Control devices, control methods, programs, systems, and steering devices.

Abstract

The present invention provides a control device, control method, program, system, and steering device that can improve the accuracy of determining whether an object being detected is in contact with an object. [Solution] The control device includes an acquisition unit that acquires a detected value of the capacitance of an object, and a determination unit that determines whether the object to be detected is not in contact with the object based on a comparison result obtained by comparing the detected value with a threshold value. The determination unit determines that the object to be detected is not in contact with the object if the detected value drops to a predetermined value or more within a predetermined time, regardless of the comparison result.

Description

Technical Field

[0001] The present invention relates to a control device, a control method, a program, a system, and a steering device.

Background Art

[0002] For example, Patent Document 1 describes a sensor that measures the degree of contact of a detection object with an object and outputs a detection value corresponding to the degree of contact, and a contact determination device that determines whether a driver is in contact with or not in contact with a steering wheel based on the detection value of the sensor and a predetermined reference value.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, the detection value varies according to the temperature change of the object. Therefore, Patent Document 1 describes that the contact determination device corrects the reference value corresponding to the temperature change of the object.

[0005] Next, the correction of the reference value corresponding to the temperature change and the like will be described with reference to FIGS. 1 and 2. Here, since an operation for converting the capacitance measured using a capacitance sensor into a digital value is performed, in the following description, the detection value of the capacitance may sometimes be referred to as the "operation value of the capacitance". Also, the driver's contact with the steering wheel is referred to as "hands-on", and the threshold value for determining hands-on may sometimes be referred to as the "hands-on threshold value". Also, the driver's non-contact with the steering wheel is referred to as "hands-off", and the threshold value for determining hands-off may sometimes be referred to as the "hands-off threshold value".

[0006] FIG. 1 is a diagram showing the relationship between the temperature change and the reference value in Comparative Example 1. FIG. 2 is a diagram showing the relationship between the temperature change and the reference value in Comparative Example 2. The horizontal axis of each of FIGS. 1 and 2 represents time, and the vertical axis represents the calculated value (detected value) of the capacitance. Also, the calculated value is shown by a thick dashed line, and the reference value is shown by a thick solid line in FIGS. 1 and 2. Further, the hands-on threshold and the hands-off threshold are each shown by a thin dashed line in FIGS. 1 and 2. Also, the region below the hands-off threshold is shown by hatching. Note that the hands-on threshold is a numerical value obtained by adding a predetermined value v1 to the reference value. Also, the hands-off threshold is a numerical value obtained by adding a predetermined value v2 (<v1) to the reference value.

[0007] As shown by "AA" indicating the amount of change in the calculated value in FIG. 1, when the calculated value becomes equal to or greater than the hands-on threshold, a hands-on determination is made. Also, as shown by "BB" indicating the amount of change in the calculated value in FIG. 1, the calculated value varies due to the temperature change. Further, as shown by "DD" and "EE" in FIG. 1, the reference value, the hands-off threshold, and the hands-on threshold are corrected in response to the temperature change. As a result, as shown by "CC" indicating the amount of change in the calculated value in FIG. 1, when the calculated value becomes less than the hands-off threshold, a hands-off determination is made. As described above, by correcting the reference value, the hands-off threshold, and the hands-on threshold in response to the temperature change, a hands-on / hands-off determination is made. In the following description, the correction of the reference value, the hands-off threshold, and the hands-on threshold may be referred to as "correction of the reference value and the like".

[0008] On the other hand, when the driver repeatedly grips the steering wheel and the temperature of the steering wheel rises, the reference value and the like are corrected in response to the temperature rise. Specifically, as shown by "FF" indicating the amount of change in the calculated value in FIG. 2, when the temperature rise occurs repeatedly, the hands-off threshold is raised, such as the correction of the reference value shown by "HH" and the correction of the hands-off threshold shown by "GG", and there is a problem that the calculated value becomes less than the hands-off threshold and there is a possibility of being erroneously determined as hands-off even though it is hands-on. Also, the same problem occurs when the driver slowly approaches the steering wheel with a hand.

