Detection device and operating unit

Abstract

To provide a detection device capable of detecting the position of an object with high precision. [Solution] The detection device (100) includes an electrostatic sensor (110) placed on a holding member (10) having a conductor (11) to which a predetermined potential or a predetermined waveform potential is applied; a detection circuit (120) connected to the electrostatic sensor (110) and measuring the capacitance of the electrostatic sensor (110); a positional deviation calculation unit (131) that calculates the positional deviation of the electrostatic sensor (110) relative to the conductor (11) or a value corresponding to the positional deviation based on the output of the detection circuit (120) in a non-proximity state where the object is not in close proximity to the conductor (11); a correction value calculation unit (132) that calculates a correction value corresponding to the positional deviation or value corresponding to the positional deviation calculated by the positional deviation calculation unit (131); and a detection unit (133) that detects the position of the object based on the output of the detection circuit (120) and the correction value calculated by the correction value calculation unit (132).

Description

Technical Field

[0006] , , ,

[0005] , ,

[0001] The present disclosure relates to a detection device and an operation unit.

Background Art

[0002] Conventionally, there is an input device having a plurality of conductive operation knobs, a plurality of electrodes provided in pairs with the plurality of operation knobs and arranged at a predetermined distance so as to face those provided in pairs among the plurality of operation knobs, detection means for detecting a capacitance formed between the operation knobs and the electrodes, and operation determination means for determining an operation performed on the plurality of operation knobs according to the capacitance detected by the detection means (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

[0007] This invention provides a detection device and operating unit capable of detecting the position of an object with high precision. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows an example of the appearance of an operating unit 200 including a detection device 100 of the embodiment. [Figure 2] This figure shows an example of a cross-section obtained by cutting the operating unit 200 with a plane parallel to the XZ plane. [Figure 3] This figure shows the external appearance of the sensor unit 150. [Figure 4] This figure shows an example of a state in which the sensor unit 150 is placed on the metal member 11. [Figure 5] This is a diagram showing an example of the configuration of the sensor sheet 115. [Figure 6A] This diagram illustrates an example of a state in which the eight electrostatic sensors 110 are not misaligned relative to the metal member 11. [Figure 6B] This diagram illustrates an example of misalignment of eight electrostatic sensors 110 relative to a metal member 11. [Figure 6C] This diagram illustrates an example of misalignment of eight electrostatic sensors 110 relative to a metal member 11. [Figure 6D]This diagram illustrates an example of misalignment of eight electrostatic sensors 110 relative to a metal member 11. [Figure 7A] This diagram illustrates an example of a state in which the eight electrostatic sensors 110 are not misaligned relative to the metal member 11. [Figure 7B] This diagram illustrates an example of misalignment of eight electrostatic sensors 110 relative to a metal member 11. [Figure 7C] This diagram illustrates an example of misalignment of eight electrostatic sensors 110 relative to a metal member 11. [Figure 7D] This diagram illustrates an example of misalignment of eight electrostatic sensors 110 relative to a metal member 11. [Figure 8A] This flowchart shows an example of the process performed by the positional deviation calculation unit 131. [Figure 8B] This flowchart shows an example of the process performed by the positional deviation calculation unit 131. [Modes for carrying out the invention]

[0009] The following describes embodiments to which the detection device and operating unit of this disclosure are applied.

[0010] <Embodiment> The following explains the XYZ coordinate system. The directions parallel to the X-axis (X direction), the directions parallel to the Y-axis (Y direction), and the directions parallel to the Z-axis (Z direction) are mutually orthogonal. Plane view refers to viewing from the XY plane. For the sake of explanation, we will use an up-down relationship where the +Z direction side is the top and the -Z direction side is the bottom, but this does not represent a universal up-down relationship. In addition, in the following, the length, width, thickness, etc. of each part may be exaggerated to make the structure easier to understand.

[0011] <Operating unit 200 including detection device 100 of the embodiment> FIG. 1 is a perspective view showing an example of the configuration of an operation unit 200 including a detection device 100 according to an embodiment. FIG. 2 is a diagram showing an example of a cross-section cut along a plane parallel to the XZ plane of the operation unit 200. FIG. 3 is a diagram showing the appearance of a sensor unit 150 provided with the detection device 100. FIG. 4 is a diagram showing an example of a state where the sensor unit 150 is arranged on a metal member 11. The XYZ coordinates are set based on the metal member 11. Since the positional relationship among the sensor unit 150, the metal member 11, and the operation panel 210 when attached to the metal member 11 in a non-displaced state is constant, the XYZ coordinates are set based on the operation panel 210, or it can also be said that they are set based on the sensor unit 150 when attached to the metal member 11 in a non-displaced state. The origin of the coordinates in the XY plane is located at the center of the protruding portion 214 in a plan view and coincides with the center of the sensor unit 150 in a plan view (see FIG. 3) when attached to the metal member 11 in a non-displaced state, which can be rephrased. The origin of the coordinates of the Z axis is located, as an example, at the center in the Z direction of the base 220 of the sensor unit 150 when attached to the metal member 11 in a non-displaced state (see FIG. 7A).

[0012] <Configuration of the operation unit 200> The operation unit 200 includes a sensor unit 150 provided with the detection device 100 and an operation panel 210 (see FIG. 1). The operation panel 210 has a flat portion 213 and a cylindrical protruding portion 214 that an operator operates, and is mounted on a conductive metal core 10. The core 10 has, as an example, a plate-shaped metal member 11. The core 10 is an example of a holding member that holds the metal member 11. The metal member 11 is an example of a conductor. The core 10 is, as an example, a part of a vehicle chassis. The metal member 11 is attached to the core 10 by welding or the like, or is a part thereof. The core 10 and the metal member 11 are covered by the operation panel 210 and are not exposed. The core 10 is grounded and the metal member 11 is also grounded. A potential of a predetermined potential or a predetermined waveform may be applied to the core 10 and the metal member 11 from an electronic device (not shown) of the vehicle. The metal member !1 and the operation panel 11 are attached to the core 10 in a state of being positioned with high precision.

[0013] The operation panel 210 is, for example, the front panel of a vehicle integrally provided with a protruding portion 214 that an operator actually operates. As shown in FIG. 1, it has the protruding portion 214 and the flat portion 213 around it. The protruding portion 214 has a side surface 211 and an upper surface 212. The protruding portion 214 is a cup-shaped member having a cylindrical wall portion (side wall) with the side surface 211 and a disk-shaped wall portion with a circular upper surface 212. The operation panel 210 is, as an example, made of resin. Note that the protruding portion 214 may be integrally formed with the flat portion 213, or may be separately formed and integrally formed by holding one to the other.

[0014] On the protruding portion 214 of the operation panel 210, four operation portions 210A are provided as an example. The four operation portions 210A are provided at 90-degree intervals on the circumference centered on the center of the upper surface 212. An operation portion 210AW is provided on the -X direction side of the center of the upper surface 212, an operation portion 210AE is provided on the +X direction side, an operation portion 210AS is provided on the -Y direction side, and an operation portion 210AN is provided on the +Y direction side, one by one. On the operation portion 210A, a symbol (mark, symbol, character, or number, etc.) representing the function of an electrical component of the vehicle is represented as an example. The symbol may be printed, or may be configured to be illuminated by an LED (Light Emitting Diode) or the like provided on the base 220 inside the operation unit 200, specifically inside the sensor unit 150, and the light is transmitted.

[0015] <Configuration of the sensor unit 150> The sensor unit 150 includes a detection device 100 and a holder 151 that holds the detection device 100. The holder 151 has a first case 151a with one end open and a base 220 that is attached to the opening at the bottom of the first case 151a. The first case 151a has a side surface 151a1 and a top surface 151a2. The first case 151a is a cup-shaped member having a cylindrical wall portion (side wall) with a side surface 151a1 and a disc-shaped wall portion (top wall) with a circular top surface 151a2. The sensor sheet 115 of the detection device 100 is attached to the side surface 151a1, and a through hole corresponding to the operating section 210A is provided on the top surface 151a2, forming a transparent section 152.

[0016] The base 220 (see Figure 2) is a substrate made of insulating resin and is on which the detection circuit 120 (not shown in Figure 2), ECU (Electronic Control Unit) 130 (not shown in Figure 2), temperature sensor 140 (not shown in Figure 2), and the aforementioned LEDs, etc. (not shown in Figure 2) of the detection device 100 are mounted. In this embodiment, the sensor unit 150 is attached to the metal member 11 of the core metal 10 of the vehicle by the base 220 using double-sided tape or adhesive. The sensor unit 150 may also be attached to the metal member 11 of the core metal 10 by the first case 151a.

[0017] <Configuration of detection device 100> The detection device 100 includes an electrostatic sensor 110, a detection circuit 120, and an ECU (Electronic Control Unit) 130, and in this embodiment, it includes a temperature sensor 140. In Figure 4, the detection circuit 120, ECU 130, and temperature sensor 140 are shown in a simplified manner. In this embodiment, the detection circuit 120, ECU 130, and temperature sensor 140 are provided in the sensor unit 150, but they may be provided outside the sensor unit 150. Alternatively, the detection circuit 120 may be provided in the sensor unit 150, and the ECU 130 and temperature sensor 140 may be provided outside the sensor unit 150. Alternatively, the detection circuit 120 and ECU 130 may be provided in the sensor unit 150, and the temperature sensor 140 may be provided outside the sensor unit 150.

[0018] <Electrostatic sensor 110> As shown in Figures 2 and 4, the electrostatic sensor 110 is provided on the outer surface of the cylindrical wall portion having a side surface 151a1. The electrostatic sensor 110 may also be provided on the inner surface of the cylindrical wall portion having a side surface 151a1 (the surface on the back side of the side surface 151a1 of the cylindrical wall portion). As an example, eight electrostatic sensors 110 (which can also be called electrostatic sensor electrodes) are provided, and each electrostatic sensor 110 is made of a metal foil such as copper or aluminum, as an example. Each electrostatic sensor 110 has a shape such as a rectangular metal foil curved along the side surface 151a1, as an example, but it is not limited to a rectangular shape and may be trapezoidal, elliptical, or other shapes. Each electrostatic sensor 110 is connected to the detection circuit 120.

[0019] The eight electrostatic sensors 110 are, for example, arranged in two vertical rows (upper and lower rows), with four electrostatic sensors 110 provided along the circumferential direction of the side surface 151a1 in each row. The lengths of the four electrostatic sensors 110 provided along the circumferential direction in each row are equal to each other in the circumferential direction, and their widths in the vertical direction are equal to each other. That is, the four electrostatic sensors 110 provided along the circumferential direction have equal area and shape to each other. Furthermore, the four electrostatic sensors 110 provided along the circumferential direction are provided at equal intervals in the circumferential direction.

