaluation system 100 according to the present embodiment will be described with reference to FIG. FIG. 10 is a flowchart showing an example of processing of the control unit 31 of the control device 3 and the control unit 62 of the information collection server 6 in the own vehicle 1.

First, the control unit 31 acquires the position information indicating the current position of the own vehicle 1 generated by the position detection unit 24 (step S10), and the road surface condition is based on the weather information acquired from the weather information server 81 of the external device 9. (Dry, wet, snow) is estimated, and the road condition is estimated based on the road information (paved, unpaved) acquired from the road information server 82 (step S11).

Next, the control unit 31 calculates the slip ratio and the command torque based on the travel information indicating the travel state of the own vehicle 1 acquired from the travel information detection unit 42 (steps S12 and S13), and the calculated slip ratio and the command. The torque and vehicle information (vehicle ID, vehicle type, vehicle speed, etc.) related to the own vehicle 1 are transmitted to the information collection server 6 of the external device 9 (step S14).

Next, the control unit 31 receives rank information or information indicating that there is a degree of deterioration progress from the information collection server 6 (step S15). Then, the control unit 31 notifies the driver of the caution information according to the rank information (step S16), and corrects the command torque according to the rank information (step S17). As a result, the processing of the control unit 31 of the own vehicle 1 is completed.

The control unit 62 of the information collection server 6 receives the collected data 60 from the own vehicle 1 and the plurality of other vehicles 5 (step S20), generates a statistical map 632 based on the collected data 60 (step S21), and generates the statistical map 632. The resulting statistical map 632 is stored in the storage unit 63 (step S22).

Next, the control unit 62 acquires the rank information of the own vehicle 1 based on the slip ratio and the command torque received from the control unit 31 of the own vehicle 1 in step S20 and the generated statistical map 632 (step S23). .. Then, when the rank information is rank A or B (step S25: Yes), the rank information is transmitted to the control unit 31 of the own vehicle 1 (step S26). On the other hand, if the rank information is not rank A or B (step S25: No), the process proceeds to step S27 as it is.

In step S27, the control unit 62 determines whether or not the rank information has dropped by two ranks (step S27). In this process, the deterioration progress determination means 625 determines based on the comparison between the rank information as the past evaluation result 633 and the rank information as the current evaluation result 633.

When it is determined that the rank information has dropped by two ranks (step S27: Yes), information indicating that the rank information has dropped sharply is transmitted to the control unit 31 of the own vehicle 1 (step S28). On the other hand, if it is not determined that the rank information has dropped by two ranks (step S27: No), aged deterioration data is generated based on the data accumulated in the storage unit 63 (step S29), and the process ends as it is. To do.

(Actions and effects of embodiments)
According to the embodiment described above, the traction performance is evaluated based on the slip ratio calculated by the own vehicle 1 and the statistical map 632 as a reference slip ratio according to external information such as the road surface condition and the road condition. Therefore, it is possible to evaluate the traction performance in consideration of external factors. As a result, the traction performance of the own vehicle 1 can be accurately grasped.

Further, according to the present embodiment, the driver is notified of the rank information in which the traction performance is ranked based on the statistical map 632 of the plurality of other vehicles 5 traveling in the same vehicle type and the same position as the own vehicle 1. It is possible to give the driver objective information indicating the slipperiness of the tire. As a result, the driver can be encouraged to drive safely, and an accident can be prevented.

Further, in the above embodiment, only the control unit 31 of the own vehicle 1 among the own vehicle 1 and the plurality of other vehicles 5 has been described, but the plurality of other vehicles 5 also have a control unit having the same configuration to provide traction performance. It is possible to evaluate. In this case, if the traction performance of any of the plurality of other vehicles 5 is ranked in rank A, the own vehicle 1 may be configured to detect this information. As a result, it is possible to prevent an accident by notifying the driver of the own vehicle 1 of the existence of a dangerous vehicle that is slippery in the surroundings.

In addition, even for the same vehicle model, the slipperiness of the vehicle may vary due to factors such as tire type, air pressure, and deterioration of other parts, but in the conventional driving force transmission device, the command is given in consideration of these factors. Since the torque is not controlled, it was difficult to accurately grasp the traction performance. Therefore, in the present embodiment, information on a plurality of other vehicles 5 traveling in the same vehicle type as the own vehicle 1 and in the same environment (for example, traveling in the same position as the own vehicle 1 and having the same road surface condition) is used. By evaluating the traction performance based on the objective data of the statistical map 632, it is possible to accurately grasp the traction performance of the own vehicle 1 without considering the above factors in each vehicle.

Further, in the above embodiment, since the control unit 62 includes the deterioration progress determination means 625 for determining the progress of deterioration of the traction performance, the traction performance of the past own vehicle 1 and the traction of the current own vehicle 1 are provided. It is possible to grasp the degree of deterioration of the own vehicle 1 by comparing it with the performance. As a result, the driver is encouraged to drive safely, or the driver is notified in advance of the repair time, so that an accident can be prevented. That is, safety is improved.

(Additional note)
Although the present invention has been described above based on the embodiments, these embodiments do not limit the invention according to the claims. It should also be noted that not all combinations of features described in the embodiments are essential to the means for solving the problems of the invention.

