Sensors and electronic devices

Abstract

To provide sensors and electronic devices that enable improved detection accuracy. [Solution] According to the embodiment, the sensor includes an element unit and a control unit. The element unit includes a base body including a base surface, a fixed part fixed to the base surface, a movable part supported by the fixed part, and first and second drive electrodes and first to fourth electrodes fixed to the base surface. The control unit performs a first operation and a detection operation. The first operation includes a vibration operation and a voltage setting operation. In the vibration operation, the control unit applies a first drive voltage between the movable part and the first drive electrode, and applies a second drive voltage between the movable part and the second drive electrode to vibrate the movable part and discretely change at least one of the first and second drive voltages. In the voltage setting operation, the control unit changes the first to fourth voltages between the first to fourth electrodes based on the vibration state of the movable part. In the detection operation, the control unit detects an external force using the first to fourth voltages.

Description

Technical Field

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[0001] Embodiments of the present invention relate to sensors and electronic devices.

Background Art

[0002] For example, there are sensors using MEMS (Micro Electro Mechanical Systems) elements etc. In sensors, improvement in accuracy is desired.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Embodiments provide a sensor and an electronic device capable of improving detection accuracy.

Means for Solving the Problems

[0005] According to the embodiment, the sensor includes an element section and a control section. The element section includes a substrate including a base surface, a fixed section fixed to the base surface, a movable section supported by the fixed section, the movable section having a gap between the base surface and the movable section, a first drive electrode fixed to the base surface and facing the movable section, a second drive electrode fixed to the base surface and facing the movable section, a first electrode fixed to the base surface and facing the movable section, a second electrode fixed to the base surface and facing the movable section, a third electrode fixed to the base surface and facing the movable section, and a fourth electrode fixed to the base surface and facing the movable section. The first drive direction from the fixed section to the first drive electrode is along the base surface. The second drive direction from the fixed section to the second drive electrode is along the base surface and intersects the first drive direction. The first electrode direction from the fixed section to the first electrode is along the base surface. The direction of the second electrode from the fixed portion to the second electrode follows the base surface and intersects the direction of the first electrode. The direction of the third electrode from the fixed portion to the third electrode follows the base surface and intersects the direction of the first electrode. The direction of the fourth electrode from the fixed portion to the fourth electrode follows the base surface and intersects the direction of the first electrode and the direction of the third electrode. The control unit is configured to perform a first operation and a detection operation. The first operation includes a vibration operation and a voltage setting operation. In the vibration operation, the control unit is configured to apply a first drive voltage between the movable portion and the first drive electrode, and a second drive voltage between the movable portion and the second drive electrode, causing the movable portion to vibrate along the base surface, and to discretely change at least one of the first drive voltage and the second drive voltage. In the voltage setting operation, the control unit is configured to change at least one of the following based on the vibration state of the movable part in the vibration operation: the first voltage between the movable part and the first electrode, the second voltage between the movable part and the second electrode, the third voltage between the movable part and the third electrode, and the fourth voltage between the movable part and the fourth electrode. In the detection operation, the control unit is configured to detect the external force applied to the element using the first voltage, second voltage, third voltage, and fourth voltage set in the voltage setting operation. [Brief explanation of the drawing]

[0006] [Figure 1] Figure 1 is a schematic diagram illustrating a sensor according to the first embodiment. [Figure 2] Figures 2(a) and 2(b) are schematic diagrams illustrating a part of the sensor according to the first embodiment. [Figure 3] Figure 3 is a schematic diagram illustrating the operation of the sensor in the first embodiment. [Figure 4] Figure 4 is a schematic diagram illustrating an electronic device according to the second embodiment. [Figure 5] Figures 5(a) to 5(g) are schematic diagrams illustrating applications of the electronic device according to the embodiment. [Figure 6] Figures 6(a) and 6(b) are schematic diagrams illustrating applications of the sensor according to the embodiment. [Modes for carrying out the invention]

[0007] The embodiments of the present invention will be described below with reference to the drawings. Drawings are schematic or conceptual, and the relationships between the thickness and width of each part, as well as the ratios of the sizes of different parts, are not necessarily identical to those of reality. Even when representing the same part, the dimensions and ratios may be depicted differently in different drawings. In this specification and in each figure, elements similar to those described above are denoted by the same reference numerals with respect to previously shown figures, and detailed explanations are omitted as appropriate.