[0009] The object of the present invention is to provide a control device, control method, program, system, and steering device that can improve the accuracy of determining whether an object to be detected is in contact with an object. [Means for solving the problem]

[0010] To achieve the above objectives, the control device in the present invention is An acquisition unit that acquires the detected capacitance value of an object, A determination unit that determines non-contact of the object to be detected with respect to the object based on a comparison result obtained by comparing the detected value with a threshold value, Equipped with, If the detected value decreases to a predetermined value or more within a predetermined time, the determination unit determines, regardless of the comparison result, that the object being detected is not in contact with the object.

[0011] The control method in the present invention is Obtain the detected capacitance value of the object, Based on the comparison result obtained by comparing the detected value with a threshold value, it is determined whether the object to be detected is not in contact with the object. If the detected value decreases to a predetermined value or more within a predetermined time, it is determined that the object to be detected is not in contact with the object, regardless of the comparison result.

[0012] The program in this invention is to the computer A process for obtaining the detected capacitance value of an object, The process involves determining whether the object to be detected is not in contact with the object based on the comparison result obtained by comparing the detected value with a threshold value, and if the detected value decreases to a predetermined value or more within a predetermined time, it is determined that the object to be detected is not in contact with the object, regardless of the comparison result. This is a program to execute [the command / action].

[0013] The system in this invention is The above control device, A touch sensor for measuring the capacitance, It is equipped with.

[0014] The steering device in the present invention is the above control device, the object, the touch sensor that measures the capacitance, and is provided with the object is a steering wheel.

Effect of the Invention

[0015] According to the present invention, it is possible to improve the non-contact determination accuracy of the detection target with respect to the object.

Brief Description of the Drawings

[0016] [Figure 1] FIG. 1 is a diagram showing the relationship between the temperature change and the reference value in Comparative Example 1. [Figure 2] FIG. 2 is a diagram showing the relationship between the temperature change and the reference value in Comparative Example 2. [Figure 3A] FIG. 3A is a diagram showing the outline of the system in the embodiment of the present invention. [Figure 3B] FIG. 3B is a block diagram functionally representing the control device in the embodiment of the present invention. [Figure 4A] FIG. 4A is a diagram showing the reference value and the like in Comparative Example 3. [Figure 4B] FIG. 4B is a diagram showing the positional relationship between the steering wheel and the hand in Comparative Example 3. [Figure 5A] FIG. 5A is a diagram showing the reference value and the like in Comparative Example 4. [Figure 5B] FIG. 5B is a diagram showing the positional relationship between the steering wheel and the hand in Comparative Example 5. [Figure 6A] FIG. 6A is a diagram showing the reference value and the like in Comparative Example 5. [Figure 6B] FIG. 6B is a diagram showing the positional relationship between the steering wheel and the hand in Comparative Example 5. [Figure 7] FIG. 7 is a diagram showing the follow-up speed of the reference value and the like in Comparative Example 6. [Figure 8A] Figure 8A shows the tracking speed of the reference value in Comparative Example 7. [Figure 8B] Figure 8B shows the positional relationship between the steering wheel and the hands in Comparative Example 7. [Figure 9A] Figure 9A shows the reference values, etc., in Comparative Example 8. [Figure 9B] Figure 9B shows the positional relationship between the steering wheel and the hands in Comparative Example 8. [Figure 10A] Figure 10A shows the reference values, etc., in Comparative Example 9. [Figure 10B] Figure 10B shows the positional relationship between the steering wheel and the hands in Comparative Example 9. [Figure 11A] Figure 11A is a diagram showing reference values, etc., in an embodiment of the present invention. [Figure 11B] Figure 11B shows the positional relationship between the steering wheel and the hand in an embodiment of the present invention. [Figure 12A] Figure 12A is a diagram showing reference values, etc., in an embodiment of the present invention. [Figure 12B] Figure 12B shows the positional relationship between the steering wheel and the hand in an embodiment of the present invention. [Figure 13] Figure 13 is a flowchart showing the correction of reference values, etc., in Comparative Example 10. [Figure 14] Figure 14 is a flowchart showing an example of correction of reference values, etc., in an embodiment of the present invention. [Modes for carrying out the invention]

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 3A is a diagram showing an overview of the system in an embodiment of the present invention.

[0018] As shown in Figure 3A, the system 100 in the embodiment of the present invention includes a touch sensor 200 and a touch sensor ECU (Electronic Control Unit) 300.

