KR20230133015A - Apparatus and method for compensating for deflection of a manipulator using an tilt sensor - Google Patents

Abstract

A compensation device is provided. The compensation device includes a measuring unit that obtains measured values from a tilt sensor installed on a robot arm; a calculation unit that estimates the amount of deflection of the robot arm using the measured value; It may include a compensator that compensates for the amount of deflection.

Description

Apparatus and method for compensating for deflection of a manipulator using an tilt sensor}

The present invention relates to an apparatus and method for compensating for deflection of a manipulator.

Robots are used for various purposes in many industries. To achieve various purposes, various work tools for picking up, welding, or cutting objects may be installed at the end of the robot arm.

To achieve precision in various tasks, work tools need to be placed accurately in the designed control position. However, static errors such as deflection may occur due to the work tool's own weight or the load applied to the work tool.

For normal use of the robot, this deflection needs to be compensated.

Korean Patent Publication No. 1198179 discloses a technology to minimize the deflection angle of the end effector through simple mechanism correction by inserting a thin plate into each joint of a robot arm and assembling it so that the joint faces upward from the horizontal plane.

Korean Patent Publication No. 1198179

The present invention is to provide a compensation device and method for compensating for the deflection of a work tool such as a manipulator using a tilt sensor.

The compensation device of the present invention includes a measuring unit that obtains measured values from a tilt sensor installed on a robot arm; a calculation unit that estimates the amount of deflection of the robot arm using the measured value; It may include a compensator that compensates for the amount of deflection.

The measurement unit may obtain at least one of a first measurement value, a second measurement value, and a third measurement value. The first measurement value may be a value measuring the inclination of a link corresponding to a joint of the robot arm and a node between the joints, and the second measurement value may be a value measuring the inclination of the joint. The third measurement value may be a value obtained by measuring the inclination of a work tool provided at the end of the robot arm.

The calculation unit estimates the amount of deflection of the link using the first measurement value, estimates the amount of deflection of the joint using the second measurement value, or estimates the amount of deflection of the work tool using the third measurement value. can do.

The calculation unit may calculate at least one of a first theoretical value, a second theoretical value, and a third theoretical value using the control value of the robot.

The first theoretical value may include a slope value of the link calculated using the control value.

The second theoretical value may include a tilt value of the joint calculated using the control value.

The third theoretical value may include a tilt value of the work tool calculated using the control value.

The calculation unit estimates the difference between the first measurement value and the first theoretical value as the amount of deflection of the link, estimates the difference between the second measurement value and the second theoretical value as the amount of deflection of the joint, or estimates the difference between the first measurement value and the second theoretical value as the amount of deflection of the joint. The difference between the measured value and the third theoretical value can be estimated as the amount of deflection of the work tool.

The measuring unit may obtain a measurement value from a tilt sensor installed at an end on the work tool side of the second link forming the robot arm or installed on a third joint at the end on the work tool side of the second link.

The compensator may control a module that moves the second link around a joint that is spaced apart from the second link and located upstream of the second link in order to compensate for an error in the measured value with respect to the theoretical value.

The measuring unit may obtain a measurement value from a tilt sensor installed at an end on the work tool side of the second link forming the robot arm or installed on a third joint at the end on the work tool side of the second link.

In order to compensate for the error of the measured value with respect to the theoretical value, the compensator is disposed at an end immediately in front of the second link and uses a first joint at the end of the robot body side of the first link to be rotatably connected to the second link. The module that moves the first link to the center can be controlled.

An error in the measured value of the second link or the third joint relative to the theoretical value may be compensated by the movement of the first link.

The measuring unit may obtain a tilt measurement value of a second link rotatably connected to a work tool side end of the first link forming the robot arm.

The compensator may maintain the rotation angle of the second link with respect to the first link in its current state.

The compensator measures the tilt with respect to the second link while rotating the first link around a joint located upstream of the first link while maintaining the rotation angle of the second link with respect to the first link. The value may be matched to a theoretical value for the second link.

