KR101363209B1 - Apparatus and method for contolling articulated robot - Google Patents

Abstract

Disclosed are an apparatus and a method for controlling an articulate robot. The apparatus for controlling an articulated robot calculates distances between a plurality of links when working. The apparatus for controlling an articulated robot derives a minimum value from the calculated distances and optimizes the work if the derived minimum value is lower than a preset threshold value. [Reference numerals] (510) Distance calculation unit; (520) Minimum value calculation unit; (530) Operation optimization unit

Description

Control device and method of articulated robot {APPARATUS AND METHOD FOR CONTOLLING ARTICULATED ROBOT}

The following embodiments relate to an apparatus and a method for controlling an articulated robot, and in particular, during the operation of the articulated robot, it is determined whether links constituting the articulated robot collide with each other to operate the articulated robot. It relates to an apparatus and a method for optimizing.

An articulated robot is a robot that can freely move with links that can move at various angles. The articulated robot generally combines the links with three or more rotary motion mechanisms, and when the articulated robot moves, it can drive the rotary motion mechanism (generally a motor) to perform an operation.

The articulated robot may take various postures, and various control methods may be applied to how each link should be operated when the posture is changed from the first posture to the second posture.

In the case where a plurality of links must be moved to perform a specific operation, the respective links may collide with each other. Therefore, among the plurality of rotary motion mechanisms, the importance of a technique for determining which rotary motion mechanism is driven at what time and how much is increasing.

The following embodiments aim to optimize the operation of an articulated robot.

The following embodiments aim to prevent and determine whether the links of the articulated robot collide with each other while performing an operation.

According to an exemplary embodiment, in the control device of a articulated robot composed of a plurality of links, when the articulated robot drives the links to change the posture from a first posture to a second posture, Control of the articulated robot including a distance calculator for calculating the distance between each link, a minimum value calculator for calculating the minimum value of the calculated distance between each link, and an operation optimizer for optimizing the operation based on the calculated minimum value. An apparatus is disclosed.

Here, the minimum value calculator divides the time interval from the first time point when the articulated robot takes the first posture to the second time point when the articulated robot takes the second posture, into a plurality of sub-sections, respectively. The minimum value may be calculated for the sub period of, and the operation optimizer may optimize the operation for each sub period.

The minimum value calculator sets a third viewpoint between the first viewpoint in which the first posture is taken and the second viewpoint in which the second posture is taken, and relates to a fourth viewpoint between the first viewpoint and the third viewpoint. And the minimum value is a section between the first time point and the third time point or the fourth time point and the second time point according to a comparison result of the fourth distance at the fourth time point and the third distance at the third time point. It may be determined which section is located among the sections between viewpoints.

In addition, when the distance between the first time point and the third time point is greater than the distance between the third time point and the second time point, the fourth time point may be determined according to Equation 1 below.

[Equation 1]

는 상기 제4 시점이고,

는 상기 제3 시점이고,

는 상기 제1 시점이다.here,

Is the fourth time point,

Is the third time point,

Is the first time point.

Here, the minimum value calculator sets a candidate minimum value for the distance, and wherein the calculated distance coincides with the candidate minimum value between the first time point taking the first posture and the second time point taking the second posture. It may be determined whether a time point exists, and the minimum value may be calculated according to the determination.

The minimum value calculator may determine whether the third time point exists based on a speed at which the first link included in the plurality of links moves in the direction of the second link included in the plurality of links.

The operation optimizer may optimize the operation when the calculated minimum value is smaller than a predetermined threshold value.

According to another exemplary embodiment, in a method of controlling a jointed-arm robot composed of a plurality of links, the articulated robot drives the links to change an attitude from a first posture to a second posture. The control method of the articulated robot includes a step of calculating a distance between each link, calculating a minimum value of the calculated distance between each link, and optimizing the operation based on the calculated minimum value. do.

