JP2021085756A - Detection device, drive unit, robotic device, detection method, method of manufacturing articles using robotic device, control program, and recording medium - Google Patents

Abstract

To provide a compact detection device.SOLUTION: A detection device 221 is provided, comprising a first part, a second part linked with the first part via a linkage part, a first sensor configured to output a signal corresponding to a relative displacement between the first and second parts, and a sensor board 21s having the first sensor mounted thereon, where the sensor board 21s is located between the first and second parts.SELECTED DRAWING: Figure 4

Description

The present invention relates to a detection device.

A robot device that operates according to a robot program is used for the purpose of producing goods. For the production of articles that require accuracy in assembly operations, a control method is used in which a detection device that can acquire force information such as torque is placed in the robot device and the force acting on the joints is measured to control the robot operation. Has been done. As this type of detection device, a detector capable of detecting the displacement of the structure constituting the detection device as described in Patent Document 1 is used, and the torque acting on the joint based on the detected displacement and the rigidity of the structure is used. There is a torque sensor that detects.

JP-A-2017-120243

However, the detection device described in Patent Document 1 only describes the appropriate rigidity of the transmission member constituting the detection device, and does not describe the miniaturization of the detection device. In the miniaturization of the detection device, it is very important from the viewpoint of the controllability of the robot device, and consideration of miniaturization including the arrangement of the detector that detects the displacement of the structure used in the detection device such as the encoder is examined. is required.

In view of the above problems, an object of the present invention is to provide a small detection device.

In order to solve the above problems, in the present invention, according to the relative displacement between the first part, the second part connected to the first part via the connecting part, and the first part and the second part. A first sensor for outputting a signal and a substrate on which the first sensor is mounted are provided, and the substrate is provided between the first portion and the second portion. A detection device was adopted.

According to the present invention, the detection device can be miniaturized.

It is a perspective view of the robot apparatus 100 which concerns on embodiment. It is a control block diagram of the robot apparatus 100 which concerns on embodiment. It is a partial cross-sectional view of the joint J1 which concerns on embodiment. It is a perspective view of the detection device 221 which concerns on embodiment. It is a block diagram of the detector of the detection device 221 which concerns on embodiment. It is a top view when the detection device 221 according to the embodiment is provided in the robot arm main body 200. It is a block diagram of the detection device 221 which concerns on embodiment.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the accompanying drawings. The embodiments shown below are merely examples, and the detailed configuration can be appropriately changed without departing from the spirit of the present invention. Further, the numerical values taken up in the present embodiment are reference numerical values and do not limit the present invention.

(First Embodiment)
FIG. 1 is a plan view of the robot device 100 according to the present embodiment as viewed from a certain direction in the XYZ coordinate system. In the following drawings, the arrows X, Y, and Z in the drawing indicate the coordinate system of the entire robot device 100. Generally, in a robot system using a robot device, the XYZ three-dimensional coordinate system may appropriately use a local coordinate system for the robot hand, fingers, etc., depending on the convenience of control, in addition to the global coordinate system of the entire installation environment. .. In the present embodiment, the coordinate system of the entire robot device 100 is represented by XYZ, and the local coordinate system is represented by xyz.

As shown in FIG. 1, the robot device 100 includes an articulated robot arm main body 200, a robot hand main body 300, and a control device 400 that controls the operation of the robot arm main body 200.

Further, an external input device 500 is provided as a teaching device for transmitting teaching data to the control device 400. An example of the external input device 500 is a teaching pendant, which is used by an operator to specify the positions of the robot arm main body 200 and the robot hand main body 300.

In the present embodiment, the case where the end effector provided at the tip of the robot arm main body 200 is a robot hand will be described, but the present invention is not limited to this, and a tool or the like may be used.

The link 201, which is the base end of the robot arm main body 200, is provided on the base 210. The robot hand body 300 grips an object such as a part or a tool. The robot hand body 300 of the present embodiment opens and closes two finger portions 301 by a drive mechanism (not shown in detail) to grip or open an object. It suffices if the object can be gripped so as not to be displaced relative to the robot arm main body 200.