[0019] The touch sensor 200 has a pair of electrodes 210 and 220 arranged inside the steering wheel 1 (corresponding to the "object" of the present invention), and measures the capacitance between the pair of electrodes 210 and 220. A heater 2 (heating wire) for warming the steering wheel 1 is also arranged inside the steering wheel 1.

[0020] The power source for the touch sensor ECU 300 is the battery. The touch sensor ECU 300 has a control device 300A that determines whether the driver (corresponding to the "detected object" in this invention) is in contact with the steering wheel 1 based on the capacitance measured by the touch sensor 200, and outputs the determination result to the vehicle body ECU (Electronic Control Unit). In the following description, hands-on may be simply referred to as "on" and sometimes simply written as "On". Similarly, hands-off may be simply referred to as "off" and sometimes simply written as "Off". Furthermore, the operation from hands-off (off) to hands-on (on) may be referred to as "touch". Furthermore, the operation from hands-on (on) to hands-off (off) may be referred to as "release".

[0021] Furthermore, in the following explanation, "temperature change" simply refers to temperature changes due to changes in usage and changes in the environment. Also, "temperature change due to changes in usage" refers to temperature changes due to contact between the driver (corresponding to the "detected object" in this disclosure) and the steering wheel (corresponding to the "object" in this disclosure) and / or temperature changes due to the operation of a heater located inside the steering wheel. Also, "temperature change due to changes in the environment" refers to temperature changes due to the ambient temperature around the steering wheel.

[0022] Figure 3B is a block diagram functionally representing the control device in the embodiment of the present invention. As shown in Figure 3B, the control device 300A includes a control unit 310 and a storage unit 320. Further, the control device 300A includes interfaces such as an AD (Analog-to-Digital) converter, a DA (Digital-to-Analog) converter, an I / O (Input / Output) port, and a CAN (Controller Area Network) as interfaces.

[0023] The storage unit 320 is a ROM (Read Only Memory) that stores the program of the computer that realizes the control device 300A and a RAM (Random Access Memory) that serves as the working area of the control device 300A. Note that the ROM may be a flash memory that stores an OS (Operating System), an application program, and various information referred to during the execution of the application program, or a storage device such as an HDD (Hard Disk Drive) or an SSD (Solid State Drive).

[0024] The storage unit 320 stores a reference value, a hands-on threshold value, and a hands-off threshold value. The reference value is a numerical value set corresponding to the temperature of the steering wheel 1. The hands-on threshold value is a numerical value obtained by adding a predetermined value v1 to the reference value, and when the calculated value (detection value) of the capacitance is greater than or equal to the hands-on threshold value, it is a numerical value for which a hands-on determination is made. The hands-off threshold value is a numerical value obtained by adding a predetermined value v2 (<v1) to the reference value, and when the calculated value of the capacitance is less than the hands-off threshold value, it is a numerical value for which a hands-off determination is made.

[0025] The control unit 310 is a processor such as the CPU (Central Processing Unit) of the control device 300A, and functions as an arithmetic unit 311, an acquisition unit 312, a determination unit 313, and a correction unit 314 by executing the program stored in the storage unit 320.

[0026] Note that FIG. 3B shows an example where the control device 300A is composed of a single device. However, the control device 300A may be realized by computing resources such as a plurality of processors and memories, for example. In this case, each part constituting the control unit 310 is realized by executing programs of a plurality of different processors.

[0027] The arithmetic unit 311 outputs the increase amount of the value measured by the touch sensor 200 as a count value based on the measured value. Hereinafter, the capacitance arithmetic value may be simply referred to as "arithmetic value", "detection value", or "count value".

[0028] The acquisition unit 312 acquires the arithmetic value from the arithmetic unit 311.

[0029] The determination unit 313 performs a hands-on determination based on the comparison result of comparing the arithmetic value with the hands-on threshold value. The determination unit 313 performs a hands-off determination based on the comparison result of comparing the arithmetic value with the hands-off threshold value. As described above, the hands-on threshold value is a numerical value obtained by adding a predetermined value v1 to the reference value. The hands-off threshold value is a numerical value obtained by adding a predetermined value v2 (<v1) to the reference value.

