KR101835728B1 - Calibration apparatus for 6-axis sensor - Google Patents

Abstract

The present invention relates to a six-axis sensor calibration device capable of performing calibration for a six-axis sensor according to the relation of values detected by the six-axis sensor to correspond to magnitudes of torque and force. According to the present invention, the six-axis sensor calibration device comprises: a base plate; a target sensor supporting unit provided to freely rotate and tilt from the base plate and supporting a target sensor to be a target for calibration; a reference sensor supporting unit which faces the target sensor supporting unit and supports a reference sensor for detecting magnitudes of torque and force applied to the target sensor; a fastening unit for fastening the target sensor supporting unit and the reference sensor supporting unit; a torque applying unit supported on the base plate, connected to the target sensor supporting unit, and applying torque to the target sensor by rotating the target sensor supporting unit about 3-axis thereof perpendicular to each other; and a force applying unit supported on the base plate, connected to the reference sensor supporting unit, and linearly operating the reference sensor supporting unit about the 3-axis thereof perpendicular to each other to apply force to the target sensor. Therefore, the six-axis sensor calibration device can secure reliability of the six-axis sensor and can precisely control equipment using the six-axis sensor.

Description

6-Axis Sensor Calibration Device {CALIBRATION APPARATUS FOR 6-AXIS SENSOR}

[0001] The present invention relates to a six-axis sensor calibration apparatus, and more particularly to a six-axis sensor calibration apparatus in which a torque that rotates about three axes orthogonal to each other and a three- Axis sensor based on the value of the 6-axis sensor calibration.

Conventional force / torque sensors mostly use a strain gauge to sense or measure force / torque.

Generally, a strain gauge sensor is composed of a pair of external connectors to which an external force is applied, an elastic body that connects a pair of external connectors, and a strain gauge attached to the elastic body to measure the deformation amount of the elastic body. The strain gauge senses or measures an external force by sensing a resistance that varies according to the amount of deformation of the elastic body deformed by the external force applied to the external connector.

Sensors using strain gauges are manufactured by bonding a plurality of strain gauges to an elastic body. In this process, manufacturing cost is increased, and after a long time, the adhesive used to bond the strain gauge is hardened, And the like.

Recently, a capacitance type 6-axis force / torque sensor having a simple structure and lowering manufacturing difficulty and improved durability has been developed. Such a capacitive six-axis force / torque sensor has already been disclosed in Korean Registered Patent No. 1477120, Capacitive 6-Axis Force / Torque Sensor, and the like.

However, even if a six-axis sensor is precisely manufactured, errors may be generated in values detected by all six-axis sensors manufactured. Therefore, before actually using the six-axis sensor, the values detected by the six-axis sensor are collected corresponding to the magnitude of the torque acting on the six-axis sensor and the magnitude of the force, and the magnitude of the torque acting on the six- The calibration of the six-axis sensor according to the correlation of the values detected by the six-axis sensor must be performed.

Korean Registered Patent No. 1477120 (Registered on December 22, 2014)

SUMMARY OF THE INVENTION It is an object of the present invention to provide a six-axis sensor calibration capable of performing calibration for a six-axis sensor according to the correlation of values detected by a six-axis sensor corresponding to the magnitude of a torque and the magnitude of a torque acting on the six- Device.

A six-axis sensor calibration apparatus according to the present invention includes: a base plate; a target sensor support unit provided to be freely rotatable and tiltable from the base plate to support a target sensor to be calibrated; A reference sensor supporting part for supporting a reference sensor for detecting a magnitude of a torque and a force acting on the base plate, a fastening part for fastening the target sensor supporting part to the reference sensor supporting part, A torque acting part which rotates the sensor supporting part about three axes orthogonal to each other to apply a torque to the target sensor and a torque acting part which is supported by the base plate and is connected to the reference sensor supporting part, Respectively, It may include a power function of applying a force to the target sensor.

Wherein the torque acting portion includes a first rotary actuator connected to the target sensor support portion and rotating the target sensor support portion about a first rotation axis disposed in the z axis direction, a first tilting plate for restricting the first rotary actuator, A second rotary actuator for rotating the first tilting plate about a second rotation axis disposed in the y-axis direction, a second tilting plate for restricting the second rotation axis, and a second rotary actuator for rotating the first tilting plate about the third rotary shaft, And a third rotary actuator for rotating the two tilting plates.

Wherein the torque acting portion is driven to rotate about the second rotation axis by the rotational power of the second rotary actuator by connecting the second rotary actuator and the second rotation shaft to restrain the first tilting plate, A first link that tilts the plate about the first rotation axis and a third link that connects the third rotary actuator and the third rotation shaft and is rotationally driven about the third rotation axis by the rotational power of the third rotary actuator, And a second link for restricting the second tilting plate to tilt the second tilting plate about the third rotation axis.