[0008] (First Embodiment) Figure 1 is a schematic diagram illustrating a sensor according to the first embodiment. Figures 2(a) and 2(b) are schematic diagrams illustrating a part of the sensor according to the first embodiment. Figure 2(a) is a plan view. Figure 2(b) is a cross-sectional view taken along the line A1-A2 in Figure 2(a).

[0009] As shown in Figures 1, 2(a), and 2(b), the sensor 110 according to this embodiment includes an element unit 10E and a control unit 70.

[0010] As shown in Figures 2(a) and 2(b), the element portion 10E includes a base body 10s, a fixed portion 10F, and a movable portion 10M. As shown in Figure 2(b), the base body 10s includes a base surface 10f. The fixed portion 10F is fixed to the base surface 10f. The base surface 10f may be the upper surface of the base body 10s.

[0011] The movable part 10M is supported by the fixed part 10F. A gap G1 is provided between the base surface 10f and the movable part 10M.

[0012] The direction perpendicular to the base surface 10f is defined as the Z-axis direction. One direction perpendicular to the Z-axis direction is defined as the X-axis direction. The directions perpendicular to both the Z-axis and X-axis directions are defined as the Y-axis direction. The base surface 10f lies along the XY plane.

[0013] The element section 10E includes a first drive electrode 31, a second drive electrode 32, a first electrode 51, a second electrode 52, a third electrode 53, and a fourth electrode 54. The first drive electrode 31 is fixed to the base surface 10f and faces the movable part 10M. The second drive electrode 32 is fixed to the base surface 10f and faces the movable part 10M. The first electrode 51 is fixed to the base surface 10f and faces the movable part 10M. The second electrode 52 is fixed to the base surface 10f and faces the movable part 10M. The third electrode 53 is fixed to the base surface 10f and faces the movable part 10M. The fourth electrode 54 is fixed to the base surface 10f and faces the movable part 10M.

[0014] In this example, the movable part 10M includes an annular portion 10n. The annular portion 10n is located around the fixed portion 10F along the base surface 10f. The first drive electrode 31, the second drive electrode 32, the first electrode 51, the second electrode 52, the third electrode 53, and the fourth electrode 54 face the annular portion 10n. In this example, the movable part 10M includes multiple annular portions 10n. The multiple annular portions 10n are concentric around the fixed portion 10F.

[0015] For example, the fixed part 10F includes the fixed part center 10c on the base surface 10f. The movable part 10M includes the radiation part 10x. The radiation part 10x extends along the radiation direction. The radiation direction passes through the fixed part center 10c and is along the base surface 10f. The plurality of annular parts 10n are connected to each other by the radiation part 10x.

[0016] In this example, the first drive electrode 31 faces a part of the annular part 10n of the movable part 10M. The second drive electrode 32 faces another part of the annular part 10n. The first electrode 51 faces another part of the annular part 10n. The second electrode 52 faces another part of the annular part 10n. The third electrode 53 faces another part of the annular part 10n. The fourth electrode 54 faces another part of the annular part 10n.

[0017] The first drive direction Dd1 from the fixed part 10F (e.g., the fixed part center 10c) to the first drive electrode 31 is along the base surface 10f (see Fig. 2(a)). The second drive direction Dd2 from the fixed part 10F (e.g., the fixed part center 10c) to the second drive electrode 32 is along the base surface 10f and intersects the first drive direction Dd1.

[0018] The first electrode direction De1 from the fixed part 10F (e.g., the fixed part center 10c) to the first electrode 51 is along the base surface 10f. The second electrode direction De2 from the fixed part 10F (e.g., the fixed part center 10c) to the second electrode 52 is along the base surface 10f and intersects the first electrode direction De1. The third electrode direction De3 from the fixed part 10F (e.g., the fixed part center 10c) to the third electrode 53 is along the base surface 10f and intersects the first electrode direction De1. The fourth electrode direction De4 from the fixed part 10F (e.g., the fixed part center 10c) to the fourth electrode 54 is along the base surface 10f and intersects the first electrode direction De1 and the third electrode direction De3.

[0019] In this example, the element part 10E further includes the first counter electrode 41 and the second counter electrode 42. The first counter electrode 41 is fixed to the base surface 10f and faces the movable part 10M. The second counter electrode 42 is fixed to the base surface 10f and faces the movable part 10M. For example, the first counter electrode 41 faces another part of the annular part 10n. The second counter electrode 42 faces another part of the annular part 10n.

[0020] The first facing direction Ds1 from the fixing portion 10F (e.g., the center 10c of the fixing portion) to the first facing electrode 41 is along the substrate surface 10f. The second facing direction Ds2 from the fixing portion 10F (e.g., the center 10c of the fixing portion) to the second facing electrode 42 is along the substrate surface 10f and intersects the first facing direction Ds1.