When the robot arm is formed by connecting a plurality of links through a joint structure, the measuring unit may initially acquire the inclination of an upstream link closer to the body of the robot among the plurality of links.

The compensation unit may compensate for the amount of deflection of the upstream link.

After the amount of deflection of the upstream link is compensated, the measuring unit may acquire the inclination of the downstream link whose inclination has changed due to compensation of the amount of deflection of the upstream link.

The compensation unit may compensate for the amount of deflection of the downstream link when the amount of deflection of the upstream link is compensated and the slope of the downstream link is obtained.

The compensator may feedback control the amount of deflection of the robot arm using the measured value.

The compensation device of the present invention includes a tilt sensor installed on a support supporting a target; It may include a compensator that compensates for the amount of deflection of the target using the measured value of the tilt sensor installed on the support.

The compensation unit may correct the inclination of the support in a direction in which the measured inclination value of the support follows a previously calculated theoretical value.

The compensator may obtain only the first angle in the direction of gravity among the rotation angles of the posture calculated by forward kinematics.

The compensator may obtain a second angle of the direction of gravity measured by the tilt sensor.

The compensation unit may compensate for the difference between the first angle and the second angle.

The compensation method of the present invention includes a measurement step of acquiring measured values from a tilt sensor installed on the robot arm; It may include a compensation step of compensating for the amount of deflection of the robot arm using the measured value.

The compensation device of the present invention can measure the mechanical deflection of the target using a tilt sensor. The compensation device calculates the deviation between the measured tilt value and the theoretical value, and uses a compensation algorithm that takes the deviation value as an input to the module. The above deviation can be converged to zero by activating . Through this process, the amount of target deflection can be compensated and difficulties in target control can be alleviated.

According to the present invention, the amount of target deflection is compensated using a tilt sensor, so stiffness analysis for deflection compensation is unnecessary. Due to the exclusion of stiffness analysis, the process of calculating the deflection amount of the target is simplified, and the accuracy of calculating the deflection amount can be improved.

According to the present invention, realistic and accurate correction of the non-linear factor of the theoretical stiffness value is possible.

The compensation device of the present invention can compensate for the amount of sagging of targets such as robot arms, manipulators, work tools, etc. due to tolerance, self-weight, etc. As a result, the compensation device of the present invention can compensate for the amount of deflection through a measured value of the inclination of the target with respect to the ground.

In particular, the compensation device of the present invention can compensate in real time for the amount of deflection of the work tool due to the weight of the work object lifted into the air by the robot arm.

The compensation device of the present invention is capable of calculating and compensating for real-time deviation of the yarn deflection amount of the work tool.

The compensation device of the present invention can be used for calibration of axis alignment at the shipping stage of a robot arm equipped with a work tool.

1 is a schematic diagram showing a compensation device of the present invention.
Figure 2 is a schematic diagram showing the robot arm as a wire frame.
Figure 3 is a schematic diagram showing the operation of the compensator.
Figure 4 is a schematic diagram showing a robot arm in which the amount of deflection of a work tool is compensated by the compensation device of the present invention.
Figure 5 is a flowchart showing the compensation method of the present invention.
6 is a diagram illustrating a computing device according to an embodiment of the present invention.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

In this specification, duplicate descriptions of the same components are omitted.

Also, in this specification, when a component is mentioned as being 'connected' or 'connected' to another component, it may be directly connected or connected to the other component, but may be connected to the other component in the middle. It should be understood that may exist. On the other hand, in this specification, when it is mentioned that a component is 'directly connected' or 'directly connected' to another component, it should be understood that there are no other components in between.

Additionally, the terms used in this specification are merely used to describe specific embodiments and are not intended to limit the present invention.

Also, in this specification, singular expressions may include plural expressions, unless the context clearly dictates otherwise.

In addition, in this specification, terms such as 'include' or 'have' are only intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and one or more It should be understood that this does not exclude in advance the presence or addition of other features, numbers, steps, operations, components, parts, or combinations thereof.

