Force detection device and conveying device

Abstract

To provide a force detection device that can provide reliability information indicating the reliability of external force information to be output.SOLUTION: A force detection device comprises: a structure that includes a deformation part that elastically deforms according to an external force; a plurality of detectors that detect displacement at a plurality of parts of the structure; and an operation unit that, on the basis of output from the plurality of detectors, generates and outputs external force information indicating the external force and reliability information indicating the reliability of the external force information. The operation unit generates a plurality of pieces of temperature change information each indicating a change of a parameter value having correlation with temperature on the basis of the output from the plurality of detectors, and generates the reliability information on the basis of the plurality of pieces of temperature change information.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a force detection device and a conveying device.

Background Art

[0002] Patent Document 1 describes a force sensor that detects an external force. The force sensor includes a base portion, a displacement portion that is displaced with respect to the base portion when receiving an external force, an elastic support portion that connects the base portion and the displacement portion, and a displacement detector that detects displacements at a plurality of locations of the displacement portion, and calculates information indicating an external force, a moment, and a thermal expansion component, respectively.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] A force detection device such as a force sensor is incorporated into a device such as a robot, for example, and the operation of the device can be controlled based on the external force information output by the force detection device. Therefore, when the external force information output by the force detection device is incorrect, the device whose operation is controlled according to the output may perform an unexpected operation.

[0005] An object of the present invention is to provide a force detection device capable of providing reliability information indicating the reliability of the output external force information.

Means for Solving the Problems

[0006] One aspect of the present invention relates to a force detection device, the force detection device including a structure including a deformation part that elastically deforms in response to an external force, a plurality of detectors that respectively detect displacements at a plurality of locations of the structure, and an arithmetic unit that generates and outputs external force information indicating the external force and reliability information indicating the reliability of the external force information based on the outputs of the plurality of detectors. The arithmetic unit generates a plurality of temperature change information respectively indicating changes in parameter values correlated with temperature based on the outputs of the plurality of detectors, and generates the reliability information based on the plurality of temperature change information.

Advantages of the Invention

[0007] According to the present invention, there is provided a force detection device capable of providing reliability information indicating the reliability of output external force information.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3A

Figure 3B

Figure 4A

Figure 4B

Figure 5

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims. Although a plurality of features are described in the embodiments, not all of these plurality of features are essential to the invention, and the plurality of features may be arbitrarily combined. Further, in the accompanying drawings, the same or similar configurations are denoted by the same reference numerals, and redundant descriptions are omitted.

[0010] In the accompanying drawings, directions are indicated by the XYZ coordinate system. The X direction, Y direction, and Z direction parallel to the X axis, Y axis, and Z axis respectively are directions orthogonal to each other.

[0011] FIG. 1 shows a schematic configuration example of a force detection device 100 according to the first embodiment. The force detection device 100 can be, for example, called a force sensor, a torque sensor, or a force / torque sensor according to the force and / or torque to be detected. Alternatively, the force detection device 100 may be called a detection device. The force detection device 100 can be configured to output external force information indicating an external force (force and / or torque) received by the force detection device 100 and reliability information indicating the reliability of the external force information. The force detection device 100 can include a structure ST including a deformation part 3 that elastically deforms according to an external force (force and / or torque), and a plurality of detectors DT that respectively detect displacements at a plurality of locations of the structure ST. The plurality of locations can be a plurality of locations where deformation of the deformation part 3 in a first direction (for example, the X direction) and deformation of the deformation part 3 in a second direction (for example, the Y direction) different from the first direction can be acquired based on the outputs of the plurality of detectors DT. The force detection device 100 also includes a force receiving part 2 that receives an external force, and the deformation part 3 can be configured to be deformed by the external force received by the force receiving part 2.