The second rotation axis and the third rotation axis intersect on the same plane, and the first rotation axis may be disposed on an extension of the intersection of the second rotation axis and the third rotation axis.

The point at which the first, second, and third rotational axes intersect is the center of the upper surface of the target sensor, and the origin of force / torque measurement of the target sensor may be a point at which the first, second, and third rotational axes intersect.

The torque applying unit may further include a safety hook coupled to the second tilting plate to limit a tilting angle of the second tilting plate to prevent breakage of the target sensor.

Wherein the force acting portion includes a first linear actuator for supporting the reference sensor support portion and linearly driving the reference sensor support portion in the z-axis direction, a second linear actuator for supporting the first linear actuator and linearly driving the first linear actuator in the y- 2 linear actuators, and a third linear actuator for supporting the second linear actuators and linearly driving the second linear actuators in the x-axis direction.

The six-axis sensor calibration apparatus according to the present invention calibrates the six-axis sensor according to the relationship between the values detected by the six-axis sensor corresponding to the magnitude of the torque and the magnitude of the torque acting on the six- And it is possible to obtain the effect of precisely controlling the equipment using the six-axis sensor.

1 is a perspective view illustrating a six-axis sensor calibration apparatus according to an embodiment of the present invention.
2 is a perspective view showing a part of a six-axis sensor calibration apparatus according to the present embodiment.
3 is an exploded perspective view showing a coupling relationship of a torque acting portion of the six-axis sensor calibration apparatus according to the present embodiment.
4 is a view for explaining the torque / force measurement origin of the 6-axis sensor calibration according to the present embodiment.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only examples of the present invention, and are not intended to represent all of the technical ideas of the present invention, so that various equivalents and modifications may be made thereto .

Hereinafter, a six-axis sensor calibration apparatus according to the present invention will be described with reference to the accompanying drawings.

2 is a perspective view illustrating a part of a six-axis sensor calibration apparatus according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of a six-axis sensor calibration apparatus according to an embodiment of the present invention. Is an exploded perspective view showing the engagement relationship of the torque acting portion of the device.

1 to 3, a six-axis sensor calibration apparatus (hereinafter, referred to as 'calibration apparatus') according to the present embodiment includes a base plate 100, a target sensor support unit 200, a reference sensor support unit 300 A coupling part 400, a torque acting part 500, and a force acting part 600. [

The base plate 100 is provided in the form of a flat plate and serves as a base for installing the calibration apparatus 1. [ The base plate 100 is supported by a plurality of frames 110 and facilities such as an industrial PC and a motor drive not shown are accommodated in the lower portion of the base plate 100. The motor drive is provided for driving the motors included in the actuators to be described later, and the industrial PC is provided for controlling the motor drives.

The target sensor support unit 200 supports the target sensor 10. The target sensor 10 may be a six-axis sensor to be subjected to calibration. The target sensor support unit 200 is provided so that the target sensor 10 can be rotated and tilted around three axes. That is, the opening 120 may be formed in the base plate 100, and the target sensor support 200 may be spaced apart from the inner surface of the opening 120 of the base plate 100.

The reference sensor support 300 supports the reference sensor 20. [ The reference sensor 20 may be a six-axis sensor for detecting the magnitude of the torque and the magnitude of the force when applying a torque or a force to the target sensor 10 for the calibration of the target sensor 10. [ The reference sensor support unit 300 is opposed to the target sensor support unit 200.

The fastening part 400 may include a lower fastening plate 410 connected to the upper surface of the target sensor 10 and an upper fastening plate 420 connected to the lower surface of the reference sensor 20. [ The upper fastening plate 420 may be provided with fastening holes 430 for fastening the upper fastening plate 420 and the lower fastening plate 410 together.

The torque applying unit 500 is connected to the target sensor supporting unit 200 to rotate the target sensor supporting unit 200 about the three axes to apply torque to the target sensor supporting unit 200 about the three axes orthogonal to each other . That is, the torque acting portion 500 may include a first rotary actuator 510, a second rotary actuator 520, and a third rotary actuator 530.

The first rotary actuator 510 is connected to the target sensor support 200. The first rotary actuator 510 includes a first rotary shaft 511 disposed in the z-axis direction and rotated about the z-axis. The first rotation shaft 511 is fastened to the target sensor support 200. The first rotary actuator 510 rotates the target sensor support 200 about the first rotary shaft 511.