Also, in this specification, the term 'and/or' includes a combination of a plurality of listed items or any of the plurality of listed items. In this specification, 'A or B' may include 'A', 'B', or 'both A and B'.

Additionally, in this specification, detailed descriptions of well-known functions and configurations that may obscure the gist of the present invention will be omitted.

Figure 1 is a schematic diagram showing the compensation device 100 of the present invention.

Work tools such as manipulators, machines, cutters, welders, grippers, and suction machines installed at the end of the robot arm 10 need to be accurately controlled to lift or process various objects. A control unit 90 that controls the robot arm 10 to control the work tool may be provided in the compensation device 100 or may be provided in a robot equipped with the robot arm 10.

In addition, it is advisable to additionally provide means for compensating for the amount of deflection d shown in FIG. 3. The amount of deflection d may be generated by the self-weight of the robot arm 10, the weight of the work object lifted by the robot arm 10, and the tolerance of a plurality of links and joints forming the robot arm 10. When a target such as a work tool has an angle different from the control value, the deflection amount d may represent the difference between the other angle and the control value.

When the amount of deflection d occurs, in reality, not only the change in angle to the target but also the change in position is reflected, and the amount of deflection d appearing in this specification may mainly represent the change in angle.

In Figure 3, the deviation between the control value of the work tool and the sagging state value is exaggerated, but in reality, it may appear insignificant. However, a change in the angle with respect to the ground, that is, a change in the inclination of the work tool based on the direction of gravity g, the ground, the robot, etc. (hereinafter referred to as 'ground'), can have a large impact on the work object even if the amount of change is small. You can. For example, if the work tool is a manipulator that supports and lifts a work object, if the manipulator is tilted even slightly, the work object placed on the manipulator may slip and fall. Therefore, it is good that at least the inclination of the work tool is as identical as possible to the inclination indicated by the control value.

Accordingly, the deflection amount d shown in FIG. 3 may mainly represent the difference between the theoretical value of the inclination of the work tool included in the control value and the actual inclination between the work tools.

In order to compensate for the tilt deflection amount d, the compensation device 100 shown in FIG. 1 may include a measurement unit 110, a calculation unit 130, and a compensation unit 150.

The measurement unit 110 may obtain measured values from a tilt sensor installed on the robot arm 10 (arm).

The calculation unit 130 may estimate the amount of deflection of the robot arm 10 using the measured value of the tilt sensor.

The compensation unit 150 may compensate for the amount of deflection estimated by the calculation unit 130. The compensation result of the compensation unit 150 may be transmitted to the control unit 90 that controls the robot arm 10. The control unit 90 may control the robot arm 10 so that the deflection amount of the work tool converges to zero according to the compensation result. In other words, the control unit 90 can control the robot arm 10 so that the measured value of the target, such as a work tool, follows the theoretical value.

When the robot arm 10 is controlled using only theoretical values excluding measured values, there is a problem in that it is difficult to adaptively respond to the amount of deflection caused by the constantly changing weight of the work object. However, according to the measuring unit 110, the calculating unit 130 can estimate the amount of deflection of the work tool in real time through a tilt sensor. Additionally, the amount of deflection caused by the weight of the work object can be compensated for in real time by the compensator 150. As a result, the compensation device 100 of the present invention can adaptively compensate in real time not only for the self-weight and tolerance of the robot arm 10, but also for the amount of deflection caused by the weight of the work object.

The measurement unit 110 may obtain at least one of a first measurement value, a second measurement value, and a third measurement value.

The first measurement value may include a value measuring the inclination of a link corresponding to a joint of the robot arm 10 (arm) and a node between the joints.

The second measurement value may include a value measuring the tilt of the joint. A joint can rotate about its axis. At this time, an imaginary line extending perpendicular to the axis of the joint and crossing the axis of the joint may be assumed. The virtual line can be rotated together with the joint. The inclination of the joint may include the angle of the corresponding virtual line with respect to the ground.

