JP2012083967A - Driving evaluation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To calculate and display a driving evaluation value by an appropriate method even in a case where the degree of estimation accuracy of vehicle behavior decreases due to GPS reception state.SOLUTION: A driving stability evaluation device obtains a GPS reception signal (S101), sets a reception time for the GPS reception signal (S102), calculates the speed of the vehicle (S103), also calculates the estimated value of the vehicle behavior based on the current position of the vehicle, reception time, and vehicle speed (S104). Based on the updated time of the current position of the vehicle obtained from the reception time, the degree of accuracy in the estimated value of the behavior is calculated (S105). Then, based on the estimated value of the behavior and the degree of accuracy in the estimated value of the behavior, an evaluation value concerning the running of the vehicle is calculated (S107) and the evaluation value is displayed (S108).

Description

  The present invention relates to a driving evaluation apparatus that evaluates the driving stability of a vehicle by a driver based on GPS reception information, and promotes driving improvement by feeding back an evaluation result to the driver.

  2. Description of the Related Art Conventionally, a technique is known in which speed and acceleration are calculated based on the position and time of GPS reception information, and a diagnostic index relating to a driver's driving characteristics is generated and output (see, for example, Patent Document 1).

JP 2008-276316 A

  In the above prior art, when the GPS reception condition is bad, a delay occurs in the reception time of the GPS signal, and the detection accuracy of the current position of the moving body is lowered. As a result, the calculation accuracy of the speed and acceleration of the moving body is lowered. Although the evaluation accuracy of driving stability evaluated in such a situation is lowered, since it is not distinguished from the case where there is no delay in the reception time of the GPS signal, sufficient reliability for the driving evaluation device of the driver is obtained. I can't.

  The present invention has been made in view of such a conventional problem, and the object thereof is related to the driving of the driver by an appropriate method even when the calculation accuracy of the vehicle behavior is lowered due to the GPS reception status. It is to provide a highly reliable operation evaluation apparatus by evaluating the stability.

  The driving evaluation apparatus of the present invention estimates the behavior of the vehicle based on the current position of the vehicle to be evaluated, the GPS reception time, and the vehicle speed included in the GPS reception information, and receives the time interval between the estimated behavior value and the GPS reception time. The accuracy of the behavior estimation value is calculated based on the time, and the driving evaluation value is set from the calculated behavior estimation value and the accuracy of the behavior estimation value, and the evaluation value is displayed.

  According to the driving evaluation apparatus according to the present invention, the behavior estimation accuracy is calculated according to the GPS reception status. Therefore, even when the calculation accuracy of the vehicle behavior is lowered due to the GPS reception status, the driving evaluation device is operated by an appropriate method. By performing the evaluation, a highly reliable operation evaluation can be performed.

It is a block diagram which shows the structure of the driving | running evaluation apparatus concerning embodiment of this invention. It is a schematic diagram which shows an example of the specific apparatus structure of the driving | running evaluation apparatus of FIG. It is a flowchart which shows 1st Embodiment of the driving | running evaluation apparatus shown in FIG. It is a graph which shows an example of the relationship between GPS data update time and the precision of a lateral acceleration estimated value. It is a graph which shows an example of the relationship between a DOP value and the precision of a lateral acceleration estimated value. It is a graph which shows an example of the relationship between positional offset amount and the precision of a lateral acceleration estimated value. It is a graph which shows an example of the relationship between the precision of a lateral acceleration estimated value, and stability determination lateral acceleration. It is a graph which shows an example of the relationship between the precision of a lateral acceleration estimated value, and the predetermined excess time of stability determination lateral acceleration. It is a graph which shows an example of the relationship between the average value of the precision of a lateral acceleration estimated value, and the weight of a driving | running evaluation value. It is the schematic which shows an example of a driving | running evaluation value output. It is the schematic which shows the other example of a driving | running evaluation value output. It is a flowchart which shows operation | movement of the driving | running evaluation apparatus concerning the 2nd Embodiment of this invention. It is a table | surface which shows an example of the relationship between a behavior estimation precision step and the display content of a driving | running evaluation result. It is explanatory drawing explaining estimation of the vehicle behavior in a different position. It is explanatory drawing explaining estimation of the vehicle behavior in a certain position.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same parts are denoted by the same reference numerals.