[0012] The force detection device 100 may also include a circuit board 6 that can be supported by the structure ST and / or the force receiving part 2. The force detection device 100 may also include an arithmetic unit 20 that generates and outputs external force information indicating the external force received by the force detection device 100 and reliability information indicating the reliability of the external force information based on the outputs of a plurality of detectors DT. On one side, the arithmetic unit 20 may constitute a part of the circuit board 6. On the other side, the circuit board 6 may function as a support member that supports the arithmetic unit 20. The circuit board 6 as a support member may be understood as a component of the structure ST. The plurality of detectors DT are arranged so as to be able to detect a plurality of displacement information for generating external force information indicating the external force received by the force detection device 100 and reliability information indicating the reliability of the external force information.

[0013] In addition to the deformed part 3, the structure ST may include a base part 1. The base part 1 may include, for example, a member having a frame shape or a cylindrical shape. The base part 1 may be connected to the force receiving part 2 via the deformed part 3. Each detector DT may include a scale 4 and a displacement detector 10. The scale 4 and the displacement detector 10 may be arranged to face each other. The scale 4 may have, for example, a configuration in which a pattern of a chromium reflection film is arranged in a grid pattern on a glass substrate. The displacement detector 10 may be configured to detect the relative displacement between the scale 4 and the displacement detector 10 arranged to face each other. Of the scale 4 and the displacement detector 10 constituting one detector DT, the scale 4 may be arranged on the structure ST, and the displacement detector 10 may be arranged on the circuit board 6 so as to face the scale 4. Alternatively, of the scale 4 and the displacement detector 10 constituting one detector DT, the scale 4 may be arranged on the circuit board 6, and the displacement detector 10 may be arranged on the structure ST so as to face the scale 4.

[0014] The calculation unit 20 can be configured to generate a plurality of temperature change information indicating changes in parameter values correlated with temperature based on the outputs of the plurality of detectors DT, and generate reliability information based on the plurality of temperature change information. For example, the calculation unit 20 can generate reliability information based on the mutual differences of the plurality of temperature change information. Alternatively, the calculation unit 20 can be configured to generate a plurality of evaluation result information based on the outputs of the plurality of detectors DT, and generate reliability information based on the plurality of evaluation result information. The evaluation result information may be information correlated with temperature, or may be information not correlated with temperature. The calculation unit 20 can be configured by, for example, a PLD (abbreviation for Programmable Logic Device) such as an FPGA (abbreviation for Field Programmable Gate Array), or an ASIC (abbreviation for Application Specific Integrated Circuit), or a general-purpose or dedicated computer in which a program is incorporated, or a combination of all or part of these.

[0015] FIG. 2 is a functional block diagram for exemplifying the operation of the force detection device 100 shown in FIG. 1. The displacement information respectively detected by the plurality of detectors DT is provided to the calculation unit 20. The calculation unit 20 can be configured to execute a first calculation 21 and a second calculation 22. The first calculation 21 can include a calculation for generating external force information indicating the external force received by the force detection device 100 and a plurality of temperature change information indicating changes in parameter values correlated with temperature based on the outputs of the plurality of detectors DT. The first calculation 21 may include a calculation for generating moment information indicating the moment received by the force detection device 100 based on the outputs of the plurality of detectors DT. The second calculation 22 can include a calculation for generating reliability information based on the mutual differences of the plurality of temperature change information. For example, the second calculation 22 can include a calculation for generating abnormality information indicating that an abnormality has occurred as reliability information when the mutual difference of the plurality of temperature change information exceeds a threshold value.

[0016] The outputs of the plurality of detectors DT may include first displacement information indicating the displacement of the deformation part 3 in the first direction and second displacement information indicating the displacement of the deformation part 3 in the second direction. The first calculation 21 may include a calculation for generating, as external force information, information indicating the external force in the first direction and information indicating the external force in the second direction. The plurality of temperature change information generated by the first calculation 21 may include first temperature change information indicating a temperature change calculated based on the first displacement information and second temperature change information indicating a second temperature change calculated based on the second displacement information. The first direction and the second direction are different from each other. For example, the first direction is the X direction and the second direction is the Y direction. The second calculation 22 may include a calculation for generating abnormal information when the difference between the first temperature change information and the second temperature change information exceeds a threshold value.