The third measurement value may include a value obtained by measuring the inclination of the work tool provided at the end of the robot arm 10. The baseline of the work tool can be established in advance. At this time, the inclination of the work tool may mean the angle and rotation angle of the corresponding reference line with respect to the ground.

The calculation unit 130 may estimate the amount of deflection of the link using the first measurement value. Alternatively, the calculation unit 130 may estimate the amount of deflection of the joint using the second measurement value. Alternatively, the calculation unit 130 may estimate the amount of deflection of the work tool using the third measurement value.

The calculation unit 130 may calculate at least one of the first theoretical value, the second theoretical value, and the third theoretical value using the control value of the robot. The control value may include a value corresponding to the measured value of the tilt sensor. At this time, among the control values, the value corresponding to the measured value of the tilt sensor may correspond to the theoretical value. For example, if the measured value of the tilt sensor is a tilt with respect to the ground or the direction of gravity, the theoretical value may also include the tilt with respect to the ground or the direction of gravity or may include a value that can be converted to the corresponding tilt.

The first theoretical value may include a slope value of the link calculated using the control value.

The second theoretical value may include a tilt value of the joint calculated using the control value.

The third theoretical value may include a tilt value of the work tool calculated using the control value.

The control value may include values that can be converted to the corresponding theoretical value instead of the first theoretical value, the second theoretical value, and the third theoretical value. At this time, the calculation unit 130 may calculate the first theoretical value, the second theoretical value, and the third theoretical value using regular kinematics.

Forward kinematics is the orthogonal function of an end-effector or work tool, given a set of joint angles (q(0), q(1), ..., q(n-1)). It is a problem of finding coordinate position (px, py, pz) and attitude (ψ, θ, ψ), and is relatively simple compared to inverse kinematics. A solution to regular kinematics can be calculated using a homogeneous transform.

Coordinates used by the compensator 150 may target a three-dimensional space formed by three coordinate axes, x-axis, y-axis, and z-axis, which are orthogonal to each other. At this time, the ground may be parallel to the x-axis and parallel to the y-axis. So to speak, the ground may correspond to the xy plane. The direction of gravity may be parallel to the z-axis direction. The position px on Cartesian coordinates may correspond to the x-axis coordinate. The position py on Cartesian coordinates may correspond to the y-axis coordinate. The position pz on Cartesian coordinates may correspond to the z-axis coordinate.

Posture ϕ may represent a rotation angle with the x-axis as the center of rotation.

Posture θ may represent a rotation angle with the y-axis as the center of rotation.

Posture ψ may represent a rotation angle with the z-axis as the center of rotation.

In particular, the calculation unit 130 and the compensation unit 150 calculate the angle (rotation angle) in the direction of gravity, that is, the rotation angle centered on at least one of the x-axis and the y-axis, as measured values and theories related to deflection compensation. It can be used as a value.

The calculation unit 130 can extract and calculate various theoretical values by analyzing the control values.

The calculation unit 130 may estimate the difference between the first measured value and the first theoretical value as the amount of deflection of the link with respect to the intermediate direction g. Alternatively, the calculation unit 130 may estimate the difference between the second measured value and the second theoretical value as the amount of joint deflection. Alternatively, the calculation unit 130 may estimate the difference between the third measured value and the third theoretical value as the amount of deflection of the work tool.

Figure 2 is a schematic diagram showing the robot arm 10 as a wire frame. Figure 2 may show a state in which the amount of deflection is included.

The robot arm 10 of FIG. 2 may include 1 axis, link 1, 2 axis, link 2, 3 axis, link 3, 4 axis, link 4, 5 axis, link 5, 6 axis, link 6, and flange. there is.

Axis 1 can be fixed to the body of the robot. If the body is fixed to the ground, it is safe to say that axis 1 is fixed to the ground.

Link 1 may be formed to be rotatable around one axis.

The second axis may be formed at the end of link 1.

Link 2 may be formed to be rotatable around two axes.

The third axis may be formed at the end of link 2.

