JP6553502B2 - Steering operation feeling evaluation device - Google Patents

Description

  The present invention relates to a technique for evaluating data that an operation result of an EPS (electric power steering system) device that assists a steering operation for determining a traveling direction of a traveling vehicle gives the steering operation feeling.

  There are many techniques for collecting / analyzing various data using a computer. For example, Patent Document 1 below discloses a technique of collecting numerical data obtained from each control device mounted on a vehicle by a computer, and using the result of analysis to utilize it for performance test of each control device.

JP-A-10-244926

  In the prior art such as Patent Document 1, data collected from each control device is often collected regardless of whether it is useful for the purpose of the collection. Therefore, since all collected data is an analysis target, the analysis efficiency may not necessarily be high. In particular, the highly instantaneous data such as the sensitivity data representing the operation feeling of the electric power steering apparatus does not always generate data useful for evaluating the operation feeling, so all the sensitivities are not always generated. Data is often collected, and therefore analysis efficiency tends to be low.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a technique capable of efficiently collecting target data to be evaluated among sensitivity data of an electric power steering apparatus.

  The steering operation feeling evaluation apparatus according to the present invention starts obtaining the sensitivity data when the steering force starts to change or the steering angle starts to change.

  According to the steering operation feeling evaluation apparatus according to the present invention, the sensitive data of the electric power steering apparatus can be collected under the condition suitable for the evaluation purpose. Therefore, the steering operation feeling of the electric power steering device can be efficiently evaluated.

It is a block diagram which shows the evaluation apparatus 200 and its periphery structure. It is a flowchart explaining the procedure in which the evaluation apparatus 200 acquires sensitive data. It is a flowchart explaining the procedure in which the analysis part 230 analyzes sensitive data. It is a flowchart explaining the procedure in which the evaluation part 240 evaluates analysis result data. It is a conceptual diagram which shows the process in which the evaluation part 240 evaluates analysis result data.

  FIG. 1 is a block diagram showing an evaluation apparatus 200 and its peripheral configuration according to the present invention. The evaluation device 200 is a device that evaluates the steering operation feeling of the electric power steering device provided in the vehicle 100. Hereinafter, configurations of the vehicle 100 and the evaluation apparatus 200 will be described.

  The vehicle 100 is a vehicle such as a passenger car or a construction vehicle that travels when the driver gets on and steers. The vehicle 100 includes a steering unit 110, a driving unit 120, a braking unit 130, various sensors 140, a controller 150, and a communication control unit 160.

  The steering unit 110 includes a steering mechanism that operates the traveling direction of the vehicle and an EPS (electric power steering system) device. The steering mechanism includes a motor that assists the rotation of the steering, a torque sensor that detects the torque of the steering shaft, and a steering angle sensor that detects the rotational angle of the steering.

  The steering unit 110 includes a handlebar at a rotatable steering unit that determines the traveling direction, and the driver holds the steering wheel with both hands and rotates the steering wheel. The steering unit is supported by a cylindrical shaft and rotates in the same direction as the rotation of the handlebar. The cylindrical shaft of the steering unit is provided with a torque sensor and a steering angle sensor. The torque sensor detects the rotational force (torque amount) of the cylindrical shaft. The steering angle sensor detects the angle (phase) of the cylindrical shaft. The detection value of each sensor is output to the controller 150.

  The drive unit 120 is a functional unit that gives a driving force to the vehicle 100, and includes, for example, an engine and a control unit thereof. The braking unit 130 is a functional unit that brakes traveling of the vehicle 100, and includes, for example, a brake device and a control unit thereof. The various sensors 140 are a vehicle speed sensor, an acceleration sensor, a skid sensor, and a group of sensors that detect the operating states of various devices mounted on the vehicle 100.

  The controller 150 is an electronic control unit (ECU) that controls the EPS device. The controller 150 calculates a current command value for the motor based on the torque amount acquired from the torque sensor. The controller 150 further calculates a calculation parameter of a noise filter to be applied to detection values from each sensor when driving the motor, and a PWM (Pulse Width Modulation) signal value to an inverter that drives the motor. The controller 150 further converts the mechanical angle of the handle to an electrical angle and corrects the phase shift between the mechanical angle and the electrical angle.