[0030] Next, as Comparative Example 3, the case where the reference value is fixed will be described with reference to FIGS. 4A and 4B. FIG. 4A is a diagram showing the reference value and the like in Comparative Example 3. FIG. 4B is a diagram showing the positional relationship between the steering wheel and the hand in Comparative Example 3. The horizontal axis in FIG. 4A represents time, and the vertical axis represents the arithmetic value of capacitance. In FIG. 4A, the arithmetic value is shown by a thick dashed line, and the reference value is shown by a thick solid line. In FIG. 4A, the hands-on threshold value and the hands-off threshold value are each shown by a thin dashed line. The region below the hands-off threshold value is shown by hatching.

[0031] As shown in Figure 4A with "BBB" and "MM," the calculated value fluctuates (increases) with temperature changes. On the other hand, the reference value, hands-off threshold, and hands-on threshold are fixed and not corrected in response to temperature changes (no reference value correction). In this way, when the reference value is not corrected while the calculated value fluctuates (increases), as shown in Figure 4B, a hands-on judgment is made even though it is hands-off (On false detection). In other words, when the reference value is fixed and not corrected in response to temperature changes, there is a risk of On false detection.

[0032] Next, we will explain the case where the reference value is corrected as Comparative Example 4, with reference to Figures 5A and 5B. Figure 5A is a diagram showing the reference value, etc., in Comparative Example 4. Figure 5B is a diagram showing the positional relationship between the steering wheel and the hands in Comparative Example 4. In Figure 5A, the horizontal axis shows time, and the vertical axis shows the calculated value of capacitance. In addition, in Figure 5A, the calculated value is shown with a thick dashed line, and the reference value is shown with a thick solid line. Also in Figure 5A, the hands-on threshold and the hands-off threshold are shown with thin dashed lines. The area below the hands-off threshold is shown with hatching.

[0033] The calculated value fluctuates (rises and falls) with temperature changes, as shown in Figure 5A as "BBB," "CCC," and "DD." The reference value is corrected in response to temperature changes, as shown in Figure 5A as "EE" (reference value correction applied). In this way, as the reference value and other values ​​are corrected, the calculated value fluctuates (rises), and as shown in Figure 5B, if hands-off is indicated, the determination unit 313 can correctly determine hands-off based on the result of comparing the calculated value with the hands-off threshold (by determining that the calculated value is less than the hands-off threshold). In other words, by making the reference value follow the temperature changes, correct hands-off determination can be made.

[0034] Next, as Comparative Example 5, the case where the reference value is fixed during hands-on use will be explained with reference to Figures 6A and 6B. Figure 6A shows the reference value, etc., in Comparative Example 5. Figure 6B shows the positional relationship between the steering wheel and the hands in Comparative Example 5. In Figure 6A, the horizontal axis shows time, and the vertical axis shows the calculated capacitance value. In Figure 6A, the calculated value is shown with a thick dashed line, and the reference value is shown with a thick solid line. In addition, in Figure 6A, the hands-on threshold and the hands-off threshold are shown with thin dashed lines. The area below the hands-off threshold is shown with hatching.

[0035] As shown in Figure 6A, labeled "AA" and "BB," the calculated value fluctuates (increases) due to hand contact with the steering wheel. On the other hand, the reference value, etc., is fixed and not corrected for temperature changes (no reference value correction). Furthermore, as shown in Figure 6A, labeled "CC" and "MM," the calculated value fluctuates (decreases) due to the release of the hand from the steering wheel. In this way, when the reference value, etc., is not corrected, while the calculated value fluctuates (decreases) due to release, the calculated value does not fall below the hands-off threshold. Therefore, as shown in Figure 6B, hands-on detection occurs even when hands-off. In other words, if the reference value is fixed during hands-on operation, there is a risk of hands-on false detection.

[0036] Next, as Comparative Example 6, the tracking speed of the reference value will be explained with reference to Figure 7. Figure 7 is a diagram showing the tracking speed of the reference value in Comparative Example 6. In Figure 7, the horizontal axis shows time, and the vertical axis shows the calculated capacitance value. In Figure 7, the calculated value is shown with a thick dashed line, and the reference value is shown with a thick solid line. In addition, in Figure 7, the hands-on threshold and the hands-off threshold are shown with thin dashed lines. The region below the hands-off threshold is shown with hatching.