As a result, the first rotary actuator 510 generates rotational power about the z-axis, and the rotational power is transmitted to the target sensor support 200 to apply a torque to the target sensor 10 about the z axis .

The second rotary actuator 520 is supported on the lower surface of the base plate 100. The second rotary actuator 520 may be disposed in the x-axis direction. A second rotary shaft 521 disposed in the x-axis direction may be disposed above the base plate 100. The second rotary actuator 520 may be connected to a first link 522 for transmitting rotational power of the second rotary actuator 520. One end of the first link 522 may be connected to the output end of the second rotary actuator 520 and the other end of the first link 522 may be connected to the second rotation shaft 521.

A first tilting plate 523 is disposed below the target sensor support 200 to transmit the rotational power of the first rotary actuator 510 transmitted from the first link 522 to the target sensor support 200 . The first tilting plate 523 may be spaced apart from the lower surface of the target sensor support 200 so that the first tilting plate 523 can be tilted separately from the target sensor support 200. A through hole 523a through which the first rotary actuator 510 passes may be formed at the center of the first tilting plate 523 and the first rotary actuator 510 may be fastened to the first tilting plate 523. [ A first link insertion groove 523b is formed in the side surface of the first tilting plate 523 to receive the first link 522. The first link 522 is inserted into the first link insertion groove 523b, 1 tilting plate 523 is restrained.

Accordingly, when rotational power is generated by the second rotary actuator 520, the first link 522 is rotated about the first rotation axis 511 arranged in the x-axis direction. As the first link 522 is rotated, the first tilting plate 523 constrained to the first link 522 is tilted together with the first link 522. As the first tilting plate 523 is tilted, the first rotary actuator 510 is tilted together with the first tilting plate 523. As the first rotary actuator 510 is tilted, the target sensor support 200 fastened to the first rotary actuator 510 is tilted together with the first rotary actuator 510.

As a result, the second rotary actuator 520 generates rotational power about the x-axis, and this rotational power is transmitted to the target sensor support 200 and is transmitted to the target sensor 10 about the x- .

The third rotary actuator 530 is supported on the lower surface of the base plate 100. The third rotary actuator 530 may be disposed in the y-axis direction. A third rotary shaft 531 disposed in the y-axis direction may be disposed on the upper side of the base plate 100. The third rotary actuator 530 may be connected to a second link 532 for transmitting rotational power of the third rotary actuator 530. One end of the second link 532 may be connected to the output end of the third rotary actuator 530 and the other end of the second link 532 may be connected to the third rotation shaft 531.

A second tilting plate 533 is provided around the target sensor support 200 to transmit the rotational power of the third rotary actuator 530 transmitted from the second link 532 to the target sensor support 200 . The second tilting plate 533 may be spaced apart from the side surface of the target sensor support 200 so that the second tilting plate 533 can be independently tilted with respect to the target sensor support 200 and the first tilting plate 523. A bearing 534 for supporting the second rotation shaft 521 may be provided on the second tilting plate 533. A second link insertion groove 533a into which the second link 532 is inserted is formed on a side surface of the second tilting plate 533 and a second link 532 is inserted into the second link insertion groove 533a, 2 tilting plate 533 is restrained.

Accordingly, when rotational power is generated by the third rotary actuator 530, the second link 532 is rotated around the third rotational axis 531 arranged in the y-axis direction. As the second link 532 is rotated, the second tilting plate 533 constrained to the second link 532 is tilted together with the second link. As the second tilting plate 533 is tilted, the bearing 534 is tilted together. The second rotary shaft 521 is tilted together with the bearing 534 as the bearing 534 is tilted. As the second rotation shaft 521 is tilted, the first link 522 is tilted together with the second rotation shaft 521. The first tilting plate 523 constrained to the first link 522 is tilted together with the first link 522 as the first link 522 is tilted. As the first tilting plate 523 is tilted, the first rotary actuator 510 is tilted together with the first tilting plate 523. As the first rotary actuator 510 is tilted, the target sensor support 200 fastened to the first rotary actuator 510 is tilted together with the first rotary actuator 510.

As a result, the third rotary actuator 530 generates rotational power about the y-axis, and the rotational power is transmitted to the target sensor support 200 to apply a torque to the target sensor 10 about the y-axis .

The first rotary actuator 510, the second rotary actuator 520, and the third rotary actuator 530 may be a rotary actuator including a combination of a rotary motor and a speed reducer.

On the other hand, the torque acting portion 500 may include a safety catch jaw 535. The safety catching jaw 535 may be coupled to the lower surface of the second tilting plate 535. [ The second tilting plate 533 is tilted at an excessive angle so as to prevent the target sensor 10 from being interfered with and broken by other elements as the second tilting plate 533 is tilted at an excessive angle, The tilting angle of the second tilting plate 533 is restricted by acting on the base plate 100 to be tilted.