  The communication control unit 160 communicates with a device outside the vehicle 100 via a wired or wireless interface. The controller 150 transmits the data described above as sensitive data (data representing the steering operation feeling of the electric power steering apparatus) to the evaluation device 200 via the communication control unit 160. Specifically, (a) torque amount (steering force), (b) steering angle, (c) current command value, (d) operation parameter of noise filter, (e) PWM signal value, (f) mechanical angle, (G) Electrical angle, etc.

  The evaluation device 200 includes a UI (user interface) unit 210, a control unit 220, an analysis unit 230, an evaluation unit 240, a storage unit 250, a communication control unit 260, a display control unit 270, and a display unit 280.

  The UI unit 210 is a functional unit for inputting an operation instruction to the evaluation apparatus 200 using an operation device such as a keyboard, a mouse, and a touch panel. The display unit 280 is configured by a display device such as a liquid crystal display, and displays the results of processing by the analysis unit 230 and the evaluation unit 240 on a screen.

  The control unit 220 is a functional unit that controls the overall operation of the evaluation apparatus 200, and controls the analysis unit 230, the evaluation unit 240, and the communication control unit 260.

  The communication control unit 260 receives sensitive data from the communication control unit 160 and passes it to the control unit 220. The control unit 220 stores this in the storage unit 250. The control unit 220 passes the sensitive data stored in the storage unit 250 to the analysis unit 230. The analysis unit 230 analyzes the sensitive data according to the procedure described later, and stores the result in the storage unit 250 as analysis result data. The control unit 220 passes the analysis result data stored in the storage unit 250 to the evaluation unit 240. The evaluation unit 240 evaluates the analysis result data according to a procedure described later, and stores the result in the storage unit 250 as evaluation result data. Further, according to the procedure to be described later, a pickup table for screen display is created using the sensitive data and the evaluation result data stored in the storage unit 250, and the pickup table is displayed by the display unit 280 via the display control unit 270. Display the screen.

  FIG. 2 is a flowchart for explaining a procedure by which the evaluation apparatus 200 acquires sensitive data. Hereinafter, each step of FIG. 2 will be described.

(FIG. 2: Step S201)
The controller 150 receives the signal that the ignition is turned on and the signal that the engine has started rotating from the controller of the driving unit 120 via, for example, a CAN (Controller Area Network), so that the vehicle 100 can travel. Recognize that it has become a state. This starts the flowchart.

(FIG. 2: Step S202)
It is desirable that the evaluation device 200 acquire only the sensitive data necessary to evaluate the steering operation feeling of the electric power steering device. That is, it is desirable to acquire only the sensitive data when the steering unit 110 is rotating. Thus, the controller 150 obtains the torque amount (steering force) or the steering angle of the steering unit from the corresponding sensor, and recognizes that the steering unit 110 starts to rotate when these start to change. If it is recognized that the steering unit 110 has started to rotate, the process proceeds to step S203. Otherwise, the process waits for start of rotation.

(FIG. 2: Step S202: Supplement 1)
When the handlebar is stationary, it is considered that the vehicle 100 is traveling straight or not traveling. In such a case, the sensitive data is not acquired by continuing this step. On the other hand, even if the vehicle speed of the vehicle 100 is 0 km / h, the steering operation can be performed, so it is desirable to start acquisition of the sensitive data triggered by the rotation of the steering unit 110.

(FIG. 2: Step S202: Supplement 2)
In this step, if it is considered that the steering unit 110 starts to rotate even if the torque amount or the steering angle changes only slightly, the start of rotation may be erroneously detected due to minute fluctuations in signal value, noise, or the like. There is also. Therefore, for example, the start of rotation of the steering unit 110 may be detected based on whether the amount of change in torque amount or steering angle per unit time is equal to or greater than a predetermined threshold.