Link 3 may be formed to be rotatable around three axes.

The fourth axis may be formed at the end of link 3.

Link 4 may be formed to be rotatable around 4 axes.

The 5th axis may be formed at the end of link 4.

Link 5 may be formed to be rotatable around 5 axes.

Axis 6 may be formed at the end of link 5.

Link 6 may be formed to be rotatable around 6 axes.

A work tool may be fixed to the flange. According to this, the inclination of the flange may be the same as the inclination of the work tool. In Figure 2 the flange may be identical to the work tool in terms of inclination.

The measurement unit 110 obtains the measured value of a tilt sensor installed at the work tool side end of the second link k2 forming the robot arm 10, or is installed at the third joint f at the work tool side end of the second link k2. Measurements from the tilt sensor can be obtained.

The compensator 150 may control a module that moves the second link around a joint that is spaced apart from the second link and located upstream of the second link in order to compensate for an error in the measured value with respect to the theoretical value. The robot arm 10 may have a joint structure in which a plurality of links are connected to each other. At this time, when a plurality of links are selected from among a plurality of links connected in series, a link closer to the body of the robot among the selected links may be referred to as a link disposed upstream. Among the selected links, the link that is farthest from the robot's body side may be referred to as a link disposed downstream.

In the case of FIG. 2, the second link may include a specific link having at least two other links (including a body or fixed link connected to one joint) on the upstream side. In Figure 2, the second link that satisfies the condition may be one of link 2, link 3, link 4, link 5, and link 6.

Figure 3 is a schematic diagram showing the operation of the compensator 150.

In order to compensate for the amount of deflection d of the second link k2, the compensator 150 may move only the second link k2 while leaving the link disposed upstream of the second link k2 as is.

As an example, the first link k1 may be connected to the end immediately in front of the second link k2 through the second joint x2. At this time, the amount of deflection d of the second link k2 can be compensated through the process of rotating the second link k2 by (-d) around the second joint x2. At this time, the deflection amount d may mean the rotation angle of the gravity direction g.

Of course, the amount of deflection can be resolved through this method as well. However, compensation for the position of the work tool, whose overall position is lowered along the direction of gravity due to deflection, is not achieved. This may mean that the work tool may deviate significantly from the position included in the control value.

When sagging problems occur, small changes at the root (upstream side) often cause significant changes in position at the distal end. Using these characteristics, a method can be devised to additionally compensate for the lowering of the target in addition to compensating for the amount of deflection of the target.

As an example, when compensating for the amount of deflection of the second link k2, the compensation unit 150 may compensate for the amount of deflection of the link disposed at the previous end rather than at the immediately preceding end. In other words, the compensator 150 can compensate for the amount of deflection by rotating the so-called root link and at the same time compensate for the position of the second link lowered due to the deflection.

As an example, the compensator 150 may not rotate the second link k2 with respect to the first link k1 in order to compensate for the amount of deflection of the second link k2. Instead, the compensator 150 may rotate the first link k1 based on the fixed axis or the body to compensate for the amount of deflection of the second link k2.

In order to compensate for the error of the measured value with respect to the theoretical value, the compensator 150 is disposed at the end immediately in front of the second link k2 and is located at the end of the robot body side of the first link k1 rotatably connected to the second link k2. 1 The module that moves the first link k1 around joint x1 can be controlled. At this time, the module may include an actuator such as a motor that rotates the first link k1 around the first joint x1.

An error in the measured value of the second link k2 or the third joint g with respect to the theoretical value may be compensated by the movement of the first link k1.

The process of compensating for the amount of deflection d by the movement of the first link k1 can be explained from another perspective as follows.

The measurement unit 110 may obtain a tilt measurement value of the second link k2 rotatably connected to the work tool side end of the first link k2 forming the robot arm 10.

The compensator 150 may maintain the rotation angle a of the second link k2 with respect to the first link k1 in its current state.