[0037] As shown in Figure 7, the calculated value fluctuates (decreases) slowly due to the slow release of the hands from the steering wheel. The reference value is not fixed, as shown in Figure 7, as indicated by "PP," but is corrected to follow the slow fluctuation (decreasing) of the calculated value (reference value correction applied). In this way, when the reference value is corrected to follow the calculated value, the calculated value does not fall below the hands-off threshold, and therefore, as shown in Figure 7, a hands-on determination is made (on-fixed). In other words, even when the reference value is corrected to follow the fluctuation of the calculated value, there is a risk of on-fixation if the tracking speed of the reference value is slow.

[0038] Next, as Comparative Example 7, the tracking speed of the reference value will be explained with reference to Figures 8A and 8B. Figure 8A is a diagram showing the tracking speed of the reference value in Comparative Example 7. Figure 8B is a diagram showing the positional relationship between the steering wheel and the hands in Comparative Example 7. In Figure 8A, the horizontal axis shows time, and the vertical axis shows the calculated value of capacitance. In addition, in Figure 8A, the calculated value is shown with a thick dashed line, and the reference value is shown with a thick solid line. In addition, in Figure 8A, the hands-on threshold and the hands-off threshold are shown with thin dashed lines. The area below the hands-off threshold is shown with hatching.

[0039] The reference value shown in Figure 8A, like the reference value shown in Figure 7, is corrected to follow the fluctuations in the calculated value. However, while the amount of tracking of the reference value shown in Figure 7 is the same as the amount of fluctuation in the calculated value, the amount of tracking of the reference value shown in Figure 8A is less than the amount of fluctuation in the calculated value (the tracking speed of the reference value shown as "EEE" in Figure 8A is lower than the fluctuation speed of the calculated value shown as "BB"). As a result, when the calculated value fluctuates (decreases) due to the release of the hands from the steering wheel, as shown as "DD" in Figure 8A, the calculated value falls below the hands-off threshold, making it possible to correctly determine hands-off status (Off determination). In other words, as shown in Figures 8A and 8B, by making the amount of tracking of the reference value less than the amount of fluctuation in the calculated value, an Off determination can be made correctly.

[0040] Next, as comparative examples 8 and 9, the reference points are not fixed and are corrected, but despite being hands-on, a hands-off judgment is made (fixed to hands-off), and these cases will be explained with reference to Figures 9A to 10B. Figure 9A shows the reference values ​​etc. in comparative example 8. Figure 9B shows the positional relationship between the steering wheel and the hands in comparative example 8. Figure 10A shows the reference values ​​etc. in comparative example 9. Figure 10B shows the positional relationship between the steering wheel and the hands in comparative example 9. In Figures 9A and 10A, the horizontal axis shows time, and the vertical axis shows the calculated capacitance value. In addition, in Figures 9A and 10A, the calculated values ​​are shown with thick dashed lines, and the reference values ​​are shown with thick solid lines. In addition, in Figures 9A and 10A, the hands-on threshold and the hands-off threshold are shown with thin dashed lines, respectively. In addition, the area below the hands-off threshold is shown with hatching.

[0041] The calculated value fluctuates (increases) due to hand touch on the steering wheel, as indicated by "AA" in Figure 9A. Furthermore, the calculated value fluctuates (increases) due to temperature changes, as indicated by "BB" in Figure 9A. Additionally, the calculated value fluctuates (decreases) upon release, as indicated by "CC" and "DD" in Figure 9A. Reference values, etc., are also corrected in response to temperature changes even during touch, as indicated by "EE" in Figure 9A (reference value correction applied). While the reference values, etc., are corrected, if the calculated value fluctuates (decreases) due to the release of the hand from the steering wheel, as indicated by "CC" in Figure 9A, the calculated value falls below the hands-off threshold, making it possible to correctly determine hands-off status (Off determination). In other words, by making the reference value, hands-off threshold, and hands-on threshold track temperature changes even during touch, correct Off determination can be achieved, as shown in Figures 9A and 9B.