[0021] The direction in which each of the above various electrodes faces the movable portion 10M is along the radial direction passing through the center 10c of the fixing portion.

[0022] As shown in FIG. 1, the control unit 70 is electrically connected to the above various electrodes. In one example, the control unit 70 may include a drive circuit 71, a detection circuit 72, a control circuit 73, and the like.

[0023] The drive circuit 71 is configured to apply a first drive voltage Vd1 between the first drive electrode 31 and the movable portion 10M. The drive circuit 71 is configured to apply a second drive voltage Vd2 between the second drive electrode 32 and the movable portion 10M. These drive voltages are, for example, alternating current. When these drive voltages are applied, the movable portion 10M vibrates. The direction of vibration is along the substrate surface 10f.

[0024] The detection circuit 72 is configured to detect, for example, a first signal Vs1 between the movable portion 10M and the first facing electrode 41. The detection circuit 72 is configured to detect, for example, a second signal Vs2 between the movable portion 10M and the second facing electrode 42. By detecting these signals, the vibration state (e.g., the vibration direction) of the movable portion 10M is detected.

[0025] For example, when the movable part 10M vibrates due to the above-mentioned drive voltage, if an external force is applied to the element part 10E, the vibration state changes. For example, the direction of vibration when an external force is applied changes from the direction of vibration when no external force is applied. This change is thought to be based on, for example, the Coriolis force. By detecting the change in vibration direction As1, for example, the angular velocity of the external force is detected. The control circuit 73 is configured to output a detection signal Sig0 based on the change in vibration direction As1. The detection signal Sig0 includes information about the angular velocity of the external force. The sensor 110 is, for example, an angular velocity sensor.

[0026] The first counter electrode 41 and the second counter electrode 42 may function, for example, as detection electrodes.

[0027] As described above, the element section 10E includes a first electrode 51, a second electrode 52, a third electrode 53, and a fourth electrode 54. These electrodes may function, for example, as electrodes for adjusting the vibration characteristics of the movable part 10M. These electrodes may function, for example, as electrodes for calibrating the vibration characteristics of the movable part 10M.

[0028] The control unit 70 may be configured to perform the following first operation and detection operation. The first operation includes vibration operation and voltage setting operation.

[0029] During vibration operation, the control unit 70 applies a first drive voltage Vd1 between the movable part 10M and the first drive electrode 31, and a second drive voltage Vd2 between the movable part 10M and the second drive electrode 32, causing the movable part 10M to vibrate along the base surface 10f. During this vibration operation, the control unit 70 is configured to discretely change at least one of the first drive voltage Vd1 and the second drive voltage Vd2.

[0030] By discretely changing at least one of the first drive voltage Vd1 and the second drive voltage Vd2, the vibration angle θ between the vibration direction Dx of the movable part 10M (see Figure 2(a)) and the reference direction along the base surface 10f changes discretely. The reference direction is arbitrary and may be, for example, the X-axis direction.

[0031] In the voltage setting operation, the control unit 70 is configured to change at least one of the following voltages based on the vibration state of the movable part 10M during vibration operation (e.g., vibration direction Dx): a first voltage Vp1 between the movable part 10M and the first electrode 51, a second voltage Vp2 between the movable part 10M and the second electrode 52, a third voltage Vp3 between the movable part 10M and the third electrode 53, and a fourth voltage Vp4 between the movable part 10M and the fourth electrode 54. These voltages may correspond to, for example, bias voltages. The voltage setting operation corresponds to the bias voltage setting operation.

[0032] Through such vibration and voltage setting operations, the bias voltage is appropriately set. The first operation corresponds, for example, to a calibration operation.

[0033] In the detection operation, the control unit 70 is configured to detect the external force applied to the element unit 10E using the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 that were set in the voltage setting operation.

[0034] By combining this first operation (calibration operation) with the detection operation, detection with higher accuracy becomes possible. According to this embodiment, a sensor capable of improving detection accuracy can be provided.

[0035] For example, the vibration characteristics of the movable part 10M may be uneven due to non-uniformity during manufacturing. For example, the vibration characteristics of the movable part 10M may be asymmetrical in the direction within the XY plane. Such asymmetry is calibrated by the first operation.

[0036] In the first operation, the voltage setting operation includes, for example, changing at least one of the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 so that the asymmetry of the vibration state of the movable part 10M in the vibration operation is reduced.