The compensator 150 may rotate the first link k1 around a joint located upstream of the first link k1 while maintaining the rotation angle a of the second link k2 with respect to the first link k1. At this time, the joint located upstream of the first link k1 may include the first joint x1 formed at the body side end of the first link k1. Alternatively, the joint located upstream of the first link k1 may include a joint formed at an end of another link upstream and spaced apart from the first link k1.

The compensator 150 may rotate the first link k1 and match the tilt measurement value for the second link k2 to the theoretical value for the second link. In other words, the compensation unit 150 may compensate for the amount of deflection of the second link k2 by rotating the upstream first link k1 instead of the second link k2.

However, if the deflection amount d of the second link k2 is compensated only by the movement of the first link k1, a problem may occur in which the position of the second link k2 in the direction of gravity increases rather than the control value, as shown in FIG. 3.

In order to compensate for the amount of deflection d of the target, such as the second link and the work tool, while allowing the target's position in the direction of gravity to follow the control value, a method may be prepared to move each of the plurality of links connected to the front end of the target little by little. In this case, a decision problem may arise as to whether to move multiple links simultaneously or sequentially. Additionally, when it is decided to move a plurality of links sequentially, an additional problem may arise regarding the order in which the plurality of links will be moved.

Considering the phenomenon that a slight movement on the root side (body side) has a large effect on the distal end, it may be advantageous for the upstream link to move first and then the downstream link to move.

As an example, the robot arm 10 may be formed by connecting a plurality of links in a joint structure.

At this time, the measuring unit 110 may initially acquire the slope of the upstream link closest to the body of the robot among the plurality of links. To this end, some of the tilt sensors among the plurality of tilt sensors may be installed in the upstream link.

Additionally, the compensation unit 150 may compensate for the amount of deflection of the upstream link using the obtained inclination of the upstream link. The control unit 90 may move the link related to the compensation of the amount of deflection of the upstream link in accordance with the compensation of the amount of deflection. Accordingly, the deflection of the upstream link can be compensated. When the amount of deflection of the upstream link is physically compensated by the control unit, the inclination and amount of deflection of the downstream link may be different compared to the initial amount.

After the amount of deflection of the upstream link is compensated, the measuring unit 110 may acquire the inclination of the downstream link whose inclination has changed due to the compensation of the amount of deflection of the upstream link. To this end, some of the tilt sensors among the plurality of tilt sensors may be installed in the downstream link.

The compensation unit 150 may compensate for the amount of deflection of the downstream link when the amount of deflection of the upstream link is compensated and the slope of the downstream link is obtained. The control unit 90 may move the link related to compensation for the amount of deflection of the downstream link according to the compensation result of the compensation unit 150. Accordingly, the deflection of the downstream link can be physically compensated.

Ultimately, the final target for which the amount of deflection is compensated can be a work tool. However, according to this embodiment, at least some of the upstream links disposed upstream of the work tool may also be targets for which the amount of deflection is compensated.

The amount of deflection of the upstream link and the amount of deflection of the downstream link may appear greatest at the work tool side end of each link. Therefore, the tilt sensor is preferably installed at the work tool side end of the upstream link or downstream link.

According to this embodiment, the amount of deflection of each link can be compensated to follow the gravity direction position of the control value indicated by a solid line in FIG. 3.

Compensation for the amount of deflection of each link can be feedback controlled using a tilt sensor. In other words, the compensator 150 can feedback control the amount of deflection of the robot arm 10 using the measured value.

Figure 4 is a schematic diagram showing the robot arm 10 in which the deflection of the work tool is compensated by the compensation device 100 of the present invention. The robot arm 10 of FIG. 4 may represent a state after the compensation device 100 of the present invention intervenes in the robot arm 10 of FIG. 3.

The compensation unit 150 of the present invention can compensate for the amount of deflection of the work tool. Additionally, the compensation unit 150 of the present invention can compensate for the amount of deflection of each link. Through this, each link, each joint, and flange forming the robot arm 10 of FIG. 4 can track the deflection amount that follows the control value and the position in the direction of gravity.