The method may further include: dividing the time interval from the first time point in which the articulated robot takes the first posture to the second time point in which the articulated robot takes the second posture into a plurality of sub-sections. The calculating of the minimum value may include calculating a minimum value for each of the sub-sections, and the optimizing the operation may optimize the operation with respect to each of the sub-sections.

And setting a third view point between the first view point taking the first posture and the second view point taking the second posture and a fourth view point between the first view point and the third view point. According to a result of the comparison of the fourth distance at and the third distance at the third time point, the minimum value is selected from the interval between the first time point and the third time point or the interval between the fourth time point and the second time point. The method may further include determining which section it is located in.

The setting of the fourth view may be performed when the distance between the first view and the third view is greater than the distance between the third view and the second view. It can be determined according to Equation 2.

&Quot; (2) "

는 상기 제4 시점이고,

는 상기 제3 시점이고,

는 상기 제1 시점이다.here,

Is the fourth time point,

Is the third time point,

Is the first time point.

Here, the step of setting a candidate minimum value for the distance, there is a third time point that the calculated distance coincides with the candidate minimum value between the first time point taking the first pose and the second time point taking the second pose. The method may further include determining whether to determine whether to calculate the minimum value, and calculating the minimum value according to the determination.

The determining of whether the third viewpoint exists may include determining whether the third viewpoint is based on a speed at which a first link included in the plurality of links moves in a direction of a second link included in the plurality of links. It can be determined whether it exists.

Further, the optimizing the operation may optimize the operation when the calculated minimum value is smaller than a predetermined threshold value.

According to the following embodiments, it is possible to prevent a collision between links during the operation of the articulated robot.

FIG. 1 is a diagram illustrating a concept in which an articulated robot including a plurality of links performs an operation of changing a state.
Fig. 2 is a block diagram showing the structure of a control device for an articulated robot according to an exemplary embodiment.
3 is a diagram illustrating a concept of controlling an operation of an articulated robot based on a minimum value calculated according to an exemplary embodiment.
4 is a diagram illustrating a distance between a plurality of links constituting the articulated robot.
Fig. 5 is a block diagram showing the structure of a control device for an articulated robot according to still another exemplary embodiment.
FIG. 6 is a diagram illustrating a minimum value search method according to a golden section search method.
FIG. 7 illustrates a method for searching for a minimum value according to a conservative enhancement (CA) technique.
Fig. 8 is a flowchart illustrating a step-by-step method for controlling an articulated robot according to still another exemplary embodiment.
9 is a flowchart illustrating a step-by-step method for searching for a minimum value according to a golden section search method.
FIG. 10 is a flowchart illustrating a method of searching for a minimum value according to a Conservative Advancement (CA) method.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

FIG. 1 is a diagram illustrating a concept in which an articulated robot including a plurality of links performs an operation of changing a state.

In (a) of FIG. 1, the articulated robot takes a first state with both arms lowered. The articulated robot may take an operation of changing from the first state to a second state in which the arms shown in FIG. 1B overlap the chest.

In the case of performing the operation described in FIG. 1, the articulated robot collects both arms into the chest. In this case, if the articulated robot starts to move both arms at the same time and moves at the same speed, both arms of the articulated robot may collide with each other. Therefore, both arms of the articulated robot cannot overlap.

In order to solve the problem described in FIG. 1, before the articulated robot performs a specific operation, a technique for determining whether or not links constituting the articulated robot collide with each other is required.

Fig. 2 is a block diagram showing the structure of a control device for an articulated robot according to an exemplary embodiment. The control device 200 of the articulated robot includes an operation optimizer 210, an operation parameter extractor 220, a distance calculator 230, and a minimum value calculator 240.

The motion optimizer 210 optimizes the motion of each link when the articulated robot performs a specific motion by moving the link. The motion optimizer 210 may control an operation of a motor driving a joint connecting each link for this purpose. For example, the operation optimizer 210 may determine how much time each motor should be rotated.