[0037] For example, the movable part 10M has a first resonant frequency in a first direction D1 and a second resonant frequency in a second direction D2 (see Figure 2). The first direction D1 is one direction along the base surface 10f. The second direction D2 is along the base surface 10f and intersects with the first direction D1. The second direction D2 may be perpendicular to the first direction D1. For example, these resonant frequencies may not coincide due to non-uniformity during manufacturing. In this embodiment, at least one of the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 is modified so that the difference between the first and second resonant frequencies is reduced.

[0038] As described above, in this embodiment, at least one of the first drive voltage Vd1 and the second drive voltage Vd2 is discretely changed. The vibration angle θ of the vibration direction Dx of the movable part 10M changes discretely. As a result, the movable part 10M vibrates at one vibration angle θ during one period. This allows for a more accurate derivation of the calibration voltage during one period.

[0039] For example, in a reference example where the drive voltage is continuously changed, the vibration angle θ changes continuously over time. In this case, the vibration angle θ is constantly changing. Therefore, it is difficult to accurately derive the voltage for calibration.

[0040] In this embodiment, at least one of the first drive voltage Vd1 and the second drive voltage Vd2 is discretely changed. This allows for a more accurate derivation of the calibration voltage over a single period.

[0041] At least one of the above-mentioned first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 may be 0. The voltage setting operation may include setting the voltage to 0 volts. Changing at least one of the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 may include setting at least one of the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 to 0 volts.

[0042] As already explained, the vibration state of the movable part 10M is derived according to the detection results of the first signal Vs1 between the movable part 10M and the first counter electrode 41, and the second signal Vs2 between the movable part 10M and the second counter electrode 42.

[0043] The control unit 70 may be configured to repeatedly perform a set including a first operation (calibration operation) and a detection operation. For example, the first operation may be performed before each of a plurality of detection operations using the sensor 110. High-precision detection results can be obtained. In this embodiment, the control unit 70 may be configured to perform the first operation when the power supply of the control unit 70 is turned on.

[0044] As described above, the detection operation includes vibrating the movable part 10M along the base surface 10f, detecting changes in the vibration state of the movable part 10M caused by an external force, and detecting the angular velocity of the external force. By performing the first operation described above before such a detection operation, a detection operation with high accuracy can be performed.

[0045] Figure 3 is a schematic diagram illustrating the operation of the sensor in the first embodiment. Figure 3 illustrates the vibration motion of the first operation. The horizontal axis in Figure 3 represents time tm. The vertical axis in Figure 3 represents the vibration angle θ of the movable part 10M.

[0046] As shown in Figure 3, in the first period T1, the vibration angle θ of the movable part 10M is the first vibration angle θ1. In the second period T2, the vibration angle θ of the movable part 10M is the second vibration angle θ2. In the i-th period Ti, the vibration angle θ of the movable part 10M is the i-th vibration angle θi, where "i" is an integer greater than or equal to 1.

[0047] During the i-th period Ti, the control unit 70 sets at least one of the first drive voltage Vd1 and the second drive voltage Vd2 so that an vibration of the i-th vibration angle θi is obtained.

[0048] Thus, in the first period T1 of the vibration operation, the vibration angle θ between the vibration direction of the movable part 10M and the reference direction along the base surface 10f is the first vibration angle θ1. In the second period T2 of the vibration operation, the vibration angle θ is the second vibration angle θ2.

[0049] As shown in Figure 3, the vibration angle θ is discretely changed between a minimum angle θa and a maximum angle θb. In the voltage setting operation, the control unit 70 is configured to change at least one of the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 so as to reduce the absolute value of the difference between the first resonant frequency and the second resonant frequency, based on the vibration state of the movable part 10M when the vibration angle θ is discretely changed between the minimum angle θa and the maximum angle θb during vibration operation.

[0050] For example, any of the above changes to at least one of the first voltage Vp1, second voltage Vp2, third voltage Vp3, and fourth voltage Vp4 may be made by curve fitting of the characteristics of the vibration state of the movable part 10M when the vibration angle θ changes discretely.

[0051] For example, the absolute value of the difference between the first and second resonant frequencies after the first operation (calibration operation) is smaller than the absolute value of the difference between the first and second resonant frequencies before the first operation (calibration operation).

[0052] The difference between the minimum angle θa and the maximum angle θb corresponds to the amount (range) of change in the vibration angle θ. In the embodiment, it is preferable that the amount of change in the vibration angle is 90 degrees or more during vibration operation. A larger amount of change in the vibration angle allows for a more accurate understanding of the vibration characteristics of the movable part 10M. This enables a more precise configuration.