(First embodiment)
With reference to FIG. 1, the structure of the driving | running evaluation apparatus concerning embodiment of this invention is demonstrated. The driving evaluation device is provided in the vehicle to be evaluated, and transmits and receives a GPS signal by transmitting a GPS signal of the vehicle position received from the global positioning system (GPS) to the driving evaluation unit 20. 10, a vehicle speed sensor 90 that outputs information on wheel speed or vehicle speed, and a driving evaluation unit 20 that performs driving evaluation from vehicle behavior and behavior estimation accuracy based on GPS reception information and vehicle speed included in the GPS signal, The operation input switch 30 that receives an operation from the user and the display 40 that displays the driving evaluation value to the driver are provided.

  The driving evaluation unit 20 includes a GPS signal input unit 50 that receives an input of a GPS signal transmitted by the GPS signal receiving / transmitting unit 10 at an arbitrary reception time, information included in the GPS signal received by the GPS signal input unit 50, and a vehicle speed sensor CPU 60 that calculates the driving stability based on the vehicle speed signal detected at 90 and the operation signal from the operation input switch 30; a memory 70 that stores data necessary for calculation processing in the CPU 60; and a driving evaluation calculated by the CPU 60. And an operation evaluation result output unit 80 for outputting the result to the display 40.

Signal transmission / reception between the GPS signal receiving / transmitting unit 10 and the GPS signal input unit 50 is performed via wireless communication such as Bluetooth, IrDA, and an Internet line, or via a recording medium such as a compact flash (registered trademark) or an SD memory card. For example, it can be arbitrarily selected according to the usage form of the apparatus. The driving evaluation result calculated by the CPU 60 can be output to another computer via wireless communication or a recording medium.

With reference to FIG. 2, an example of a specific configuration of the driving evaluation apparatus of FIG. 1 will be described. The vehicle is equipped with a GPS sensor 110 that receives GPS signals, a signal acquisition unit 120, and a transmitter 130. The signal acquisition unit 120 acquires a vehicle signal such as a GPS signal received by the GPS sensor 110 and a vehicle speed signal detected by the vehicle speed sensor 90 or an operation signal from the operation input switch 30. The signal acquired by the signal acquisition unit 120 is wirelessly transmitted to the driving evaluation server 140 by the transmitter 130. The driving evaluation server 140 calculates a driving evaluation value based on the received signal and referring to data stored in a built-in memory. The calculated driving evaluation value is transmitted to the computer 150 used by the user based on the request received from the computer 150 used by the user, and the user can view the driving evaluation result through the computer 150. In addition, the user (driver | operator) can browse the own driving | operation stability in a vehicle by using the display screen of the computer 150 as a vehicle-mounted display. In the present embodiment, the driving evaluation server 140 and the display of the computer 150 are assumed to be outside the vehicle, but these may be provided inside the vehicle.

  1 corresponds to the GPS sensor 110 and transmitter 130 provided in the vehicle of FIG. 2, and the CPU 60 of FIG. 1 corresponds to the signal acquisition unit 120. The driving evaluation unit 20 in FIG. 1 corresponds to the driving evaluation server 140 in FIG. The display 40 in FIG. 1 corresponds to the display of the computer 150 in FIG.

  Next, with reference to FIG. 3, operation | movement of the driving | running evaluation apparatus shown in FIG. 1 is demonstrated. FIG. 3 is a flowchart showing an example of the operation of the driving evaluation apparatus shown in FIG. 1. The processing operation of FIG. 3 is a GPS that is measured and inputted at regular intervals, for example, every second that is a GPS signal update cycle. It is an example of the processing operation performed by CPU60 with respect to a signal.

(A) First, in step S101, a GPS signal specified by GPS and related to the current position of the vehicle to be evaluated is received at a time (GPS receiving means). Specifically, the GPS signal receiving / transmitting unit 10 receives a GPS signal related to the current position of the vehicle to be evaluated, and transmits this signal to the GPS signal input unit 50.