[0042] On the other hand, Figure 10A shows the fluctuations in calculated values ​​when a person repeatedly grips the steering wheel, which is a slow, repeated touch by a person's hand, indicated by "FF", the rise in the reference value indicated by "HH", and the rise in the hands-off threshold indicated by "GG". For example, if a person grips the steering wheel once, then releases their hand partway, slowly grips it again, and then releases their hand partway again, the system cannot distinguish between the fluctuations in calculated values ​​due to repeated gripping and the fluctuations in calculated values ​​due to temperature rise, causing the reference value to rise as indicated by "HH" in Figure 10A. When the reference value rises and the gripping state enters the hands-off determination area (the area shown in hatching in Figure 10A), and the calculated value falls below the hands-off threshold, a hands-off determination is made (Off lock) even though the person is still hands-on. In other words, even if the reference value is corrected in response to temperature changes during touching, repeated gripping can lead to misjudgments of hands-off status, as shown in Figures 10A and 10B.

[0043] Therefore, in the control device 300A of the present invention, the reference value is not changed during touch, and logic is added to forcibly determine hands-off when the hand is released from the steering wheel in response to a temperature rise during touch. Specifically, the control device 300A has a determination unit 313 that determines hands-off based on the comparison result between the calculated value and the hands-off threshold, and a correction unit 314 that corrects the reference value etc. in response to the temperature change when hands-off is determined. The determination unit 313 determines hands-off regardless of the comparison result between the calculated value and the hands-off threshold if the calculated value falls by a predetermined value or more within a predetermined time. The predetermined time and predetermined value are set based on experimental or simulation results. The set predetermined time and predetermined value are stored in the storage unit 320. For example, the predetermined value is a value corresponding to the amount of change (increase) of the calculated value at the initial touch.

[0044] The processing of the determination unit 313 and the correction unit 314 in the control device 300A will be explained with reference to Figures 11A to 12B. Figures 11A and 12A show reference values, etc., in an embodiment of the present invention. Figures 11B and 12B show the positional relationship between the steering wheel and the hands in an embodiment of the present invention. In Figures 11A and 12A, the horizontal axis shows time, and the vertical axis shows the calculated value of capacitance. In addition, in Figures 11A and 12A, the calculated value is shown with a thick dashed line, and the reference value is shown with a thick solid line. In addition, in Figures 11A and 12A, the hands-on threshold and the hands-off threshold are shown with thin dashed lines. In addition, the region below the hands-off threshold is shown with hatching.

[0045] The calculated value fluctuates (increases) due to hand touch on the steering wheel, as indicated by "AA" in Figure 11A. The calculated value also fluctuates (increases) due to temperature rise, as indicated by "BB" in Figure 11A. Furthermore, the calculated value fluctuates (decreases) due to release, as indicated by "CC" and "DD" in Figure 11A. On the other hand, the correction unit 314 does not correct the reference value, etc., during touch, as indicated by "AA" and "BB" in Figure 11A. During touch, the determination unit 313 makes a hands-on determination based on the comparison result obtained by comparing the calculated value with the hands-on threshold. If the calculated value drops by a predetermined value or more within a predetermined time due to release, as indicated by "CC" in Figure 11A, the determination unit 313 makes a hands-off determination regardless of the comparison result.

[0046] The correction unit 314 corrects the reference value, etc., when a hands-off determination is made (shown as the correction amount "JJ" for the reference value in Figure 11A). As a result, as shown in Figure 11A, the calculated value falls below the hands-off threshold, and a hands-off determination is also made based on the comparison result. In other words, a hands-off determination is forcibly made by the release descent (decrease in the calculated value due to the release), allowing for a correct Off determination as shown in Figures 11A and 11B.

[0047] On the other hand, when the grip is repeated, the calculated value rises to a level exceeding the hands-on threshold, as shown by "AA" in Figure 12A. Also, as shown by "KK" and "LL" in Figure 12A, the calculated value fluctuates (rises and falls) in the area above the hands-off threshold. Therefore, the hands-on judgment is maintained. In this way, even with fluctuations in the calculated value, the hands-on judgment is maintained and the hands-off judgment is not made, so the reference values, etc., are not corrected. In other words, by not changing (not correcting) the reference values, hands-on threshold, and hands-off threshold even with repeated gripping, the On judgment can be correctly made as shown in Figures 12A and 12B.

[0048] Next, the correction of reference values, etc., in Comparative Example 10 will be explained with reference to Figure 13. Figure 13 is a flowchart showing the correction of reference values, etc., in Comparative Example 10. This flowchart starts when the vehicle starts operating, is then repeated at predetermined intervals, and ends when the operation ends.