[0053] In vibrational motion, the amount of change in the vibration angle θ may be 170 degrees or more. In vibrational motion, the amount of change in the vibration angle θ may be 175 degrees or more and 180 degrees or less.

[0054] In vibration operation, it is preferable that the number of changes in the vibration angle θ be 8 or more. This allows for more accurate calibration. In vibration operation, the number of changes in the vibration angle θ may be 12 or more.

[0055] As shown in Figure 3, the vibration motion may include discretely increasing the vibration angle θ as time tm progresses. In the embodiment, the vibration motion may include discretely increasing or decreasing the vibration angle θ as time tm progresses.

[0056] The i-th period Ti can be, for example, 1 ms or more and 60 seconds or less. The first period T1 can be, for example, 1 ms or more and 60 seconds or less. The second period T2 can be, for example, 1 ms or more and 60 seconds or less.

[0057] In this embodiment, the second drive direction Dd2 may be substantially perpendicular to the first drive direction Dd1. A fixed portion 10F (e.g., fixed portion center 10c) may be present between the first opposing electrode 41 and the first drive electrode 31. A fixed portion 10F (e.g., fixed portion center 10c) may be present between the second opposing electrode 42 and the second drive electrode 32. The first electrode direction De1 may be inclined with respect to the first drive direction Dd1. The second electrode direction De2 may be inclined with respect to the first electrode direction De1. The third electrode direction De3 may be substantially perpendicular to the first electrode direction De1. The fourth electrode direction De4 may be substantially perpendicular to the third electrode direction De3.

[0058] (Second Embodiment) The second embodiment relates to an electronic device. Figure 4 is a schematic diagram illustrating an electronic device according to the second embodiment. As shown in Figure 4, the electronic device 310 according to the embodiment includes a sensor according to the first embodiment (e.g., sensor 110) and a circuit control unit 170. The circuit control unit 170 can control a circuit 180 based on a signal S1 obtained from the sensor. The circuit 180 is, for example, a control circuit for a drive device 185. According to the embodiment, for example, a circuit 180 for controlling a drive device 185 can be controlled with high precision.

[0059] As shown in Figure 4, the sensor system 210 according to the embodiment includes a sensor according to the first embodiment (for example, sensor 110) and a member to be detected 81. Sensor 110 is fixed to the member to be detected 81. Sensor 110 can detect signals from the member to be detected 81.

[0060] Figures 5(a) to 5(g) are schematic diagrams illustrating applications of the electronic device according to the embodiment. As shown in Figure 5(a), the electronic device 310 may be at least part of a robot. As shown in Figure 5(b), the electronic device 310 may be at least part of a machine robot installed in a manufacturing plant or the like. As shown in Figure 5(c), the electronic device 310 may be at least part of an automated guided vehicle in a factory or the like. As shown in Figure 5(d), the electronic device 310 may be at least part of a drone (unmanned aerial vehicle). As shown in Figure 5(e), the electronic device 310 may be at least part of an airplane. As shown in Figure 5(f), the electronic device 310 may be at least part of a ship. As shown in Figure 8(g), the electronic device 310 may be at least part of an automobile. The electronic device 310 may include, for example, at least one of a robot and a mobile body.

[0061] Figures 6(a) and 6(b) are schematic diagrams illustrating applications of the sensor according to the embodiment. As shown in Figure 6(a), the sensor 430 according to the embodiment includes the sensor according to the first embodiment and a transmitting / receiving unit 420. In the example in Figure 6(a), the sensor 110 is depicted as the sensor. The transmitting / receiving unit 420 can transmit the signal obtained from the sensor 110 by, for example, at least one of wireless and wired methods. The sensor 430 is installed, for example, on a slope surface 410 such as a road 400. The sensor 430 can monitor the state of, for example, a facility (e.g., infrastructure). The sensor 430 may be, for example, a state monitoring device.

[0062] For example, the sensor 430 detects changes in the condition of the slope surface 410 of the road 400 with high accuracy. Changes in the condition of the slope surface 410 include, for example, changes in the inclination angle and changes in the vibration state. The signal (inspection result) obtained from the sensor 110 is transmitted by the transmitting / receiving unit 420. The condition of the facility (e.g., infrastructure) can be monitored, for example, continuously.