The robot hand body 300 is connected to the link 206, and by rotating the link 206, the robot hand body 300 can also be rotated.

The robot arm body 200 has a plurality of joints, for example, six joints (six axes). The robot arm main body 200 has a plurality of (six) servomotors 211 to 216 that rotationally drive the joints J1 to J6 around the rotation axes A1 to A6, respectively.

In the robot arm main body 200, a plurality of links 201 to 206 are rotatably connected by joints J1 to J6. Here, the links 201 to 206 are sequentially connected in series from the base end side to the tip end side of the robot arm main body 200.

The robot arm body 200 can point the end effector (robot hand body 300) of the robot arm body 200 in any three-dimensional posture at any three-dimensional position as long as it is within the movable range.

Here, the hand of the robot arm main body 200 is the robot hand main body 300 in the present embodiment. When the robot hand main body 300 holds an object, it is referred to as a hand of the robot arm main body 200 including the robot hand main body 300 and the holding object (for example, a part or a tool).

That is, the robot hand body 300, which is an end effector, is called a hand regardless of whether the robot hand body 300 is holding an object or not.

With the above configuration, the robot arm main body 200 can operate the robot hand main body 300 at an arbitrary position to perform a desired work. The desired work is, for example, a work of assembling objects to each other to manufacture an article.

FIG. 2 is a block diagram showing the configuration of the robot device 100 according to the present embodiment. The control device 400 is composed of a computer, and the control device 400 is composed of a computer and includes a CPU (Central Processing Unit) 401 as a control unit (processing unit).

Further, the control device 400 includes a ROM (Read Only Memory) 402, a RAM (Random Access Memory) 403, and an HDD (Hard Disk Drive) 404 as storage units. Further, the control device 400 includes a recording disk drive 405, and is connected to various interfaces 406 to 409, 411, 412 via a bus 410.

A ROM 402, a RAM 403, an HDD 404, a recording disk drive 405, and various interfaces 406 to 409, 411, and 412 are connected to the CPU 401 via a bus 410. A basic program such as a BIOS is stored in the ROM 402. The RAM 403 is a storage device that temporarily stores various data such as the calculation processing result of the CPU 401.

The HDD 404 is a storage device that stores the arithmetic processing results of the CPU 401, various data acquired from the outside, and the like, and also records the program 430 for causing the CPU 401 to execute the arithmetic processing. The CPU 401 executes each step of the robot control method based on the program 430 recorded (stored) in the HDD 404.

The recording disc drive 405 can read various data, programs, and the like recorded on the recording disc 431.

The external input device 500 is connected to interface 406. The CPU 401 receives input of teaching data from the external input device 500 via the interface 406 and the bus 410.

The arm motor driver 230 is connected to the interface 409. Each of the motors 211 to 216 is provided with input shaft encoders 231 to 236, which are encoders for detecting the rotation angle of the rotation shaft of the motor. The CPU 401 acquires detection results from the input shaft encoders 231 to 236 via the arm motor driver 230, the interface 409, and the bus 410.

Further, the CPU 401 outputs the command value data of each joint to the arm motor driver 230 via the bus 410 and the interface 409 at predetermined time intervals. Further, detection devices 221 to 226 for detecting the rotation angle and torque on the output side of each of the links 201 to 206 are connected to the CPU 401 via the interface 411 and the bus 410. The CPU 401 acquires the detection result from each of the detection devices 221 to 226 via the interface 411 and the bus 410.

Similarly, the hand motor driver 330 is also connected to the interface 412 and is provided so as to be able to communicate with the CPU 401 via the bus 410. The CPU 401 outputs the command value data of each finger portion 301 of the robot hand main body 300 to the hand motor driver 330 via the bus 410 and the interface 411 at predetermined time intervals. Although not shown, it is assumed that the robot hand body 300 is provided with a motor for driving the finger portion 301 and is connected to the hand motor driver 330.

A monitor 421 is connected to the interface 407, and various images are displayed on the monitor 421 under the control of the CPU 401. The interface 408 is configured to be connectable to an external storage device 422, which is a storage unit such as a rewritable non-volatile memory or an external HDD.