[0049] First, in step S100, the control unit 310 determines whether or not a hands-off signal is currently being output. If a hands-off signal is being output (step S100: YES), the process proceeds to step S110. If a hands-off signal is not being output (step S100: NO), the process proceeds to step S170.

[0050] In step S110, the control unit 310 determines whether the calculated value is fluctuating due to environmental changes. If the calculated value is fluctuating due to environmental changes (step S110: YES), the process proceeds to step S120. If the calculated value is not fluctuating due to environmental changes (step S110: NO), the process proceeds to step S150.

[0051] In step S120, the correction unit 314 corrects the value to track the reference value using a weighted average calculation.

[0052] Next, in step S130, the control unit 310 determines whether the calculated value decreases and a reset is determined. If a reset is determined (step S130: YES), the process proceeds to step S140. If a reset is not determined (step S130: NO), the process proceeds to step S160.

[0053] In step S140, the correction unit 314 corrects the reset judgment value so that the reference value follows the reset judgment value. After correcting the value to follow the reference value, the process returns to step S100 after a predetermined time. Here, the reset judgment value is a predetermined numerical value.

[0054] In step S150, the correction unit 314 does not change (does not correct) the reference value.

[0055] In step S160, the correction unit 314 does not change (does not correct) the reference value.

[0056] In step S170, the control unit 310 determines that hands-on output is active (hands-on determination).

[0057] Next, in step S180, the control unit 310 determines whether the calculated value has changed due to environmental changes. If the calculated value has changed due to environmental changes (step S180: YES), the process proceeds to step S190. If the calculated value has not changed due to environmental changes (step S180: NO), the process proceeds to step S210.

[0058] In step S190, the correction unit 314 limits the amount of tracking of the reference value during hands-on operation.

[0059] Next, in step S200, the correction unit 314 corrects the value using a weighted average calculation so that it follows the reference value. After the correction unit 314 corrects the value so that it follows the reference value, the process returns to step S100 after a predetermined time.

[0060] In the correction of reference values, etc., in Comparative Example 10 above, even if logic is included in step S180 to determine whether the calculated value is fluctuating due to environmental changes during hands-on use, it is not possible to distinguish between environmental changes and changes in usage patterns (repeated gripping). Therefore, depending on the amount by which the reference value is tracked during hands-on use, there is a risk of misjudging hands-off mode.

[0061] In Comparative Example 10 described above, the correction unit 314 corrects the reference value to track the fluctuations in the calculated value when the calculated value fluctuates due to environmental changes during hands-on operation. In contrast, as described below, in the control device 300A of the embodiment of the present invention, the correction of the reference value is performed only during hands-off output. Therefore, the correction unit 314 of the embodiment of the present invention does not correct the reference value during hands-on operation.

[0062] Next, an example of correction of reference values, etc., in an embodiment of the present invention will be described with reference to Figure 14. Figure 14 is a flowchart showing an example of correction of reference values, etc., in an embodiment of the present invention. This flowchart starts when the vehicle starts operating, is repeated at predetermined intervals thereafter, and ends when the operation ends. Furthermore, each process from step S300 to step S370 in the flowchart showing an example of correction of reference values, etc., in an embodiment of the present invention is the same as each process from step S100 to step S170 in the flowchart showing correction of reference values, etc., in Comparative Example 10. Therefore, the explanation of each process from step S300 to step S370 will be omitted, and the processes from step S380 onwards will be described.

[0063] In step S380, the correction unit 314 does not change (correct) the reference value during the hands-on output.

[0064] Next, in step S390, the control unit 310 determines whether the calculated value decreases by a predetermined value or more within a predetermined time. If the calculated value decreases by a predetermined value or more (step S390: YES), the process proceeds to step S400. If the calculated value does not decrease by a predetermined value or more (step S390: NO), the process proceeds to step S420.

[0065] In step S400, the control unit 310 outputs a hands-off signal to the vehicle ECU.

[0066] Next, in step S410, the correction unit 314 corrects the reference value so that it follows the calculated value. After a predetermined time has elapsed since the correction unit 314 corrected the reference value so that it follows the calculated value, the process returns to step S300.

[0067] In step S420, the correction unit 314 does not change (does not correct) the reference value.