Next, proceeding to step S102, the GPS signal input unit 50 obtains the current position of the vehicle to be evaluated, which is received at a time, and stores the current time in the memory 70 as GPS data with the reception time added to the GPS signal. Set (reception time setting means).

Next, proceeding to step S103, the vehicle speed sensor 90 corresponding to the reception time set in step S102.
The vehicle speed signal detected by (vehicle speed detection means) is input.

Next, the process proceeds to step S104, and the behavior of the vehicle is estimated from the GPS data obtained by adding the reception time to the GPS signal stored in step S102 and the vehicle speed signal detected by the vehicle speed sensor 90 (behavior estimation means). Examples of “behavior” of the vehicle include “lateral acceleration” applied in the left-right direction of the vehicle, “maximum deceleration” by braking, “vehicle speed”, etc. An example will be described.

Specifically, as shown in FIG. 14, the azimuth angle ψ (t) of the vehicle at time t is obtained from the positions (coordinates) of two points acquired from the GPS reception information represented by times t and t + 1. . Note that {LonP (t) (Longitude), LatP (t) (Latitude)} used in the following formula is the predicted position by GPS, and {Lon (t), Lat (t)} is the current position observed by GPS. is there.

Pm (t) = (lon (t), lat (t))
Pm (t-1) = (lon (t-1), lat (t-1))
ψ (t) = atan (Pm (t), Pm (t + 1)) (1)

Next, as shown in FIG. 15, the azimuth angle change Δψ (t) at time t is obtained from the difference between the azimuth angles at times t−1 and t.

Δψ (t) = ψ (t)-ψ (t-1) (2)

From the azimuth angle change amount Δψ (t) and the vehicle speed value V by the vehicle speed sensor 90 at times t−1 and t, the speed V with respect to the vehicle axis is expressed as shown in Equation 3, the vehicle traveling direction is Vx, and the vehicle traveling direction is The perpendicular direction is obtained as Vy, and the acceleration A is obtained from the time differentiation of the velocity V. The lateral component of the vehicle is assumed as the lateral acceleration estimated value Ay (t).

Vx (t) = V (t)-V (t-1) cos (Δψ (t)) (3)
Vy (t) = V (t-1) sin (Δψ (t))
Ay (t) = Vy (t) / Δt where Δt = 1 sec

  In step S105, the reception time is obtained from the lateral acceleration estimated value Ay (t) obtained by estimating the vehicle behavior and the difference between the reception time at the previous position and the reception time at the current position of the vehicle to be evaluated included in the GPS data. The accuracy vbp of the behavior estimation value set so that the behavior estimation accuracy becomes higher as the length of the reception time becomes shorter (behavior estimation accuracy calculation means).

  Specifically, in GPS data, the time before and after the current position of the vehicle is updated (GPS update time) is calculated, and the accuracy vbp of the lateral acceleration estimated value is calculated. When there is a time when the GPS data is not updated, the latitude and longitude being updated are obtained by interpolation using the longitude and latitude information before and after the update and the vehicle speed. As the time during which the GPS data is not updated becomes longer, the interpolation accuracy decreases. Therefore, the relationship between the GPS data update time and the lateral acceleration estimation accuracy is set as shown in FIG. 4, for example. Here, the estimated lateral acceleration accuracy vbp is set to be multiplied by the estimated lateral acceleration as a correction coefficient between 0 and 1.

As shown in FIG. 4, if the GPS minimum update time is 1 s, 1 is calculated as the accuracy of the lateral acceleration estimated value when the update time is 1 s. When the GPS data update time is 1 s or longer, the accuracy of the lateral acceleration estimated value decreases as the time during which the GPS data is not updated increases. When the GPS data update time exceeds a certain value, 0 is calculated as the accuracy of the lateral acceleration estimated value.

The calculation method of the accuracy vbp of the lateral acceleration estimated value is, for example, as shown in FIG. 4 in which a graph showing the relationship between the GPS data update time and the accuracy vbp of the lateral acceleration estimated value is stored in the memory 70 as data, and according to this data The accuracy vbp of the lateral acceleration estimated value may be calculated. Graphs shown in FIGS. 5 to 9 described later are also stored in the memory 70 as data in the same manner as in FIG.