In the present embodiment, the case where the computer-readable recording medium is the HDD 404 and the program 430 is stored in the HDD 404 will be described, but the present invention is not limited to this. The program 430 may be recorded on any recording medium as long as it can be read by a computer.

For example, as a recording medium for supplying the program 430, a ROM 402, a recording disk 431, an external storage device 422, or the like may be used. To give a specific example, flexible disks, hard disks, optical disks, magneto-optical disks, CD-ROMs, CD-Rs, magnetic tapes, non-volatile memories, ROMs, and the like can be used as recording media.

FIG. 3 is a partial cross-sectional view showing the joint J1 of the robot arm main body 200 in the present embodiment. Hereinafter, the joint J1 will be described as an example, and the other joints J2 to J6 may have different sizes and performances, but since they have the same configuration, the description thereof will be omitted.

The joint J1 is arranged between the base 210 shown in FIG. 1 and the link 201, and has an electric motor 211. The motor 211 is a servomotor, for example, a brushless DC servomotor or an AC servomotor. The motor 211 has a housing 14 to which a stator (not shown) is fixed, and a shaft (hereinafter, referred to as "motor rotation shaft") 15 connected to a rotor (not shown). Further, the joint J1 has a speed reducer 11 that reduces and outputs the rotation of the motor rotation shaft 15 of the motor 211. The motor 211 is provided with an input shaft encoder 231 that detects the rotation angle of the motor rotation shaft 15.

Further, in the joint J1, the base 210 and the link 201 have a hole 59 for wiring. Further, the speed reducer 11 rotates the link 201 relative to the base 210. The motor rotating shaft 15 of the motor 211, the link 201 on the output side of the speed reducer 11, and the structure 4 described later rotate about the rotating shaft A1. That is, the rotation axis A1 is the rotation axis of the link 201.

The speed reducer 11 may be any speed reducer, but a strain wave gearing speed reducer is preferable, and in the present embodiment, it is a wave gear speed reducer. The speed reducer 11 has a web generator 16 which is a shaft (input shaft) on the input side of the speed reducer, which is connected to the motor rotation shaft 15 of the motor 211. Further, the speed reducer 11 has a flexspline 17 which is a shaft (output shaft) on the output side of the speed reducer. Further, the speed reducer 11 has a circular spline 18 which is a fixed shaft.

The housing 14 of the motor 211 is bolted to the base 210. Further, the circular spline 18 and the outer ring of the cross roller bearing 20 are fixed to the base 210. The output side rotation shaft 19 is fixed to the flexspline 17.

The output side rotating shaft 19 is fixed to the inner ring of the cross roller bearing 20. Although the flexspline 17 and the output side rotating shaft 19 are separately configured, they may be integrated. Further, although the output side rotating shaft 19 and the link 201 are configured separately, they may be integrated. Further, the flexspline 17, the output side rotating shaft 19 and the link 201 may be integrated.

The web generator 16 has an elliptical cam 161 and a rolling bearing 162 provided on the outer circumference of the elliptical cam 161. The motor rotation shaft 15 of the motor 211 is connected to the elliptical cam 161 of the web generator 16.

The flexspline 17 has a cup-shaped thin-walled body portion 171 and a mounting portion 172 provided on the body portion 171 to which the output-side rotating shaft 19 is attached. A plurality of teeth are provided on the outer side of the body portion 171 in the circumferential direction. The body portion 171 is elliptical deformed by the web generator 16. The circular spline 18 is an internal gear having more teeth than the flexspline 17.

The web generator 16 spreads the flexspline 17 in an elliptical shape and engages the circular spline 18 and the elliptical cam 161 at two locations in the major axis direction. The flexspline 17 is repeatedly displaced in the radial direction at a rate of two cycles per rotation of the web generator 16. At this time, since the number of teeth of the flexspline 17 and the circular spline 18 are different, when the web generator 16 rotates once, the flexspline 17 rotates by the difference in the number of teeth with respect to the circular spline 18.