[0020] In each stage, the centers of length in the circumferential direction of two of the four electrostatic sensors 110 arranged along the circumferential direction are, for example, located on the X-axis, and the centers of length in the circumferential direction of the remaining two electrostatic sensors 110 are, for example, located on the Y-axis. Therefore, the two electrostatic sensors 110 positioned in the upper and lower stages at four locations in the circumferential direction have equal area and shape, and their positions in the circumferential direction coincide.

[0021] The electrostatic sensor 110 provided along the side surface 151a1 can be manufactured by attaching a flexible substrate 111 on which eight electrostatic sensors 110 are formed to the side surface 151a1 of the sensor unit 150, as shown in Figure 5 as an example. Figure 5 shows an example of the configuration of the sensor sheet 115. The sensor sheet 115 is realized by a flexible substrate 111, and has a configuration in which eight electrostatic sensors 110 are formed on one surface of the flexible substrate 111. The flexible substrate 111 is, for example, an elongated rectangular shape, and on one surface of the flexible insulating substrate, eight electrostatic sensors 110 of the same area and shape are formed in a 2-row (vertical) and 4-column (horizontal) arrangement at equal intervals vertically and horizontally. Note that in Figures 4 and 5, the wiring patterns and terminal electrodes formed on the flexible substrate 111 for connecting each electrostatic sensor 110 to the detection circuit 120 are omitted from the illustration.

[0022] Furthermore, in the following, the eight electrostatic sensors 110 will be referred to as follows: The -X direction side will be W (West), the +X direction side will be E (East), the -Y direction side will be S (South), the +Y direction side will be N (North), the upper row will be U (Upper), and the lower row will be L (Lower). Under this rule, as shown in Figure 4, the lower electrostatic sensor 110 on the -X direction side will be called WL, and the upper electrostatic sensor 110 on the -X direction side will be called WU. The lower electrostatic sensor 110 on the +X direction side will be called EL, and the upper electrostatic sensor 110 on the +X direction side will be called EU. The lower electrostatic sensor 110 on the -Y direction side will be called SL, and the upper electrostatic sensor 110 on the -Y direction side will be called SU. The lower electrostatic sensor 110 on the +Y direction side will be called NL, and the upper electrostatic sensor 110 on the +Y direction side will be called NU. Figure 5 shows the labels SL, SU, WL, WU, NL, NU, EL, and EU on the eight electrostatic sensors 110 of the sensor sheet 115 before it is attached to the side surface 151a1 of the sensor unit 150.

[0023] <Detection circuit 120> The detection circuit 120 is connected to each electrostatic sensor 110 and detects the capacitance of each electrostatic sensor 110. The detection circuit 120 digitally converts the capacitance of the electrostatic sensors 110 to obtain a value AD corresponding to the capacitance of each electrostatic sensor 110 and outputs it to the ECU 130.

[0024] <ecu130> The ECU 130 includes a position deviation calculation unit 131, a correction value calculation unit 132, a detection unit 133, and a memory 134. The ECU 130 is connected to the detection circuit 120.

[0025] The ECU130 is implemented by a computer including a CPU (Central Processing Unit), RAM (Random Access Memory), ROM (Read Only Memory), input / output interface, and internal bus. The position deviation calculation unit 131, the correction value calculation unit 132, and the detection unit 133 represent the functions of the program executed by the ECU130 as functional blocks. The memory 134 functionally represents the memory of the ECU130.

[0026] <Position deviation calculation unit 131> The positional deviation calculation unit 131 calculates the positional deviation of the electrostatic sensor 110 relative to the metal member 11, or a value corresponding to the positional deviation, based on the output of the detection circuit 120 in a non-proximity state where the object is not in close proximity to the metal member 11. Details of this will be described later.

[0027] <Correction Value Calculation Unit 132> The correction value calculation unit 132 calculates a correction value corresponding to the positional deviation calculated by the positional deviation calculation unit 131, or a value corresponding to the positional deviation. Details of this will be described later.

[0028] <Detection unit 133> The detection unit 133 detects the position of the object relative to the metal member 11 based on the output of the detection circuit 120 and the correction value calculated by the correction value calculation unit 132. Details of this will be described later.

[0029] <Temperature sensor 140> The capacitance value of the electrostatic sensor 110 changes with temperature, but the temperature sensor 140 is used to compensate for the capacitance of the electrostatic sensor 110 due to temperature changes, and is used to detect with higher accuracy whether a fingertip or the like is approaching or touching the operating unit 210A. The temperature sensor 140 is composed of a thermistor. Incidentally, if the output value of the baseline (a value corresponding to the noise floor, set assuming that there are no objects to be detected in the surroundings) is determined by a separately provided reference electrode, the change in the baseline of the electrostatic sensor 110 due to temperature changes and the change in the capacitance value of the reference electrode can be considered equivalent, so it is possible to accurately estimate the baseline of the electrostatic sensor 110 by measuring the capacitance value of the reference electrode. Therefore, even if there is a temperature change, it is possible to accurately determine the change in capacitance value (difference value ΔAD) of the electrostatic sensor 110 due to the proximity of a fingertip or the like. However, when a reference electrode is provided for compensation, the baseline value may shift due to a shift in the mounting position of the reference electrode on the vehicle, etc. If the baseline value is set by the temperature measured by the temperature sensor 140, it is less susceptible to the effects of positional shifts, etc., that would occur if a reference electrode were provided.

[0030] Such an operating unit 200 can be operated by the operator touching one of the four operating sections 210A with their fingertip or the like. The operator's fingertip or the like is an example of an object. The position of the object is detected based on the capacitance of the electrostatic sensor 110.

[0031] Furthermore, since such an operating unit 200 is placed on a metal member 11, the eight electrostatic sensors 110 are affected by parasitic capacitance between them and the metal member 11.

[0032] Incidentally, the parasitic capacitance between the eight electrostatic sensors 110 and the metal member 11 can change depending on the position of the eight electrostatic sensors 110 relative to the metal member 11. Also, when the sensor unit 150 is attached to the metal member 11, a misalignment of the sensor unit 150 relative to the metal member 11 may occur. That is, as mentioned above, the metal member 11 and the operation panel 210 are attached to the core metal 10 in a highly precise positioned state, so if a misalignment occurs when attaching the sensor unit 150 to the metal member 11, a misalignment of the sensor unit 150 relative to the operation panel 210 having four operation sections 210A may occur. Furthermore, when the sensor sheet 115 (see Figure 5), on which the eight electrostatic sensors 110 are formed, is attached to the side surface 151a1 of the sensor unit 150, a misalignment of the sensor sheet 115 relative to the sensor unit 150 may occur. Furthermore, since the detection of approach to or touch of the four operating units 210A is performed by the output of the electrostatic sensor 110, if there is a misalignment between the electrostatic sensor 110 and the four operating units 210A, the detection accuracy of approach to or touch of the four operating units 210A may decrease.

[0033] <Specific examples of misalignment> Figures 6A to 6D and 7A to 7D illustrate an example of positional misalignment of the eight electrostatic sensors 110 relative to the metal member 11, assuming that there is almost no misalignment of the electrostatic sensors 110 relative to the sensor unit 150, and that misalignment occurs when the sensor unit 150 is attached to the metal member 11.

[0034] <Figures 6A to 6D> Figures 6A to 6D illustrate a scenario where horizontal misalignment occurs when mounting the metal member 11 and the sensor unit 150. The positioning mechanism between the sensor unit 150 and the metal member 11 minimizes Z-axis misalignment, but horizontal misalignment is possible. For example, this scenario is when the base 220 is mounted on the metal member 11 without tilting in the Z-axis direction.

[0035] Figures 6A to 6D show the positional relationship between the metal member 11 and the electrostatic sensors 110 in a plan view from the +Z direction. Figure 6A shows the state where there is no positional misalignment of the eight electrostatic sensors 110 relative to the metal member 11. Figures 6B to 6D show the state where there is positional misalignment of the eight electrostatic sensors 110 relative to the metal member 11 in a plan view. In Figures 6A to 6D, the eight electrostatic sensors 110 are not tilted with respect to the Z axis, and the upper and lower electrostatic sensors 110 overlap, thus showing the positional relationship between the metal member 11 and the lower electrostatic sensors 110 (WL, EL, SL, WL). Note that in Figures 6A to 6D, the XYZ coordinates are shown offset from the eight electrostatic sensors 110.

[0036] In Figure 6A, since there is no misalignment of the eight electrostatic sensors 110 relative to the metal member 11, the eight electrostatic sensors 110 are evenly positioned in the X and Y directions relative to the metal member 11. The size relationship between the metal member 11 and the eight electrostatic sensors 110 in the absence of misalignment is shown in Figure 6A as an example.

[0037] In Figure 6B, the positions of the eight electrostatic sensors 110 are offset in the +X direction relative to the metal member 11, and the electrostatic sensor EL protrudes from the metal member 11 in the +X direction.

[0038] In Figure 6C, the positions of the eight electrostatic sensors 110 are shifted in the +Y direction relative to the metal member 11, and the electrostatic sensor NL protrudes from the metal member 11 in the +Y direction.

[0039] In Figure 6D, the positions of the eight electrostatic sensors 110 are rotated clockwise around the Z-axis and shifted relative to the metal member 11. Although the eight electrostatic sensors 110 are located inside the outer edge of the metal member 11 in a plan view, their positions are shifted relative to the four operating parts 210A (see Figure 1).

[0040] <Figures 7A to 7D> Figures 7A to 7D show the electrostatic sensor 110 and metal member 11, as well as the sensor sheet 115 and base 220. Figures 7B to 7D assume a case where misalignment in the Z direction occurs when mounting the metal member 11 and the sensor unit 150. The positioning mechanism between the sensor unit 150 and the metal member 11 minimizes horizontal misalignment, while misalignment in the Z direction occurs. For example, this would be the case when the centers of the metal member 11 and the base 220 are aligned and mounted. In Figure 7B, a guide is provided along the X-axis; in Figure 7C, a guide is provided along the Y-axis; and in Figure 7D, a guide is provided at the center of the holder 151 in the Z-axis direction.

[0041] Figure 7A shows a state in which there is no misalignment of the sensor unit 150 relative to the metal member 11, and no misalignment of the eight electrostatic sensors 110.

[0042] Figure 7B shows the state in the YZ plane view from the -X side, where the rotation of the sensor unit 150 around the X axis causes a positional displacement Rx of the eight electrostatic sensors 110 relative to the metal member 11.

[0043] Figure 7C shows the state in the XZ plane view from the -Y side, where the rotation of the sensor unit 150 around the Y axis causes a positional misalignment Ry of the eight electrostatic sensors 110 relative to the metal member 11.

[0044] Figure 7D shows a state in the YZ plane view from the -X side, where the sensor unit 150 is shifted in the +Z direction, resulting in a positional misalignment Z of the eight electrostatic sensors 110 relative to the metal member 11.

