JP2010205082A - Acceleration calculation device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acceleration calculation device or the like which is capable of performing appropriate evaluation on the basis of an actually measured value of acceleration. <P>SOLUTION: The acceleration calculation device includes: a long-term acceleration calculation part which calculates a long-term acceleration being an average value of measured accelerations measured in a predetermined time range; a difference acceleration calculation part which calculates difference accelerations resulting from subtracting the measured accelerations from the long-term acceleration; a variation width calculation part which calculates a positive-direction variation width being a variation width of difference accelerations in a period when the sign of difference accelerations is positive, and calculates a negative-direction variation width being a variation width of difference accelerations in a period when the sign of difference accelerations is negative; a weight calculation part which calculates weights for the measured accelerations in such a manner that the larger difference between the positive-direction variation width and the negative-direction variation width is, the more the weights for the measured accelerations are heavier than those for the long-term acceleration; and an acceleration calculation part which calculates weighted accelerations resulting from weighting the measured accelerations and the long-term acceleration by the weights, as corrected accelerations. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an acceleration calculation device and an acceleration calculation method.

  There is known an apparatus that calculates a driving risk by using a change in acceleration with time (see, for example, Patent Document 1).

JP 2007-164525 A

  In a system that evaluates driving risk using time variation of acceleration obtained by an acceleration sensor, the risk level may be excessively evaluated due to the influence of vehicle body recoil. Further, even if a large acceleration value is obtained as an absolute value, it may not be determined as dangerous driving if the time change is small.

  On the other hand, in a system that calculates the degree of risk using the magnitude of the measured acceleration instead of the time change, the risk level may not be properly evaluated due to the influence of the DC component of the acceleration measurement value. is there. Such a DC component may occur, for example, when the initial setting of the acceleration sensor is not accurately performed or when the vehicle is traveling on a slope. In addition, when traveling on an uneven road surface such as a step, an acceleration that is greatly affected by the unevenness may be measured.

  In this way, acceleration that deviates from the acceleration that is actually desired to be evaluated may be measured, and accordingly, the driving risk level may not be properly evaluated. That is, there is a problem that proper evaluation cannot be performed from the measured value of acceleration.

  In order to solve the above-described problem, in the first aspect of the present invention, an acceleration calculation apparatus that calculates a corrected acceleration obtained by correcting a measured acceleration, which is a measured acceleration of a vehicle body, is greater than a predetermined value. A time history acquisition unit that acquires time history data including measurement acceleration measured within a predetermined time range from the time when the measurement acceleration is measured, and an average of measurement acceleration in a period longer than a predetermined time length Long-term acceleration calculation unit for calculating a long-term acceleration, a differential acceleration calculation unit for calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration, and a fluctuation range of the differential acceleration within a period in which the sign of the differential acceleration is positive And a fluctuation range calculation unit for calculating a negative direction fluctuation range that is a fluctuation range of the differential acceleration within a period in which the sign of the differential acceleration is negative, and a positive direction The greater the difference between the dynamic range and the negative direction fluctuation range, the greater the weight for the measured acceleration than the long-term acceleration, and the measured acceleration and the long-term acceleration are weighted with the weight calculated by the weight calculating unit. A weighted acceleration calculating unit that calculates the weighted acceleration as a corrected acceleration;

  The fluctuation range calculation unit further calculates the fluctuation range of the measured acceleration within the time range and the fluctuation range of the differential acceleration within the time range, and the weight calculation unit calculates the difference between the positive direction fluctuation range and the negative direction fluctuation range. The larger the ratio of the fluctuation width of the measured acceleration to the fluctuation width of the differential acceleration, the greater the weight for the measured acceleration may be calculated than the long-term acceleration.

  The time history acquisition unit acquires time history data further including the speed of the vehicle body measured within the time range from the time when the measured acceleration greater than a predetermined value is measured, and the acceleration calculation device calculates the time history data from the time history data. In the time range, a period specifying unit that specifies a period in which the amount of temporal change in speed is smaller than a predetermined value, and a measurement within a period specified by the period specifying unit from the measured acceleration included in the time history data A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measured acceleration, and the long-term acceleration calculation unit uses an average value of the subtraction acceleration as a long-term acceleration for a period longer than a predetermined time length. The differential acceleration calculation unit calculates the differential acceleration by subtracting the long-term acceleration from the subtraction acceleration, and the fluctuation range calculation unit calculates the subtraction acceleration within the time range. The fluctuation width is calculated, and the positive fluctuation width, the negative fluctuation width, and the fluctuation width of the differential acceleration within the time range are calculated from the differential acceleration obtained from the subtraction acceleration. The difference between the obtained positive direction fluctuation range and the negative direction fluctuation range obtained from the subtraction acceleration is large, and the larger the ratio of the subtraction acceleration fluctuation range to the differential acceleration fluctuation range obtained from the subtraction acceleration, the longer the long-term acceleration. The weight for the subtraction acceleration may be calculated to be larger, and the weighted acceleration calculation unit may calculate the weighted acceleration obtained by weighting the subtraction acceleration and the long-term acceleration with the weight calculated by the weight calculation unit as the corrected acceleration.

  The time history acquisition unit acquires time history data further including the speed of the vehicle body measured within the time range from the time when the measured acceleration greater than a predetermined value is measured, and the acceleration calculation device calculates the time history data from the time history data. In the time range, a period specifying unit that specifies a period in which the amount of temporal change in speed is smaller than a predetermined value, and a measurement within a period specified by the period specifying unit from the measured acceleration included in the time history data A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measured acceleration, and the long-term acceleration calculation unit uses an average value of the subtraction acceleration as a long-term acceleration for a period longer than a predetermined time length. The difference acceleration calculation unit calculates the difference acceleration by subtracting the long-term acceleration from the subtraction acceleration, and the fluctuation range calculation unit calculates the difference addition obtained from the subtraction acceleration. From the degree, the positive direction fluctuation range and the negative direction fluctuation range are calculated, and the weight calculation unit increases the difference between the positive direction fluctuation range obtained from the subtraction acceleration and the negative direction fluctuation range obtained from the subtraction acceleration. The weight for the subtraction acceleration is calculated to be larger than the acceleration, and the weighted acceleration calculation unit may calculate a weighted acceleration in which the subtraction acceleration and the long-term acceleration are weighted by the weight calculated by the weight calculation unit as the corrected acceleration. .

  According to a second aspect of the present invention, there is provided an acceleration calculation method for calculating a corrected acceleration obtained by correcting a measured acceleration which is a measured acceleration of a vehicle body, from a time when a measured acceleration greater than a predetermined value is measured. A time history acquisition stage that acquires time history data including measured acceleration measured within a predetermined time range, and a long-term acceleration that is an average value of measured acceleration in a period longer than a predetermined time length is calculated. A long-term acceleration calculation stage, a differential acceleration calculation stage for calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration, a positive-direction fluctuation width that is a fluctuation width of the differential acceleration within a period in which the sign of the differential acceleration is positive, and , A fluctuation range calculation stage for calculating a negative direction fluctuation range that is a fluctuation range of the differential acceleration within a period in which the sign of the differential acceleration is negative, and a positive direction fluctuation range and a negative direction fluctuation The greater the difference between, the weight calculation stage that calculates a greater weight for the measured acceleration than the long-term acceleration, and the weighted acceleration in which the measured acceleration and the long-term acceleration are weighted with the weight calculated in the weight calculation stage are corrected. A weighted acceleration calculation stage for calculating acceleration.