With the above configuration, when the motor rotating shaft 15 of the motor 211 rotates around the rotating shaft A1, the web generator 16 of the speed reducer 11 rotates around the rotating shaft A1, and the flexspline 17 is decelerated with respect to the base 210. The link 201 rotates relative to the rotation axis A1. Therefore, the output side rotating shaft 19 fixed to the flexspline 17 and the link 201 fixed to the output side rotating shaft 19 rotate relative to the base 210 around the rotating shaft A1. The rotation angle on the output side of the speed reducer 11 is the relative angle of the link 201 with respect to the base 210, that is, the rotation angle of the joint J1.

Further, the joint J1 has a structure 4 arranged on the output side of the speed reducer 11. The structure 4 is a member used for detecting torque. The structure 4 has a first ring 28, a second ring 29, and a plurality of leaf springs 30 as connecting portions.

The plurality of leaf springs 30 are arranged at intervals in the circumferential direction about the rotation axis A1 so as to connect the first ring 28 and the second ring 29. _{Further, a detection head 9 1} for detecting the relative displacement between the first ring 28 and the second ring 29 and a scale 8 ₁ are provided. The detection head 9 ₁ is provided on the sensor board 21, and transmits the information acquired by the _{detection head 9 1 to the control device 400 via wiring.}

Also, the scale 6 and the detection head ₇₁ for detecting the rotation angle of the output side of the speed reducer 11 is provided in the joint J1. Scale 6 is provided on the base 210, the detection head ₇₁ is provided on the sensor substrate 21. Further the first ring 28 has an opening 40 is provided, the detection head ₇₁ therefrom is provided so as to face the scale 6. Then, the detection head 7 ₁ transmits the acquired information to the control device 400 via the wiring 27 in the same manner as the detection head 91 _1. The structure, each detection head, scale, and sensor substrate shown above constitute a detection device 221 that detects the torque and rotation angle on the output side of the speed reducer 11.

4 (a) and 4 (b) are detailed views of the detection device 221. From FIG. 4A, the plurality of leaf springs 30 are provided so as to be perpendicular to the main surface of the first ring 28 and the main surface of the second ring 29, and are arranged radially around the rotation axis A1. ing. Each part of the structure 4 is made of a predetermined material having an elastic (spring) coefficient according to a target torque detection range and its required resolution, for example, a resin or a metal (steel material, stainless steel, etc.) material.

Leaf springs are characterized by lower rigidity in the bending direction than in other directions. Therefore, due to such an arrangement of the leaf spring 30, in the coordinate system in the drawing, only the rotation direction θ around the rotation axis A1 in the Z-axis direction is soft, and the structure is hard in the rotation directions around the other X and Y axes. Can be realized. It is important to increase the rigidity ratio in this way for the structure for detecting torque. If the rigidity in the direction in which torque is not detected is high, the deformation associated therewith becomes small, and the measurement error can be reduced.

Also from FIG. 4 (a), the detector 221 includes a detection head ₇₁ that detects the rotation angle of the output side of the reduction gear 11, and the detection head 7 _2, the detection head for detecting the output side of the torque of the reduction gear 11 9 with _1, and _{9 2.} In FIG. 4 (a), the detection head _{7 1} and _{7 2,} the detection head _{9 1} and _{9 2} are shown in Figure 4 (b).

FIG. 4 (a), the more FIG. 4 (b), the detection device 221 includes a scale 6 arranged so as to face the detection head _{7 1} and _{7 2.} The relative angle of the link 201 with respect to the base 210, that is, the rotation angle of the joint J1, changes within the movable range. By each detection head ₇₁ and 7 ₂ in order to detect the angle of the joint in a wide range, the scale 6 is required one turn is formed into a ring shape. A pattern is formed on the scale 6 in the circumferential direction. By the scale 6 and the detection head 7 ₁ and 7 _2, configured as an output shaft encoder for the rotation angle detection.

Although it is a rotary encoder in this embodiment, it may be either an incremental type or an absolute type, and the displacement detection method may be any of an optical type, a magnetic type, and a capacitance type. In this embodiment, it is an optical type. That is, each of the detection head 7 ₁ and 7 _2, a light-emitting portion and a light receiving unit, by irradiating light to the scale 6, for receiving reflected light from the scale 6. Each of the detection heads 7 ₁ and 7 ₂ performs photoelectric conversion and outputs an electric signal.