  In step S105, the accuracy vbp of the lateral acceleration estimated value may be calculated by adding not only the update time of the current position of the vehicle to be evaluated but also a GPS accuracy reduction rate (DOP: Dillution Of Precision). Specifically, the accuracy vbp of the lateral acceleration estimated value is calculated based on the graph shown in FIG. In the graph shown in FIG. 5, the GPS accuracy is lowered as the DOP value increases, and accordingly, the accuracy vbp of the lateral acceleration estimated value is also lowered.

In step S105, not only the update time of the current position of the vehicle to be evaluated, but also the predicted position {LonP (t) (longitude), LatP (t) (latitude)} by GPS and the current position {Lon (t), Lat (t)} distance (position displacement amount Le) is further added, and the accuracy vb of the lateral acceleration estimated value
p may be calculated. Specifically, the accuracy vbp of the lateral acceleration estimated value is calculated based on the graph shown in FIG. Alternatively, the accuracy vbp of the lateral acceleration estimated value may be calculated as the average accuracy based on the graphs shown in FIGS. 4, 5, and 6. In the graph shown in FIG. 6, the accuracy vbp of the lateral acceleration estimated value is set to decrease as the positional deviation amount Le increases. Note that the predicted position {LonP (t), LatP (t)} is obtained from, for example, the expressions (4) and (5), and the positional deviation amount Le is obtained from the expression (6).

LonP (t) = Lon (t-1) + (Lon (t-1) -Lon (t-2))
+ 1/2 × {(Lon (t-1) -Lon (t-2))-(Lon (t-2) -Lon (t-3))} (4)

LatP (t) = Lat (t-1) + (Lat (t-1) -Lat (t-2))
+ 1/2 × {(Lat (t-1) -Lat (t-2))-(Lat (t-2) -Lat (t-3))} (5)

Le = sqrt ((LonP (t) -Lon (t)) ² + (LatP (t) -Lat (t)) ² ) (6)

  (C) In step S106, the estimated lateral acceleration estimated value Ay (t) of the vehicle to be evaluated exceeds the reference acceleration of the maximum lateral acceleration during turning according to the accuracy vbp of the estimated lateral acceleration value obtained in step S105. By determining whether or not, the stability regarding the driving for determining whether or not the estimated lateral acceleration value Ay (t) can be adopted is set. (Stability setting means). Specifically, the maximum lateral acceleration is selected from the lateral acceleration estimated values Ay (t), and the behavioral stability reference is obtained from the accuracy vbp of the lateral acceleration estimated value calculated in S105 according to the graph shown in FIG. The stability determination lateral acceleration value xgo is set as an estimated stability determination value. In the graph shown in FIG. 7, the accuracy of estimation decreases as the accuracy vbp of the estimated lateral acceleration value decreases, and the stability determination lateral acceleration value xgo increases. The stability determination lateral acceleration value xgo has a characteristic that becomes smaller as the accuracy vbp of the lateral acceleration estimated value increases, and the lateral acceleration estimated value above the characteristic line of the stability determination setting value is evaluated. Is set as an area to be selected as a stable behavior, and conversely, the lower side is set as an area that is not a stable behavior and is not selected as an evaluation. Although the stability determination lateral acceleration value xgo in the present embodiment is set to 0.8, the present invention is not limited to this and may be set as appropriate for each vehicle.

Further, when it is determined whether or not the estimated maximum lateral acceleration exceeds the stability determination lateral acceleration value xgo, as shown in FIG. 8, the length of time that the stability determination lateral acceleration value xgo is exceeded. It is determined whether to select the estimated value of the lateral acceleration to be evaluated based on whether the acceleration value continues as described above. In the graph shown in FIG. 8, for example, the excess predetermined time ta of the stability determination lateral acceleration value xgo is set longer as the accuracy vbp of the estimated lateral acceleration value becomes smaller. In this embodiment, the maximum value of the excess predetermined time ta of the stability determination lateral acceleration value xgo is set to 200 m.
However, the present invention is not limited to this, and can be appropriately set according to the characteristics of the vehicle.