  According to a third aspect of the present invention, there is provided an acceleration calculation device for calculating a corrected acceleration obtained by correcting a measured acceleration which is a measured vehicle body acceleration, from a time when a measured acceleration greater than a predetermined value is measured. A time history acquisition unit that acquires time history data including measured acceleration measured within a predetermined time range, and calculates a long-term acceleration that is an average value of measured acceleration over a period longer than a predetermined time length A long-term acceleration calculating unit, a differential acceleration calculating unit that calculates a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration, a fluctuation range of the measured acceleration within the time range, and a fluctuation range of the differential acceleration within the time range The larger the ratio of the fluctuation range of the measured acceleration to the fluctuation range of the differential acceleration and the fluctuation range of the measured acceleration, the more weight the measured acceleration than the long-term acceleration. Ri comprises a weight calculation unit that calculates increased, the weighting acceleration measurement acceleration and long-term acceleration is weighted by weights weight calculation unit has calculated, and a weighting acceleration calculating unit for calculating a correction acceleration.

  The time history acquisition unit acquires time history data further including the speed of the vehicle body measured within the time range from the time when the measured acceleration greater than a predetermined value is measured, and the acceleration calculation device calculates the time history data from the time history data. In the time range, a period specifying unit that specifies a period in which the amount of temporal change in speed is smaller than a predetermined value, and a measurement within a period specified by the period specifying unit from the measured acceleration included in the time history data A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measured acceleration, and the long-term acceleration calculation unit uses an average value of the subtraction acceleration as a long-term acceleration for a period longer than a predetermined time length. The differential acceleration calculation unit calculates the differential acceleration by subtracting the long-term acceleration from the subtraction acceleration, and the fluctuation range calculation unit calculates the subtraction acceleration within the time range. While calculating the fluctuation range, the differential acceleration fluctuation range within the time range is calculated from the differential acceleration obtained from the subtraction acceleration, and the weight calculation unit calculates the subtraction acceleration relative to the differential acceleration fluctuation width obtained from the subtraction acceleration. The larger the fluctuation ratio, the greater the weight for the subtraction acceleration than the long-term acceleration, and the weighted acceleration calculation unit weights the subtraction acceleration and the long-term acceleration with the weight calculated by the weight calculation unit. May be calculated as a corrected acceleration.

  According to a fourth aspect of the present invention, there is provided an acceleration calculation method for calculating a corrected acceleration obtained by correcting a measured acceleration that is a measured vehicle body acceleration, from a time when a measured acceleration greater than a predetermined value is measured. A time history acquisition stage that acquires time history data including measured acceleration measured within a predetermined time range, and a long-term acceleration that is an average value of measured acceleration in a period longer than a predetermined time length is calculated. A long-term acceleration calculation stage, a differential acceleration calculation stage for calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration, a fluctuation width of the measured acceleration within the time range, and a fluctuation width of the differential acceleration within the time range The larger the ratio of the fluctuation range of the measurement acceleration to the fluctuation range calculation stage and the fluctuation range of the differential acceleration, the greater the long-term acceleration is to the measurement acceleration Comprising a weight calculation step of larger calculates a weight, the weighting acceleration measurement acceleration and prolonged acceleration calculated weights are weighted in the weight calculation step, and a weighted acceleration calculating step of calculating a corrected acceleration.

  According to a fifth aspect of the present invention, there is provided an acceleration calculation device for calculating a corrected acceleration obtained by correcting a measured acceleration which is a measured vehicle body acceleration, from a time when a measured acceleration greater than a predetermined value is measured. A time history acquisition unit that acquires time history data including the speed and measurement acceleration of the vehicle body measured within a predetermined time range, and a temporal change amount of the speed within the time range is determined in advance from the time history data. A period specifying unit that specifies a period smaller than a predetermined value and a subtraction acceleration obtained by subtracting the measured acceleration within the period specified by the period specifying unit from the measured acceleration included in the time history data is corrected acceleration. And a subtraction acceleration calculation unit.

  In the first, third, and fifth aspects, the period specifying unit is configured such that the temporal change amount of the speed is smaller than a predetermined value and the temporal change amount of the measurement acceleration is predetermined within the time range. A period less than the given value may be specified.

  In the first, third, and fifth aspects, the apparatus further includes a long-term measurement acceleration calculating unit that calculates long-term measurement acceleration that is an average value of measurement acceleration in a period longer than a predetermined time length from the time history data. Within the time range, the period specifying unit is configured such that the temporal change in speed is smaller than a predetermined value, the temporal change in measurement acceleration is smaller than a predetermined value, and the long-term measurement acceleration time A period in which a typical change amount is smaller than a predetermined value may be specified.

  In the first, third, and fifth aspects, the subtraction acceleration calculating unit subtracts the corrected acceleration by subtracting the average value of the measured acceleration within the period specified by the period specifying unit from the measured acceleration included in the time history data. It may be calculated.

  According to a sixth aspect of the present invention, there is provided an acceleration calculation method for calculating a corrected acceleration obtained by correcting a measured acceleration that is a measured vehicle body acceleration, from a time when a measured acceleration greater than a predetermined value is measured. A time history acquisition stage for acquiring time history data including the speed and measured acceleration of the vehicle body measured within a predetermined time range, and a temporal change amount of the speed within the time range is determined in advance from the time history data. A period specifying stage that specifies a period smaller than a predetermined value and a subtracted acceleration obtained by subtracting the measured acceleration within the period specified in the period specifying stage from the measured acceleration included in the time history data is corrected acceleration. Subtracted acceleration calculation stage.

  It should be noted that the above summary of the invention does not enumerate all the necessary features of the present invention. In addition, a sub-combination of these feature groups can also be an invention.

1 is a diagram illustrating an example of the overall configuration of an operation analysis system 100. FIG. It is a figure which shows an example of the processing flow in the drive recorder. It is a figure which shows an example of the block configuration of the driving | running analysis apparatus. It is a figure which shows an example of the processing flow which the driving | running analysis apparatus 110 calculates a subtraction acceleration. It is a figure which shows an example of the processing flow which the driving | running analysis apparatus 110 correct | amends subtraction acceleration. It is a figure which shows typically an example of the subtraction acceleration obtained by the offset correction process. It is a figure which shows typically an example of the waveform of a subtraction acceleration. It is a figure which shows typically another example of the waveform of a subtraction acceleration. It is a figure which shows typically another example of the waveform of a subtraction acceleration.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 shows an example of the overall configuration of the driving analysis system 100. The driving analysis system 100 calculates the risk of driving behavior by the driver of the vehicle 160 by analyzing the acceleration data measured by the vehicle 160.

  The driving analysis system 100 includes a driving analysis device 110, an analysis result DB 120, a user terminal 150, and a drive recorder 170 provided in the vehicle 160. In addition to the drive recorder 170, the vehicle 160 is provided with a speed sensor 182, a brake sensor 184, and a winker sensor 186.

  The speed sensor 182 generates a speed pulse indicating the vehicle speed of the vehicle 160. The speed sensor 182 may generate a speed pulse corresponding to the amount of rotation of the drive shaft, for example. The brake sensor 184 generates a brake signal corresponding to the brake amount, for example, by detecting the depression amount of the brake pedal. The winker sensor 186 generates a winker signal including winker information such as the presence / absence of a winker instruction and the direction of the winker instruction by detecting an output instruction to the winker device, for example. The drive recorder 170 receives the speed pulse from the speed sensor 182, the brake signal from the brake sensor 184, and the winker signal from the winker sensor 186.

  The drive recorder 170 includes an acceleration sensor 172, a camera 174, and a CPU 176. It is assumed that drive recorder 170 is fixed to vehicle 160.

  The acceleration sensor 172 measures the acceleration of the vehicle 160 and generates an acceleration signal. The acceleration sensor 172 may generate, as an acceleration signal, a signal corresponding to, for example, a position change amount or strain amount caused by acceleration. Examples of the acceleration detection method by the acceleration sensor 172 include a semiconductor type, an optical type, and a mechanical type.

  The acceleration sensor 172 is provided to detect at least acceleration in the straight traveling direction (traveling direction) of the vehicle 160. The acceleration sensor 172 may be a biaxial acceleration sensor, and may further detect an acceleration in a direction perpendicular to the straight traveling direction in the moving surface of the vehicle 160. The acceleration sensor 172 may be a triaxial acceleration sensor, and may further detect acceleration in a direction perpendicular to the moving surface of the vehicle 160.