In summary, the compensation device 100 of the present invention may include a tilt sensor installed on a support that supports the target, and a compensation unit 150 that compensates for the amount of deflection of the target using the measured value of the tilt sensor installed on the support. The target may include a work tool, or it may include links or joints that form the robot arm 10. The support may include an upstream link supporting the target.

The compensation unit 150 may correct the inclination of the support in a direction in which the measured inclination value of the support follows a previously calculated theoretical value.

In order to compensate for the amount of deflection of the target and at the same time the change in position in the direction of gravity caused by the deflection, the compensation unit 150 of the present invention compensates for the amount of deflection of the support supporting the target instead of directly compensating for the amount of deflection of the target. can be taken.

At this time, the compensator 150 may obtain only the first angle of the gravity direction g among the rotation angles of the posture calculated by forward kinematics. The first angle may correspond to a theoretical value.

The compensator 150 may obtain the second angle of the gravity direction g measured by the tilt sensor. The second angle may correspond to a measurement value of the tilt sensor.

The compensator 150 may compensate for the deviation between the first angle and the second angle. The compensator 150 may adjust the rotation angle of the support with respect to the ground so that the second angle follows the first angle.

Figure 5 is a flowchart showing the compensation method of the present invention.

The compensation method of FIG. 5 may be performed by the compensation device 100 shown in FIG. 1.

The compensation method may include a measurement step (S 510), a calculation step (S 520), and a compensation step (S 530).

In the measurement step (S510), measured values of the tilt sensor installed on the robot arm 10 may be obtained. The measuring step (S510) may be performed by the measuring unit 110.

In the calculation step (S520), the amount of deflection of the robot arm 10 can be estimated using the measured value of the tilt sensor installed on the robot arm 10. The calculation step (S520) may be performed by the calculation unit 130.

The compensation step (S 530) may compensate for the amount of deflection estimated in the calculation step (S 520). The compensation step (S530) may be performed by the compensation unit 150.

6 is a diagram illustrating a computing device according to an embodiment of the present invention. Computing device TN100 of FIG. 6 may be a device described herein (e.g., compensation device 100, etc.).

In the embodiment of FIG. 6, the computing device TN100 may include at least one processor TN110, a transceiver device TN120, and a memory TN130. Additionally, the computing device TN100 may further include a storage device TN140, an input interface device TN150, an output interface device TN160, etc. Components included in the computing device TN100 are connected by a bus TN170 and may communicate with each other.

The processor TN110 may execute a program command stored in at least one of the memory TN130 and the storage device TN140. The processor TN110 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Processor TN110 may be configured to implement procedures, functions, and methods described in connection with embodiments of the present invention. The processor TN110 may control each component of the computing device TN100.

Each of the memory TN130 and the storage device TN140 can store various information related to the operation of the processor TN110. Each of the memory TN130 and the storage device TN140 may be comprised of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory TN130 may be comprised of at least one of read only memory (ROM) and random access memory (RAM).

The transceiving device TN120 can transmit or receive wired signals or wireless signals. The transmitting and receiving device (TN120) can be connected to a network and perform communication.

Meanwhile, the embodiments of the present invention are not only implemented through the apparatus and/or method described so far, but may also be implemented through a program that realizes the function corresponding to the configuration of the embodiment of the present invention or a recording medium on which the program is recorded. This implementation can be easily implemented by anyone skilled in the art from the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the following claims are also possible. It falls within the scope of invention rights.