(FIG. 2: Step S203)
The controller 150 starts collecting sensitivity data. The collection period may be, for example, according to the update period of the RAM (Random Access Memory) of the microcomputer mounted on the controller 150. Although the individual data items (for example, torque amount, steering angle, etc.) included in the sensitive data may have different update cycles from one another, the consistency of each data is ensured if, for example, the current indication value for the motor is determined. Be done. The reason for finally determining the steering operation feeling of the electric power steering apparatus is because the motor that drives the steering unit. Therefore, what is necessary is just to collect sensitivity data at the timing.

(FIG. 2: Step S204)
The controller 150 transmits the collected sensitivity data to the evaluation device 200. For example, this is passed to the communication control unit 160 at the same timing as the controller 150 collects the sensitive data, and the communication control unit 160 transmits this to the communication control unit 260 of the evaluation device 200.

(FIG. 2: Step S204: Supplement 1)
The communication control unit 160 can read sensitive data from the RAM without interrupting control processing of the controller 150 by using DMA (Direct Memory Access) included in the microcomputer of the controller 150. Thus, the communication control unit 160 can transmit the sensitive data smoothly.

(FIG. 2: Step S204: Supplement 2)
Each time the communication control unit 260 receives the sensitive data from the communication control unit 160, the communication control unit 260 stores this as one record in the storage unit 250. The value of each data item (torque amount, steering angle, etc.) at a certain acquisition timing is recorded in one record. For example, when a plurality of records are arranged along the time axis, a change with time of each data item can be obtained.

(FIG. 2: Step S205)
Since the controller 150 starts collecting the sensitive data as the steering unit 110 starts to rotate, it is desirable that the end of the collection be triggered by the end of the rotation of the steering unit 110 correspondingly. Therefore, the controller 150 determines that the steering unit 110 has finished rotating according to the following termination condition. When the rotation is completed, the process proceeds to step S206, and when the rotation is continued, the process returns to step S203.

(Figure 2: Step S205: Basic idea of collection end condition)
When the driver turns the steering wheel, it is assumed that the vehicle 100 will be turned in one direction and the steering wheel will be turned back when the vehicle 100 turns in the desired direction. A series of operations from turning this steering wheel in a certain direction to returning to the initial position is assumed to be one steering operation, and it is in principle to collect sensitivity data for each one steering operation. The start of the steering operation can be determined by step S202. The end of the steering operation is determined according to any of the following conditions.

(FIG. 2: Step S205: Collection end condition 1)
When the steering operation starts, the current command value for rotating the motor for driving the electric power steering device starts to change. It is assumed that the current command value also changes with time along with the steering operation, and returns to near the value at the start of the steering operation when the steering operation is finished. Therefore, when the current command value to the motor starts to change, when it returns to the value at the start of the change again, it is considered that the steering operation has ended, and the sensitive data collection is ended.

(FIG. 2: Step S205: Collection end condition 2)
Similarly, when the steering angle of the steering wheel starts to change and then returns to the value at the start of the change again, it can be considered that the steering operation has ended and the sensitive data collection can be ended. Condition 1 and 2 can also be combined. For example, the sensitive data collection may be terminated when both condition 1 and 2 are satisfied.

(FIG. 2: Steps S203 to S205: Supplement)
In this flowchart, in order to reduce the communication load, only the sensitive data that satisfies the collection condition is transmitted to the evaluation device 200, but the present invention is not limited to this. For example, the evaluation device 200 may acquire all the sensitive data, and discard those that do not meet the above-described collection condition without being evaluated. Alternatively, the evaluation device 200 itself may acquire each data item of the sensitive data and determine itself whether or not the collection condition is met. In this case, it is necessary to connect between the evaluation device 200 and each sensor. In any case, the evaluation device 200 can suppress the load of the evaluation process by targeting only the sensitive data that matches the collection condition.

(FIG. 2: Step S206)
The controller 150 determines whether the ignition of the vehicle 100 is turned off (that is, whether or not to continue the sensitive data collection). If the ignition is in the ON state, the process returns to step S103 to continue collecting sensitive data. If the ignition is off, the present flowchart ends.