  The camera 174 is provided in the vehicle 160 and generates a captured image signal. The camera 174 may take an image of the surroundings of the vehicle 160, particularly the space in the vehicle 160 at least in the straight direction. The camera 174 may take an image of the inside of the vehicle 160, particularly the driver of the vehicle 160.

  The drive recorder 170 is provided with a memory card slot into which a memory card 178 can be inserted. The drive recorder 170 records various measurement data on the memory card 178 inserted in the memory card slot by the processing of the CPU 176. Specifically, the drive recorder 170 includes an acceleration signal generated by the acceleration sensor 172, an imaging signal captured by the camera 174, a speed pulse from the speed sensor 182, a brake signal from the brake sensor 184, and a winker signal from the winker sensor 186. , And the processed data is recorded in the memory card 178.

  More specifically, the drive recorder 170 monitors the acceleration of the vehicle 160 indicated by the acceleration signal, and each time a rapid change in acceleration is detected, the acceleration and speed obtained within a predetermined time range before and after the acceleration are detected. The time history data including the imaging signal, the brake information, and the winker information is recorded in the memory card 178.

  When the operation of the vehicle 160 ends, the time history data stored in the memory card 178 is read by the user terminal 150. The user of the driving analysis device 110 transmits the time history data stored in the memory card 178 to the driving analysis device 110 using the user terminal 150. At this time, the user terminal 150 may transmit the time history data to the driving analysis device 110 via the network 140 such as the Internet. Note that the drive recorder 170 may transmit the time history data to the user terminal 150 or the driving analysis device 110 via the wireless communication or the like without using the memory card 178.

  The driving analysis device 110 is provided in a data center different from the user terminal 150 as an example. The driving analysis device 110 analyzes the driving behavior using the time history data transmitted from the user terminal 150 and records the analyzed result in the analysis result DB 120. The driving analysis device 110 analyzes driving behavior using at least measured acceleration (for example, absolute value of acceleration). At this time, the driving | running analysis apparatus 110 analyzes a driving | running behavior using the acceleration measured in the predetermined time range contained in time history data. As will be described later, the driving analysis device 110 corrects the influence of the inclination of the vehicle 160, the road surface step, and the like on the acceleration data, and analyzes the driving behavior based on the corrected acceleration.

  Examples of analysis results include types of dangerous driving such as sudden acceleration (rapid start) and sudden stopping, and risk levels for each type. The user terminal 150 acquires the analysis result from the analysis result DB 120 through the network 140 or the like, and displays the acquired analysis result on the screen. Thereby, the user can search and confirm information related to dangerous driving.

  According to the driving analysis system 100, the level of dangerous driving can be provided to the customer. The driving analysis system 100 can be applied to a management system that manages drivers such as buses and trucks. In this case, the analysis result can be used for evaluating the driver. The driving analysis system 100 can also be applied to a system that analyzes the driving behavior of a training vehicle at a driving school. In this case, for example, the analysis result can be used for student guidance or the like. The vehicle 160 is not limited to an automobile, and may be a vehicle that travels on land, such as a motorcycle or a train.

  Note that the recording medium 190 stores programs for the operation analysis device 110 and the analysis result DB 120. The program stored in the recording medium 190 is provided to an electronic information processing apparatus such as a computer that functions as the driving analysis apparatus 110 and the analysis result DB 120 according to the present embodiment. The CPU included in the computer operates according to the contents of the program and controls each unit of the computer. The program executed by the CPU causes the computer to function as the driving analysis device 110 and the analysis result DB 120 described with reference to this figure and subsequent figures.

  As the recording medium 190, in addition to a CD-ROM, an optical recording medium such as a DVD or PD, a magneto-optical recording medium such as an MO or MD, a magnetic recording medium such as a tape medium or a hard disk device, a semiconductor memory, a magnetic memory, etc. It can be illustrated. In addition, a storage device such as a hard disk or a RAM provided in a server system connected to a dedicated communication network or the Internet can function as the recording medium 190.

  FIG. 2 shows an example of a processing flow in the drive recorder 170. In S202, the drive recorder 170 determines whether or not to end the measurement data record including acceleration, speed, brake information, blinker information, and the like. For example, when it is set that the operation of the vehicle 160 is ended by the operation of the driver, it is determined that the record of the travel data should be ended. If it is determined that the measurement data record should be terminated, the process is terminated (END).

  While it is determined that the measurement data record should not be terminated, the drive recorder 170 sequentially stores the sampled measurement data in a volatile memory such as a RAM, and a predetermined time interval has elapsed. In this case, it is assumed that the data is updated with newly sampled travel data.

  In S204, the drive recorder 170 determines whether or not the measured acceleration has exceeded the threshold value T1. Here, the measured acceleration is assumed to indicate the acceleration of the vehicle 160 indicated by the acceleration signal from the acceleration sensor 172. The threshold T1 is a threshold used for the drive recorder 170 to determine whether or not to record time history data on the memory card 178. If it is determined in S204 that the measured acceleration does not exceed the threshold value T1, the drive recorder 170 returns the process to S202.

  If it is determined in S204 that the measured acceleration has exceeded the threshold value T1, in S206, the drive recorder 170 stores the measured data sampled after a predetermined period of time in a non-volatile memory so as not to be updated. Hold already stored measurement data. For example, the drive recorder 170 holds measurement data for a period of 12 seconds before the current time. In the description of this figure, the “current time” indicates the time when it is determined that the measured acceleration exceeds the threshold value T1.

  In S208, the drive recorder 170 stores the measurement data obtained up to a predetermined period after the present in the volatile memory. For example, the drive recorder 170 stores measurement data sampled in a period from the current time to 6 seconds later in the volatile memory.

  In S210, the drive recorder 170 writes the measurement data recorded in the volatile memory to the memory card 178. For example, the drive recorder 170 writes measurement data from 6 seconds before the current time to 12 seconds after the current time in the memory card 178. Subsequently, the drive recorder 170 returns the process to S202. As described above, the drive recorder 170 stores the time history data including the vehicle body speed and the measured acceleration measured within the predetermined time range from the time when the measured acceleration larger than the predetermined value is measured, into the memory card. Record at 178. In the following description, when the term “the above time range” is simply used, the term means the above “predetermined time range from the time when the measured acceleration larger than the predetermined value is measured”. Is pointed to.

  In addition, when the vehicle 160 ends operation, the memory card 178 is brought into the user terminal 150 by the user. The user terminal 150 reads the measurement data recorded on the memory card 178 and transmits it to the driving analysis device 110 via the network 140.

  FIG. 3 shows an example of a block configuration of the driving analysis device 110. The driving analysis device 110 includes a time history acquisition unit 300, a long-term measurement acceleration calculation unit 310, a period identification unit 320, a subtraction acceleration calculation unit 330, a long-term acceleration calculation unit 340, a differential acceleration calculation unit 350, a fluctuation range calculation unit 360, and a weight calculation. A unit 370, a weighted acceleration calculation unit 380, and a driving analysis unit 390.

  The time history acquisition unit 300 acquires measurement data recorded in the memory card 178 from the user terminal 150 as time history data. For example, the time history acquisition unit 300 acquires time history data through the network 140. As described above, the time history acquisition unit 300 acquires time history data including the speed and measured acceleration of the vehicle body measured within the time range.

  The period specifying unit 320 specifies a period for calculating an acceleration offset (hereinafter abbreviated as an offset calculation period) based on the time history data. Specifically, the period specifying unit 320 specifies a period in which the temporal change amount of the speed is smaller than a predetermined value from the time history data within the time range. Here, the “predetermined value” may be a predetermined threshold Tv used when the offset calculation period is determined based on the speed. In addition, as an example of the temporal change amount of the speed, an absolute value of a time differential value of the speed of the vehicle 160 can be used as an index. For example, the period specifying unit 320 specifies a period in which the absolute value of the time differential value of the speed is smaller than the threshold value Tv.