[0017] Figures 3A and 3B show an example in which the configuration of the force detection device 100 according to the first embodiment is further specified. Figure 3B is a cross-sectional view taken along the line A-A of Figure 3A. The force detection device 100 may include a structure ST including a deformation part 3 that elastically deforms in response to an external force, and a plurality of detectors DT that respectively detect displacements at a plurality of locations of the structure ST. Note that, in order to distinguish the plurality of detectors DT from each other, subscripts such as A, B, C, etc. are used. Specifically, the plurality of detectors DT are distinguished from each other as DTA, DTB, DTC, DTD, DTE, DTF, DT G, DTH. Each detector DT includes a scale 4 and a displacement detector 10. In order to distinguish the plurality of scales 4 from each other, subscripts such as A, B, C, etc. are used. Specifically, the plurality of scales 4 are distinguished from each other as 4A, 4B, 4C, 4D, 4E, 4F, 4G, 4H. Similarly, in order to distinguish the plurality of displacement detectors 10 from each other, subscripts such as A, B, C, etc. are used. Specifically, the plurality of displacement detectors 10 are distinguished from each other as 10A, 10B, 10C, 10D, 10E, 10F, 10G, 10H. Here, the scale 4 (for example, 4A) and the displacement detector 10 (for example, 10A) with the same subscript constitute one detector DT (for example, DTA). Note that only some of the scales 4 and / or displacement detectors 10 of the plurality of detectors DTA, DTB, DTC, DTD, DTE, DTF, DT G, DTH are shown in Figures 3A and 3B.

[0018] In addition to the deformation part 3, the structure ST may include a base part 1. The base part 1 may include, for example, a first member 11 having a frame shape or a cylindrical shape, and a second member 12 connected to the first member 11. The force-receiving part 2 and the first member 11 of the base part 1 are connected by the deformation part 3. The second member 12 is connected to the deformation part 3 via the first member 11, but is not directly connected to the deformation part 3.

[0019] The plurality of detectors DTA to DTH include a plurality of detectors (first detectors) DTA, DTD, DTE, DTH (only scales 4A, 4D, 4E, 4H are shown in FIG. 3A) that respectively detect the deformation of a plurality of locations (first locations) of the deformation part 3. The plurality of detectors DTA to DTH also include a plurality of second detectors DTB, DTC, DTF, DTG (only scales 4B, 4C, 4F, 4G are shown in FIG. 3A) that respectively detect the deformation of a plurality of locations (second locations) of the base part 1 (second part 12). In other words, the plurality of detectors DTA to DTH include at least one detector belonging to a first group that respectively detects the deformation of a plurality of locations of the deformation part 3, and at least one detector belonging to a second group that respectively detects the deformation of a plurality of locations of the base part 1.

[0020] In the example described in FIGS. 3A and 3B, displacement detectors 10A to 10H and an arithmetic unit 20 are arranged on the circuit board 6. Also, the detectors DTA, DTB, DTE, DTF are arranged to detect displacement in the X direction (an example of the first direction), and the detectors DTC, DTD, DTG, DTH are arranged to detect displacement in the Y direction (an example of the second direction).

[0021] Here, the arithmetic processing in the force detection device 100 will be exemplarily described. Assuming that the outputs of the detectors DTA to DTH (displacement detectors 10A to 10H) are Da to Dh respectively, the arithmetic unit 20 can calculate external force information (here, information regarding force and moment (torque)) and temperature change information according to Equation 1. Fx is the force in the X direction, Fy is the force in the Y direction, Fz is the force in the Z direction, Mx is the moment (torque) around the X axis, My is the moment around the Y axis, Mz is the moment around the Z axis, Tx is the temperature change obtained from the displacement in the X direction, and Ty is the temperature change obtained from the displacement in the Y axis direction. The transformation matrix, which is the first matrix on the right side of Equation 1, is a matrix for converting displacement information, which is the output of the detectors DTA to DTH (displacement detectors 10A to 10H), into external force information and temperature change information. k1, k2, l1, l2, m, n1, n2, О1, О2, p, q are coefficients for converting displacement information into external force information and temperature change information. The coefficients can be determined based on design values or measured values. q is a coefficient for converting displacement information into temperature change information.