  FIG. 3 is a flowchart for explaining a procedure for the analysis unit 230 to analyze the sensitive data. The analysis of the sensitive data referred to here is to find out the data items which the sensitive data have greatly changed in a short time. For example, the analysis unit 230 starts this flowchart when the user of the evaluation apparatus 200 instructs to analyze the sensitive data. Hereinafter, each step of FIG. 3 will be described.

(FIG. 3: Step S301)
The analysis unit 230 calculates the difference between the records for the data item (for example, the torque amount, the steering angle, etc.) of the sensitive data stored in the storage unit 250. That is, the amount of change of the data item is calculated from the previous acquisition timing of the data item.

(FIG. 3: Step S302)
The analysis unit 230 compares the difference obtained in step S301 with a predetermined threshold. If the difference is larger, the process proceeds to step S303. If not, the process returns to step S301 to similarly calculate the difference for the next data item.

(FIG. 3: Step S302: Supplement)
When the data item of the sensitive data changes rapidly, it is considered that the change has a large influence on the steering feeling. Therefore, in this step, it was decided to find out such data items. As the threshold used in this step, an appropriate value is set in advance for each data item. The same applies to the threshold used in step S304 described later.

(FIG. 3: Step S303)
The analysis unit 230 pairs the value of the data item determined to exceed the threshold in step S302 and the difference obtained in step S301, and gives identification information such as the record number of the original sensitive data. Are stored in the storage unit 250 as analysis result data. This process is referred to herein as a variable interval alarm recording.

(FIG. 3: Step S304)
The analysis unit 230 marks all other data items collected at the same timing (that is, in the same record) as the data items recorded with the fluctuation interval alarm as related data items, and steps S301 to S302 for the related data items. Similarly, the difference from the previous acquisition timing is compared with a predetermined threshold.

(FIG. 3: Step S305)
The analysis unit 230 pairs the value of the related data item determined to have exceeded the threshold value in step S304 and the obtained difference, and records them in the same record as the analysis result data stored in the storage unit 250 in step S303. . This process is referred to herein as a related data alarm record.

(FIG. 3: Step S306)
The analysis unit 230 confirms whether or not the above steps have been completed for all the records of the sensitive data. If completed, the flowchart ends. If not completed, the process returns to step S301 to similarly process the next record.

  FIG. 4 is a flowchart illustrating a procedure for the evaluation unit 240 to evaluate the analysis result data. The evaluation referred to here is whether the temporal change of the data item related to the fluctuation interval alarm record and the related data alarm record extracted by the analysis unit 230 is temporary or continuous. It is to judge the For example, when the user of the evaluation apparatus 200 instructs the evaluation unit 240 to evaluate the analysis result data, the evaluation unit 240 starts this flowchart. Hereinafter, each step of FIG. 4 will be described.

(FIG. 4: Step S401)
The evaluation unit 240 reads the analysis result data stored in the storage unit 250. If there is no analysis result data (i.e., neither the fluctuation interval alarm record nor the related data alarm record is implemented in FIG. 3), this flowchart is ended.

(FIG. 4: Step S402)
The evaluation unit 240 selects the data item stored in the storage unit 250 by the fluctuation interval alarm recording in step S303 of FIG. 3 as an evaluation target. The data items to be evaluated can be specified by the user of the evaluation apparatus 200 via the UI unit 210, for example, or all data items held in the analysis result data may be sequentially evaluated.

(FIG. 4: Step S403)
The evaluation unit 240 reads, for the data item selected in step S402, another data item recorded as related data in step S305 in FIG. This step can be skipped if the related data item does not exist.