  The subtraction acceleration calculation unit 330 calculates the corrected acceleration corrected by subtracting the offset from the measured acceleration. Specifically, the subtraction acceleration calculation unit 330 calculates a subtraction acceleration obtained by subtracting the measurement acceleration within the period specified by the period specification unit 320 from the measurement acceleration included in the time history data as a corrected acceleration. To do. For example, the subtraction acceleration calculation unit 330 may calculate the corrected acceleration by subtracting the average value of the measurement acceleration within the period specified by the period specifying unit 320 from the measurement acceleration included in the time history data.

  Here, consider a case where the vehicle 160 suddenly decelerates while traveling on a slope. Here, it is assumed that the slope is already approaching 6 seconds before sudden deceleration. In this case, a value corresponding to the slope of the hill is added as an offset to the measured acceleration included in the time history data. If an attempt is made to evaluate the level of dangerous driving using such measured acceleration, it may be evaluated including an offset and cannot be evaluated properly.

  Even when the acceleration sensor 172 is not properly initialized, a measured acceleration with an offset value added may be obtained. For example, even if the output from the acceleration sensor 172 is initially set to indicate zero acceleration on a relatively flat road surface, if the road surface is not completely flat, an offset value corresponding to the slope of the road surface at the initial setting is set. Will be added to the measured acceleration.

  On the other hand, according to the driving analysis apparatus 110 of the present embodiment, the subtraction acceleration calculation unit 330 calculates a corrected acceleration obtained by subtracting the measurement acceleration within the offset calculation period from the measurement acceleration. Thereby, it is possible to obtain a corrected acceleration in which the offset value of the acceleration according to the slope of the slope is corrected. By using this corrected acceleration, for example, even when the vehicle is suddenly decelerated on a slope, the level of dangerous driving can be appropriately evaluated from the time history data.

  The period specifying unit 320 includes a period in which the temporal change amount of the speed is smaller than a predetermined value and the temporal change amount of the measured acceleration is smaller than the predetermined value within the time range. You may specify. Here, the “predetermined value” corresponding to the temporal change amount of the measured acceleration may be a predetermined threshold Ta used when the offset calculation period is determined based on the measured acceleration. Naturally, the threshold value Tv and the threshold value Ta may be different values.

  The long-term measurement acceleration calculation unit 310 calculates a time-averaged measurement acceleration. Specifically, long-term measurement acceleration calculation unit 310 calculates long-term measurement acceleration, which is an average value of measurement acceleration in a period longer than a predetermined time length, from time history data. For example, the long-term measurement acceleration calculation unit 310 may calculate the long-term measurement acceleration in a period longer than the time resolution of the time history data by moving average the measurement acceleration. For example, the long-term measurement acceleration calculation unit 310 may calculate the long-term measurement acceleration using a moving average of 20 samples before and after when 30 samples of measurement data are obtained per second.

  The number of measurement data samples and the number of moving average samples can be set freely, and are not limited to the above values. The long-term measurement acceleration corresponds to a low-frequency component included in the measurement acceleration, and is a concept including those calculated by various methods other than time averaging processing such as moving average.

  Then, the period specifying unit 320 has a temporal change amount of speed smaller than a predetermined value within the above time range, and a temporal change amount of measurement acceleration is smaller than a predetermined value, and A period in which the temporal change amount of the long-term measurement acceleration is smaller than a predetermined value may be specified. Here, the “predetermined value” for the temporal change amount of the long-term measurement acceleration may be a predetermined threshold Taav used when the offset calculation period is determined based on the long-term measurement acceleration. Of course, the threshold value Tv, the threshold value Ta, and the threshold value Taav may be different from each other.

  Note that the subtraction acceleration calculation unit 330 may calculate the corrected acceleration by subtracting the average value of the long-term measurement acceleration from the measurement acceleration. As described above, by calculating the average value of the long-term measurement acceleration within the offset calculation period in which the long-term measurement acceleration is constant in time as the offset value to be subtracted from the measurement acceleration, an appropriate offset for the measurement acceleration Can be processed.

  As described above, the processing block A including the long-term measurement acceleration calculation unit 310, the period specifying unit 320, and the subtraction acceleration calculation unit 330, and the time history acquisition unit 300 calculate the corrected acceleration by correcting the measurement acceleration. It can function as an acceleration calculation device. The corrected acceleration calculated by the subtraction acceleration calculation unit 330 is supplied to the processing block B including the long-term acceleration calculation unit 340, the differential acceleration calculation unit 350, the fluctuation range calculation unit 360, the weight calculation unit 370, and the weighted acceleration calculation unit 380. Is done. In the processing block B, an acceleration in which the influence of unevenness on the road surface such as a step is reduced with respect to the corrected acceleration is calculated.

  The long-term acceleration calculation unit 340 calculates a long-term acceleration that is an average value of the subtraction acceleration over a period longer than a predetermined time length. The long-term acceleration calculation unit 340 can calculate the long-term acceleration by performing the same process as the process by the subtraction acceleration calculation unit 330 on the subtraction acceleration. In this case as well, as with the long-term measured acceleration, the long-term acceleration corresponds to the low-frequency component included in the subtraction acceleration, and is calculated by various methods other than time averaging processing such as moving average. It is a concept that includes.

  The weighted acceleration calculating unit 380 calculates the acceleration calculated by weighting the long-term acceleration and the measured acceleration as, for example, a corrected acceleration used for evaluating dangerous driving. As described below, the weight is calculated by the weight calculation unit 370 based on the calculation results in the differential acceleration calculation unit 350 and the fluctuation range calculation unit 360.

  The differential acceleration calculation unit 350 calculates the differential acceleration obtained by subtracting the long-term acceleration from the subtraction acceleration. Here, the differential acceleration corresponds to a high frequency component included in the subtraction acceleration, and is a concept including those calculated by various methods other than the subtraction process.

  The fluctuation range calculation unit 360 calculates the fluctuation range of the subtraction acceleration within the time range and the fluctuation range of the differential acceleration within the time range. For example, as the fluctuation range, a value obtained by subtracting the minimum value from the maximum value of the subtraction acceleration, that is, the amplitude of the subtraction acceleration can be exemplified.

  The weight calculation unit 370 calculates a greater weight for the subtraction acceleration than the long-term acceleration as the ratio of the subtraction acceleration fluctuation range to the differential acceleration fluctuation range is larger. The weighted acceleration calculation unit 380 calculates a weighted acceleration obtained by weighting the subtraction acceleration and the long-term acceleration with the weight calculated by the weight calculation unit 370 as a corrected acceleration.

  The driving analysis unit 390 analyzes driving using the corrected acceleration calculated by the weighted acceleration calculation unit 380. For example, the driving analysis unit 390 may calculate a driving roughness level. The driving analysis unit 390 may analyze driving analysis using speed, brake information, blinker information, and image data included in the time history data in addition to the corrected acceleration. The driving analysis unit 390 records the driving evaluation result in the analysis result DB 120.

  Here, an example of the effect obtained by the weighting process will be briefly described. Here, the case where it is drive | working the road surface with a level | step difference is considered. In this case, the measurement acceleration has a relatively high frequency and randomly changing waveform. In this case, the long-term acceleration has a relatively small waveform. For this reason, the amplitude of the differential acceleration is not significantly smaller than the amplitude of the measured acceleration. In this case, since the ratio of the fluctuation range is calculated to be relatively small (for example, a value close to 1 is calculated), the weight for the long-term acceleration is calculated to be large. As a result, driving is evaluated mainly using long-term acceleration.