[0022]

Number

[0023] According to Equation 1, the first temperature change information is calculated according to the displacement in the X direction based on the output De of the detector DTE (4E, 10E) that detects the displacement of a predetermined location of the deformation part 3 and the output Df of the detector DTF (4F, 10F) that detects the displacement of a predetermined location of the base part 1. Note that the first temperature change information may be calculated according to the displacement in the X direction based on the output of the detector DT that detects the displacement of at least one location of the deformation part 3 and the output of the detector DT that detects the displacement of at least one location of the base part 1.

[0024] Also, according to Equation 1, second temperature change information is calculated according to the displacement in the Y direction based on the output Dg of the detector DTG (4G, 10G) that detects the displacement of a predetermined location of the deformed portion 3 and the output Dh of the detector DTH (4H, 10H) that detects the displacement of a predetermined location of the base portion 1. Note that the second temperature change information may be calculated according to the displacement in the Y direction based on the output of the detector DT that detects the displacement of at least one location of the deformed portion 3 and the output of the detector DT that detects the displacement of at least one location of the base portion 1. The arithmetic unit 20 can calculate the difference between the first temperature change information and the second temperature change information, and generate abnormal information as reliability information when the difference exceeds a threshold value. The fact that the difference between the first temperature change information and the second temperature change information exceeds the threshold value suggests that an error component corresponding to the external force information is included or that it is incorrect. According to the first embodiment, it is possible to detect a temperature change without using a temperature sensor such as a thermistor.

[0025] Hereinafter, the force detection device 100 according to the second embodiment will be described with reference to FIGS. 4A and 4B. FIG. 4B is a cross-sectional view taken along the line B-B of FIG. 4A. Matters not mentioned as the second embodiment may follow the first embodiment. The force detection device 100 according to the second embodiment may include a structure ST including a deformation part 3 that elastically deforms in response to an external force, and a plurality of detectors DT that respectively detect displacements at a plurality of locations of the structure ST. Note that, in order to distinguish the plurality of detectors DT from each other, subscripts A, B, and C are used. Specifically, the plurality of detectors DT are distinguished from each other as DTA, DTB, and DTC. Each detector DT includes a scale 4 and a displacement detector 10. In order to distinguish the plurality of scales 4 from each other, subscripts A, B, and C are used. Specifically, the plurality of scales 4 are distinguished from each other as 4A, 4B, and 4C. Similarly, in order to distinguish the plurality of displacement detectors 10 from each other, subscripts A, B, and C are used. Specifically, the plurality of displacement detectors 10 are distinguished from each other as 10A, 10B, and 10C. Here, the scale 4 (for example, 4A) and the displacement detector 10 (for example, 10A) with the same subscript constitute one detector DT (for example, DTA). Note that, in FIG. 4A, the displacement detectors 10A, 10B, and 10C are not shown, and in FIG. 4B, the scale 4B and the displacement detector 10B are not shown.

[0026] In addition to the deformation part 3, the structure ST may include a base part 1. The base part 1 may include, for example, a first member 11 having a frame shape or a cylindrical shape, and a second member 12 connected to the first member 11. The force receiving part 2 and the first member 11 of the base part 1 are connected by the deformation part 3. The second member 12 is connected to the deformation part 3 via the first member 11, but is not directly connected to the deformation part 3.