    In step S107, based on the accuracy vbp of the lateral acceleration estimated value, for example, when the maximum value xg_max of the lateral acceleration estimated value in one turning scene is used as a behavior index, all the travel units to be evaluated such as trips and predetermined days are evaluated. In the turning scene, the ratio of the turning scene where the maximum lateral acceleration estimated value xg_max is equal to or greater than the lateral acceleration stability determination lateral acceleration value xgo set in step S106 is calculated. Specifically, the ratio of the number nrs of the number of turning scenes that are equal to or less than the threshold value xgo out of the number Nr of all turning scenes of the travel unit to be evaluated is calculated as the driving evaluation value Est (Score_r) according to the equation (7). Calculate as (Evaluation value setting means).

Est (Score_r) = (nrs / Nr) × 100 (7)

    In addition, the above-mentioned turning scene, for example, obtains an azimuth change from a plurality of GPS latitude / longitude point sequences, and extracts a scene in which an azimuth change of a predetermined value or more occurs. Then, as the lateral acceleration xg, the change amount per unit time of the azimuth change is obtained, and the lateral component is extracted.

(D) In step S108, the driving evaluation value Est (Score_r) set in step S107 is output to the display 40, and the driving evaluation value is displayed on the display 40 as shown in FIG. 10 (display means), for example.

  This ends the processing procedure shown in FIG. In this manner, the driving evaluation apparatus of FIG. 1 estimates the behavior of the vehicle based on the GPS reception information, obtains the estimation accuracy of the behavior, and evaluates the driving of the vehicle based on the estimation accuracy of the behavior. The driver can be fed back to the driver by displaying the evaluation result.

  In addition, although the lateral acceleration maximum value that is the steering wheel operation is illustrated as the behavior index that is the evaluation target, the present invention is not limited to this, and for example, the deceleration maximum value that is the brake operation and the vehicle speed are similarly evaluated as the driving stability. be able to.

For example, regarding the vehicle speed, the ratio of the time Tr_vo that travels below the vehicle speed reference value Vo in the travel time Tr may be calculated as a set value (Score_v) according to the equation (8).

      Score_v = (Tr_vo / Tr) x 100 (8)

Alternatively, with respect to the brake operation, for example, a signal for determining on / off of the brake is input as a vehicle signal, and a case where the brake is on for a predetermined time or more is counted as a deceleration scene. Of the number Nb of all deceleration scenes, the ratio of the number nbs of deceleration scenes where the maximum deceleration value is less than or equal to the threshold value MAX_XGo is calculated as a set value (Score_b) according to equation (9).

      Score_b = (nbs / Nb) × 100 (9)

A plurality of evaluation objects (steering wheel operation, vehicle speed, brake operation) can be statistically evaluated based on the plurality of behavior indexes (lateral acceleration maximum value, vehicle speed, deceleration maximum value). Specifically, using the above set values (Score_r, Score_v, Score_b), (10)
The total set value Score_Total may be calculated according to the equation and fed back to the driver.

      Score_Total = (Score_r + Score_v + Score_b) / 3 (10)

  As another example of calculating the driving evaluation value in step S107, as shown in FIG. 9, the weight w of the driving evaluation value may be set as a ratio according to the average value of the accuracy vbp of the estimated lateral acceleration value. Good. In the graph shown in FIG. 9, the weight w of the driving evaluation value may be set to increase as the accuracy vbp of the lateral acceleration estimated value increases (increases).

When the weight w of the driving evaluation value is used, in step S106, the stability regarding driving is set by multiplying the estimated lateral acceleration value by the weight w for one turning scene (FIG. 9), as follows. The driving evaluation value Est (Score_r) is calculated. Each weight of m turning scenes {1,..., i,. The raw point Pri of each turning scene is set as follows. That is, when the lateral acceleration maximum value xg_max is lower than the threshold value xgo, the prime point Pri = wi is set, and when the lateral acceleration maximum value xg_max exceeds the threshold value xgo, the prime point Pri = 0 is set. Then, an operation evaluation value Est (Score_r) is calculated according to the equation (7).