[0063] As shown in Figure 6(b), the sensor 430 is installed, for example, on a part of a bridge 460. The bridge 460 is built over a river 470. For example, the bridge 460 includes at least one of a main girder 450 and a pier 440. The sensor 430 is installed on at least one of the main girder 450 and the pier 440. For example, the angle of at least one of the main girder 450 and the pier 440 may change due to deterioration or other reasons. For example, the vibration state may change in at least one of the main girder 450 and the pier 440. The sensor 430 can detect these changes with high accuracy. The detection results can be transmitted to any location by the transmitting / receiving unit 420. Anomalies can be effectively detected.

[0064] The embodiments may include the following technical proposals. (Technical proposal 1) The element part, Control unit and Equipped with, The aforementioned element section is A substrate including a substrate surface, A fixing part fixed to the base surface, A movable part supported by the fixed part, wherein a gap is provided between the base surface and the movable part, A first drive electrode fixed to the base surface and facing the movable part, A second drive electrode fixed to the base surface and facing the movable part, A first electrode fixed to the base surface and facing the movable part, A second electrode fixed to the base surface and facing the movable part, A third electrode fixed to the base surface and facing the movable part, A fourth electrode fixed to the base surface and facing the movable part, Includes, The first driving direction from the fixed portion to the first driving electrode is along the substrate surface, The second driving direction from the fixed portion to the second driving electrode follows the substrate surface and intersects with the first driving direction. The direction from the fixed portion to the first electrode is along the substrate surface, The direction from the fixed portion to the second electrode is along the substrate surface and intersects with the direction of the first electrode. The direction from the fixed portion to the third electrode is along the substrate surface and intersects with the direction of the first electrode. The direction from the fixed portion to the fourth electrode is along the substrate surface and intersects with the direction of the first electrode and the direction of the third electrode. The control unit is configured to perform the first operation and the detection operation. The first operation includes vibration operation and voltage setting operation, In the vibration operation, the control unit is configured to apply a first drive voltage between the movable part and the first drive electrode, and a second drive voltage between the movable part and the second drive electrode, causing the movable part to vibrate along the base surface, and to discretely change at least one of the first drive voltage and the second drive voltage. In the voltage setting operation, the control unit is configured to change at least one of the following based on the vibration state of the movable part in the vibration operation: the first voltage between the movable part and the first electrode, the second voltage between the movable part and the second electrode, the third voltage between the movable part and the third electrode, and the fourth voltage between the movable part and the fourth electrode. In the detection operation, the control unit is configured to detect the external force applied to the element using the first voltage, second voltage, third voltage, and fourth voltage set in the voltage setting operation.

[0065] (Technical proposal 2) The sensor according to Technical Proposal 1, wherein the detection operation includes vibrating the movable part along the base surface, detecting a change in the vibration state of the movable part caused by the external force, and detecting the angular velocity of the external force.

[0066] (Technical proposal 3) The aforementioned element section is A first counter electrode fixed to the base surface and facing the movable part, A second opposing electrode fixed to the base surface and facing the movable part, Includes, The first opposing direction from the fixed portion to the first opposing electrode is along the substrate surface, The second opposing direction from the fixed portion to the second opposing electrode follows the substrate surface and intersects with the first opposing direction. The vibration state of the movable part is derived according to the detection results of a first signal between the movable part and the first counter electrode, and a second signal between the movable part and the second counter electrode, as described in Technical Proposal 2.

[0067] (Technical proposal 4) The sensor according to any one of Technical Proposals 1 to 3, wherein the voltage setting operation includes changing at least one of the first voltage, the second electrode, the third voltage, and the fourth voltage so that the asymmetry of the vibration state of the movable part in the vibration operation is reduced.

[0068] (Technical proposal 5) The sensor according to any one of Technical Proposals 1 to 3, wherein the vibration angle between the vibration direction of the movable part and the reference direction along the base surface is discretely changed by discretely changing at least one of the first drive voltage and the second drive voltage in the vibration operation.

[0069] (Technical proposal 6) The movable part has a first resonant frequency in a first direction along the base surface and a second resonant frequency in a second direction along the base surface, the second direction intersects with the first direction, The sensor according to Technical Proposal 5, wherein in the voltage setting operation, the control unit is configured to change at least one of the first voltage, second voltage, third voltage, and fourth voltage based on the vibration state of the movable part when the vibration angle changes discretely in the vibration operation, such that the absolute value of the difference between the first resonant frequency and the second resonant frequency becomes smaller.

[0070] (Technical proposal 7) The sensor according to Technical Proposal 5 or 6, wherein the vibration operation includes discretely increasing or decreasing the vibration angle over time.