The 4 from (b), the detection device 221, the detection head _{9 1} and _{9 2} (see FIG. 4 (b) In the detection head _{9 2} is not shown) scale _{8 1} and _{8 2} disposed so as to face the respective Has. For detecting the respective detection head 9 ₁ and 9 ₂ are only minute amount of deformation of the plate spring 30 of the structure 4 (e.g. 50 [mu] m). Therefore, the scale _{8 1} and _{8 2} need only the circumference of the portion. By the scale _{8 1} and _{8 2} and the detection head _{9 1} and _{9 2,} constitute a detector for detecting the torque. The detector for detecting torque is the same as the output shaft encoder described above. That is, the detection head 9 ₁ has a light emitting portion and a light receiving unit, by irradiating light to the scale _81, for receiving reflected light from the scale _81. Detection head 9 ₂ also has a light emitting portion and a light receiving unit, by irradiating light to the scale _82, for receiving the reflected light from the scale 8 _2.

Each detection head 9 ₁ and 9 ₂ outputs an electric signal by photoelectric conversion. Note the detection head 9 ₁ and 9 ₂ is actually the one that relative displacement in a circumferential direction relative to the scale 8 ₁ and 8 _2, since the displacement amount is small (e.g. 50 [mu] m), the linear direction It can be regarded as a relative displacement. Therefore, the torque detection encoder may be a linear encoder. If a linear encoder is used, the detection device 221 can be easily manufactured.

Figure 4 (a), 4 (b), the these detection head _71, 7 2, _{9 1} and _{9 2} are detection head ₇₁ in (sensor substrate 21 to the two sides of the same coin to the sensor substrate 21, _{7 2} is the detection head 9 _1, 9 ₂ on the back surface which is provided) is mounted. Further, the sensor board 21 is provided with a processing circuit 25 having a function of processing a signal received from each detection head and a function of transmitting and receiving data. The processing circuit 25 is composed of one semiconductor package and is arranged (mounted) on the sensor board 21.

On the sensor board 21, a connector 26 is arranged (mounted) as a connection portion electrically connected to the wiring 27 (FIG. 3) including the power supply line and the signal line electrically connected to the robot control device 400 (FIG. 1). ) Has been done. That is, the detection devices 221 to 226 arranged at each joint are electrically connected to the control device 400.

Here, FIG. 5 shows a block diagram showing the devices mounted on the sensor board 21 of the detection device 221 in blocks. From FIGS. 4A and 5, the sensor substrate 21 is separated into a sensor substrate 21m and a sensor substrate 21s, and connection connectors 80a and 80b for connecting the sensor substrate 21m and the sensor substrate 21s are provided. ..

As a result, the data once processed by the processing circuit 25 provided on the sensor board 21s can be sent to the processing circuit 25 provided on the sensor board 21m via the connector 80a and 80b. As a result, the processing circuit 25 provided on the sensor board 21m can send the results of all the detection heads to the robot control device 400, and communication is possible without increasing the wiring arranged inside the robot arm main body 200.

Detection head ₇ 2 mounted on the sensor substrate 21s, _{9 2} is also possible to connect to the connector 80a, directly through 80b, the processing circuit 25 provided in the sensor substrate 21s. In that case, the processing circuit mounted on the sensor substrate 21s is unnecessary. As for the power supply circuit (not shown), the necessary parts for the sensor boards 21m and 21s can be used at the same time via the connector 80a and 80b, and one of them can be eliminated.

Further, from FIGS. 4 (a) and 4 (b), the structure 4 is composed of a first ring 28, a second ring 29, and leaf springs 30 arranged radially connecting both of them. In such a structure in which a plurality of leaf springs 30 are arranged, it may be difficult to install the sensor substrate 21 between the first ring 28 and the second ring 29 due to size restrictions. On the other hand, the sensor substrate 21 of the present embodiment is provided with a protruding portion protruding outward in the radial direction of the rotating shaft A1, and a processing circuit and a connector are mounted on the protruding portion, and the first ring 28 It is installed between the second ring 29 and the second ring 29.