[0027] The plurality of detectors DTA, DTB, and DTC include a first detector DTA (only the scale 4A is shown in FIG. 3A) that detects the deformation of one location (the first location) of the deformation part 3. The plurality of detectors DTA, DTB, and DTC also include a plurality of second detectors DTB and DTC (only the scales 4B and 4C are shown in FIG. 3A) that respectively detect the deformations of a plurality of locations (the second location) of the base part 1 (the second member 12).

[0028] In the examples described in FIGS. 4A and 4B, displacement detectors 10A, 10B, 10C and an arithmetic unit 20 are arranged on a circuit board 6. Further, detectors DTA and DTC are arranged to detect displacement in the X direction (an example of the first direction), and detector DTB is arranged to detect displacement in the Y direction (an example of the second direction).

[0029] Here, the arithmetic processing in the force detection device 100 will be exemplarily described. Assuming that the outputs of detectors DTA, DTB, and DTC (displacement detectors 10A, 10B, and 10C) are Da, Db, and Dc, respectively, the arithmetic unit 20 can calculate external force information and temperature change information according to Equation 2. Fx is the external force in the X direction, Tx is the temperature change obtained from the displacement in the X direction, and Ty is the temperature change obtained from the displacement in the Y-axis direction. The conversion matrix, which is the first matrix on the right side of Equation 2, is a matrix for converting displacement information, which is the output of detectors DTA, DTB, and DTC (displacement detectors 10, 10B, and 10C), into external force information and temperature change information. m1, m2, and n are coefficients for converting displacement information into external force information and temperature change information. The coefficients can be determined based on design values or measured values.

[0030]

Equation

[0031] According to Equation 2, first temperature change information corresponding to the displacement in the X direction is calculated based on the output Da of the detectors DTA(4A, 10A) that detect the displacement at a predetermined location of the deformed portion 3 and the output Dc of the detectors DTC(4C, 10C) that detect the displacement at a predetermined location of the base portion 1. Also, according to Equation 2, second temperature change information corresponding to the displacement in the Y direction is calculated based on the output Db of the detectors DTB(4B, 10B) that detect the displacement at a predetermined location of the base portion 1. The arithmetic unit 20 can calculate the difference between the first temperature change information and the second temperature change information, and generate abnormal information as reliability information when the difference exceeds a threshold value. The fact that the difference between the first temperature change information and the second temperature change information exceeds the threshold value suggests that an error component corresponding to other information, external force information, is included or that it is incorrect.

[0032] Figure 5 is a diagram showing a schematic configuration of the transfer device 400. The transfer device 400 may include a robot arm 200 as a movable part, a force detection device 100, a gripping part 201, and a control part 210. The gripping part 201 is one of the movable parts that can grip the workpiece 205 by a closing operation and release the gripped workpiece 205 by an opening operation. Here, the transfer device 400 performs an operation in which the gripping part 201 grips the workpiece 205 at a predetermined position and inserts the gripped workpiece 205 into a hole 206a formed in the substrate 206, and the control part 210 controls this operation.

[0033] The force detection device 100 disposed between the robot arm 200 and the gripping part 201 detects the upward external force F that the gripping part 201 receives from the substrate 206 via the workpiece 205. For example, when the workpiece 205 is in contact with a portion of the upper surface of the substrate 206 other than the hole portion 206a, an external force F having an appropriate magnitude acts on the force detection device 100 from the gripping part 201, so it is detected that the position of the workpiece 205 has deviated from the position of the hole portion 206a. Therefore, the control unit 210 can control the operation of the robot arm 200 to move the workpiece 205 along the upper surface of the substrate 206. And when the workpiece 205 is positioned above the hole portion 206a, the control unit 210 can detect that the position of the workpiece 205 has coincided with the position of the hole portion 206a because the external force F that has been acting on the force detection device 100 through the gripping part 201 becomes smaller. Then, after the control unit 210 controls the operation of the robot arm 200 to insert the workpiece 205 into the hole portion 206a, the control unit 210 can control the gripping part 201 to release the workpiece 205.

[0034] As described above, in the transfer device 400, by using the force detection device 100, the operation of the robot arm 200 can be controlled with high precision. Note that the force detection device 100 is also applicable to devices other than the transfer device 400.