[0045] As explained using Figures 6B to 6D and Figures 7B to 7D, for example, if the position in which the sensor unit 150 is attached to the core metal 10 is misaligned, the positions of the eight electrostatic sensors 110 may be misaligned with respect to the metal member 11 in a plan view, as shown in Figures 6B to 6D.

[0046] Furthermore, for example, if the position where the sensor unit 150 is attached to the core metal 10 is shifted in the Z direction, a positional misalignment Rx or Ry, or a positional misalignment Z, may occur between the eight electrostatic sensors 110 and the metal member 11, as shown in Figures 7B to 7D.

[0047] If there is a misalignment between the eight electrostatic sensors 110 and the metal member 11, the parasitic capacitance will change, which may prevent the accurate detection of the object's position based on the capacitance of the eight electrostatic sensors 110.

[0048] Therefore, the detection device 100 detects the positional deviation of the eight electrostatic sensors 110 relative to the reference position and calculates a correction value to suppress the effect of the positional deviation. Then, based on the output of the detection circuit 120 and the correction value, it detects the position of the object.

[0049] The operation unit 200 determines, based on the position of the object detected by the detection device 100, which of the four operation units 210A has been approached or touched.

[0050] <Flowchart> The following flowcharts show the flowcharts executed by the positional misalignment calculation unit 131 for the cases where the positional misalignment shown in Figure 6 and the positional misalignment shown in Figure 7 are assumed, and these are performed after the capacitance of each electrostatic sensor 110 is acquired by the detection circuit 120.

[0051] The flowchart executed by the positional deviation calculation unit 131 is performed after the sensor unit 150 is attached to the metal member 11 provided on each actual vehicle, and is performed when there are no objects to be detected, such as fingertips, in the vicinity. Specifically, it is performed before the vehicle is shipped from the factory, or each time the user uses it. As one way to determine when there are no objects to be detected in the vicinity when the user is using it, the condition that the operation unit 200 is not being operated may be used to make this determination.

[0052] The flowchart in Figure 8A will be explained below.

[0053] Figure 8A is a flowchart showing an example of the process executed by the misalignment calculation unit 131 when any of the misalignments shown in Figure 6 are expected. Note that if the mounting mechanism only causes a predetermined misalignment, for example, a misalignment in the Y direction, when mounting the metal member 11 and the sensor unit 150, then only the misalignment in the Y direction shown in steps S1 to S6 may be calculated.

[0054] In the following, the positions of the eight electrostatic sensors 110 when there is no misalignment will be referred to as the reference positions. The positions of the eight electrostatic sensors 110 shown in Figure 6A are the reference positions.

[0055] First, the positional deviation calculation unit 131 calculates the Y-direction positional deviation of the eight electrostatic sensors 110 relative to the reference position by processing steps S1 to S6. Next, the positional deviation calculation unit 131 calculates the X-direction positional deviation of the eight electrostatic sensors 110 relative to the reference position by processing steps S11 to S16. Furthermore, the positional deviation calculation unit 131 calculates the positional deviation of the eight electrostatic sensors 110 around the Z-axis relative to the reference position by processing steps S21 to S26.

[0056] Furthermore, the positional displacement calculation unit 131 uses the difference value ΔAD and the fluctuation value dAD for the eight electrostatic sensors 110 when calculating the positional displacement.

[0057] The difference value ΔAD is obtained by subtracting the baseline (a value equivalent to the noise floor, set assuming there are no objects to be detected in the surrounding area) from the digital capacitance value AD.

[0058] The variation value dAD is obtained by subtracting the difference value ΔAD at the reference position from the actual difference value ΔAD. In other words, the variation value dAD represents the amount of variation in the difference value ΔAD due to the deviation of each electrostatic sensor 110 from the reference position. The actual difference value ΔAD is obtained from the digital value AD of capacitance detected by the detection circuit 120 after the sensor unit 150 has been attached to the metal member 11 provided on each actual vehicle, etc., and there are no objects to be detected in the surrounding area. The difference value ΔAD at the reference position is determined in advance from the digital value AD of capacitance measured by the detection circuit 120 after the sensor unit 150 has been attached to the metal member 11 without any positional deviation, and there are no objects to be detected in the surrounding area, or it is determined in advance by calculation.

[0059] Furthermore, the difference value ΔAD and the variation value dAD will be used with the same meaning in the explanation of the flowchart in Figure 8B and other documents described later.

[0060] The fluctuation value dAD may also be obtained by subtracting the digital value AD at the reference position from the actual digital value AD. That is, the fluctuation value dAD may be obtained by subtracting the digital value AD at the reference position of the capacitance measured by the detection circuit 120 after the sensor unit 150 has been attached to the metal member 11 provided on each actual vehicle, etc., and there are no objects to be detected in the vicinity, from the actual digital value AD of the capacitance detected by the detection circuit 120.

[0061] Alternatively, a digital value AD may be used instead of the difference value ΔAD.

[0062] In the flowchart shown in Figure 8A, the variable values ​​dAD are dAD[NL], dAD[SL], dAD[EL], and dAD[WL].

[0063] The variation value dAD[NL] is obtained by subtracting the difference value ΔAD[NL] for the electrostatic sensor NL at the reference position from the actual difference value ΔAD[NL] for the electrostatic sensor NL.

[0064] The variation value dAD[SL] is obtained by subtracting the difference value ΔAD[SL] for the electrostatic sensor SL at the reference position from the actual difference value ΔAD[SL] for the electrostatic sensor SL.

[0065] The fluctuation value dAD[EL] is obtained by subtracting the difference value ΔAD[EL] for the electrostatic sensor EL at the reference position from the actual difference value ΔAD[EL] for the electrostatic sensor EL.

[0066] The variation value dAD[WL] is obtained by subtracting the difference value ΔAD[WL] for the electrostatic sensor WL at the reference position from the actual difference value ΔAD[WL] for the electrostatic sensor WL.

[0067] The difference values ​​ΔAD[NL] for electrostatic sensor NL at the reference position, ΔAD[SL] for electrostatic sensor SL at the reference position, ΔAD[EL] for electrostatic sensor EL at the reference position, and ΔAD[WL] for electrostatic sensor WL at the reference position can be obtained in advance and stored in memory 134.

[0068] Furthermore, the following flowchart uses thresholds TH[NLY], TH[SLY], TH[ELX], TH[WLX], and TH[RZ]. Thresholds TH[NLY] and TH[SLY] are used to determine if there is a deviation in the Y direction of the fluctuation values ​​dAD[NL] and dAD[SL], respectively. Thresholds TH[ELX] and TH[WLX] are used to determine if there is a deviation in the X direction of the fluctuation values ​​dAD[EL] and dAD[WL], respectively. Threshold TH[RZ] is used to determine if there is a deviation in the rotation direction of the fluctuation values ​​dAD[NL], dAD[SL], TH[ELX], and TH[WLX]. Appropriate values ​​for thresholds TH[NLY], TH[SLY], TH[ELX], TH[WLX], and TH[RZ] can be determined in advance and stored in memory 134. Note that the thresholds TH[NLY], TH[SLY], TH[ELX], TH[WLX], and TH[RZ] are set to positive values.

[0069] <Steps S1-S6> Steps S1 to S6 determine whether there is a positional displacement in the Y direction as shown in Figure 6C. In general, steps S1 and S2 determine whether there is a displacement in the +Y direction, and steps S4 and S5 determine whether there is a displacement in the -Y direction. A detailed explanation follows below.

[0070] When the positional displacement calculation unit 131 starts processing (Start), it determines whether dAD[NL] <- TH[NLY] (step S1).

[0071] If the positional displacement calculation unit 131 determines that dAD[NL] <-TH[NLY] (S1:Yes), it then determines whether dAD[SL] > TH[SLY] (step S2). The meaning of the flowcharts for steps S1 and S2 will be explained. As shown in Figure 6C, when a displacement occurs in the +Y direction of the sensor unit 150, the position of the electrostatic sensor NL relative to the metal member 11 becomes at the edge or outside of the metal member 11 compared to when it is in the reference position, and the area of ​​the metal member 11 that contributes to the capacitance of the electrostatic sensor NL becomes smaller compared to when it is in the reference position. As a result, the capacitance between the electrostatic sensor NL and the metal member 11 becomes smaller, and the difference value ΔAD of the electrostatic sensor NL also becomes smaller compared to the reference position. In other words, the fluctuation value dAD[NL] becomes smaller as the displacement in the +Y direction increases. In step S1, if the difference value of electrode NL decreases by more than a predetermined value compared to the reference value, it is determined that a displacement in the +Y direction has occurred (S1:Yes).

[0072] Furthermore, as shown in Figure 6C, if the sensor unit 150 is displaced in the +Y direction, the position of the electrostatic sensor SL relative to the metal member 11 will be centered on the metal member 11 compared to when it is in the reference position. As a result, the area of ​​the metal member 11 that contributes to the capacitance of the electrostatic sensor SL becomes larger compared to when it is in the reference position. Consequently, the capacitance between the electrostatic sensor SL and the metal member 11 increases, and the difference value ΔAD of the electrostatic sensor SL also becomes larger compared to the reference position. In other words, dAD[SL] increases as the displacement in the +Y direction increases. In step S2, if the difference value of electrode SL increases by more than a predetermined value compared to the reference value, it is determined that a displacement in the +Y direction has occurred (S2: Yes).

[0073] When the positional displacement calculation unit 131 determines that dAD[SL]>TH[SLY] (S2:Yes), it determines that a displacement in the +Y direction has occurred in the sensor unit 150 for both the electrostatic sensor NL and the electrostatic sensor SL. Therefore, it determines that a displacement has actually occurred and calculates the Y-direction positional displacement dY of the eight electrostatic sensors 110 (step S3). After completing the processing in step S3, the positional displacement calculation unit 131 proceeds to step S11.

[0074] If the positional displacement calculation unit 131 determines in step S1 that dAD[NL] <-TH[NLY] is not true (S1: No), it then determines whether dAD[SL] <-TH[SLY] (step S4). This is to determine whether the positional displacement is in the -Y direction.

[0075] If the positional displacement calculation unit 131 determines that dAD[SL] <-TH[SLY] (S4: Yes), it then determines whether dAD[NL] > TH[NLY] (step S5). This is to determine whether the positional displacement is in the -Y direction.

[0076] The meaning of the flowchart in steps S4-S5 is the same as explained in S1-S2 above. However, because the sensor unit 150 shifts in the -Y direction, the increase or decrease of the difference value ΔAD between electrostatic sensors NL and SL relative to the reference position is the opposite of when it shifts in the +Y direction. The difference value ΔAD of electrostatic sensor SL becomes smaller than the reference position, and the difference value ΔAD of electrostatic sensor NL becomes larger than the reference position. The flowchart determines whether these values ​​are in this relationship.