The operation parameter extractor 220 extracts a parameter for an operation determined by the operation optimizer 210. The parameter extracted by the operation parameter extractor 220 may be information about a rotation speed, a position, and a direction of each link according to time of each motor.

The distance calculator 230 calculates a distance between each link while the articulated robot performs an operation. The distance calculator 230 may calculate a distance between each link by using parameters for an operation determined by the operation optimizer 210. The distance between each link will be described in detail with reference to FIG. 4.

The minimum value calculator 240 calculates a minimum value among distances between links that change with time. If the calculated minimum is less than '0', the two links collide while performing the operation. In this case, the motion optimizer 210 may optimize the motion of the articulated robot again to prevent collision between links.

3 is a diagram illustrating a concept of controlling an operation of an articulated robot based on a minimum value calculated according to an exemplary embodiment.

부터

까지의 시간 구간을 복수의 서브 구간(310, 320, 330, 340, 350, 360)으로 분할하고, 분할된 서브 구간(310, 320, 330, 340, 350, 360) 각각에 대하여 최소값을 산출할 수 있다.3 is a view showing that the distance between two links of the articulated robot changes as the articulated robot performs an operation. The distance between the links of the articulated robots is represented by solid lines. The control device of the articulated robot performs the motion of the articulated robot.

from

A time interval up to is divided into a plurality of sub-sections 310, 320, 330, 340, 350, and 360, and a minimum value is calculated for each of the divided sub-sections 310, 320, 330, 340, 350, and 360. Can be.

The control device of the articulated robot compares the minimum value of each sub-section (310, 320, 330, 340, 350, 360) with a predetermined threshold value. Here, the threshold is a value set by the control device of the articulated robot in order to effectively control the articulated robot. According to one embodiment, the threshold may be determined as '0'. In this case, if the distance between the links is less than '0', since the links collide with each other, the articulated robot control apparatus may optimize the operation of the sub-section having a minimum value smaller than the threshold.

Referring to FIG. 3, the distance between the links may have a minimum value in the sub period 320, and the minimum value may be smaller than '0'. In this case, the links of the articulated robot may collide with each other. Therefore, the control device of the articulated robot may optimize the operation of the sub section 320 and the other sub sections 330 and 340 adjacent to the sub section 320.

In Fig. 3, the distance between the links after the optimization is represented by a dotted line. Referring to FIG. 3, the minimum value in the sub period 320 is greater than or equal to '0'. Thus, collisions between links are prevented.

In FIG. 3, only an embodiment in which the threshold is '0' is illustrated, but the control device of the articulated robot may set the threshold to a value greater than '0'. In this case, each link of the articulated robot is moved at a distance greater than the threshold.

4 is a diagram illustrating a distance between a plurality of links constituting the articulated robot.

In order to simply calculate the distance between the links, the links 410 and 420 constituting the articulated robot are combined with the hemispheres 411 and 413 on the top and bottom surfaces of the cylinder 412, respectively, as shown in FIG. It can be modeled in the form.

In FIG. 4, center lines 414 and 421 may be set at the center of each link 410 and 420. Each center line is a line connecting the top center and the bottom center of the cylinder 412.

이고, 제2 링크(420)에서, 원통의 반지름 및 반원의 반지름이

인 경우에, 중심선간의 거리(430)가

+

라면, 각 링크간의 거리(440)는 '0'일 수 있다. 여기서, 중심선(414, 421)간의 거리는 중심선(414, 421)간의 유클리디안 거리(Euclidian distance)로 정의될 수 있다.According to one side, the control device of the articulated robot can simply calculate the distance 440 between the links using only the distance 430 between the center lines 414, 421 of each link 420. For example, in the first link 410, the radius of the cylinder 412 and the radius of the semicircles 410, 411 are

In the second link 420, the radius of the cylinder and the radius of the semicircle are

If the distance between centerlines 430 is

+

If so, the distance 440 between each link may be '0'. Here, the distance between the center lines 414 and 421 may be defined as an Euclidian distance between the center lines 414 and 421.