  In this case, driving is evaluated using long-term acceleration from which random waveform components due to road surface steps are removed. Therefore, it is possible to appropriately evaluate the driving roughness using the long-term acceleration by setting the period for averaging the measured acceleration to an appropriate time length so that the driving roughness is reflected in the long-term acceleration. it can.

  Note that the fluctuation range calculation unit 360 may further calculate a positive fluctuation range and a negative fluctuation range for the differential acceleration. Then, the weight calculation unit 370 may calculate the weight based on the fluctuation range in the positive direction and the fluctuation range in the negative direction. This process will be described in more detail with reference to FIG.

  In the above description, the subtraction acceleration calculated by the subtraction acceleration calculation unit 330 is input to the processing block B, and the processing block B corrects the subtraction acceleration. In another form, the measured acceleration acquired by the time history acquisition unit 300 may be input to the processing block B. In this case, the driving analysis unit 390 can evaluate driving using the acceleration obtained by subtracting the offset from the weighted acceleration afterwards. As described above, the processing block B and the time history acquisition unit 300 can also function as an acceleration calculation device that calculates a corrected acceleration obtained by correcting the measured acceleration. In addition, if it is known in advance that there is no offset in the measured acceleration, the driving analysis unit 390 can evaluate driving using the weighted acceleration obtained by the weighted acceleration calculating unit 380 as it is.

  According to the driving analysis device 110, the risk level of driving can be evaluated by using the absolute value of acceleration by offset correction, so that the driving risk level can be stably calculated. In addition, since the driving can be evaluated using the acceleration value from which the influence caused by the road surface unevenness is removed, the driving danger level can be appropriately evaluated.

  FIG. 4 shows an example of a processing flow in which the driving analysis device 110 calculates the subtraction acceleration. In S402, one piece of time history data is acquired from a plurality of time history data of different periods.

  In S404, the period specifying unit 320 determines whether there is an effective offset calculation period. As described above, the period specifying unit 320 determines whether or not there is a period in which at least the speed is constant.

  If it is determined in S404 that an effective offset calculation period exists, in S406, the subtraction acceleration calculation unit 330 calculates an acceleration offset value. As described above, the subtraction acceleration calculation unit 330 calculates, as an acceleration offset value, an average value of measured acceleration or long-term measured acceleration in an offset calculation period in which at least the speed is constant.

  In step S <b> 408, the subtraction acceleration calculation unit 330 determines whether the acceleration offset value is valid. For example, the subtraction acceleration calculation unit 330 determines whether or not the calculated offset value of the acceleration is an appropriate size.

  If it is determined in S408 that the acceleration offset value is valid, the subtraction acceleration calculation unit 330 calculates the subtraction acceleration by subtracting the offset value from the measured acceleration in S412. Then, the subtraction acceleration calculation unit 330 outputs the subtraction acceleration to the processing block B. Moreover, the subtraction acceleration calculation part 330 may output subtraction acceleration to analysis result DB120.

  If it is determined in S404 that there is no valid offset calculation period, or if it is determined in S408 that the offset value is not valid, the process proceeds to S410. In S410, the subtraction acceleration calculation unit 330 calculates the average value of the waveform data of all measured accelerations obtained from the same vehicle 160 as an offset value, and advances the process to S412.

  FIG. 5 shows an example of a processing flow in which the driving analysis device 110 corrects the subtraction acceleration. In S502, each part of the processing block B acquires the calculated subtraction acceleration.

  In S504, the long-term acceleration calculation unit 340 calculates the long-term acceleration by, for example, averaging the subtraction acceleration. In S506, the differential acceleration calculation unit 350 calculates the differential acceleration between the subtraction acceleration and the long-term acceleration. In S508, the fluctuation range calculation unit 360 calculates a fluctuation range such as the amplitude value of the differential acceleration.

  The weight calculation unit 370 calculates a swing degree initial value v0 based on the amplitude value of the differential acceleration. Specifically, the weight calculation unit 370 calculates the initial value of swing v0 smaller when the ratio of the fluctuation width of the subtraction acceleration to the fluctuation width of the differential acceleration is larger. For example, when the ratio of the fluctuation range is 2 or more, the weight calculation unit 370 calculates the swing degree initial value v0 as 0%. Further, when the ratio of the fluctuation ranges is 1, the weight calculation unit 370 calculates the initial swing value v0 as 100%. When the ratio of the fluctuation ranges is the intermediate value, the weight calculation unit 370 calculates a swing degree initial value v0 between 0% and 100% according to the fluctuation ratio.

  As an example, when the waveform of the measured acceleration is a random vibration waveform, such as when the vehicle 160 is traveling on a level difference, a sway degree initial value v0 close to 100% is calculated. On the other hand, when the change in the waveform of the measured acceleration is gradual, such as when the vehicle 160 is accelerating moderately, a swaying degree initial value v0 close to 0% is calculated.

  In S512, the fluctuation range calculation unit 360 further calculates a fluctuation range for each sign of the differential acceleration with respect to the differential acceleration. Specifically, the fluctuation range calculation unit 360 includes a positive direction fluctuation range that is a fluctuation range of the differential acceleration in a period in which the sign of the differential acceleration is positive, and a differential acceleration in a period in which the sign of the differential acceleration is negative. The fluctuation range in the negative direction, which is the fluctuation range, is further calculated. More specifically, the fluctuation range calculation unit 360 calculates the maximum value of the differential acceleration as the positive direction fluctuation range, and calculates the absolute value of the minimum value of the differential acceleration as the negative direction fluctuation range.

  In S514, the weight calculation unit 370 calculates the degree of bias y as the difference between the positive direction fluctuation range and the negative direction fluctuation range increases. For example, when one of the positive direction fluctuation range and the negative direction fluctuation range has a magnitude three times or more of the other, the degree of bias y is calculated as 100%. When the ratio between the positive direction fluctuation range and the negative direction fluctuation range is 1, the degree of bias y is calculated as 0%. When the difference between the positive direction fluctuation range and the negative direction fluctuation range is the intermediate value, the weight calculation unit 370 determines between 0% and 100% depending on the ratio of the positive direction fluctuation range and the negative direction fluctuation range. The degree of bias y is calculated.

  Then, the weight calculation unit 370 calculates the final degree of shaking v. Specifically, the weight calculation unit 370 is v = v0 × (1-y). As described above, the weight calculation unit 370 calculates a smaller swing degree v as the swing degree initial value v0 is smaller. In addition, the weight calculation unit 370 calculates a smaller swing degree v as the degree of bias y is larger.

  In S516, a corrected acceleration obtained by correcting the subtraction acceleration is calculated. Specifically, the weight calculation unit 370 calculates the weight of the measured acceleration larger than the long-term acceleration as the degree of shaking v is smaller. Then, the weighted acceleration calculating unit 380 calculates a weighted acceleration obtained by weighting the measured acceleration and the long-term acceleration with the above weight. In S518, the weighted acceleration calculation unit 380 outputs the calculated weighted acceleration as a corrected acceleration.

  Here, the effect of the degree of bias y on the weighted acceleration will be briefly described by taking as an example the case of traveling on a road surface having a level difference. As described above, since the measured acceleration waveform is a random waveform, the long-term acceleration amplitude is relatively small. For this reason, the waveform of the differential acceleration between the measured acceleration and the long-term acceleration is a waveform that has the same amplitude in both positive and negative directions. For this reason, a relatively small value is calculated as the degree of bias y. As a result, the degree of shaking v is calculated to be relatively large, and a corrected acceleration in which the long-term acceleration is more heavily weighted is obtained.

  Next, consider a case where rough driving is performed, such as when the driver suddenly accelerates or decelerates. Even in this case, the measurement acceleration of the oscillating waveform can be obtained, but the acceleration amount and the deceleration amount are often not substantially equal on a long time scale compared to the time variation due to the step. For this reason, the differential acceleration often has a waveform in which the magnitude differs between the positive amplitude and the negative amplitude.