[0077] When the positional displacement calculation unit 131 determines that dAD[NL]>TH[NLY] (S5:Yes), it determines that a displacement in the -Y direction has occurred in the sensor unit 150 for both electrostatic sensor NL and electrostatic sensor SL. Therefore, it determines that a displacement has actually occurred and proceeds to step S3, where the positional displacement dY in the Y direction of the eight electrostatic sensors 110 is calculated (step S3).

[0078] If the positional displacement calculation unit 131 determines in step S4 that dAD[SL] <-TH[SLY] is not true (S4: No), it determines that the positional displacement dY of the sensor unit 150, i.e., the eight electrostatic sensors 110, in the +Y and -Y directions is less than or equal to a predetermined value, and is therefore 0 (dY=0) (step S6).

[0079] If it is determined in step S2 that dAD[SL] > TH[SLY] is not true (S2: No), or if it is determined in step S5 that dAD[NL] > TH[NLY] is not true (S5: No), then the Y-direction positional deviation dY of the eight electrostatic sensors 110 is less than or equal to a predetermined value and is considered to be at a level that can be ignored, and is determined to be 0 (dY=0) (step S6). In step S6, dY is considered to be 0 (dY=0).

[0080] If the result in step S2 is determined to be "No," it means that a displacement in the +Y direction was determined in step S1, and therefore no displacement in the +Y direction was determined in step S2, resulting in a different determination result. Similarly, if the result in step S5 is determined to be "No," it means that a displacement in the -Y direction was determined in step S4, and therefore no displacement in the -Y direction was determined in step S5, resulting in a different determination result. In this embodiment, if different determination results are obtained, it is determined that there is no displacement. This is because the occurrence of positional displacement and its correction are exceptional, so if different determination results are obtained, it is unclear whether there is actually a positional displacement, and in that case, no correction is performed. However, if either the electrostatic sensor NL or the electrostatic sensor SL determines that there is a positional displacement, correction will be performed, or other factors may be taken into consideration to determine whether there is a positional displacement.

[0081] In step S3, the positional displacement dY in the Y direction of the eight electrostatic sensors 110 can be calculated as follows, for example.

[0082] The positional displacement dY is the positional displacement in the -Y direction (S direction) or the +Y direction (N direction). The positional displacement calculation unit 131 sets the positional displacement dY to the smaller of the absolute values ​​of dAD[SL] and dAD[NL]. This is because, even if a positional displacement occurs, it is not expected to be large, so the smaller absolute value is more likely to be correct. Also, since the occurrence of positional displacement and its correction are exceptional, this is to minimize the impact of correction. Alternatively, it may be set to the larger of the two absolute values, or to the average of the absolute values.

[0083] Although the misalignment dY is a length, since the misalignment dY corresponds to the magnitude of dAD[SL] and dAD[NL], here we will use dAD[SL]d or dAD[NL] as the misalignment dY. In this embodiment, the misalignment calculation unit 131 sets dAD[SL]d or dAD[NL], which are values ​​corresponding to the misalignment, as the misalignment dY, but in reality, the misalignment dY may also be calculated from the capacity value or calculated using a comparison table.

[0084] <Steps S11-S16> Steps S11 to S16 determine whether there is a displacement in the X direction as shown in Figure 6B. In general, steps S11 and S12 determine whether there is a displacement in the +X direction, and steps S14 and S15 determine whether there is a displacement in the -X direction, and each step is the same as steps S1 to S6.

[0085] The positional displacement calculation unit 131 determines whether dAD[EL] <- TH[ELX] (step S11).

[0086] If the positional displacement calculation unit 131 determines that dAD[EL] <-TH[ELX] (S11:Yes), it then determines whether dAD[WL] > TH[WLX] (step S12). The meaning of the flowcharts for steps S11 to S12 will be explained. As shown in Figure 6B, when a displacement occurs in the +X direction of the sensor unit 150, the position of the electrostatic sensor EL relative to the metal member 11 becomes at the edge or outside of the metal member 11 compared to when it is in the reference position, and the area of ​​the metal member 11 that contributes to the capacitance of the electrostatic sensor EL becomes smaller compared to when it is in the reference position. As a result, the capacitance between the electrostatic sensor EL and the metal member 11 becomes smaller, and the difference value ΔAD of the electrostatic sensor EL also becomes smaller compared to the reference position. That is, the fluctuation value dAD[EL] becomes smaller as the displacement in the +X direction increases. In step S11, if the difference value of electrode EL decreases by more than a predetermined value compared to the reference value, it is determined that a displacement in the +X direction has occurred (S11:Yes).

[0087] Furthermore, as shown in Figure 6B, if the sensor unit 150 is displaced in the +X direction, the position of the electrostatic sensor WL relative to the metal member 11 will be centered on the metal member 11 compared to when it is in the reference position. As a result, the area of ​​the metal member 11 that contributes to the capacitance of the electrostatic sensor WL becomes larger compared to when it is in the reference position. Consequently, the capacitance between the electrostatic sensor WL and the metal member 11 increases, and the difference value ΔAD of the electrostatic sensor WL also becomes larger compared to the reference position. In other words, dAD[WL] increases as the displacement in the +X direction increases. In step S12, if the difference value of electrode WL increases by more than a predetermined value compared to the reference value, it is determined that a displacement in the +X direction has occurred (S12: Yes).

[0088] If the positional displacement calculation unit 131 determines that dAD[WL] > TH[WLX] (S12: Yes), it determines that a displacement in the +X direction has occurred in the sensor unit 150 for both the electrostatic sensor EL and the electrostatic sensor WL. Therefore, it determines that a displacement has actually occurred and calculates the X-direction positional displacement dX of the eight electrostatic sensors 110 (step S13). After completing the processing in step S13, the positional displacement calculation unit 131 proceeds to step S21.

[0089] If the positional displacement calculation unit 131 determines in step S11 that dAD[EL] <-TH[ELX] is not true (S11: No), it then determines whether dAD[WL] <-TH[WLX] (step S14). This is to determine whether the positional displacement is in the -X direction.

[0090] If the positional displacement calculation unit 131 determines that dAD[WL] <-TH[WLX] (S14: Yes), it then determines whether dAD[EL] > TH[ELX] (step S15). This is to determine whether the positional displacement is in the -X direction. The meaning of the flowchart in steps S14 to S15 is the same as explained in S11 to S12 above, but because the sensor unit 150 is shifted in the -X direction, the increase or decrease of the difference value ΔAD between the electrostatic sensor EL and WL relative to the reference position is reversed, so the difference value ΔAD of the electrostatic sensor WL becomes smaller than the reference position, and the difference value ΔAD of the electrostatic sensor EL becomes larger than the reference position.

[0091] When the positional displacement calculation unit 131 determines that dAD[EL]>TH[ELX] (S15:Yes), it determines that a displacement in the -X direction has occurred in the sensor unit 150 for both the electrostatic sensor EL and the electrostatic sensor WL. Therefore, it determines that a displacement has actually occurred and proceeds to step S13, where the X-direction positional displacement dX of the eight electrostatic sensors 110 is calculated (step S13).

[0092] If the positional deviation calculation unit 131 determines in step S14 that dAD[WL] <-TH[WLX] is not true (S14: No), it determines that the positional deviation dX of the sensor unit 150, i.e., the eight electrostatic sensors 110, in the +X and -X directions is less than or equal to a predetermined value, and is therefore 0 (dX=0) (step S16).

[0093] In step S12, if it is determined that dAD[WL] > TH[WLX] is not true (S12: No), or in step S15, if it is determined that dAD[EL] > TH[ELX] is not true (S15: No), then the X-direction positional deviation dX of the eight electrostatic sensors 110 is less than or equal to a predetermined value and is considered to be at a level that can be ignored, and is determined to be 0 (dX=0) (step S16). In step S16, dX is considered to be 0 (dX=0).

[0094] If the result in step S12 is "No," it means that a displacement in the +X direction was determined in step S11, and therefore in step S12, it was determined that there was no displacement in the +X direction, resulting in a different determination result. Similarly, if the result in step S15 is "No," it means that a displacement in the -X direction was determined in step S14, and therefore in step S15, it was determined that there was no displacement in the -X direction, resulting in a different determination result. In this embodiment, if different determination results are obtained, it is determined that there is no displacement in the X direction. This is similar to the determination of positional displacement in the Y direction, and since the occurrence of positional displacement and its correction are exceptional, if different determination results are obtained, it is unclear whether there is actually a positional displacement, so in that case, no correction is performed. However, if either the electrostatic sensor NL or the electrostatic sensor SL determines that there is a positional displacement, a correction will be performed, or other factors may be taken into consideration to determine whether there is a positional displacement.

[0095] In step S13, the positional displacement dX in the X direction of the eight electrostatic sensors 110 can be calculated as follows, for example.

[0096] The positional displacement dX is the positional displacement in the -X direction (W direction) or the +X direction (E direction). The positional displacement calculation unit 131 sets the positional displacement dX to the smaller of the absolute values ​​of dAD[WL] and dAD[EL]. This is because, similar to when determining the positional displacement dY in the Y direction, even if a positional displacement occurs, it is not expected to be large, so the smaller absolute value is more likely to be correct. Also, since the occurrence of positional displacement and its correction are exceptional, this is also to minimize the influence of correction. Alternatively, it may be set to the larger of the two absolute values, or to the average of the absolute values.

[0097] Although the misalignment dX is a length, since the misalignment dX corresponds to the magnitude of dAD[EL] and dAD[WL], here we will use dAD[EL]d or dAD[WL] as the misalignment dX. In this embodiment, the misalignment calculation unit 131 sets dAD[EL]d or dAD[WL], which are values ​​corresponding to the misalignment, as the misalignment dX, but in reality, the misalignment dX may be calculated from the capacity value or calculated using a comparison table.

[0098] <Steps S21-S26> In steps S21 to S26, it is determined whether there is a rotational displacement around the Z-axis as shown in Figure 6D.

[0099] The positional displacement calculation unit 131 determines whether dAD[NL] > TH[RZ] (step S21).

[0100] If the positional displacement calculation unit 131 determines that dAD[NL] > TH[RZ] (S21: Yes), it then determines whether dAD[SL] > TH[RZ] (step S22).

[0101] If the positional displacement calculation unit 131 determines that dAD[SL] > TH[RZ] (S22: Yes), it then determines whether dAD[EL] > TH[RZ] (step S23).

[0102] When the displacement calculation unit 131 determines that dAD[EL] > TH[RZ] (S23: Yes), it determines whether dAD[WL] > TH[RZ] (step S24).

[0103] When the displacement calculation unit 131 determines that dAD[WL] < TH[Z] (S24: Yes), it calculates the rotational displacement dRZ in the Z-axis direction of the eight electrostatic sensors 110 (step S25).