The force application unit 600 is connected to the reference sensor support unit 300 to apply a force to the target sensor support unit 200 in three mutually orthogonal axes, And linearly drives the target sensor 10 in three directions. That is, the force application unit 600 may include a first linear actuator 610, a second linear actuator 620, and a third linear actuator 630.

The first linear actuator 610 supports the reference sensor support unit 300 and linearly drives the reference sensor support unit 300 in the z-axis direction. As the first linear actuator 610 linearly drives the reference sensor support unit 300 in the z axis direction, the first linear actuator 610 applies a force to the target sensor support unit 200 fastened to the reference sensor support unit 300 by the fastening unit 400 in the z- A force in the z-axis direction acts on the target sensor 10 as a result.

The second linear actuator 620 supports the first linear actuator 610 and linearly drives the first linear actuator 610 in the y-axis direction. As the second linear actuator 620 linearly drives the first linear actuator 610 in the y axis direction, the reference sensor support 300 supported by the first linear actuator 610 is linearly driven in the y axis direction, The force in the y-axis direction acts on the target sensor support unit 200 fastened to the reference sensor support unit 300 by the fastening unit 400 and consequently a force in the y-axis direction acts on the target sensor 10.

The third linear actuator 630 supports the second linear actuator 620 and linearly drives the second linear actuator 620 in the x-axis direction. As the third linear actuator 630 linearly drives the second linear actuator 620 in the x-axis direction, the second linear actuator 620 is linearly driven in the x-axis direction. As the second linear actuator 620 linearly drives in the x-axis direction, the first linear actuator 610 supported by the second linear actuator 620 is linearly driven in the x-axis direction. As the first linear actuator 610 is linearly driven in the x-axis direction, the reference sensor supporter 300 supported by the first linear actuator 610 is linearly driven in the x-axis direction, A force in the x-axis direction acts on the target sensor support unit 200 fastened to the sensor support unit 300 and consequently a force in the x-axis direction acts on the target sensor 10.

As the first linear actuator 610, the second linear actuator 620, and the third linear actuator 630, a linear actuator including a combination of a rotary motor, a ball screw, and a linear block may be used.

As described above, the six-axis sensor calibration apparatus 1 according to the present embodiment can apply a torque in three axial directions to a target sensor 10 to be calibrated and exert a force in three axial directions.

Meanwhile, the origin P for measuring the torque / force of the six-axis sensor calibration apparatus according to the present embodiment may be an intersection point where the first, second and third rotary shafts 511, 521 and 531 intersect with each other.

4 is a view for explaining the torque / force measurement origin of the 6-axis sensor calibration according to the present embodiment.

4, the six-axis sensor calibration apparatus 1 according to the present embodiment is a six-axis sensor calibration apparatus according to the present embodiment, in which a measurement origin P of a force / And is formed at the center of the upper surface. This is because if the first, second and third rotary shafts 511, 521 and 531 do not intersect with each other and any one of the rotary shafts is dispersed with the other rotary shafts in torque or force to the object sensor 10, The position of the target sensor 10 can be varied and the reliability of the values detected from the target sensor 10 can not be ensured as the position of the target sensor 10 is varied to be.

The second rotation axis 521 and the third rotation axis 531 intersect on the same plane as the upper surface of the target sensor 10 and the first rotation axis 511 intersects the second rotation axis 521 and the third rotation axis 531, Are preferably arranged on extension lines of intersecting intersection points. At this time, the points where the first, second, and third rotary shafts 511, 521, and 531 intersect can be the center of the upper surface of the target sensor 10.

Hereinafter, the operation of the six-axis sensor calibration apparatus according to the present embodiment will be described.

First, the target sensor 10 to be calibrated is supported by the target sensor support unit 200, and the reference sensor 20 that detects the magnitude of the torque acting on the target sensor 10 and the magnitude of the force, (Not shown). The lower fixing plate 410 is fastened to the upper surface of the target sensor supporting part 200 and the upper fastening plate 420 is fastened to the lower surface of the reference sensor supporting part 300.

Subsequently, the position of the reference sensor support unit 300 with respect to the target sensor support unit 200 is aligned. That is, the user operates the second linear actuator 620 and the third linear actuator 630 so that the reference sensor support unit 300 is positioned above the target sensor support unit 200, (20). When the positions of the target sensor 10 and the reference sensor 20 are aligned as described above, the user descends the reference sensor support portion 300 using the first linear actuator 610, The plate 410 can be fastened.