[0035] In the above embodiment, an example in which the external force (force and moment (torque)) is detected with respect to six axes is shown as the force detection device 100, but the force detection device may be configured as a force sensor that detects only force or a torque sensor that detects only torque.

[0036] This specification and the drawings include the following disclosures. (Item 1) A structure including a deformation part that elastically deforms in response to an external force, A plurality of detectors that respectively detect displacements at a plurality of locations of the structure, Based on the outputs of the plurality of detectors, an arithmetic unit that generates and outputs external force information indicating the external force and reliability information indicating the reliability of the external force information, The calculation unit generates a plurality of temperature change information indicating changes in parameter values correlated with temperature based on the outputs of the plurality of detectors, and generates the reliability information based on the plurality of temperature change information. A force detection device characterized by the above. (Item 2) The calculation unit generates the reliability information based on the mutual differences of the plurality of temperature change information. The force detection device according to Item 1, characterized by the above. (Item 3) When the mutual differences of the plurality of temperature change information exceed a threshold value, the calculation unit generates abnormality information indicating that an abnormality has occurred as the reliability information. The force detection device according to Item 2, characterized by the above. (Item 4) The outputs of the plurality of detectors include first displacement information indicating displacement in a first direction of the deformation part and second displacement information indicating displacement in a second direction of the deformation part. The plurality of temperature change information includes first temperature change information indicating a temperature change calculated based on the first displacement information and second temperature change information indicating a second temperature change calculated based on the second displacement information. The first direction and the second direction are different from each other. The calculation unit generates the abnormality information when the difference between the first temperature change information and the second temperature change information exceeds the threshold value. The force detection device according to Item 3, characterized by the above. (Item 5) The first direction and the second direction are orthogonal to each other. The force detection device according to Item 4, characterized by the above. (Item 6) The calculation unit generates information indicating an external force in the first direction and information indicating an external force in the second direction as the external force information. The force detection device according to Item 5, characterized by the above. (Item 7) Further comprising a force receiving part that receives an external force. The structure further includes a base portion, and the base portion is connected to the force receiving portion via the deformation portion. The plurality of detectors includes a plurality of first detectors that respectively detect deformations at a plurality of first locations of the deformation portion, and a plurality of second detectors that respectively detect deformations at a plurality of second locations of the base portion. The force detection device according to any one of Items 1 to 6, characterized in that. (Item 8) The calculation unit generates first temperature change information corresponding to the displacement in the first direction of the deformation portion based on at least one output of the plurality of first detectors and at least one output of the plurality of second detectors. generates second temperature change information corresponding to the displacement in the second direction of the deformation portion based on at least one output of the plurality of first detectors and at least one output of the plurality of second detectors. generates the reliability information based on the first temperature change information and the second temperature change information. The force detection device according to Item 7, characterized in that. (Item 9) The calculation unit generates the reliability information based on the difference between the first temperature change information and the second temperature change information. The force detection device according to Item 8, characterized in that. (Item 10) When the difference exceeds a threshold value, the calculation unit generates abnormal information indicating that an abnormality has occurred as the reliability information. The force detection device according to Item 9, characterized in that. (Item 11) The force detection device further includes a force receiving portion that receives an external force. The structure further includes a base portion, and the base portion is connected to the force receiving portion via the deformation portion. The plurality of detectors includes a first detector that detects the deformation at a first location of the deformation portion, and a plurality of second detectors that respectively detect deformations at a plurality of second locations of the base portion. The force detection device according to any one of Items 1 to 6, characterized in that. (Item 12) The arithmetic unit generates first temperature change information corresponding to the displacement of the deformation part in the first direction based on the output of the first detector and the output of one of the plurality of second detectors, generates second temperature change information corresponding to the displacement of the deformation part in the second direction based on the output of another one of the plurality of second detectors, and generates the reliability information based on the first temperature change information and the second temperature change information. The force detection device according to item 11, characterized in that. (Item 13) The arithmetic unit generates the reliability information based on the difference between the first temperature change information and the second temperature change information. The force detection device according to item 12, characterized in that. (Item 14) When the difference exceeds a threshold value, the arithmetic unit generates abnormality information indicating that an abnormality has occurred as the reliability information. The force detection device according to item 13, characterized in that. (Item 15) a structure including a deformation part that elastically deforms in response to an external force, a plurality of detectors that respectively detect displacements at a plurality of locations of the structure, and an arithmetic unit that generates and outputs external force information indicating the external force and reliability information indicating the reliability of the external force information based on the outputs of the plurality of detectors. The plurality of locations are locations where the deformation of the deformation part in the first direction and the deformation of the deformation part in a second direction different from the first direction can be obtained based on the outputs of the plurality of detectors. A force detection device, characterized in that. (Item 16) further comprising a force receiving part that receives an external force, the structure further includes a base part, and the base part is connected to the force receiving part via the deformation part. The plurality of detectors includes a plurality of first detectors that respectively detect deformations at a plurality of first locations of the deformation part, and a plurality of second detectors that respectively detect deformations at a plurality of second locations of the base part. The arithmetic unit generates the reliability information based on at least one output of the plurality of first detectors and the outputs of the plurality of second detectors. The force detection device according to item 15, characterized in that. (Item 17) Further comprising a force-receiving part that receives an external force. The structure further includes a base part, and the base part is connected to the force-receiving part via the deformation part. The plurality of detectors includes a first detector that detects deformation at a first location of the deformation part, and a plurality of second detectors that respectively detect deformations at a plurality of second locations of the base part. The arithmetic unit generates the reliability information based on the output of the first detector and the outputs of the plurality of second detectors. The force detection device according to item 15, characterized in that. (Item 18) A movable part, The force detection device according to any one of items 1 to 17, A control unit that controls the operation of the movable part based on the output of the force detection device, A transport device, characterized by comprising.