  In this case, a relatively large value (for example, a value close to 100%) is calculated as the degree of bias y. As a result, the degree of shaking v is calculated to be relatively small, and a corrected acceleration in which the measured acceleration is weighted more is obtained. Thereby, since driving | running | working is evaluated using the correction | amendment acceleration with which measurement acceleration was weighted comparatively largely, the roughness of driving | running | working can be evaluated appropriately.

  As described above, the weight calculation unit 370 has a larger ratio of the fluctuation width of the subtraction acceleration to the fluctuation width of the differential acceleration, and the greater the difference between the positive fluctuation width and the negative fluctuation width, the greater the long-term acceleration. A larger weight is calculated. Thereby, it is possible to calculate the corrected acceleration in which the influence due to the step included in the measured acceleration is reduced. Thereby, the roughness of driving | running can be evaluated appropriately using correction | amendment acceleration.

  In the above description, the corrected acceleration is calculated by the weighting process based on the sway degree initial value v0 and the bias degree y. However, in other embodiments, the weight based on the bias degree y is not considered without considering the sway degree initial value v0. The corrected acceleration may be calculated by the attaching process. That is, the weight calculation unit 370 calculates a greater weight for the measured acceleration than the long-term acceleration as the difference between the positive direction fluctuation range and the negative direction fluctuation range is larger. Then, the weighted acceleration calculation unit 380 calculates the weighted acceleration obtained by weighting the subtraction acceleration and the long-term acceleration with the weight calculated by the weight calculation unit 370 as the corrected acceleration. As is apparent from the above description, there are cases where the roughness of driving can be properly evaluated even when the corrected acceleration based on the degree of bias y is used.

  FIGS. 6 to 9 schematically show an example waveform of measured acceleration and an example waveform of acceleration corrected by the driving analysis device 110. FIG. 6 schematically shows an example of measured acceleration and subtraction acceleration obtained by offset correction.

  A graph 600 shows an example of the time evolution (waveform 601) of the measured acceleration included in one time history data. A graph 610 shows an example of the time evolution (waveform 611) of the speed included in one time history data and the time evolution (waveform 612) of the long-term measurement acceleration calculated by the long-term acceleration calculation unit 340. A graph 620 shows an example of the time evolution (waveform 621) of the subtraction acceleration. In the graph 600, the graph 610, and the graph 620, the normalized time is plotted on the horizontal axis, and the normalized speed or acceleration of the vehicle 160 is plotted on the vertical axis.

  The period specifying unit 320 specifies the period 651, the period 652, and the period 653, which are periods in which the speed is substantially constant, and determines these periods as offset calculation period candidates. As indicated by the waveform 611, the speed is substantially constant during these periods.

  The period specifying unit 320 determines a period 654 in which the measurement acceleration and the long-term measurement acceleration are substantially constant from the period 651, the period 652, and the period 653 as an offset calculation period. Then, the subtraction acceleration calculation unit 330 calculates the average value of the long-term measurement acceleration in the offset calculation period as the acceleration offset value. In the example of this figure, −0.2 is calculated as the acceleration offset value. Then, the subtraction acceleration calculation unit 330 calculates the subtraction acceleration by subtracting the acceleration offset value from the measured acceleration. As shown in the graph 620, the subtraction acceleration waveform 621 is a waveform with 0 as the base point, and it can be seen that the offset processing is appropriately performed.

  In addition, when a plurality of different periods are specified as the offset calculation period from the time range recorded as the time history data, the period specifying unit 320 specifies one or more decimals of the plurality of periods. This period may be selected as the offset calculation period. For example, the period specifying unit 320 may select a period closer to the period in which sudden acceleration / deceleration has occurred, with higher priority as the offset calculation period. As an example, the period specifying unit 320 may select a period closer to the center in the time range with higher priority as the offset calculation period.

  For example, if the vehicle 160 has suddenly accelerated or decelerated after entering a slope, measurement data in the time range from 12 seconds before to 6 seconds after the sudden acceleration / deceleration is recorded in the time history data think of. Assuming that the vehicle 160 has not yet reached the slope at the time point 12 seconds ago, when the offset value is calculated from the measured acceleration at the time point 12 seconds ago, an undesirable offset value is calculated. By setting the period closer to the center in the above time range as the period for calculating the offset, the offset value can be calculated from the period closer to the point at which sudden acceleration / deceleration is actually performed. In addition, among the specified periods as the offset calculation period, the period specifying unit 320 selects a part of the period closer to the period in which sudden acceleration / deceleration has occurred, with higher priority as the offset calculation period. Also good.

  FIGS. 7 to 9 schematically show a waveform example of acceleration of three patterns to be corrected and a corrected waveform example of corrected acceleration. Here, it is assumed that the acceleration to be corrected is the subtraction acceleration subjected to the above-described offset processing.

  FIG. 7 schematically shows an example of a subtraction acceleration waveform to be corrected. A waveform 701 in the graph 700 shows an example of a waveform of the subtraction acceleration when the vehicle is slowly decelerated on a flat road surface without a step. In the graphs shown in FIGS. 7 to 9, the normalized time is taken on the horizontal axis, and the normalized acceleration is taken on the vertical axis.

  A waveform 702 in the graph 700 indicates long-term acceleration obtained by moving and averaging the subtraction acceleration. A waveform 711 in the graph 710 indicates a differential acceleration between the subtraction acceleration and the long-term acceleration. The amplitude of the differential acceleration waveform 711 is approximately 0.21, which is significantly smaller than the amplitude (approximately 0.6) of the waveform 701. In this case, 0 is calculated as the initial swing value v0, and the final swing v is 0. As a result, the weight calculation unit 370 calculates 100% weighting for the subtraction acceleration and 0% weighting for the long-term acceleration, and the weighting acceleration calculation unit 380 calculates the subtraction acceleration as the corrected acceleration.

  A waveform 721 in the graph 720 indicates a waveform of the corrected acceleration. As described above, in this case, the corrected acceleration and the subtraction acceleration are the same. For this reason, since the driving | running analysis part 390 will analyze and evaluate a driving | operation from the subtraction acceleration in which the driving | running roughness is reflected, it can evaluate driving | running roughness appropriately. The positive amplitude (positive direction change amount) and negative direction amplitude (negative direction change amount) of the differential acceleration are about 0.11 and 0.1, respectively, and the degree of bias y is about 0.05. Calculated. However, since the sway degree initial value v0 is 0, the bias degree y does not affect the final sway degree v.

  FIG. 8 schematically shows another example of the subtraction acceleration waveform. A waveform 701 in the graph 700 shows an example of a waveform of a subtraction acceleration obtained when the vehicle is driven on a road with a step without intense acceleration / deceleration.

  A waveform 802 in the graph 800 shows a long-term acceleration obtained by moving and averaging the subtraction acceleration. A waveform 811 in the graph 810 indicates a differential acceleration between the subtraction acceleration and the long-term acceleration. The amplitude of the differential acceleration waveform 811 is approximately 1.37, which is relatively close to the amplitude of the waveform 801 (approximately 1.43). In this case, the shaking degree initial value v0 is approximately 0.96, which is a value close to 1.

  The positive amplitude (positive direction change amount) and negative direction amplitude (negative direction change amount) of the differential acceleration are approximately 0.69 and 0.68, respectively. In this case, the bias degree y is calculated as a remarkably small value of about 0.01. As a result, the final degree of shaking v is approximately 0.95, which is a value close to 1.

  As a result, the weight calculation unit 370 calculates the weight for the subtraction acceleration as about 5% and the weight for the long-term acceleration as about 95%. The weighted acceleration calculation unit 380 weights the subtraction acceleration and the long-term acceleration with this weighting, and calculates the corrected acceleration.