Furthermore, as an output example of the driving evaluation value output in step S108, in addition to the calculated set value (Score_r), for example, the location and date and time when the lateral acceleration maximum value xg_max exceeds the threshold value xgo are received by GPS. You may detect from information and display the generation | occurrence | production location P on an electronic map. For example, as shown in FIG. 11, setting values (Score_r, Score_v, Score_b) in a plurality of evaluation objects (steering wheel operation, vehicle speed, braking operation), statistical setting values (total Score_Total), and detailed information The location and date / time at which the “accelerated steering operation” in which the maximum value xg_max of the estimated acceleration value exceeds the threshold value xgo may be displayed simultaneously. Thereby, a specific evaluation result can be fed back to the driver. Details of this will be described in the second embodiment.

  As described above, in the first embodiment of the present invention, the following operational effects can be obtained.

The time when the current position information of the vehicle included in the GPS reception information is updated is sequentially stored, and the update time of the current position of the vehicle is obtained based on this time, and the lateral acceleration obtained from the update time and the vehicle speed is calculated. The accuracy of the lateral acceleration estimated value is calculated based on the estimated value, the driving evaluation value is set based on the estimated behavior of the vehicle and the estimated accuracy of the behavior, and this driving evaluation is displayed. Thereby, even when the accuracy of the estimated lateral acceleration value of the vehicle is lowered depending on the GPS reception status, the driving evaluation can be performed by an appropriate method.

  The accuracy of the lateral acceleration estimated value is calculated based on the GPS accuracy reduction rate (DOP: Dillution Of Precision). As a result, even when the DOP value increases and the accuracy of the estimated lateral acceleration value of the vehicle decreases, driving evaluation can be performed by an appropriate method.

  Based on the distance between the predicted position by GPS and the current position (observation position) observed by GPS, the accuracy of the estimated lateral acceleration is calculated. As a result, the positional deviation amount Le for the predicted position and the observation position can be calculated. The larger the positional deviation amount Le, it is judged that the accuracy of the estimated lateral acceleration of the vehicle is worse, and the reliability of the data is lowered and the driving evaluation value As a result, the evaluation accuracy is improved.

By comparing the lateral acceleration estimated value of the vehicle with the stability determination lateral acceleration value xgo, a highly stable lateral acceleration estimated value is extracted, and driving evaluation is performed based on the lateral acceleration estimated value. Thereby, driving | running evaluation can be performed with a behavior with high stability, and evaluation accuracy improves.

It is determined whether or not the state where the estimated lateral acceleration value of the vehicle is equal to or greater than the stability determination lateral acceleration value xgo continues for the excess time ta or more, and whether to accept the estimated lateral acceleration value is determined. As a result, the accuracy of the estimated value increases, thereby improving the evaluation accuracy.

Furthermore, in the present embodiment, the stability determination lateral acceleration value xgo and the excess time ta are variably set according to the accuracy of the lateral acceleration estimated value, so that the estimation accuracy can be further increased and the evaluation accuracy is improved.

(Second Embodiment)
In the second embodiment, a case will be described in which the display detail level of the driving evaluation value is changed according to the calculation accuracy of the behavior index. The display detail level of the driving evaluation value indicates the detail level of the content of the evaluation result output to the display 40. For example, the set value of each evaluation target (handle operation, vehicle speed, brake operation) shown in FIG. (Score_r, Score_v, Score_b), statistical setting value (Score_Total), location and date / time of “steep handle operation”, the type of items to be displayed on the display 40 according to the calculation accuracy of the behavior index Indicates restriction.

  FIG. 12 is a flowchart illustrating an example of the operation of the driving evaluation apparatus according to the second embodiment. The hardware configuration of the driving evaluation apparatus according to the second embodiment is the same as the configuration shown in FIGS. 1 and 2 except for the steps S201 and S202, and the same parts are illustrated and described. Omitted.

  In step S201, the display detail level of the set value is changed according to the calculation accuracy of the lateral acceleration index. In step S202, the setting value is displayed on the display 40.