[0104] That is, as shown in FIG. 6D, when a displacement occurs in the rotational direction around the Z-axis in the sensor unit 150, since the electrostatic sensors 110 rotate around the Z-axis, each of the electrostatic sensors NL, SL, EL, WL approaches a region along the diagonal of the metal member 11, that is, a region where the area of the metal member 11 is large, compared to the case where they are in the reference position. Therefore, the area of the metal member 11 that contributes to the capacitance of each of the electrostatic sensors NL, SL, EL, WL becomes larger than in the case where they are in the reference position. As a result, the difference value ΔAD of each of the electrostatic sensors NL, SL, EL, WL also becomes larger than in the reference position. If the displacement in the rotational direction around the Z-axis is 90 degrees, the area of the metal member 11 that contributes to the capacitance does not change and the capacitance value also does not change compared to the reference position. However, the rotational displacement around the Z-axis is less than at least 90 degrees, and usually several degrees or less even if there is a displacement. Therefore, each of the electrostatic sensors NL, SL, EL, WL is located in a region along the diagonal of the metal member 11, that is, a region where the area of the metal member 11 is large, compared to the case where they are in the reference position. So the actual difference value ΔAD of the electrostatic sensors is larger than the difference value ΔAD at the reference position. Note that the electrostatic sensors NL, SL, EL, WL increase in the same way when the sensor unit 150 rotates around the Z-axis.

[0105] When the displacement calculation unit 131 determines No in step S21, S22, S23, or S24, it determines that the rotational displacement dRz in the Z-axis direction of the eight electrostatic sensors 110 is below a predetermined value and can be ignored as being at an acceptable level, and is 0 (dRz = 0) (step S26).

[0106] By the way, if the result in step S22, S23, or S24 is No, the result of the previous steps was Yes, meaning that there is a positional displacement around the Z axis, so the result is different, and it is unclear whether there is actually a positional displacement. However, since the occurrence of a positional displacement and its correction are exceptional, if the judgment result is different, no correction is performed. However, if any or more of the electrostatic sensors NL, SL, EL, WL are above a threshold, it may be determined that a rotational displacement around the Z axis has occurred.

[0107] In step S25, the rotational displacement dRz of the eight electrostatic sensors 110 around the Z-axis can be calculated as follows, for example.

[0108] The positional displacement calculation unit 131 sets the positional displacement dRz to the smallest absolute value among dAD[NL], dAD[SL], dAD[EL], and dAD[WL].

[0109] This is because, even if a positional shift occurs, it is unlikely to be significant, so the smaller absolute value is more likely to be correct. Furthermore, since the occurrence of positional shifts and their correction are exceptional, this also helps to minimize the impact of corrections. Alternatively, one could set the value to the largest absolute value, or use the average of the absolute values.

[0110] Although the unit of positional displacement dRz is angles, the positional displacement dRz corresponds to the magnitude of dAD[NL], dAD[SL], dAD[EL], and dAD[WL]. Therefore, here we will use dAD[NL] or dAD[SL], dAD[EL], and dAD[WL] as the positional displacement dRz.

[0111] In this embodiment, the misalignment calculation unit 131 sets the misalignment dRz to a value corresponding to the misalignment, such as dAD[NL], dAD[SL], dAD[EL], or dAD[WL]. However, the misalignment dRz may actually be calculated from the capacitance value or calculated using a comparison table.

[0112] This completes the process of steps S1 to S26 for determining the positional displacement dX, dY, and dRz around the X, Y, and Z axes (END).

[0113] <Steps S31-S55> Next, we will explain how to determine the positional displacements dRx, dRy, and dZ around the X, Y, and Z axes shown in Figure 7, using Figure 8B.

[0114] Figure 8B is a flowchart showing an example of the process executed by the positional misalignment calculation unit 131 when any of the positional misalignments shown in Figure 7 are expected. Note that if the mounting mechanism only causes a predetermined positional misalignment, for example, a positional misalignment around the X-axis, when mounting the metal member 11 and the sensor unit 150, then only the positional misalignment around the X-axis shown in steps S31 to S36 may be calculated.

[0115] <Steps S31-S35> In steps S31 to S35, it is determined whether there is a positional displacement dRx around the X-axis as shown in Figure 7B.

[0116] First, when the positional displacement calculation unit 131 starts processing (Start), it determines whether dAD[NL]>0 and dAD[SL]<0, or whether dAD[SL]>0 and dAD[NL]<0 (step S31).

[0117] The reason for determining whether dAD[NL]>0 and dAD[SL]<0 is to determine whether the electrostatic sensor NL has shifted in the -Z direction and is approaching the metal member 11, and whether the electrostatic sensor SL has shifted in the +Z direction and is moving away from the metal member 11. The fact that the electrostatic sensor NL has shifted in the -Z direction and the electrostatic sensor SL has shifted in the +Z direction indicates that the eight electrostatic sensors 110 have rotated and shifted around the X axis as shown in Figure 7B.

[0118] The reason for determining whether dAD[SL]>0 and dAD[NL]<0 is to determine whether the electrostatic sensor SL has shifted in the -Z direction and is approaching the metal member 11, and whether the electrostatic sensor NL has shifted in the +Z direction and is moving away from the metal member 11. The fact that the electrostatic sensor SL has shifted in the -Z direction and the electrostatic sensor NL has shifted in the +Z direction indicates that the eight electrostatic sensors 110 have rotated and shifted around the X axis in the opposite direction to that shown in Figure 7B.

[0119] The positional displacement calculation unit 131 determines whether dAD[NL]-dAD[SL]>TH[RX] (step S32). dAD[NL]-dAD[SL]>TH[RX] means that, as shown in Figure 7B, when viewed from the -X direction, the eight electrostatic sensors 110 are rotating counterclockwise around the X axis, and the amount of rotation is greater than or equal to a predetermined value.

[0120] If the positional displacement calculation unit 131 determines that dAD[NL]-dAD[SL]>TH[RX] (S32:Yes), it calculates the positional displacement dRx around the X axis (step S33).

[0121] If the positional displacement calculation unit 131 determines in step S32 that dAD[NL]-dAD[SL]>TH[RX] is not true (S32: No), it then determines whether dAD[SL]-dAD[NL]>TH[RX] (step S34). This is to determine whether the eight electrostatic sensors 110 have rotated more than a predetermined amount clockwise around the X axis when viewed from the +X direction side.

[0122] If the positional displacement calculation unit 131 determines that dAD[SL]-dAD[NL]>TH[RX] (S34:Yes), the flow proceeds to step S33, and the positional displacement dRx around the X axis is calculated (step S33).

[0123] In step S31, the positional displacement calculation unit 131 determines that dAD[NL] > 0 and dAD[SL] < 0, and simultaneously dAD[SL] > 0 and dAD[NL] < 0 (S31: No), or in step S34, it determines that dAD[SL] - dAD[NL] > TH[RX] (S34: No), in which case the positional displacement dRx of the eight electrostatic sensors 110 around the X axis is 0 (dRx = 0) (step S35). In step S35, dRx is considered to be 0 (dRx = 0), or there is a positional displacement around the X axis, but it is negligible and therefore dRx is considered to be 0 (dRx = 0).

[0124] The positional displacement calculation unit 131 calculates the positional displacement dRx around the X-axis as follows:

[0125] The positional displacement dRx is the positional displacement in the clockwise or counterclockwise direction around the X-axis. The positional displacement calculation unit 131 sets the value of dAD[NL]-dAD[SL] if Yes in step S32, and the value of dAD[SL]-dAD[NL] if Yes in step S34.

[0126] Although the positional displacement dRx is an angle, it corresponds to the magnitude of dAD[NL]-dAD[SL] or dAD[SL]-dAD[NL]. Therefore, here we define the positional displacement dRx as dAD[NL]-dAD[SL] or dAD[SL]-dAD[NL].

[0127] In this embodiment, the positional displacement calculation unit 131 sets the positional displacement dRx to a value corresponding to the positional displacement, such as dAD[NL]-dAD[SL] or dAD[EL]-dAD[WL]. However, the positional displacement dRx may actually be calculated from the capacitance value or calculated using a comparison table.

[0128] <Steps S41-S45> Steps S41 to S45 determine the positional displacement dRy around the Y axis, as shown in Figure 7C, and are basically equivalent to steps S31 to S35, which determine the positional displacement dRx around the X axis.

[0129] The positional deviation calculation unit 131 determines whether dAD[WL]>0 and dAD[EL]<0, or whether dAD[EL]>0 and dAD[WL]<0 (step S41).

[0130] The reason for determining whether dAD[WL]>0 and dAD[EL]<0 is to determine whether the electrostatic sensor WL is shifted in the -Z direction and is close to the metal member 11, and whether the electrostatic sensor EL is shifted in the +Z direction and is separated from the metal member 11. The fact that the electrostatic sensor WL is shifted in the -Z direction and the electrostatic sensor EL is shifted in the +Z direction indicates that the eight electrostatic sensors 110 are rotated and shifted around the Y axis, as shown in Figure 7C.

[0131] The reason for determining whether dAD[EL]>0 and dAD[WL]<0 is to determine whether the electrostatic sensor EL has shifted in the -Z direction and is approaching the metal member 11, and whether the electrostatic sensor WL has shifted in the +Z direction and is moving away from the metal member 11. The fact that the electrostatic sensor EL has shifted in the -Z direction and the electrostatic sensor WL has shifted in the +Z direction indicates that the eight electrostatic sensors 110 have rotated and shifted around the Y axis in the opposite direction to that shown in Figure 7B.

[0132] The positional displacement calculation unit 131 determines whether dAD[WL]-dAD[EL]>TH[RY] (step S42). dAD[WL]-dAD[EL]>TH[RY] means that, as shown in Figure 7C, when viewed from the -Y direction, the eight electrostatic sensors 110 are rotating counterclockwise around the Y axis, and the amount of rotation is greater than or equal to a predetermined value.

[0133] If the positional displacement calculation unit 131 determines that dAD[WL]-dAD[EL]>TH[RY] (S42:Yes), it calculates the positional displacement dRy around the Y axis (step S43).

[0134] If the positional displacement calculation unit 131 determines in step S42 that dAD[WL]-dAD[EL]>TH[RY] is not true (S42: No), it then determines whether dAD[EL]-dAD[WL]>TH[RY] (step S44). This is to determine whether the eight electrostatic sensors 110 have rotated more than a predetermined amount clockwise around the Y axis when viewed from the Y direction side.

[0135] If the positional displacement calculation unit 131 determines that dAD[EL]-dAD[WL]>TH[RY] (S44:Yes), the flow proceeds to step S43, and the positional displacement dRy around the Y axis is calculated (step S43).

[0136] In step S41, the positional displacement calculation unit 131 determines that dAD[WL] > 0 and dAD[EL] < 0, and simultaneously dAD[EL] > 0 and dAD[WL] < 0 (S41: No), or in step S44, it determines that dAD[EL] - dAD[WL] > TH[RY] (S44: No), in which case it determines that the positional displacement dRy of the eight electrostatic sensors 110 around the Y axis is 0 (dRy=0) (step S45). In step S45, dRy is considered to be 0 (dRy=0), or there is a positional displacement around the Y axis, but it is considered to be negligible and therefore dRy is 0 (dRy=0).