[0071] (Technical proposal 8) The sensor according to any one of Technical Proposals 5 to 7, wherein in the vibration operation, the amount of change in the vibration angle is 90 degrees or more.

[0072] (Technical proposal 9) The sensor according to any one of Technical Proposals 5 to 7, wherein in the vibration operation, the amount of change in the vibration angle is 170 degrees or more.

[0073] (Technical proposal 10) The sensor according to any one of Technical Proposals 5 to 7, wherein in the vibration operation, the amount of change in the vibration angle is 175 degrees or more and 180 degrees or less.

[0074] (Technical proposal 11) The sensor according to any one of Technical Proposals 5 to 7, wherein the number of changes in the vibration angle during the vibration operation is 8 or more.

[0075] (Technical proposal 12) The sensor according to any one of Technical Proposals 5 to 7, wherein the number of changes in the vibration angle during the vibration operation is 12 or more.

[0076] (Technical proposal 13) During the first period of the vibration operation, the vibration angle is the first vibration angle. The sensor according to any one of Technical Proposals 5 to 12, wherein, during the second period of the vibration operation, the vibration angle is the second vibration angle.

[0077] (Technical proposal 14) The sensor described in Technical Proposal 13, wherein the first period is 10 ms or more and 60 s or less.

[0078] (Technical proposal 15) The control unit is configured to repeatedly perform a set including the first operation and the detection operation, as described in any one of Technical Proposals 1 to 14.

[0079] (Technical proposal 16) The control unit is configured to perform the first operation when the power to the control unit is turned on, as described in any one of Technical Proposals 1 to 15.

[0080] (Technical proposal 17) The movable part includes an annular portion, The annular portion is located along the base surface and around the fixing portion. The sensor according to any one of Technical Proposals 1 to 16, wherein the first drive electrode, the second drive electrode, the first electrode, the second electrode, the third electrode, and the fourth electrode face the annular portion.

[0081] (Technical proposal 18) The movable part includes a plurality of the annular parts, The sensor according to technical proposal 17, wherein the plurality of annular portions are concentric with respect to the fixed portion.

[0082] (Technical proposal 19) The fixing portion includes the fixing portion center on the base surface, The movable part includes a radiating part, The aforementioned radiating portion extends along the radial direction, The aforementioned radial direction passes through the center of the fixed part and along the surface of the base body, The sensor according to technical proposal 18, wherein the plurality of annular portions are connected to each other by the radiating portion.

[0083] (Technical proposal 20) A sensor described in any one of Technical Proposals 1 to 19, A circuit control unit capable of controlling the circuit based on the signal obtained from the sensor, An electronic device.

[0084] According to the embodiment, sensors and electronic devices capable of improving detection accuracy can be provided.

[0085] The embodiments of the present invention have been described above with reference to specific examples. However, the present invention is not limited to these specific examples. For example, the specific configuration of each element included in the sensor, such as the element part, substrate, fixed part, movable part, fixed electrode, and control unit, is included within the scope of the present invention as long as it can be implemented in the same way and similar effects can be obtained by appropriately selecting from the range known to those skilled in the art.

[0086] Furthermore, combinations of two or more elements from any of the specific examples, to the extent technically feasible, are also included within the scope of the present invention, insofar as they encompass the gist of the invention.

[0087] Furthermore, all sensors and electronic devices that a person skilled in the art can implement by appropriately modifying the design based on the sensors and electronic devices described above as embodiments of the present invention also fall within the scope of the present invention, insofar as they encompass the gist of the present invention.

[0088] Furthermore, within the scope of the concept of the present invention, a person skilled in the art could conceive of various modifications and alterations, and it is understood that such modifications and alterations also fall within the scope of the present invention.

[0089] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0090] 10E: Element part, 10F: Fixed part, 10M: Movable part, 10c: Fixed part center, 10f: Base surface, 10n: Annular part, 10s: Base, 10x: Radiating part, 31, 32: First and second drive electrodes, 41, 42: First and second counter electrodes, 51-54: First to fourth electrodes, 70: Control unit, 71: Drive circuit, 72: Detection circuit, 73: Control circuit, 81: Detected object, 110: Sensor, 170: Circuit control unit, 180: Circuit, 185: Drive device, 210: Sensor system, 310: Electronic device, 400: Road, 410: Slope surface, 420: Transmitter / receiver unit, 430: Sensor, 440: Pier, 450: Main girder, 460: Bridge, 470: River, As1: Change, D1, D2: 1st, 2nd direction, Dd1, Dd2: 1st, 2nd driving direction, De1~De4: 1st~4th electrode direction, Ds1, Ds2: 1st, 2nd opposing direction, Dx: Vibration direction, G1: Gap, S1: Signal, Sig0: Detection signal, T1, T2: 1st, 2nd period, Ti: ith period, Vd1, Vd2: 1st, 2nd driving voltage, Vp1~Vp4: 1st~4th voltage, Vs1, Vs2: 1st, 2nd signal, tm: Time, θ: Vibration angle, θ1, θ2: 1st, 2nd vibration angle