In the above embodiment, only the control unit 31 of the own vehicle 1 among the own vehicle 1 and the plurality of other vehicles 5 has been described, but the plurality of other vehicles 5 also have a control unit having the same configuration and can change the state of the tires. It shall be possible to judge. In this case, if there is a vehicle whose rank information is rank A or rank B among the plurality of other vehicles 5, the own vehicle 1 may be configured to detect this information. As a result, it is possible to prevent an accident by notifying the driver of the own vehicle 1 of the existence of a dangerous vehicle that is slippery in the surroundings.

Further, in the above embodiment, the control unit 62 of the information collection server 6 determines the rank information by the traction performance evaluation means 623, but the control unit 31 of the own vehicle 1 may determine the rank information. .. Further, in the above embodiment, the control unit 62 of the information collection server 6 detects a sudden change in the rank information by the deterioration progress determination means 625, but the control unit 31 of the own vehicle 1 detects the rank information. You may try to detect a sudden change. That is, the traction performance evaluation means 623 and the deterioration progress determination means 625 may be mounted on the control unit 31 of the control device 3 of the own vehicle 1 or may be mounted on the control unit 62 of the information collection server 6.

Further, in the present invention, the information collection server 6 of the external device 9 is not an indispensable component. That is, in the above embodiment, the information collection server 6 of the external device 9 generates a statistical map 632 based on the collected data 60, and evaluates the traction performance or determines the degree of deterioration based on the statistical map 632. The control unit 31 of the own vehicle 1 may perform all of these processes.

Further, in the above embodiment, the threshold values set in the statistical map 632 are the first and second threshold values S ₁ and S ₂ , but the number of threshold values is not limited to this, for example, the threshold value is It may be three or six.

Further, in the above embodiment, the control unit 3 acquires various sensor detection values, but acquires the calculation values calculated by another control device (not shown) of the own vehicle 1 via an in-vehicle network such as CAN. You may try to do it.

1 ... own vehicle 2 ... driving force transmission device 3 ... control device 5 ... other vehicle 6 ... information collection server 9 ... external device 81 ... weather information server 82 ... road information server 100 ... traction performance evaluation system 311 ... external information acquisition means 312 ... Position information acquisition means 313 ... Slip rate calculation means 314 ... Command torque calculation means 317 ... Notification means 318 ... Command torque correction means 623 ... Traction performance evaluation means 625 ... Deterioration progress determination means 627 ... Aged deterioration data generation means 632 ... Statistics map

Claims (13)

External information acquisition means for acquiring external information about disturbance factors that affect the condition of the road surface on which the target vehicle travels,
A slip rate calculating means for calculating a tire slip rate based on running information indicating the running state of the target vehicle, and
A traction performance evaluation means for evaluating the traction performance of the target vehicle based on the reference slip rate according to the external information and the slip rate calculated by the slip rate calculation means is provided.
Traction performance evaluation system. The traction performance evaluation means evaluates the traction performance based on the slip ratio of tires of a plurality of vehicles of the same vehicle type as the target vehicle.
The traction performance evaluation system according to claim 1. The traction performance evaluation means evaluates the state of tires based on the slip ratios of a plurality of vehicles of the same model as the target vehicle.
The traction performance evaluation system according to claim 1. The target vehicle can communicate with an external device that collects driving information from the plurality of vehicles.
The external device has the traction performance evaluation means, and transmits the evaluation result evaluated by the traction performance evaluation means to the target vehicle.
The traction performance evaluation system according to any one of claims 1 to 3. The target vehicle has the traction performance evaluation means.
The traction performance evaluation system according to any one of claims 1 to 3. The external information includes at least one of information regarding weather information and road information.
The traction performance evaluation system according to claim 1. A notification means for notifying the driver of the target vehicle of the evaluation result of the traction performance evaluation means is provided.
The traction performance evaluation system according to any one of claims 1 to 6. A storage means for storing the evaluation results of the traction performance evaluation means and
The current evaluation result evaluated by the traction performance evaluation means is compared with the past evaluation result stored in the storage means, and the degree of deterioration of the traction performance of the target vehicle is determined based on the comparison result. Further equipped with a deterioration progress determination means,
The traction performance evaluation system according to claim 1. The evaluation result of the traction performance evaluation means is rank information ranked according to the traction performance of the target vehicle.
Further provided is a notification means for notifying the driver of the target vehicle when the deterioration progress determination means determines that the rank information has deteriorated within a predetermined time.
The traction performance evaluation system according to claim 8. The target vehicle can communicate with an external device that collects driving information from the plurality of vehicles.
The external device has the deterioration progress determination means.
The deterioration progress determination means transmits information indicating the deterioration progress determined based on the evaluation results of the traction performance evaluation means to the plurality of vehicles to the target vehicle.
The traction performance evaluation system according to claim 8 or 9. The deterioration progress determination means determines the deterioration progress of the traction performance based on the evaluation results of a plurality of vehicles of the same vehicle type as the target vehicle.
The traction performance evaluation system according to any one of claims 8 to 10. The target vehicle has the deterioration progress determination means.
The traction performance evaluation system according to claim 8 or 9. Main drive wheels to which the driving force of the driving source is constantly transmitted, and auxiliary driving wheels to which the driving force of the driving source is transmitted according to the vehicle state.
A driving force transmitting device interposed in the driving force transmitting path to the auxiliary driving wheel, and
A control device that controls the driving force transmission device according to the vehicle state is provided.
The control device can acquire the evaluation result of the traction performance evaluation means in the traction performance evaluation system according to any one of claims 1 to 12, and controls the driving force transmission device based on the evaluation result. Four-wheel drive vehicle.

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