[0068] The control device in this embodiment of the present invention includes an acquisition unit 312 that acquires calculated capacitance values ​​between a pair of electrodes 210 and 220 arranged in the steering wheel 1, and a determination unit 313 that performs a hands-off determination, which is a determination of whether the driver is not in contact with the steering wheel 1, based on a comparison result obtained by comparing the acquired calculated value with a hands-off threshold. The determination unit 313 performs a hands-off determination regardless of the comparison result if the acquired calculated value falls to a predetermined value or more within a predetermined time.

[0069] With the above configuration, the hands-off threshold is not adjusted to follow fluctuations in the calculated value during hands-on practice. Instead, if a predetermined condition (the calculated value decreases to a predetermined value or more within a predetermined time) is met at the time of release, a hands-off determination is forcibly made. This allows for correct hands-off determination even when repeated gripping occurs during hands-on practice, thereby improving the accuracy of hands-off determination.

[0070] Furthermore, the control device in the embodiment of the present invention further includes a correction unit 314 that performs a correction to increase the threshold value in response to the temperature rise after the calculated value has fallen to a predetermined value or more within a predetermined time and a hands-off determination has been forcibly made. This makes it possible to properly correct the threshold value after the hands-off determination, thereby improving the accuracy of subsequent hands-on / hands-off determinations.

[0071] In the control device 300A in the embodiment of the present invention, the predetermined time and predetermined value, which are the conditions for forcibly turning off the device upon release, are set by experimentation or the like. However, the present invention is not limited to this, and these may be adjustable after they have been set. This makes it possible to provide a steering device that can accommodate differences in the surface material of the steering device and the user's grip preferences.

[0072] Furthermore, in the control device 300A of the embodiment of the present invention, in step S410, the correction unit 314 corrects the reference value so that it follows the calculated value. However, the reference value may also be corrected according to the amount of change between the temperature before correction and the temperature at the time of correction. This also makes it possible to correct the reference value after the hands-off determination to an appropriate value.

[0073] Furthermore, in the control device 300A of the present invention, a temperature sensor may be provided to detect the temperature of the steering wheel, and a hands-off determination of the steering wheel may be made based on the detection result from the temperature sensor.

[0074] Furthermore, the above embodiments are merely examples of how the present invention may be implemented, and the technical scope of the present invention should not be limited by them. In other words, the present invention can be implemented in various ways without departing from its gist or its main features. [Industrial applicability]

[0075] This invention is used in steering devices equipped with a control device that requires improved accuracy in determining whether an object is in contact with a detected object. [Explanation of Symbols]

[0076] 100 Systems 200 touch sensors 210 Electrode 220 electrode 300 Touch Sensor ECU 300A control device 310 Control Unit 311 Arithmetic unit 312 Acquisition Department 313 Judgment section 314 Correction Unit 320 Storage section

Claims

1. An acquisition unit that acquires the detected capacitance value of an object, A determination unit that determines non-contact of the object to be detected with respect to the object based on a comparison result obtained by comparing the detected value with a threshold value, Equipped with, The determination unit determines, regardless of the comparison result, that the object being detected is not in contact with the object if the detected value falls to a predetermined value or more within a predetermined time. Control device.

2. The system further includes a correction unit that performs a correction to increase the threshold value in response to a temperature rise after it is determined that the detected value has decreased to a predetermined value or more within a predetermined time and the object being detected is not in contact with the object. The control device according to claim 1.

3. Obtain the detected capacitance value of the object, Based on the comparison result obtained by comparing the detected value with a threshold value, it is determined whether the object to be detected is not in contact with the object. If the detected value decreases to a predetermined value or more within a predetermined time, it is determined that the object to be detected is not in contact with the object, regardless of the comparison result. Control method.

4. to the computer A process for obtaining the detected capacitance value of an object, The process involves determining whether the object to be detected is not in contact with the object based on the comparison result obtained by comparing the detected value with a threshold value, and if the detected value decreases to a predetermined value or more within a predetermined time, it is determined that the object to be detected is not in contact with the object, regardless of the comparison result. A program to execute.

5. The control device according to claim 1, A touch sensor for measuring the capacitance, Equipped with, system.

6. The control device according to claim 1, The aforementioned object and, A touch sensor for measuring the capacitance, Equipped with, The aforementioned object is a steering wheel. Steering system.

Images