According to an exemplary embodiment, the distance calculator 230 may simply calculate the distance between each link shown in FIG. 3 using an operating parameter and a model of the link shown in FIG. 4.

Fig. 5 is a block diagram showing the structure of a control device for an articulated robot according to still another exemplary embodiment. The control device 500 of the articulated robot includes a distance calculator 510, a minimum value calculator 520, and an operation optimizer 530.

When the articulated robot performs the operation of changing the posture from the first posture to the second posture, the distance calculator 510 calculates the distance between each link constituting the articulated robot. According to one side, the distance calculator 510 may calculate the distance between each link by using the extracted operating parameters and the link model shown in FIG. 4. Here, the extracted operation parameter may be information about a rotational speed according to time of the motors moving each link, the position and the direction of each link at the time of starting the operation.

The minimum value calculator 520 calculates the minimum value of the distance between each link when the articulated robot performs an operation. According to one side, the minimum value calculating unit 520 may calculate the minimum value of the distance between links using various methods such as Golden Section Search, Conservative Advancement (CA) search, and hybrid search method. Can be. According to one side, the minimum value calculator 520 divides the time interval from the first time point in which the articulated robot takes a first posture to the second time point in which the articulated robot takes a second posture into a plurality of sub-sections, respectively. The minimum value may be calculated for the sub interval of.

The motion optimizer 530 may optimize the motion of the articulated robot based on the calculated minimum value. When the minimum value calculator 520 divides the time interval from the first time point to the second time point into a plurality of sub-sections, the operation optimizer 530 may optimize the operation for each sub-section.

According to one side, the operation optimizer 530 may compare the calculated minimum value with a predetermined threshold value. When the calculated minimum value is smaller than the predetermined threshold value, the operation optimizer 530 may optimize the operation of the sub-section and the sub-sections adjacent to the sub-section. According to one side, the predetermined threshold may be '0'.

Hereinafter, a searcher method in which the minimum value calculator 520 calculates the minimum value of the distance between links will be described.

1) Golden Section Search

FIG. 6 is a diagram illustrating a minimum value search method according to a golden section search method. 6 is the time axis, and the vertical axis is the distance between links.

First, the minimum value calculator 520 selects the third time point 630 between the first time point 610 and the second time point 620 in the time interval between the first time point 610 and the second time point 620. Set it. The minimum value calculator 520 may generate a first view point 610 and a third point according to the distance between the first view point 610 and the third view point 630 and the distance between the third view point 630 and the second view point 620. It may be located between the viewpoints 630 and may be located between the third viewpoint 630 and the second viewpoint 620.

According to one side, when the distance between the first time point 610 and the third time point 630 is shorter than the distance between the third time point 630 and the second time point 620, the fourth time point 640 is the first time. It is located between the third time point 630 and the second time point 620. In contrast, when the distance between the first view point 610 and the third view point 630 is longer than the distance between the third view point 630 and the second view point 620, the fourth view point 640 is the first view point. 610 and the third time point 630 are located there.

According to one side, when the fourth time point 640 is located between the first time point 610 and the third time point 630, the minimum value calculator 520 is the first time point 610 and the third time point 630. ), The fourth time point may be determined. The minimum value calculator 520 may determine the fourth time point 640 according to Equation 1 below.

[Equation 1]

는 제4 시점이고,

는 제3시점이고,

는 제1 시점이다
here,

Is the fourth time point,

Is the third time point,

Is the first time point

According to one side, when the fourth time point 640 is located between the third time point 630 and the second time point 620, the minimum value calculator 520 is the third time point 630 and the second time point 620. ), The fourth time point may be determined. The minimum value calculator 520 may determine the fourth time point 640 according to Equation 2 below.

&Quot; (2) "

는 제4 시점이고,

는 제3시점이고,

는 제2 시점이다.
here,

Is the fourth time point,

Is the third time point,

Is the second time point.