  A waveform 821 of the graph 820 indicates a waveform of the corrected acceleration. In this case, since the weighting for the subtraction acceleration is only about 5%, the corrected acceleration substantially matches the long-term acceleration. For this reason, a waveform having a significantly reduced amplitude compared to the subtraction acceleration can be obtained as the corrected acceleration waveform. As described above, the weighted acceleration calculation unit 380 outputs the corrected acceleration from which the influence of the step is substantially removed. The driving analysis unit 390 analyzes and evaluates driving from the corrected acceleration from which the influence of the step is substantially removed. For this reason, it can prevent beforehand that the acceleration level by a level | step difference is reflected in the roughness level of a driving | operation as it is, and the roughness of a driving | operation can be evaluated appropriately.

  FIG. 9 schematically shows still another example of the waveform of the subtraction acceleration. A waveform 901 of the graph 900 shows an example of a waveform of the subtraction acceleration that is accelerated and decelerated intensely by the driver.

  A waveform 902 of the graph 900 indicates a long-term acceleration obtained by moving and averaging the subtraction acceleration. A waveform 911 in the graph 910 indicates a differential acceleration between the subtraction acceleration and the long-term acceleration. The subtraction acceleration waveform 901 has an amplitude of approximately 1.43, and the differential acceleration waveform 911 has an amplitude of approximately 1.12. In this case, the initial swing value v0 is calculated as approximately 0.62.

  A positive amplitude (amount of change in the positive direction) and a negative direction amplitude (amount of change in the negative direction) of the differential acceleration are approximately 0.62 and 0.23, respectively. A value close to 1 is calculated. As a result, the final degree of shaking v is approximately 0.09, which is a value close to 0.

  As a result, the weight calculation unit 370 calculates the weight for the subtraction acceleration as approximately 91% and the weight for the long-term acceleration as approximately 9%. The weighted acceleration calculation unit 380 weights the subtraction acceleration and the long-term acceleration with this weighting, and calculates the corrected acceleration.

  A waveform 921 of the graph 920 indicates a waveform of the corrected acceleration. In this case, since the weighting for the long-term acceleration is only about 9%, the corrected acceleration substantially matches the subtraction acceleration. In this manner, the weighted acceleration calculation unit 380 outputs a corrected acceleration that reflects the roughness of driving. Since the driving analysis unit 390 analyzes and evaluates driving based on the corrected acceleration in which the driving roughness is reflected, the driving roughness can be appropriately evaluated.

  In this case, a relatively large value (approximately 0.62) is calculated as the initial swing value v0. However, by calculating a relatively large value (approximately 0.85) for the degree of bias y, finally, the weight of the subtraction acceleration is relatively large compared to the long-term acceleration. In this way, by considering the degree of bias y, a significantly different degree of sway v can be obtained when the vehicle is simply traveling on a level difference and when it is vigorously accelerated or decelerated. As a result, when the vehicle is simply running on a level difference, the driving roughness is substantially evaluated by the long-term acceleration, and when the vehicle is accelerating or decelerating severely, the driving roughness is substantially evaluated by the subtraction acceleration. .

  Here, a case where acceleration / deceleration is intensely performed on a road surface with a level difference is considered. As described with reference to FIG. 8, with respect to the acceleration fluctuation component due to the step, it is possible to obtain a corrected acceleration in which the fluctuation is appropriately removed. On the other hand, as described with reference to FIG. 9, with respect to a fluctuation component caused by intense acceleration / deceleration, a corrected acceleration in which the fluctuation is appropriately taken into account can be obtained. Thus, according to the driving | running analysis apparatus 110, the roughness of driving | operation irrespective of the presence or absence of a level | step difference can be evaluated appropriately.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above-described embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The order of execution of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior to”. It should be noted that the output can be realized in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for convenience, it means that it is essential to carry out in this order. It is not a thing.

100 driving analysis system, 110 driving analysis device, 120 analysis result DB, 140 network, 150 user terminal, 160 vehicle, 170 drive recorder, 172 acceleration sensor, 174 camera, 176 CPU, 178 memory card, 182 speed sensor, 184 brake sensor 186 Winker sensor, 190 recording medium, 300 time history acquisition unit, 310 long-term measurement acceleration calculation unit, 320 period specifying unit, 330 subtraction acceleration calculation unit, 340 long-term acceleration calculation unit, 350 differential acceleration calculation unit, 360 fluctuation range calculation unit 370 Weight calculation unit, 380 Weighted acceleration calculation unit, 390 Driving analysis unit, 600, 610, 620 graph, 601, 611, 612, 621 waveform, 651, 652, 653, 654 period, 700, 710, 7 0 graph, 701,702,711,721 waveform, 800,810,820 graph, 801,802,811,821 waveform, 900,910,920 graph, 901,902,911,921 waveform

Claims (13)