(FIG. 4: Step S404)
The evaluation unit 240 continuously checks whether the records exceeding the threshold value are continuous for each of the data item selected in step S402 and the related data item acquired in step S403. Determine whether it is occurring or only instantaneous. For example, for a certain data item or its related data item, if records exceeding the threshold value continue for a predetermined number of times or more, it is considered that the data item is continuously and largely fluctuated. The evaluation unit 240 adds a mark indicating that to the analysis result data, or newly creates data describing the same contents, for the data item in which the threshold value excess is continued or its continued part. By doing this, evaluation result data is created and stored in the storage unit 250.

(FIG. 4: Step S405)
The evaluation unit 240 confirms whether the evaluation has been completed for all the data items to be evaluated. If completed, the present flowchart is ended, and if not completed, the process returns to step S403 to evaluate similarly.

  FIG. 5 is a conceptual diagram illustrating a process in which the evaluation unit 240 evaluates the analysis result data. The analysis result data includes a plurality of data items as shown in FIG. 5 and is configured as one record for each acquisition timing. The record number corresponds to the acquisition timing of the sensitive data.

  Record 3 in FIG. 5 is extracted together with the related data (torque amount and steering angle) because the current command value exceeds the predetermined threshold value. The current command values in records 4 and 6 do not exceed the threshold value. Such data items are not important when evaluating the steering feeling because the data item is only momentarily large in change due to some cause and the influence on the steering feeling is considered to be small.

  Records 4 to 6 in FIG. 5 are extracted together with related data (current command value in record 5 and torque amount in record 6) because the steering angle exceeds the predetermined threshold value. The steering angle continuously exceeds the threshold over records 3-6. Thus, the data item that continuously exceeds the threshold value along the time axis seems to have a large influence on the steering operation feeling. Thus, the evaluation unit 240 creates a pickup table by picking up data items that continuously exceed the threshold in this manner, and presents it to the user via the display unit 280.

  As a display format of the pickup table, for example, a graph can be used in which time (corresponding to the acquisition timing of the sensitive data) is taken on the horizontal axis and the value of each data item is taken on the vertical axis. For example, the evaluation unit 240 displays the values of the steering angles illustrated in FIG. 5 as a graph in time series, and marks the parts exceeding the threshold with different colors, etc. so that the user can easily grasp the abnormal parts. Do. Furthermore, the difference from the threshold value described in the analysis result data can be displayed in the vicinity of the plot location, for example. Thereby, the user can easily determine which time point is a problem on the graph and whether or not the problem continues.

  Furthermore, the evaluation unit 240 can also display a graph of the change over time of the related data item. For example, the torque amount and the current command value can be written together with the graph display of the steering angle in FIG. Thus, the user can easily grasp the correlation between the sensitive data items. For example, when the steering angle is marked, it is possible to visually grasp the correlation such that the current command value also tends to be marked. Since it is the current command value for the motor that has the largest influence on the steering feeling of the electric power steering device, it is possible to easily identify the data item that has an influence on it by writing each data item together. Contributing to the improvement of steering feeling.

<Summary of the Invention>
The evaluation device 200 according to the present invention collects only the corresponding sensitive data from the start to the end of the series of handle operations. This enables efficient analysis and evaluation of sensitive data. In addition, it is also possible to suppress the communication load and the like for collecting the sensitive data.

  The evaluation device 200 according to the present invention digitizes the sensitive data, extracts a portion with a large amount of fluctuation, and visually displays the fluctuation. As a result, even a person who is not necessarily familiar with the evaluation of the driving operation or the steering operation feeling can easily evaluate the steering operation feeling represented by the sensitive data.

<About the modification of the present invention>
Each functional unit included in the evaluation apparatus 200 can be implemented by hardware such as a circuit device in which the function is implemented, or an arithmetic unit such as a CPU (Central Processing Unit) executes software in which an equivalent function is implemented. It can also be implemented by

  The contents displayed on the display unit 280 may be customized by the user by instructing via the UI unit 210. For example, it is possible to customize items such as the range of the vertical axis / horizontal axis, the data item to be displayed, the display color of the abnormal part, etc., but it is not limited thereto.