10...robot arm 90...control unit
100...compensation device 110...measuring unit
130...calculation department 150...compensation department

Claims (11)

A measuring unit that acquires measured values from a tilt sensor installed on the robot arm;
a calculation unit that estimates the amount of deflection of the robot arm using the measured value;
a compensation unit that compensates for the amount of deflection;
Compensating device comprising:
According to paragraph 1,
The measurement unit obtains at least one of a first measurement value, a second measurement value, and a third measurement value,
The first measurement value is a value measuring the inclination of a link corresponding to a joint of the robot arm and a node between the joints,
The second measurement value is a measurement of the tilt of the joint,
The third measurement value is a value measuring the inclination of the work tool provided at the end of the robot arm,
The calculation unit estimates the amount of deflection of the link using the first measurement value, estimates the amount of deflection of the joint using the second measurement value, or estimates the amount of deflection of the work tool using the third measurement value. compensation device.
According to paragraph 2,
The calculation unit calculates at least one of a first theoretical value, a second theoretical value, and a third theoretical value using the control value of the robot,
The first theoretical value includes a slope value of the link calculated using the control value,
The second theoretical value includes a tilt value of the joint calculated using the control value,
The third theoretical value includes a tilt value of the work tool calculated using the control value,
The calculation unit estimates the difference between the first measurement value and the first theoretical value as the amount of deflection of the link, estimates the difference between the second measurement value and the second theoretical value as the amount of deflection of the joint, or estimates the difference between the first measurement value and the second theoretical value as the amount of deflection of the joint. A compensation device that estimates the difference between the measured value and the third theoretical value as the amount of deflection of the work tool.
According to paragraph 1,
The measuring unit obtains the measured value of a tilt sensor installed at the work tool side end of the second link forming the robot arm or installed at the third joint at the work tool side end of the second link,
The compensation unit controls a module that moves the second link around a joint that is spaced apart from the second link and located upstream of the second link in order to compensate for an error of the measured value with respect to the theoretical value.
According to paragraph 1,
The measuring unit obtains the measured value of a tilt sensor installed at the work tool side end of the second link forming the robot arm or installed at the third joint at the work tool side end of the second link,
In order to compensate for the error of the measured value with respect to the theoretical value, the compensator is disposed at an end immediately in front of the second link and uses a first joint at the end of the robot body side of the first link to be rotatably connected to the second link. Controlling a module that moves the first link to the center,
A compensation device in which an error in a measured value of the second link or the third joint with respect to a theoretical value is compensated for by the movement of the first link.
According to paragraph 1,
The measuring unit obtains a tilt measurement value of a second link rotatably connected to the work tool side end of the first link forming the robot arm,
The compensator maintains the rotation angle of the second link with respect to the first link in its current state,
The compensator measures the tilt with respect to the second link while rotating the first link around a joint located upstream of the first link while maintaining the rotation angle of the second link with respect to the first link. A compensation device for matching a value to a theoretical value for the second link.
According to paragraph 1,
When a plurality of links are connected in a joint structure to form the robot arm,
Initially, the measuring unit acquires the slope of the upstream link closest to the body of the robot among the plurality of links,
The compensation unit compensates for the amount of deflection of the upstream link,
After the amount of deflection of the upstream link is compensated, the measuring unit acquires the inclination of the downstream link whose inclination has changed due to compensation of the amount of deflection of the upstream link,
The compensation unit is a compensation device that compensates for the amount of deflection of the downstream link when the amount of deflection of the upstream link is compensated and the slope of the downstream link is obtained.
According to paragraph 1,
The compensation unit is a compensation device that feedback controls the amount of deflection of the robot arm using the measured value.
A tilt sensor installed on a support supporting the target;
It includes a compensator that compensates for the amount of deflection of the target using the measured value of the tilt sensor installed on the support,
The compensation unit is a compensation device that corrects the inclination of the support in a direction in which the measured inclination value of the support follows a previously calculated theoretical value.
According to clause 9,
The compensator acquires only the first angle in the direction of gravity among the rotation angles of the posture calculated by forward kinematics,
The compensator acquires a second angle of the direction of gravity measured by the tilt sensor,
The compensation unit compensates for a deviation between the first angle and the second angle.
In a compensation method performed by a compensation device,
A measurement step of acquiring measured values from a tilt sensor installed on the robot arm;
A calculation step of estimating a deflection amount of the robot arm using the measured value;
A compensation step of compensating for the amount of deflection;
Compensation method including.

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