Specifically, as shown in the table of FIG. 13, it is a stage display unit that divides the accuracy of the lateral acceleration estimated value into three stages (high, medium, and low), specifically, when it is at a high level. FIG. 11 shows an altitude display section that displays the location and date and time of the “steep handle operation” shown in FIG. 11 and, in the middle level, displays only the location that had the “steep handle operation” shown in FIG. In the case of the low-level display portion and the low-level display portion, it is divided into a low-level display portion that does not display the location and date / time of “steep handle operation” shown in FIG. 11 (display means). This display content is changed according to the accuracy of the lateral acceleration estimated value. Of course, regardless of the calculation accuracy of the behavior index, the evaluation values (Score_r, Score_v, Score_b) and the overall evaluation values (Score_Total) of each driving operation (steering operation, vehicle speed, braking operation) shown in FIG. Display on the display 40.

  Thus, the display detail level of the set value is changed according to the accuracy of the behavior estimated value. Specifically, the display content is changed so as to lower the display detail level of the setting value as the accuracy of the behavior estimation value is lower. Thereby, driving evaluation can be displayed by an appropriate method.

(Other embodiments)
As described above, the present invention has been described in terms of two embodiments, but it should not be understood that the discussion and drawings that form part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. That is, it should be understood that the present invention includes various embodiments and the like not described herein.

  In the first embodiment, when the reference value of the behavior index used when evaluating the driving stability is corrected according to the accuracy of the behavior estimated value, the behavior estimated value of the second embodiment is corrected. The case where the display detail level of the set value is changed according to the accuracy is shown separately. However, these corrections and changes may be performed simultaneously. That is, an embodiment in which the first embodiment and the second embodiment are combined is one of the other embodiments of the present invention.

10 GPS signal receiving and transmitting unit (GPS receiving means)
20 driving evaluation unit 30 operation input switch 40 display 50 GPS signal input unit (GPS receiving means)
60 CPU (behavior estimation means, behavior estimation accuracy calculation means, evaluation value setting means, stability setting means)
70 Memory 80 Driving Evaluation Result Output Unit 90 Vehicle Speed Sensor 110 GPS Sensor 120 Signal Acquisition Unit 130 Transmitter 140 Driving Stability Evaluation Server 150 Computer

Claims (4)

GPS receiving means for receiving, at an arbitrary reception time, information on the current position of the evaluation target vehicle specified by GPS;
Reception time setting means for setting the GPS reception means while storing the reception time received at a time;
Vehicle speed detection means for detecting the vehicle speed of the vehicle to be evaluated corresponding to the reception time set by the reception time setting means;
Evaluation target vehicle based on the current position of the evaluation target vehicle specified by GPS, the reception time set by the reception time setting means, and the vehicle speed detected by the vehicle speed detection means, received by the GPS reception means Behavior estimation means for estimating the behavior of
Behavior estimation that calculates the accuracy of the behavior estimation value based on the behavior estimation value of the vehicle to be evaluated estimated by the behavior estimation means and the reception time that is the time interval of the reception time stored in the reception time setting means Accuracy calculation means;
Evaluation value setting means for setting a driving evaluation value of the vehicle to be evaluated based on the behavior estimated value estimated by the behavior estimating means and the accuracy of the behavior estimated value calculated by the behavior estimation accuracy calculating means;
A driving evaluation apparatus comprising: display means for displaying the driving evaluation value set by the evaluation value setting means. The behavior estimation unit compares the behavior estimation value of the vehicle to be evaluated estimated by the behavior estimation unit with a stability determination estimation value serving as a reference for the behavior stability set in advance. Having a stability setting means for setting the stability;
The driving evaluation apparatus according to claim 1, wherein the behavior estimation unit uses a behavior estimation value determined as a stable behavior based on a comparison result of the behavior estimation value by the stability setting unit. The stability setting unit is configured to compare the estimated behavior value of the evaluation target vehicle estimated by the behavior estimation unit with a stability determination estimated value serving as a reference for preset behavior stability. 3. The driving evaluation apparatus according to claim 2, wherein the behavior estimation value is set as a behavior estimation value if the behavior estimation value continues beyond a preset excess time. The display means includes a stage display unit divided into a plurality of stages as the display detail level of the driving evaluation value of the evaluation target vehicle, and changes the display content of the stage display unit according to the accuracy of the estimated lateral acceleration value. The driving evaluation device according to claim 1, wherein the driving evaluation device is displayed.

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