As a result, the space created when the leaf spring 30 required for relative displacement of the first ring 28 and the second ring 29 is arranged can be effectively utilized as the arrangement place of the detection device. As a result, the thickness of the detection device 212 in the Z-axis direction can be reduced.

Further, from FIG. 4A, an opening 40 is provided in the first ring 28 of the structure 4. The detection heads 7 ₁ and 7 ₂ can be arranged in the opening 40 so as to face the scale 6 without a shield. Further in FIG. 4 (b) from the sensor substrate 21, are arranged detection head ₉ 1, _{9 2} on the back side of the detection head _{71, 7 2} are provided surface. As a result, the detection device 212 can be provided with an angle detection function and a torque detection function, and can be operated as both detection devices. From the above, since it is possible to suppress an increase in the number of sensor substrates by increasing the number of detection heads, it is possible to provide a thinner detection device.

Further, from FIGS. 4A and 4B, the sensor substrates 21m and 21s are structured by bolts 10m, 10s, 12m and 12s and mounting mechanisms 22m and 22s (the mounting mechanism 22s is not shown in FIG. 4A). It is attached to 4. The mounting mechanisms 22m and 22s are fixed to the first ring 28 of the structure 4 by bolts 10m and 10s. Further, the sensor substrates 21m and 21s are fixed to the mounting mechanisms 22m and 22s by bolts 12m and 12s, respectively. Furthermore, the mounting mechanism 22m, the 22s, the detection head ₉ 1, _{9 2,} are also provided openings for irradiating light to the scale _{81, 82.}

Here, in order for the bolts 12m and 12s to be inserted, the holes provided in the sensor substrates 21m and 21s are made larger than the screw portions of the bolts 12m and 12s and have a diameter smaller than the screw head. The mounting portions 22m and 22s are provided with screw holes so that the screw portions of the bolts 12m and 12s mesh with each other.

As a result, by loosening the bolts 12m and 12s to the extent that they do not come off from the screw holes, the sensor substrates 21m and 21s can be moved by the size of the provided holes with the bolts 12m and 12s as the base axis, and the structure 4 It is possible to slightly change the position in the circumferential direction θ of. With the position-adjusting mechanism described above, the separated sensor board each independently can be movable, the positional relationship between the detection head 9 ₁ and 9 _2, and the positional relation between the detection head 7 ₁ and 7 ₂ , The position can be easily adjusted.

FIG. 6 is a cross-sectional view when the detection device 221 according to the present embodiment is arranged in the robot arm main body 200. Since the space A is the central part of the joint of the robot arm main body 200, a motor, a speed reducer, and wiring (power line, control line) are arranged. Therefore, it can be seen that the hollow structure of the structure 4 of the present invention is suitable for the joint arrangement of the robot arm.

In addition, the relative positional relationship of each detection head may shift due to a crash or the like. In such a case, it may be necessary to remove the detection device 221 from the robot device and readjust the relative positions of the detection heads. However, in the present embodiment, by loosening the bolts 12 m and 12 s by the position adjusting mechanism described above, the sensor substrates 21 m and 21 s that protrude in the radial direction are gripped while the detection device 221 is attached to the robot arm main body 200. Can be moved.

Therefore, it is possible to manually adjust the position of each detection sensor. From the above, it is possible to easily adjust the position of each detection head even after the detection device 221 is mounted on the robot arm main body 200.

FIG. 7 is a block diagram of the detection device 221 according to the present embodiment. In FIG. 7, the processing circuit 25 mounted on the sensor substrate 21s is taken as an example. The processing circuit 25 shown in FIG. 7 is composed of, for example, a microcomputer. The processing circuit 25 has a CPU 251. Further, the processing circuit 25 has a ROM 251 and a RAM 253 as a storage unit. Further, the processing circuit 25 has a bus 254 and a plurality of interfaces 255, 256, 257, 258, 411. The CPU 250, ROM 251 and RAM 253, and interfaces 255 to 258 and 411 are connected by a bus 254 so as to be able to communicate with each other.

The CPU 250 executes various processes. The ROM 251 is a recording medium in which a program 252 for causing the CPU 250 to execute various processes is recorded. The RAM 253 is a storage device that temporarily stores various data such as the processing result of the CPU 250.