[0137] The positional displacement calculation unit 131 calculates the positional displacement dRy around the Y axis as follows.

[0138] The positional deviation dRy is the positional deviation in the clockwise or counterclockwise direction around the Y axis. The positional deviation calculation unit 131 sets the value of dAD[WL]-dAD[EL] if Yes in step S42, and the value of dAD[EL]-dAD[WL] if Yes in step S44.

[0139] Although the displacement dRy is an angle, since the displacement dRy is a value corresponding to the magnitude of dAD[WL] - dAD[EL] or dAD[EL] - dAD[WL], here, dAD[WL] - dAD[EL] or dAD[EL] - dAD[WL] is taken as the displacement dRy.

[0140] In this embodiment, although the displacement calculation unit 131 sets dAD[WL] - dAD[EL] or dAD[EL] - dAD[WL], which is a value corresponding to the displacement, as the displacement dRy, actually, the displacement dRy may be calculated from the capacitance value or by means of a comparison table.

[0141] <Steps S51 to S56> Steps S51 to S56 determine whether there is a displacement dZ in the Z-axis direction shown in FIG. 7D.

[0142] The displacement calculation unit 131 determines whether dAD[NL] < TH[Z] (step S51).

[0143] When the displacement calculation unit 131 determines that dAD[NL] < TH[Z] (S51: Yes), it determines whether dAD[SL] < TH[Z] (step S52).

[0144] When the displacement calculation unit 131 determines that dAD[SL] < TH[Z] (S52: Yes), it determines whether dAD[EL] < TH[Z] (step S53).

[0145] When the displacement calculation unit 131 determines that dAD[EL] < TH[Z] (S53: Yes), it determines whether dAD[WL] < TH[Z] (step S54).

[0146] When the displacement calculation unit 131 determines that dAD[WL] < TH[Z] (S54: Yes), it calculates the Z-axis displacement dZ of the eight electrostatic sensors 110 (step S55).

[0147] In other words, as shown in Figure 7D, when the sensor unit 150 is displaced in the +Z direction, the electrostatic sensor 110 moves in the +Z direction. As a result, each electrostatic sensor NL, SL, EL, and WL moves further away from the metal member 11 compared to when it is in the reference position. Therefore, the difference value ΔAD of each electrostatic sensor NL, SL, EL, and WL becomes smaller than when it is in the reference position. If it is smaller than the threshold TH[Z] (a negative value), i.e., if it has decreased by a predetermined value or more, it is determined that there is a positional displacement. Similarly, the electrostatic sensors NL, SL, EL, and WL decrease when the sensor unit 150 is displaced in the +Z direction.

[0148] If the positional deviation calculation unit 131 determines No in step S51, S52, S53, or S54, it determines that the positional deviation dZ in the Z direction of the eight electrostatic sensors 110 is less than or equal to a predetermined value and is at a level that can be ignored, and determines that it is 0 (dZ=0) (step S56).

[0149] By the way, if the result in step S52, S53, or S54 is No, the result of the previous steps was Yes, meaning that there is a positional displacement in the Z direction, so it is unclear whether there is actually a positional displacement. However, since the occurrence of a positional displacement and the correction of it are exceptional, if a different judgment result is obtained, in that case no correction is performed. However, it is also acceptable to determine that a Z-direction displacement has occurred if any or more of the electrostatic sensors NL, SL, EL, WL are below a threshold.

[0150] In step S55, the Z-direction positional displacement dZ of the eight electrostatic sensors 110 can be calculated as follows, for example.

[0151] The positional displacement calculation unit 131 determines the positional displacement dZ as the value with the smallest absolute value among dAD[NL], dAD[SL], dAD[EL], and dAD[WL].

[0152] This is because, even if a positional shift occurs, it is unlikely to be significant, so the smaller absolute value is more likely to be correct. Furthermore, since the occurrence of positional shifts and their correction are exceptional, this also helps to minimize the impact of corrections. Alternatively, one could set the value to the largest absolute value, or use the average of the absolute values.

[0153] Although the unit of positional displacement dZ is distance, the positional displacement dZ corresponds to the magnitude of dAD[NL], dAD[SL], dAD[EL], and dAD[WL]. Therefore, here we will define the positional displacement dZ as dAD[NL] or dAD[SL], dAD[EL], or dAD[WL].

[0154] Furthermore, in this embodiment, the positional displacement calculation unit 131 sets the positional displacement dZ to a value corresponding to the positional displacement, such as dAD[NL], dAD[SL], dAD[EL], or dAD[WL]. However, the positional displacement dZ may actually be calculated from the capacitance value or calculated using a comparison table.

[0155] This completes the process of steps S31 to S56 for determining the positional displacements dRx, dRy, and dZ around the X, Y, and Z axes (END).

[0156] <Calculation of Correction Value> Next, the calculation of the correction value performed in the correction value calculation unit 132 and the calculation of the correction coefficient required for calculating the correction value will be explained. The correction coefficient is a coefficient required to correct for positional misalignment with respect to the difference value ΔAD measured at each electrode in the actual usage state. In other words, the correction value is the difference value ΔAD in the actual usage state corrected according to the positional misalignment, and is a predicted value that would be measured if the sensor unit 150 were placed at the reference position. In this embodiment, it is obtained by multiplying the difference value ΔAD of the actual measured value in the actual usage state by the correction coefficient. The threshold value used to determine whether contact or approach has occurred with any of the operation units 21A is set based on the difference value AD when the sensor unit 150 is mounted at the reference position. Therefore, by obtaining a correction value for the difference value ΔAD corresponding to the measured value, more accurate determination is possible.

[0157] First, we will explain how to determine the correction value when a positional misalignment occurs, as shown in Figure 6. This is done after the operation shown in the flowchart in Figure 8A.

[0158] In step S3, the positional displacement dY is set to the value of the smaller absolute value between dAD[SL] and dAD[NL]. If the absolute value of dAD[SL] is small, the correction coefficient k1 is calculated as follows.

[0159] k1 = (Difference value at reference position ΔAD[SL] / Actual difference value ΔAD[SL])

[0160] In other words, the correction coefficient k is determined by the capacitance value of the electrode corresponding to the smaller of the absolute values ​​of dAD[SL] and dAD[NL]. The denominator is the difference value ΔAD of the electrodes measured when the sensor unit 150 is actually attached to the metal member 11 and there are no objects to be detected, such as fingertips, in the vicinity. The numerator is the difference value ΔAD of the electrodes measured when the sensor unit 150 is attached to the metal member 11 in a reference position without any displacement and there are no objects to be detected, such as fingertips, in the vicinity.

[0161] Then, the correction coefficient k1 is stored in memory, and when a detection target such as a fingertip comes into close proximity during actual use, the difference value ΔAD is calculated from the actual digital value AD of electrode SL, and the correction value of electrode SL is obtained by multiplying it by the correction coefficient k1.

[0162] Furthermore, for electrode NL, the difference value ΔAD is calculated from the actual digital value AD, and the correction value for electrode NL is obtained by multiplying it by a correction coefficient of 1 / (k1). As mentioned above, when shifted in the Y direction, one of the opposing electrodes increases and the other decreases compared to the reference position, and the actual digital values ​​AD of electrode SL and electrode NL are measured as approximately k1 times the value of one and 1 / (k1) times the value of the other compared to when measured at the reference position. Therefore, by correcting each by 1 / (k1) or k1, the difference value ΔAD that would be measured when the electrode is attached to the metal member 11 at the reference position can be estimated.

[0163] The same applies when dAD[NL] is smaller than dAD[SL], and the correction coefficient k2 is calculated as follows.

[0164] k2 = (Difference value at reference position ΔAD[NL] / Actual difference value ΔAD[NL])

[0165] Then, the correction coefficient k2 is stored in memory, and when a detection target such as a fingertip comes into close proximity during actual use, the difference value ΔAD is calculated from the actual digital value AD of electrode NL, and the correction value of electrode NL is obtained by multiplying it by the correction coefficient k2. Also, if dAD[NL] is smaller than dAD[SL], the same procedure as explained for electrode SL is followed: the difference value ΔAD is calculated from the actual digital value AD, and the correction value of electrode SL is obtained by multiplying it by the correction coefficient 1 / (k2).

[0166] In the above embodiment, the formula for calculating the correction coefficient was changed depending on whether dAD[SL] or dAD[NL] was smaller. However, it is also possible to calculate the respective correction values ​​by first calculating the correction coefficient k3 for electrode SL using k3 = (difference value ΔAD[SL] at the reference position / actual difference value ΔAD[SL]) and the correction coefficient k4 for electrode NL using k4 = (difference value ΔAD[NL] at the reference position / actual difference value ΔAD[NL]).

[0167] If dY=0 is determined in step S6, the correction coefficient k is set to 1 and no correction is performed.

[0168] The method for determining the correction coefficient k and the correction value after step S13 is the same as the method for calculating the correction coefficient after step S3 described above. In step 13, if dAD[WL] is smaller than dAD[EL], the correction coefficient k5 is determined as follows.

[0169] k5 = (Difference value at reference position ΔAD[WL] / Actual difference value ΔAD[WL])

[0170] Then, the correction coefficient k5 is stored in memory, and when a detection target such as a fingertip comes into close proximity during actual use, the difference value ΔAD is calculated from the actual digital value AD of electrode WL, and the correction value of electrode WL is obtained by multiplying it by the correction coefficient k5. Similarly, for electrode EL, the difference value ΔAD is calculated from the actual digital value AD, and the correction value of electrode EL is obtained by multiplying it by the correction coefficient 1 / (k5).

[0171] If dAD[EL] is smaller than dAD[WL], the correction factor k6 is calculated as follows.

[0172] k6 = (Difference value at reference position ΔAD[EL] / Actual difference value ΔAD[EL])

[0173] Then, the correction coefficient k6 is stored in memory, and when a detection target such as a fingertip comes into close proximity during actual use, the difference value ΔAD is calculated from the actual digital value AD of electrode EL, and the correction value of electrode EL is obtained by multiplying it by the correction coefficient k6. Similarly, for electrode WL, the difference value ΔAD is calculated from the actual digital value AD, and the correction value of electrode WL is obtained by multiplying it by the correction coefficient 1 / (k6).

[0174] In the above embodiment, the formula for calculating the correction coefficient was changed depending on whether dAD[WL] or dAD[EL] was smaller. However, it is also possible to calculate the respective correction values ​​by calculating the correction coefficient k7 for electrode WL using k7 = (difference value ΔAD[WL] at the reference position / actual difference value ΔAD[WL]) and the correction coefficient k8 for electrode EL using k8 = (difference value ΔAD[EL] at the reference position / actual difference value ΔAD[EL]).

[0175] If it is determined that dX=0 in step S16, the correction coefficient k is set to 1 and no correction is performed.