[0037] The invention is not limited to the above embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the claims are attached to disclose the scope of the invention.

Description of Reference Numerals

[0038] ST: Structure, 2: Force-receiving part, 3: Deformation part, 4: Scale, 10: Displacement detector, DT: Detector, 20: Arithmetic unit, 100: Force detection device

Claims

1. A structure including a deformable portion that elastically deforms in response to an external force, a plurality of detectors that respectively detect displacements at a plurality of locations of the structure, and a calculation unit that generates and outputs external force information indicating the external force and reliability information indicating the reliability of the external force information based on outputs of the plurality of detectors. The calculation unit generates a plurality of temperature change information respectively indicating changes in parameter values correlated with temperature based on the outputs of the plurality of detectors, and generates the reliability information based on the plurality of temperature change information. A force detection device characterized by the above.

2. The calculation unit generates the reliability information based on mutual differences between the plurality of temperature change information. The force detection device according to claim 1, characterized by the above.

3. When the mutual differences between the plurality of temperature change information exceed a threshold value, the calculation unit generates abnormality information indicating that an abnormality has occurred as the reliability information. The force detection device according to claim 2, characterized by the above.

4. Outputs of the plurality of detectors include first displacement information indicating displacement in a first direction of the deformable portion and second displacement information indicating displacement in a second direction of the deformable portion. The plurality of temperature change information includes first temperature change information indicating a temperature change calculated based on the first displacement information and second temperature change information indicating a second temperature change calculated based on the second displacement information. The first direction and the second direction are different from each other. The calculation unit generates the abnormality information when a difference between the first temperature change information and the second temperature change information exceeds the threshold value. The force detection device according to claim 3, characterized by the above.

5. The first direction and the second direction are orthogonal to each other. The force detection device according to claim 4, characterized by the above.

6. The calculation unit generates information indicating an external force in the first direction and information indicating an external force in the second direction as the external force information. The force detection device according to claim 5, characterized by the above.