An acceleration calculating device that calculates a corrected acceleration by correcting a measured acceleration that is a measured acceleration of a vehicle body,
A time history acquisition unit for acquiring time history data including the measured acceleration measured within a predetermined time range from the time when the measured acceleration greater than a predetermined value is measured;
A long-term acceleration calculator that calculates a long-term acceleration that is an average value of the measured acceleration in a period longer than a predetermined time length;
A differential acceleration calculator for calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration;
A positive direction fluctuation range that is a fluctuation range of the differential acceleration in a period in which the sign of the differential acceleration is positive, and a negative direction fluctuation that is a fluctuation range of the differential acceleration in a period in which the sign of the differential acceleration is negative A fluctuation range calculator for calculating the width;
A weight calculation unit that calculates a greater weight for the measured acceleration than the long-term acceleration, as the difference between the positive direction fluctuation range and the negative direction fluctuation range is larger;
An acceleration calculation apparatus comprising: a weighted acceleration calculation unit that calculates a weighted acceleration obtained by weighting the measured acceleration and the long-term acceleration with the weight calculated by the weight calculation unit as the corrected acceleration. The fluctuation range calculation unit further calculates a fluctuation range of the measured acceleration within the time range and a fluctuation range of the differential acceleration within the time range,
The weight calculation unit has a larger difference between the positive direction fluctuation range and the negative direction fluctuation range, and the larger the ratio of the measurement acceleration fluctuation range to the differential acceleration fluctuation range, the larger the long-term acceleration to the measurement acceleration. The acceleration calculating apparatus according to claim 1, wherein the acceleration is calculated to be larger. The time history acquisition unit acquires the time history data further including the speed of the vehicle body measured within the time range from the time when the measured acceleration greater than the predetermined value is measured,
The acceleration calculation device includes:
A period specifying unit that specifies a period in which the temporal change amount of the speed is smaller than a predetermined value within the time range from the time history data;
A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measurement acceleration within the period specified by the period specification unit from the measurement acceleration included in the time history data;
The long-term acceleration calculation unit calculates an average value of the subtraction acceleration in a period longer than a predetermined time length as the long-term acceleration,
The differential acceleration calculation unit calculates the differential acceleration by subtracting the long-term acceleration from the subtraction acceleration,
The fluctuation range calculation unit calculates a fluctuation range of the subtraction acceleration within the time range, and from the differential acceleration obtained from the subtraction acceleration, the positive direction fluctuation range, the negative direction fluctuation range, and the Calculate the fluctuation range of the differential acceleration within the time range,
The weight calculation unit has a large difference between the positive direction fluctuation range obtained from the subtraction acceleration and the negative direction fluctuation range obtained from the subtraction acceleration, and the fluctuation range of the differential acceleration obtained from the subtraction acceleration. The greater the ratio of the fluctuation range of the subtraction acceleration to the greater, the greater the weight for the subtraction acceleration than the long-term acceleration,
The acceleration calculation apparatus according to claim 2, wherein the weighted acceleration calculation unit calculates a weighted acceleration in which the subtraction acceleration and the long-term acceleration are weighted with the weight calculated by the weight calculation unit as the corrected acceleration. . The time history acquisition unit acquires the time history data further including the speed of the vehicle body measured within the time range from the time when the measured acceleration greater than the predetermined value is measured,
The acceleration calculation device includes:
A period specifying unit that specifies a period in which the temporal change amount of the speed is smaller than a predetermined value within the time range from the time history data;
A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measurement acceleration within the period specified by the period specification unit from the measurement acceleration included in the time history data;
The long-term acceleration calculation unit calculates an average value of the subtraction acceleration in a period longer than a predetermined time length as the long-term acceleration,
The differential acceleration calculation unit calculates the differential acceleration by subtracting the long-term acceleration from the subtraction acceleration,
The fluctuation range calculation unit calculates the positive direction fluctuation range and the negative direction fluctuation range from the differential acceleration obtained from the subtraction acceleration,
The weight calculation unit increases the weight for the subtraction acceleration from the long-term acceleration as the difference between the positive direction fluctuation range obtained from the subtraction acceleration and the negative direction fluctuation range obtained from the subtraction acceleration is larger. Calculate
The acceleration calculation apparatus according to claim 1, wherein the weighted acceleration calculation unit calculates a weighted acceleration in which the subtraction acceleration and the long-term acceleration are weighted with the weight calculated by the weight calculation unit as the corrected acceleration. . An acceleration calculation method for calculating a corrected acceleration obtained by correcting a measured acceleration which is a measured acceleration of a vehicle body,
A time history acquisition step of acquiring time history data including the measured acceleration measured within a predetermined time range from the time when the measured acceleration greater than a predetermined value is measured;
A long-term acceleration calculating step of calculating a long-term acceleration that is an average value of the measured acceleration in a period longer than a predetermined time length;
A differential acceleration calculating step of calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration;
A positive direction fluctuation range that is a fluctuation range of the differential acceleration in a period in which the sign of the differential acceleration is positive, and a negative direction fluctuation that is a fluctuation range of the differential acceleration in a period in which the sign of the differential acceleration is negative A fluctuation range calculation stage for calculating the width,
A weight calculation step of calculating a greater weight for the measured acceleration than the long-term acceleration, as the difference between the positive direction fluctuation range and the negative direction fluctuation range is larger.
An acceleration calculation method comprising: a weighted acceleration calculation step of calculating a weighted acceleration obtained by weighting the measured acceleration and the long-term acceleration with the weight calculated in the weight calculation step as the corrected acceleration. An acceleration calculating device that calculates a corrected acceleration by correcting a measured acceleration that is a measured acceleration of a vehicle body,
A time history acquisition unit for acquiring time history data including the measured acceleration measured within a predetermined time range from the time when the measured acceleration greater than a predetermined value is measured;
A long-term acceleration calculator that calculates a long-term acceleration that is an average value of the measured acceleration in a period longer than a predetermined time length;
A differential acceleration calculator for calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration;
A fluctuation range calculating unit that calculates a fluctuation range of the measured acceleration within the time range and a fluctuation range of the differential acceleration within the time range;
A weight calculation unit that calculates a greater weight for the measured acceleration than the long-term acceleration, as the ratio of the measured acceleration fluctuation width to the differential acceleration fluctuation width is larger;
An acceleration calculation apparatus comprising: a weighted acceleration calculation unit that calculates a weighted acceleration obtained by weighting the measured acceleration and the long-term acceleration with the weight calculated by the weight calculation unit as the corrected acceleration. The time history acquisition unit acquires the time history data further including the speed of the vehicle body measured within the time range from the time when the measured acceleration greater than the predetermined value is measured,
The acceleration calculation device includes:
A period specifying unit that specifies a period in which the temporal change amount of the speed is smaller than a predetermined value within the time range from the time history data;
A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measurement acceleration within the period specified by the period specification unit from the measurement acceleration included in the time history data;
The long-term acceleration calculation unit calculates an average value of the subtraction acceleration in a period longer than a predetermined time length as the long-term acceleration,
The differential acceleration calculation unit calculates the differential acceleration by subtracting the long-term acceleration from the subtraction acceleration,
The fluctuation range calculation unit calculates a fluctuation range of the subtraction acceleration within the time range, calculates a fluctuation range of the differential acceleration within the time range from the differential acceleration obtained from the subtraction acceleration,
The weight calculation unit calculates a greater weight for the subtraction acceleration than the long-term acceleration, as the ratio of the subtraction acceleration fluctuation range to the subtraction acceleration fluctuation range obtained from the subtraction acceleration increases.
The acceleration calculation apparatus according to claim 6, wherein the weighted acceleration calculation unit calculates a weighted acceleration in which the subtraction acceleration and the long-term acceleration are weighted by the weight calculated by the weight calculation unit as the corrected acceleration. . An acceleration calculation method for calculating a corrected acceleration obtained by correcting a measured acceleration which is a measured acceleration of a vehicle body,
A time history acquisition step of acquiring time history data including the measured acceleration measured within a predetermined time range from the time when the measured acceleration greater than a predetermined value is measured;
A long-term acceleration calculating step of calculating a long-term acceleration that is an average value of the measured acceleration in a period longer than a predetermined time length;
A differential acceleration calculating step of calculating a differential acceleration obtained by subtracting the long-term acceleration from the measured acceleration;
A fluctuation width calculating step of calculating a fluctuation width of the measured acceleration within the time range and a fluctuation width of the differential acceleration within the time range;
A weight calculation step of calculating a greater weight for the measured acceleration than the long-term acceleration, as the ratio of the measured acceleration fluctuation width to the differential acceleration fluctuation width is larger;
An acceleration calculation method comprising: a weighted acceleration calculation step of calculating a weighted acceleration obtained by weighting the measured acceleration and the long-term acceleration with the weight calculated in the weight calculation step as the corrected acceleration. An acceleration calculating device that calculates a corrected acceleration by correcting a measured acceleration that is a measured acceleration of a vehicle body,
A time history acquisition unit for acquiring time history data including the speed of the vehicle body and the measurement acceleration measured within a predetermined time range from a time when the measured acceleration greater than a predetermined value is measured;
A period specifying unit that specifies a period in which the temporal change amount of the speed is smaller than a predetermined value within the time range from the time history data;
A subtraction acceleration calculation unit that calculates a subtraction acceleration obtained by subtracting the measurement acceleration within the period specified by the period specification unit from the measurement acceleration included in the time history data as the correction acceleration. Acceleration calculation device. The period specifying unit includes a period within the time range in which a temporal change amount of the speed is smaller than a predetermined value and a temporal change amount of the measurement acceleration is smaller than a predetermined value. The acceleration calculation apparatus according to claim 3, 4, 7, or 9. A long-term measurement acceleration calculating unit that calculates a long-term measurement acceleration that is an average value of the measurement acceleration in a period longer than a predetermined time length from the time history data;
In the time range, the period specifying unit has a temporal change amount of the velocity smaller than a predetermined value, a temporal change amount of the measurement acceleration is smaller than a predetermined value, and The acceleration calculation apparatus according to claim 3, 4, 7, 9, or 10, wherein a period in which a temporal change amount of the long-term measurement acceleration is smaller than a predetermined value is specified. The subtracted acceleration calculating unit calculates the corrected acceleration by subtracting an average value of the measured accelerations within a period specified by the period specifying unit from the measured accelerations included in the time history data. The acceleration calculation apparatus according to 4, 7, 9, 10, or 11. An acceleration calculation method for calculating a corrected acceleration obtained by correcting a measured acceleration which is a measured acceleration of a vehicle body,
A time history acquisition step of acquiring time history data including the speed of the vehicle body and the measured acceleration measured within a predetermined time range from the time when the measured acceleration greater than a predetermined value is measured;
A period specifying step for specifying a period in which the temporal change amount of the speed is smaller than a predetermined value within the time range from the time history data;
A subtraction acceleration calculation step of calculating, as the corrected acceleration, a subtraction acceleration obtained by subtracting the measurement acceleration within the period specified in the period specification step from the measurement acceleration included in the time history data. Acceleration calculation method.

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