[0176] In step S25, the misalignment dRz is set to the value with the smallest absolute value among dAD[NL], dAD[SL], dAD[EL], and dAD[WL]. The correction coefficient k9 is calculated for the electrode corresponding to this value, and the correction values ​​for the other electrodes are also corrected using the same correction coefficient k9. For example, if dAD[NL] is the smallest, the correction coefficient k9 is calculated as k9 = (difference value ΔAD[NL] at the reference position / actual difference value ΔAD[NL]), and the correction coefficients k for electrodes SL, EL, and WL are also set to the same value k9.

[0177] In the above embodiment, the correction coefficient was calculated for the electrode corresponding to the smallest absolute value among dAD[NL], dAD[SL], dAD[EL], and dAD[WL]. However, the correction coefficient and correction value may be calculated for each electrode using the same formula.

[0178] If it is determined in step S26 that dRz=0, the correction coefficient k is set to 1 and no correction is performed.

[0179] The above describes how to determine the correction values ​​for the lower electrodes NL, SL, EL, and WL. However, for the upper electrodes NU, SU, EU, and WU, the correction coefficient k obtained for the lower electrodes NL, SL, EL, and WL is used as the correction coefficient k for the upper electrode corresponding to each electrode. This is because determining the correction coefficient k for the lower electrodes results in larger absolute values ​​for ΔAD and dAD since they are closer to the metal component 11, allowing for more accurate determination of the deviation. The correction values ​​for the upper electrodes NU, SU, EU, and WU can also be determined using the same method as for the lower electrodes NL, SL, EL, and WL.

[0180] Next, we will explain how the correction value is determined in the correction value calculation unit 132 when a positional misalignment occurs between the sensor unit 150 shown in Figure 7 and the metal member 11. This is performed after the operation shown in the flowchart of Figure 8B. In step S33, the positional misalignment dRx is set to dAD[NL]-dAD[SL] or dAD[SL]-dAD[NL], and the correction coefficient k10 for electrode NL is calculated as k10 = (difference value ΔAD[NL] at the reference position / actual difference value ΔAD[NL]). The correction coefficient k11 for electrode SL is calculated as k11 = (difference value ΔAD[SL] at the reference position / actual difference value ΔAD[SL]).

[0181] In this case, since the rotation angle deviation dAD[SL]-dAD[NL], or dAD[SL]-dAD[NL], both dAD[SL] and dAD[NL] are values ​​corresponding to angles, the correction coefficients k10 and k11 will also be values ​​corresponding to the deviation dRx.

[0182] Then, the correction coefficients k10 and k11 are stored in memory, and when a detection target such as a fingertip comes into close proximity during actual use, the difference value ΔAD is calculated from the actual digital value AD of electrode NL or electrode SL, and the correction value of electrode NL or electrode SL is obtained by multiplying it by the correction coefficient k10 or k11.

[0183] Alternatively, in step 33, dRx may be set to the smaller of the absolute values ​​of AD[NL] and dAD[SL], and the correction values ​​may be calculated by multiplying the difference value ΔAD of each electrode by the correction coefficient k12 for the electrode with the smaller absolute value of dAD[SL] and dAD[NL], and by the correction coefficient 1 / (k12), similar to the method for calculating the correction values ​​after step 3.

[0184] If dRx=0 is determined in step S35, the correction coefficient k is set to 1 and no correction is performed.

[0185] The method for determining the correction value after setting the positional misalignment dRy as dAD[WL]-dAD[EL] or dAD[EL]-dAD[WL] in step S43 is the same as the method for determining the correction value after setting dRx in step 33 described above.

[0186] The correction coefficient k for electrode WL is calculated as k13 = (difference value ΔAD[WL] at the reference position / actual difference value ΔAD[WL]). The correction coefficient k for electrode EL is calculated as k14 = (difference value ΔAD[EL] at the reference position / actual difference value ΔAD[EL]).

[0187] Similarly, both the correction coefficients k13 and k14 correspond to the values ​​of dRy.

[0188] Then, the correction coefficients k13 and k14 are stored in memory, and when a detection target such as a fingertip comes into close proximity during actual use, the difference value ΔAD is calculated from the actual digital value AD of electrode WL or electrode EL, and the correction value of electrode WL or electrode EL is obtained by multiplying it by the correction coefficient k13 or k14.

[0189] Alternatively, in step 43, dRy may be set to the smaller of the absolute values ​​of AD[WL] and dAD[EL], and the correction values ​​may be calculated by multiplying the difference value ΔAD of each electrode by the correction coefficient k15 for the electrode with the smaller absolute value of dAD[WL] and dAD[EL], and by the correction coefficient 1 / (k15).

[0190] If dRy=0 is determined in step S45, the correction coefficient k is set to 1 and no correction is performed.

[0191] In step S55, the positional misalignment dZ is set to the value with the smallest absolute value among dAD[NL], dAD[SL], dAD[EL], and dAD[WL]. The correction coefficient k16 is calculated for the electrode corresponding to this value, and the correction values ​​for the other electrodes are also corrected using the same correction coefficient k16. For example, if dAD[NL] is the smallest, the correction coefficient k16 is calculated as k16 = (difference value ΔAD[NL] at the reference position / actual difference value ΔAD[NL]), and the correction coefficients k for electrodes SL, EL, and WL are also set to the same value k16.

[0192] In the above embodiment, the correction coefficient k16 value was determined for the electrode corresponding to the one with the smallest absolute value among dAD[NL], dAD[SL], dAD[EL], and dAD[WL]. However, the correction coefficient k may be determined for each electrode using the same calculation formula.

[0193] If it is determined that dZ=0 in step S56, the correction coefficient k is set to 1 and no correction is performed.

[0194] The above describes how to determine the correction values ​​for the lower electrodes NL, SL, EL, and WL. However, as in the case where the sensor unit 150 shown in Figure 6 is misaligned, the correction coefficients obtained for the lower electrodes NL, SL, EL, and WL are used as the correction coefficients for the upper electrodes corresponding to each electrode, in the case of the upper electrodes NU, SU, EU, and WU. This is because determining the correction coefficients for the lower electrodes results in larger absolute values ​​for ΔAD and dAD because they are closer to the metal member 11, allowing for more accurate measurement of the misalignment. The correction values ​​for the upper electrodes NU, SU, EU, and WU may also be determined using the same method as for the lower electrodes NL, SL, EL, and WL.

[0195] As a variation, correction values ​​may be calculated for all electrostatic sensors, and the difference value ΔAD for each electrostatic sensor may be corrected. Specifically, a correction coefficient k corresponding to each electrode is calculated from the ΔAD value at the reference position of each electrostatic sensor and the actual difference value (the difference value ΔAD measured after attachment to the metal member 11 when there are no objects to be detected in the surroundings), and the difference value ΔAD measured in the actual operating state is corrected for each electrode. The correction coefficient is the same as described above (difference value ΔAD at the reference position / actual difference value ΔAD), and is a value corresponding to the positional misalignment.

[0196] Furthermore, in this case, if there is a misalignment between the substrate and the sensor unit 150, it is possible to handle cases where both the misalignment shown in Figure 6 and the misalignment shown in Figure 7 occur.

[0197] <Detection of the object's position by the detection unit 133 (detection of which operating unit 210A is being touched)> The detection unit 133 detects the position of an object relative to the operation unit 21A based on the output of the detection circuit 120 and a plurality of correction values ​​calculated by the correction value calculation unit 132. As an example, the case in which an object such as a fingertip approaches or touches the northern operation unit 21AN of the operation unit 21A in Figure 1 will be described. When an object such as a fingertip approaches or touches the operation unit 21AN, the difference value ΔAD of electrode NU becomes greater than or equal to a predetermined threshold. In addition, the difference value ΔAD of the upper electrode NU becomes greater than or equal to a predetermined value compared to the difference value ΔAD of the lower electrode NL. Furthermore, the difference values ​​ΔAD of electrodes WU and EU are equivalent within a predetermined range, with the difference value ΔAD of electrode NU being the largest, followed by the difference values ​​ΔAD of electrodes WU and EU, and then the difference value ΔAD of electrode SU being the smallest. Therefore, one method for the detection unit 133 to detect which operating unit 210A the object is touching is to identify an upper electrode above a predetermined threshold, and if the difference value ΔAD of the lower electrode is smaller than that of the upper electrode by a predetermined value or more, and the difference values ​​ΔAD of the upper electrodes located on both sides of the identified electrode are each smaller than the difference value ΔAD of the identified electrode and are within a predetermined range, and furthermore, if the difference value ΔAD of the upper electrode facing the identified electrode is the smallest, then it is determined that the object is in contact with or approaching the operating unit 21A closest to the identified electrode. Note that the determination of proximity or contact of an object is the same as detecting whether the object is located within a predetermined range or at a predetermined position, and is included in the concept of position detection.

[0198] The ECU130 of the control unit then determines that a designated control unit 21A has been operated and outputs a signal indicating this to the outside.

[0199] <Effects> The detection device 100 includes an electrostatic sensor 110 placed on a core metal 10 having a metal member 11 to which a predetermined potential or a predetermined waveform potential is applied; a detection circuit 120 connected to the electrostatic sensor 110 and detecting the capacitance of the electrostatic sensor 110; a positional displacement calculation unit 131 that calculates the positional displacement of the electrostatic sensor 110 relative to the metal member 11, or a value corresponding to the positional displacement, based on the output of the detection circuit 120 in a non-proximity state where the object is not in close proximity to the metal member 11; a correction value calculation unit 132 that calculates a correction value corresponding to the positional displacement or value corresponding to the positional displacement calculated by the positional displacement calculation unit 131; and a detection unit 133 that detects the position of the object based on the output of the detection circuit 120 and the correction value calculated by the correction value calculation unit 132. By calculating the positional displacement of the electrostatic sensor 110 relative to the metal member 11, or a value corresponding to the positional displacement, the position of the object relative to the metal member 11 can be determined, taking into account the fluctuations in the parasitic capacitance of the electrostatic sensor 110 and the metal member 11 due to the positional displacement of the electrostatic sensor 110 relative to the metal member 11.

[0200] Therefore, a detection device 100 capable of detecting the position of an object with high precision can be provided.

[0201] As mentioned above, in this embodiment, the correction value is obtained by correcting the positional deviation of the difference value ΔAD measured at each electrode in the actual usage state, and is a predicted value of the difference value ΔAD that would be measured if the sensor unit 150 were placed at the reference position. However, if the difference value ΔAD measured in the actual usage state exceeds a threshold, and it is determined that the distance of the object to the metal member 11 has approached within a predetermined value, the threshold may be corrected before making the determination.

[0202] Furthermore, in this embodiment, the position of the object relative to the metal member 11 was determined by determining which operating unit 21A the object was in contact with or approaching; however, the absolute position of the object may also be determined.