7. Further comprising a force receiving portion that receives an external force, the structure further includes a base portion, and the base portion is connected to the force receiving portion via the deformable portion. The plurality of detectors include a plurality of first detectors that respectively detect deformations at a plurality of first locations of the deformable portion and a plurality of second detectors that respectively detect deformations at a plurality of second locations of the base portion. The force detection device according to claim 1, characterized by the above.

8. The calculation unit generates first temperature change information corresponding to the displacement of the deformation part in the first direction based on at least one output of the plurality of first detectors and at least one output of the plurality of second detectors, generates second temperature change information corresponding to the displacement of the deformation part in the second direction based on at least one output of the plurality of first detectors and at least one output of the plurality of second detectors, and generates the reliability information based on the first temperature change information and the second temperature change information. The force detection device according to claim 7, wherein the force detection device is characterized in that.

9. The calculation unit generates the reliability information based on the difference between the first temperature change information and the second temperature change information. The force detection device according to claim 8, wherein the force detection device is characterized in that.

10. When the difference exceeds a threshold value, the calculation unit generates abnormality information indicating that an abnormality has occurred as the reliability information. The force detection device according to claim 9, wherein the force detection device is characterized in that.

11. Further comprising a force receiving part that receives an external force, the structure further includes a base part, and the base part is connected to the force receiving part via the deformation part, the plurality of detectors include a first detector that detects the deformation of a first location of the deformation part and a plurality of second detectors that respectively detect the deformations of a plurality of second locations of the base part. The force detection device according to claim 1, wherein the force detection device is characterized in that.

12. The calculation unit generates first temperature change information corresponding to the displacement of the deformation part in the first direction based on the output of the first detector and the output of one of the plurality of second detectors, generates second temperature change information corresponding to the displacement of the deformation part in the second direction based on the output of the other one of the plurality of second detectors, and generates the reliability information based on the first temperature change information and the second temperature change information. The force detection device according to claim 11, wherein the force detection device is characterized in that.

13. The calculation unit generates the reliability information based on the difference between the first temperature change information and the second temperature change information. The force detection device according to claim 12, wherein the force detection device is characterized in that.

14. When the difference exceeds a threshold value, the calculation unit generates abnormality information indicating that an abnormality has occurred as the reliability information. The force detection device according to claim 13, wherein the force detection device is characterized in that.

15. A structure including a deformation part that elastically deforms in response to an external force, A plurality of detectors that respectively detect displacements at a plurality of locations of the structure; An arithmetic unit that generates and outputs external force information indicating the external force and reliability information indicating the reliability of the external force information based on the outputs of the plurality of detectors; The plurality of locations are a plurality of locations where deformation of the deformed part in the first direction and deformation of the deformed part in a second direction different from the first direction can be acquired based on the outputs of the plurality of detectors. A force detection device characterized by this.

16. Further comprising a force receiving part that receives an external force, The structure further includes a base part, and the base part is connected to the force receiving part via the deformed part, The plurality of detectors include a plurality of first detectors that respectively detect deformation of a plurality of first locations of the deformed part, and a plurality of second detectors that respectively detect deformation of a plurality of second locations of the base part, The arithmetic unit generates the reliability information based on at least one output of the plurality of first detectors and the outputs of the plurality of second detectors. The force detection device according to claim 15, characterized by this.

17. Further comprising a force receiving part that receives an external force, The structure further includes a base part, and the base part is connected to the force receiving part via the deformed part, The plurality of detectors include a first detector that detects deformation of a first location of the deformed part, and a plurality of second detectors that respectively detect deformation of a plurality of second locations of the base part, The arithmetic unit generates the reliability information based on the output of the first detector and the outputs of the plurality of second detectors. The force detection device according to claim 15, characterized by this.

18. A movable part, The force detection device according to any one of claims 1 to 17, A control unit that controls the operation of the movable part based on the output of the force detection device, A transport device characterized by comprising this.

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