A control device 400 is connected to the interface 411. CPU250, each detection head ₇ to the controller 400 via the interface 411 _1, 7 _2, 9 1, ₉ transmits a _second detection result signal that becomes.

The interface 255, the detection head ₇₁ for detecting the angle of the joint is connected. The interface 256, the detection head 7 ₂ for detecting the angle of the joint is connected. Each interface 255 and 256, transmits a signal for blinking the light in the light emitting portion of the detection head ₇₁ and _{7 2} receives a signal from the light receiving portion of the detection head ₇₁ and _{7 2,} the CPU250 Output.

The interface 257, the detection head 9 ₁ for detecting the torque of the joint is connected. The interface 258, the detection head 9 ₂ for detecting the torque of the joint is connected. Each interface 257 and 258, transmits a signal for blinking the light in the light emitting portion of the detector head _{9 1} and _{9 2,} receives the signal from the light receiving portion of the detection head _{9 1} and _{9 2,} the CPU250 Output. In this way CPU250 acquires position information, the detection head ₇₁ at a predetermined time _interval, 7 _2, 9 1, _{9 2} from.

The CPU 250 functions as an angle signal processing unit and a torque signal processing unit by executing the program 252. The CPU 250 as an angle signal processing unit performs a process of obtaining _{the value of the angle of the joint J 1} , that is, the relative angle of the base member 3 with respect to the fixing member 1. The CPU 250 as a torque signal processing unit performs a process of obtaining the value of the _{torque applied to the joint J 1,} that is, the value of the torque applied between the first ring 28 of the structure 4 and the second ring 29 of the structure 4. The CPU 250 outputs these calculation results to the control device 400.

Here, the detection head 7 ₁ and 7 _2, i.e. the sensor substrate 21 may be eccentric to the rotation axis A1, which is the rotation center of the joint J1. That is, that the measurement center of the angle of the detection head ₇₁ and 7 ₂ are shifted with respect to the rotation axis A1. This deviation is called eccentric error. If there is eccentricity error, the position of the detection head 7 ₁ and 7 ₂ in accordance with rotation of the joint J1 is varied.

Let φ be the direction of this eccentric error and δ be the magnitude. Furthermore, the mounting radius of the detection head ₇₁ and 7 ₂ R, when the rotation angle of the joint and theta, the detection value s ₀ and s ₁₈₀ of the two detection heads is the following formula.

The second term of the above equation is the eccentric error. When these two equations are transformed, the rotation angle θ becomes the following equation.

_{By averaging s 0} and s ₁₈₀ as in this equation, the eccentric error can be removed at the rotation angle θ. That is, by facing the detection head 7 ₁ and 7 _2, it is possible to reduce the angle detection eccentricity error. It performs the same calculation processing for the detection head 9 ₁ and 9 _2. Then, the torque is calculated by using the rigidity value of the structure 4 from the obtained angle.

According to the present embodiment above, the detection head 9 ₁ as the detector for detecting the displacement of the structure _4, 9 _2, the processing circuit 25 provided in the sensor substrate 21, a first ring 28 of the structure 4 second It is configured to be arranged between the ring 29 and the ring 29. As a result, the space for arranging the leaf spring 30 can be utilized for arranging the detector. Further, the sensor substrate 21 has a portion of the structure 4 that projects in the radial direction of the rotation axis A1, and the sensor substrate 21 can slightly change its position in the circumferential direction of the structure 4. As a result, the position of the sensor board 21 can be easily adjusted.

The processing procedure of rotation angle detection and torque detection in the above-described embodiment has been described as being specifically executed by the CPU 250. However, a software control program capable of executing the above-mentioned functions and a recording medium on which the program is recorded may be mounted on the control device 400 or the external input device 500.

Therefore, a software control program capable of executing the above-mentioned functions, a recording medium on which the program is recorded, and a communication device constitute the present invention.

Further, in the above embodiment, the case where the computer-readable recording medium is ROM or RAM and the control program is stored in the ROM or RAM has been described, but the present invention is not limited to such a mode. Absent.