[0203] Furthermore, the device may include multiple electrostatic sensors 110, with the detection circuit 120 connected to the multiple electrostatic sensors 110 and detecting the capacitance of each electrostatic sensor 110. The positional displacement calculation unit 131 calculates the positional displacement of the multiple electrostatic sensors 110 relative to the metal member 11 based on the output of the detection circuit 120 in a non-proximity state of the object. The correction value calculation unit 132 calculates multiple correction values ​​corresponding to the positional displacement of the multiple electrostatic sensors 110 calculated by the positional displacement calculation unit 131, or values ​​corresponding to the positional displacement. The detection unit 133 detects the position of the object relative to the metal member 11 based on the output of the detection circuit 120 and the multiple correction values ​​calculated by the correction value calculation unit 132. By calculating the positional displacement of the multiple electrostatic sensors 110 relative to the metal member 11, the position of the object relative to the metal member 11 can be determined by considering the fluctuations in the parasitic capacitance of the multiple electrostatic sensors 110 and the metal member 11. Therefore, in a configuration including multiple electrostatic sensors 110, a detection device 100 capable of detecting the position of an object relative to the metal member 11 with high accuracy can be provided. Furthermore, since the position of the object can be determined according to the output of multiple electrostatic sensors 110, it becomes possible to configure the system so that no electrostatic sensor 110 is placed directly below the operating unit 210A, thereby improving the flexibility of the placement of the electrostatic sensors 110.

[0204] Furthermore, the multiple electrostatic sensors 110 are arranged on the side surface 151a1 of the sensor unit 150, which can be operated by the object, and the sensor unit 150 is attached to the core metal 10, so that the multiple electrostatic sensors 110 are positioned on the core metal 10, and the sensor unit 150 determines the content of the operation performed by the object on the operating unit 21A positioned relative to the core metal 10 according to the position of the object relative to the metal member 11 detected by the detection unit 133. Even if the position of the sensor unit 150 relative to the core metal 10 is misaligned and the positions of the multiple electrostatic sensors 110 relative to the core metal 10 are misaligned, the output of the multiple electrostatic sensors 110 can be corrected according to the misalignment, so that a detection device 100 can be provided that can detect the position of the object with high precision according to the misalignment of the output of the multiple electrostatic sensors 110.

[0205] Furthermore, the sensor unit 150 extends in a first and second direction perpendicular to each other within the plane on which the metal member 11 extends, and the plurality of electrostatic sensors 110 include a first electrostatic sensor 110 located in the first direction and a second electrostatic sensor 110 located in the second direction, and the outer edge of the metal member 11 may be located within a range in which the detection circuit 120 can detect the capacitance between the first electrostatic sensor 110 and the second electrostatic sensor 110. When the positional relationship between the metal member 11 and the first electrostatic sensor 110 or the second electrostatic sensor 110 in the planar direction shifts, the output value of the first electrostatic sensor 110 or the second electrostatic sensor 110 changes, so that the positional shift of the first electrostatic sensor 110 or the second electrostatic sensor 110 relative to the metal member 11 can be detected (step S3 or step 13).

[0206] Furthermore, the sensor unit 150 extends in a first and second direction perpendicular to each other within the plane on which the metal member 11 extends, and its sides are located on one side and the other side in the first direction. The multiple electrostatic sensors 110 are located on one side and the other side in the first direction. The positional displacement calculation unit 131 calculates the difference in capacitance between the electrostatic sensor 110 on one side and the electrostatic sensor 110 on the other side based on the output of the detection circuit 120 in a non-proximity state of the object, and based on this difference, it may detect the rotational displacement of the electrostatic sensor 110 on one side and the electrostatic sensor 110 on the other side around a second axis (X-axis or Y-axis) extending in the second direction relative to the metal member 11. Based on the relationship between the capacitance of the electrostatic sensor 110 on one side and the capacitance of the electrostatic sensor 110 on the other side, the rotational displacement around the second axis can be detected (step S33 or step S34).

[0207] Furthermore, the sensor unit 150 extends in a first and second direction perpendicular to each other within the plane on which the metal member 11 extends, and the multiple electrostatic sensors 110 are located on one side and the other side in the first direction. The positional displacement calculation unit 131 may, based on the output of the detection circuit 120 in a non-proximity state of the object, detect the positional displacement of the electrostatic sensor 110 on one side and the electrostatic sensor 110 on the other side in a third direction perpendicular to the first and second directions relative to the metal member 11 if both the capacitance of the electrostatic sensor 110 on one side and the electrostatic sensor 110 on the other side are above a predetermined threshold. Based on the outputs of the multiple electrostatic sensors 110, the positional displacement in the Z direction can be calculated (step S55).

[0208] Furthermore, an operation panel 210 is attached to the core metal 10, which has a projection 214 with an operation section 21A on its upper surface, and the sensor unit 150 is placed inside the projection 214. This makes it easy to place the electrostatic sensor inside the operation panel 210.

[0209] Furthermore, the first electrostatic sensor 110 and the second electrostatic sensor 110 are formed in a planar manner along the side surface 151a1 of the sensor unit 150. This allows for improved detection capabilities compared to arranging them as wires.

[0210] Furthermore, since the multiple electrostatic sensors 110 are arranged on the side surface of the sensor unit 150 along a third direction (Z-axis direction) perpendicular to the first and second directions, it is possible to determine whether the object is located above the upper surface 151a2 of the sensor unit 150 or opposite the side surface 151a1.

[0211] Furthermore, since the correction value is obtained using the lower electrostatic sensor 110, which is closer to the metal component 11, the value changes significantly with the deviation, and this can be used to improve accuracy.

[0212] Furthermore, since a temperature sensor 140 formed by a thermistor is provided to set the baseline of the electrostatic sensor 110, it is less susceptible to the effects of positional misalignment.

[0213] Furthermore, when the operating unit 200 is not in operation, the positional deviation calculation unit 131 calculates the positional deviation of the electrostatic sensor 110 relative to the metal member 11, or a value corresponding to the positional deviation. Therefore, the correction coefficient can be changed even after the vehicle, including the operating unit, is handed over to the user. Thus, even if a positional deviation occurs while the user is using the vehicle, it can be corrected in subsequent detections.

[0214] Although exemplary embodiments of the detection device and operating unit of this disclosure have been described above, this disclosure is not limited to the specifically disclosed embodiments, and various modifications and changes are possible without departing from the scope of the claims. [Explanation of symbols]

[0215] 100 detection device 110 Electrostatic Sensor 120 Detection Circuit 130 ECU 131 Positional deviation calculation unit 132 Correction Value Calculation Unit 133 Detection unit 134 memory

Claims

1. An electrostatic sensor is placed on a holding member having a conductor to which a predetermined potential or a predetermined waveform potential is applied, A detection circuit connected to the electrostatic sensor and detecting the capacitance of the electrostatic sensor, A positional deviation calculation unit calculates the positional deviation of the electrostatic sensor relative to the conductor, or a value corresponding to the positional deviation, based on the output of the detection circuit in a non-proximity state where the object is not in close proximity to the conductor. A correction value calculation unit calculates a correction value corresponding to the positional deviation or a value corresponding to the positional deviation calculated by the positional deviation calculation unit, A detection unit that detects the position of an object based on the output of the detection circuit and the correction value calculated by the correction value calculation unit. A detection device that includes this.

2. The above-mentioned electrostatic sensors include a plurality of them, The detection circuit is connected to the plurality of electrostatic sensors and detects the capacitance of each electrostatic sensor. The positional displacement calculation unit calculates the positional displacement of the plurality of electrostatic sensors relative to the conductor based on the output of the detection circuit in the non-proximity state of the object, The correction value calculation unit calculates a plurality of correction values ​​corresponding to the positional deviations of the plurality of electrostatic sensors calculated by the positional deviation calculation unit, or values ​​corresponding to the positional deviations. The detection device according to claim 1, wherein the detection unit detects the position of an object relative to the conductor based on the output of the detection circuit and the plurality of correction values ​​calculated by the correction value calculation unit.

3. The plurality of electrostatic sensors are arranged on the side of a sensor unit that can be operated by the object, By attaching the sensor unit to the holding member, the plurality of electrostatic sensors are arranged on the holding member. The detection device according to claim 2, wherein the sensor unit determines the content of the operation performed by the object according to the position of the object relative to the conductor detected by the detection unit.

4. The sensor unit extends in a plane in which the conductor extends, in a first direction and a second direction which are perpendicular to each other. The plurality of electrostatic sensors include a first electrostatic sensor located in the first direction and a second electrostatic sensor located in the second direction. The detection device according to claim 3, wherein the outer edge of the conductor is located within a range in which the detection circuit can detect the capacitance between the first electrostatic sensor and the second electrostatic sensor.

5. The sensor unit extends in a plane in which the conductor extends, in a first direction and a second direction which are perpendicular to each other. The aforementioned side surfaces are located on one side and the other side in the first direction, The plurality of electrostatic sensors are located on one side and the other side in the first direction, The detection device according to claim 3, wherein the positional displacement calculation unit calculates the difference in capacitance between the electrostatic sensor on one side and the electrostatic sensor on the other side based on the output of the detection circuit in the non-proximity state of the object, and detects the rotational positional displacement of the electrostatic sensor on one side and the electrostatic sensor on the other side around a second axis extending in the second direction with respect to the conductor, based on the difference.

6. The sensor unit extends in a plane in which the conductor extends, in a first direction and a second direction which are perpendicular to each other. The aforementioned side surfaces are located on one side and the other side in the first direction, The plurality of electrostatic sensors are located on one side and the other side in the first direction, The detection device according to claim 3, wherein the positional displacement calculation unit detects a positional displacement in a third direction perpendicular to the first and second directions with respect to the conductor between the electrostatic sensor on one side and the electrostatic sensor on the other side, based on the output of the detection circuit in the non-proximity state of the object, when both the capacitance of the electrostatic sensor on one side and the electrostatic sensor on the other side are above a predetermined threshold.

7. An operating panel having a protruding portion with an operating section on its upper surface is attached to the holding member. The detection device according to claim 3, characterized in that the sensor unit is arranged within the protruding portion.

8. The detection device according to claim 4, characterized in that the first electrostatic sensor and the second electrostatic sensor are formed in a planar shape along the side surface of the sensor unit.

9. The detection device according to claim 4, characterized in that the plurality of electrostatic sensors are arranged on the side surface of the sensor unit along a third direction perpendicular to the first and second directions.

10. The detection device according to claim 9, characterized in that the correction value calculation unit obtains the correction value using an electrostatic sensor that is close to a conductor.

11. The detection device according to claim 1, characterized in that a thermistor is provided to set the baseline of the electrostatic sensor.

12. An operating unit equipped with the detection device described in claim 1, wherein when the operating unit is not being operated, the positional displacement calculation unit calculates the positional displacement of the electrostatic sensor relative to the conductor, or a value corresponding to the positional displacement.

Images