Subsequently, in order to calibrate the target sensor 10, a torque can be applied to the target sensor 10 around the three axes, and a force can be applied in three axial directions.

At this time, the reference sensor 20 detects the magnitude (Tx, Ty, Tz) and the magnitude (Fx, Fy, Fz) of the torque acting on the target sensor 10, Capacitances Ctx, Cty and Ctz corresponding to the magnitudes Tx, Ty and Tz of the torque detected in the reference sensor 20 and magnitudes Fx, Fy and Fz (Cfx, Cfy, Cfz) corresponding to the capacitance (Cfx, Cfy, Cfz).

The six-axis sensor calibration apparatus according to the present embodiment detects the detected value of the target sensor 10 according to the torque / force magnitude (Tx, Ty, Tz, Fx, Fy, Fz) detected by the reference sensor 20 (Tx, Ty, Tz, Fx, Fy, and Fz) detected by the reference sensor 20, The calibration of the target sensor 10 can be performed based on the correlation of the detection values Ctx, Cty, Ctz, Cfx, Cfy, and Cfz.

The embodiments of the present invention described above and shown in the drawings should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is limited only by the matters described in the claims, and those skilled in the art will be able to modify the technical idea of the present invention in various forms. Accordingly, such improvements and modifications will fall within the scope of the present invention as long as they are obvious to those skilled in the art.

1: 6 axis sensor calibration device
10: target sensor 20: reference sensor
100: base plate 200: target sensor support
300: reference sensor supporting part 400: fastening part
500: torque acting portion 510: first rotary actuator
511: first rotating shaft 520: second rotary actuator
521: second rotating shaft 522: first link
523: first tilting plate 530: third rotary actuator
531: Third rotating shaft 532: Second link
533: second tilting plate 600: force acting portion
610: first linear actuator 620: second linear actuator
630: third linear actuator

Claims (7)

A base plate;
A target sensor support member spaced apart from the base plate so as to freely rotate and tilt from the base plate and supporting an object sensor to be a target for calibration;
A torque acting portion supported on the base plate and connected to the target sensor support portion to rotate the target sensor support portions around three mutually orthogonal axes to apply a torque to the target sensor;
A reference sensor support unit for supporting a reference sensor for detecting a magnitude of a torque and a force acting on the target sensor, the target sensor being opposed to the target sensor support unit;
A fastening part for fastening the reference sensor supported by the reference sensor support part to the object sensor supported by the object sensor support part;
And a force acting portion supported on the base plate and connected to the reference sensor support portion to linearly drive the reference sensor support portions in three mutually orthogonal axes to apply a force to the target sensor. Sensor calibration device. The method according to claim 1,
The torque acting portion
A first rotary actuator connected to the target sensor support unit and rotating the target sensor support unit about a first rotation axis disposed in the z axis direction;
A first tilting plate for restricting the first rotary actuator;
a second rotary actuator for rotating the first tilting plate about a second rotation axis disposed in the x-axis direction;
A second tilting plate for restricting the second rotation axis;
and a third rotary actuator for rotating the second tilting plate about a third rotation axis disposed in the y-axis direction. 3. The method of claim 2,
The torque acting portion
The second rotary actuator is connected to the second rotary shaft and is rotationally driven about the second rotary shaft by the rotational power of the second rotary actuator to restrain the first tilting plate, A first link for tilting about a rotational axis; And
The second rotary actuator rotates about the third rotary shaft by the rotational power of the third rotary actuator by connecting the third rotary actuator and the third rotary shaft and restrains the second tilting plate, And a second link for tilting about a third rotational axis. The method of claim 3,
The second rotary shaft and the third rotary shaft intersect on the same plane,
Wherein the first rotation axis is disposed on an extension of an intersection of the second rotation axis and the third rotation axis. 5. The method of claim 4,
A point at which the first, second, and third rotational axes intersect is a center of an upper surface of the target sensor,
Wherein the origin of the force / torque measurement of the target sensor is a point at which the first, second, and third rotational axes intersect. The method of claim 3,
The torque acting portion
And a second tilting plate protruding from the second tilting plate so as to be caught by the base plate when the second tilting plate exceeds a predetermined tilting angle to limit the tilting angle of the second tilting plate, Axis sensor calibration device. The method according to claim 1,
The force-
A first linear actuator for supporting the reference sensor supporter and linearly driving the reference sensor supporter in a z-axis direction;
A second linear actuator for supporting the first linear actuator and linearly driving the first linear actuator in the y-axis direction;
And a third linear actuator for supporting the second linear actuator and linearly driving the second linear actuator in the x-axis direction.

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