Claims

1. The element part, Control unit and Equipped with, The aforementioned element section is A substrate including a substrate surface, A fixing part fixed to the base surface, A movable part supported by the fixed part, wherein a gap is provided between the base surface and the movable part, A first drive electrode fixed to the base surface and facing the movable part, A second drive electrode fixed to the base surface and facing the movable part, A first electrode fixed to the base surface and facing the movable part, A second electrode fixed to the base surface and facing the movable part, A third electrode fixed to the base surface and facing the movable part, A fourth electrode fixed to the base surface and facing the movable part, Includes, The first driving direction from the fixed portion to the first driving electrode is along the substrate surface, The second driving direction from the fixed portion to the second driving electrode follows the surface of the base body and intersects with the first driving direction. The direction from the fixed portion to the first electrode is along the substrate surface, The direction from the fixed portion to the second electrode is along the substrate surface and intersects with the direction of the first electrode. The direction from the fixed portion to the third electrode is along the substrate surface and intersects with the direction of the first electrode. The direction from the fixed portion to the fourth electrode is along the substrate surface and intersects with the direction of the first electrode and the direction of the third electrode. The control unit is configured to perform the first operation and the detection operation. The first operation includes vibration operation and voltage setting operation, In the vibration operation, the control unit is configured to apply a first drive voltage between the movable part and the first drive electrode, and a second drive voltage between the movable part and the second drive electrode, causing the movable part to vibrate along the base surface, and to discretely change at least one of the first drive voltage and the second drive voltage. In the voltage setting operation, the control unit is configured to change at least one of the following based on the vibration state of the movable part in the vibration operation: the first voltage between the movable part and the first electrode, the second voltage between the movable part and the second electrode, the third voltage between the movable part and the third electrode, and the fourth voltage between the movable part and the fourth electrode. In the detection operation, the control unit is configured to detect the external force applied to the element using the first voltage, second voltage, third voltage, and fourth voltage set in the voltage setting operation.

2. The sensor according to claim 1, wherein the detection operation includes vibrating the movable part along the base surface, detecting a change in the vibration state of the movable part caused by the external force, and detecting the angular velocity of the external force.

3. The aforementioned element section is A first counter electrode fixed to the base surface and facing the movable part, A second opposing electrode fixed to the base surface and facing the movable part, Includes, The first opposing direction from the fixed portion to the first opposing electrode is along the substrate surface, The second opposing direction from the fixed portion to the second opposing electrode follows the substrate surface and intersects with the first opposing direction. The vibration state of the movable part is derived according to the detection result of a first signal between the movable part and the first counter electrode, and a second signal between the movable part and the second counter electrode, as described in claim 2.

4. The sensor according to any one of claims 1 to 3, wherein the voltage setting operation includes changing at least one of the first voltage, the second electrode, the third voltage, and the fourth voltage so that the asymmetry of the vibration state of the movable part in the vibration operation is reduced.

5. The sensor according to any one of claims 1 to 3, wherein the vibration angle between the vibration direction of the movable part and the reference direction along the base surface is discretely changed by discretely changing at least one of the first drive voltage and the second drive voltage in the vibration operation.

6. The sensor according to claim 5, wherein the vibration operation includes discretely increasing or decreasing the vibration angle over time.

7. The sensor according to any one of claims 1 to 3, wherein the control unit is configured to repeatedly perform a set including the first operation and the detection operation.

8. The movable part includes an annular portion, The annular portion is located along the base surface and around the fixing portion. The sensor according to any one of claims 1 to 3, wherein the first drive electrode, the second drive electrode, the first electrode, the second electrode, the third electrode, and the fourth electrode face the annular portion.

9. The movable part includes a plurality of the annular parts, The sensor according to claim 8, wherein the plurality of annular portions are concentric with respect to the fixed portion.

10. The sensor according to claim 1, A circuit control unit capable of controlling the circuit based on the signal obtained from the sensor, An electronic device.

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