  The communication means for transmitting the sensitive data from the communication control unit 160 to the communication control unit 260 in step S204 may be wired or wireless. There are many sensitive data representing the feeling of steering operation that occur instantaneously, so it is considered preferable to use a wired connection in consideration of the possibility of losing data due to the disconnection of the communication line, but is limited to this. It is not a thing. In the case of wired connection, for example, it is possible to mount the evaluation device 200 in the vehicle 100 and transmit and receive the sensitive data using CAN often used in the vehicle network.

  In the above description, the conditions for ending the collection of sensitive data have been described. For example, when the free capacity of the storage unit 250 reaches the limit, the collection should be terminated under conditions different from the originally scheduled termination conditions. Is also conceivable. For example, (a) when a predetermined time has elapsed since the collection start, (b) when the size of the sensitive data stored in the storage unit 250 reaches a predetermined threshold, (c) when both of them are satisfied, Conditions such as can be considered.

  100: Vehicle, 110: Steering unit, 120: Drive unit, 130: Brake unit, 140: Various sensors, 150: Controller, 160: Communication control unit, 200: Evaluation device, 210: UI unit, 220: Control unit, 230 : Analysis unit, 240: evaluation unit, 250: storage unit, 260: communication control unit, 270: display control unit, 280: display unit.

Claims (6)

A steering operation feeling evaluation device for evaluating a steering operation feeling of an electric power steering device provided in a vehicle,
Sensitive data acquisition that acquires torque amount data representing a steering force applied to a steering wheel included in the vehicle and steering angle data representing a steering angle of the steering wheel as data items of sensitive data representing the steering operation feeling. Department,
A storage device for storing the sensitive data acquired by the sensitive data acquisition unit;
Equipped with
The sensitive data acquisition unit starts acquiring the sensitive data in response to the fact that the steering force has started to change or the steering angle has started to change.
The sensitive data acquisition unit acquires the sensitive data when the steering force starts to change or the steering angle starts to change even when the vehicle speed is 0 km / h. start,
The steering operation feeling evaluation apparatus further comprises an evaluation unit for quantitatively evaluating the sensitive data,
The sensitive data acquisition unit repeatedly acquires the sensitive data and stores the sensitive data in the storage device as one sensitive data record for each acquisition.
The evaluation unit checks whether or not the amount of change over time between the sensitive data records exceeds a predetermined threshold for all the data items included in the sensitive data record. Mark as data item ,
The sensitive data acquisition unit stops acquiring the sensitive data when the size of the sensitive data stored in the storage device reaches a predetermined size. apparatus. The sensitive data acquisition unit further acquires, as the sensitive data, a current command value for a motor that drives the electric power steering apparatus,
The sensitive data acquisition unit, after starting to acquire the sensitive data, when the current command value has changed from the value at the start time at which the sensitive data has started to be acquired and returned to the value at the start time, The steering operation feeling evaluation apparatus according to claim 1, wherein acquisition of the sensitive data is stopped. The sensitive data acquisition unit, after starting to acquire the sensitive data, when the steering angle changes from the value at the start time when the sensitive data starts to be acquired and returns to the value at the start time, The steering operation feeling evaluation apparatus according to claim 1, wherein acquisition of the sensitivity data is stopped. The sensitive data acquisition unit, said sensitive data at the time of the lapse of time specified in advance from starting to get, the sensitive data steering operation feeling evaluation apparatus according to claim 1, wherein the stop to get a . The evaluation unit aligns the sensitive data records in time series;
The evaluation unit marks the fact that, for each of the evaluation target data items of the aligned sensitive data records, the number of times exceeding the predetermined threshold along the time series is a predetermined number or more. The steering operation feeling evaluation device according to claim 1, wherein the steering operation feeling evaluation device is stored in the storage device. The sensitive data acquisition unit further includes, as a data item of the sensitive data,
Operation parameter of the noise filter applied to the data item,
PWM signal value for controlling an inverter that supplies electric power to a motor that drives the electric power steering device;
Mechanical angle of said handle,
As a result of converting the mechanical angle to an electrical angle,
The steering operation feeling evaluation apparatus according to claim 1, wherein:

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