The control program for carrying out the present invention may be recorded on any recording medium as long as it is a computer-readable recording medium. For example, as a recording medium for supplying a control program, an HDD, an external storage device, a recording disk, or the like may be used.

(Other embodiments)
Further, in the above-described embodiment, the case where the robot arm main body 200 uses an articulated robot arm having a plurality of joints has been described, but the number of joints is not limited to this. Although the vertical multi-axis configuration is shown as the type of robot device, the same configuration as above can be implemented for joints of different types such as parallel link type.

Further, in the above-described embodiment, the ring shape of the annulus has been described as an example of the member that is relatively displaced in the structure 4, but the present invention is not limited to this. For example, the present invention can be carried out as long as it has a hollow structure in the shape of a rectangle or a triangle.

Further, the various embodiments described above are applied to a machine capable of automatically performing expansion / contraction, bending / stretching, vertical movement, horizontal movement or turning operation, or a combined operation thereof based on information of a storage device provided in the control device. It is possible.

The present invention is not limited to the above-described embodiment, and many modifications can be made within the technical idea of the present invention. Moreover, the effects described in the embodiments of the present invention merely list the most preferable effects arising from the present invention, and the effects according to the present invention are not limited to those described in the embodiments of the present invention.

4 Structure 7 ₁ , 7 ₂ , 9 ₁ , 9 ₂ Detection head 6 _{, 8 1} , 8 ₂ Scale 10m, 10s, 12m, 12s Bolt 21, 21m, 21s Sensor board 22m, 22s Mounting part 25 Processing circuit 26, 80a , 80b Connector 28 1st ring 29 2nd ring 30 Leaf spring 40 Opening 100 Robot device 210 Base 201-206 Link 221-226 Detection device

Claims (15)

The first part and
A second part connected to the first part via a connecting part, and
A first sensor that outputs a signal according to the relative displacement between the first part and the second part,
A substrate on which the first sensor is mounted is provided.
The substrate is provided between the first portion and the second portion.
A detection device characterized by that. In the detection device according to claim 1,
The substrate is provided with protrusions that project outward from the first portion and the second portion.
A detection device characterized by that. In the detection device according to claim 2,
A processing circuit for processing the signal of the first sensor is provided in the protrusion.
A detection device characterized by that. In the detection device according to any one of claims 1 to 3.
The substrate includes a first substrate and a second substrate, and the first sensor is provided on each of the first substrate and the second substrate.
A detection device characterized by that. In the detection device according to claim 4,
The first substrate and the second substrate are each provided with a position adjusting mechanism capable of independently adjusting the position.
A detection device characterized by that. In the detection device according to claim 5,
The position adjusting mechanism is connected to the first portion, and the first substrate and the second substrate are provided at the first portion via the position adjusting mechanism.
A detection device characterized by that. In the detection device according to any one of claims 1 to 6.
The substrate includes a second sensor that outputs a signal when the first portion or the second portion is displaced relative to a predetermined device.
The first portion includes an opening, and the second sensor is provided in the opening.
A detection device characterized by that. In the detection device according to claim 7,
The second sensor is provided on the back surface of the surface of the substrate on which the first sensor is provided.
A detection device characterized by that. In the detection device according to any one of claims 4 to 8.
A connection portion is provided for each of the first substrate and the second substrate, and the first substrate and the second substrate are electrically connected by being wired by the connection portion.
A detection device characterized by that. A drive device including the detection device according to any one of claims 1 to 9. A robot device including the detection device according to any one of claims 1 to 9. The first part and
A second part connected to the first part via a connecting part, and
A first sensor that outputs a signal according to the relative displacement between the first part and the second part,
A processing unit that processes the signal of the first sensor and
A substrate on which the first sensor is mounted is provided.
The substrate is provided between the first portion and the second portion.
The processing unit
Based on the signal output from the first sensor, the force applied to the first portion, the connecting portion, and the second portion is obtained.
A detection method characterized by that. A method for manufacturing an article, which comprises manufacturing the article using the robot device according to claim 11. A control program capable of executing the detection method according to claim 12. A computer-readable recording medium containing the control program according to claim 14.

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