When the fourth view point 640 is located between the first view point 610 and the third view point 630, the minimum value calculator 520 may set the fourth distance 641 and the fourth distance 641 at the fourth view point 640. The third distance 631 at the three viewpoints 630 is compared. If the fourth distance 641 at the fourth time point 640 is greater than the third distance 631 at the third time point 630, the minimum value calculator 520 is the first time point 610. The minimum value between the second view 620 and the second view point 620 may be determined to be located in a section between the second view point 620 and the fourth view point 640. In this case, the minimum value calculator 520 may further narrow the section in which the minimum value is determined by reapplying the search described with reference to FIG. 6 for the section between the fourth time point 640 and the second time point 620. have.

On the contrary, if the fourth distance 641 at the fourth time point 640 is smaller than the third distance 631 at the third time point 630, the minimum value calculator 520 is the first time point 610. The minimum value between the second view 620 and the second view point 620 may be determined to be located in a section between the first view point 610 and the third view point 630. In this case, the minimum value calculator 520 may apply the search described with reference to FIG. 6 again to the section between the first time point 610 and the third time point 630.

Even when the fourth view point 640 is located between the third view point 630 and the second view point 620, the minimum value calculator 520 has the fourth view point 640 as the first view point 610 and the third view point. The process in which it is determined that the minimum value is located may be further narrowed through a similar process as in the case of 630.

By repeating the search described in FIG. 6, the section in which the minimum value is located can be grasped with sufficient precision. According to one side, the minimum value calculator 520 may determine that the minimum value is located is narrow enough, or if the search is repeated more than a predetermined number of times, stop searching for the minimum value and determine the time when the minimum value is located. .

2) How to search for Conservative Advancement

FIG. 7 is a view illustrating a minimum value search method according to a CA (Conservative Advancement) search method. The horizontal axis in FIG. 7 is time, and the vertical axis is the distance between links.

The minimum value calculator 520 compares the first distance at the first time point at which the time interval starts and the second distance at the second time point at which the time interval ends. The minimum value calculator 520 may perform a CA search method based on a time point corresponding to a smaller distance among the first distance and the second distance. In FIG. 7, since the first distance 710 at the first time point 711 is smaller, the minimum value calculator 520 performs the CA search method based on the first time point 711.

라고 설정하고, 링크간의 거리의 하한선을

라고 설정한다. 일측에 따르면, 최소값 산출부(520)는 하기 수학식 2에 따라서 링크간의 거리의 하한선

를 설정할 수 있다.
The minimum value calculator 520 determines the first distance 710 at the first time point 711.

The lower limit of the distance between links

Is set. According to one side, the minimum value calculator 520 is the lower limit of the distance between the links according to the following equation (2)

Can be set.

&Quot; (2) "

은 제1 링크를 구성하는 원통의 반지름이고,

는 제2 링크를 구성하는 원통의 반지름이다. 도 4를 참고하면, 각 링크의 중심선(414, 421)이 서로 접하는 경우에 링크간의 거리는

이 된다.here,

Is the radius of the cylinder constituting the first link,

Is the radius of the cylinder constituting the second link. Referring to FIG. 4, when the centerlines 414 and 421 of each link are in contact with each other, the distance between the links is

.

(720)과 하한선

(720)사이에 중간 거리

(730)를 설정한다. 일측에 따르면, 최소값 산출부(520)는 중간 거리

(730)를 제1 거리

(720)과 하한선

(720)의 산술 평균값으로 설정할 수 있다.The minimum value calculator 520 may have a first distance at the first time point.

720 and the lower limit

Intermediate distance between 720

730 is set. According to one side, the minimum value calculator 520 is an intermediate distance

730 first street

720 and the lower limit

The arithmetic mean of 720 can be set.

(730)만큼 이격되는 시간을 산출한다. 일측에 따르면, 중간 거리

(730)를 후보 최소값이라 할 수 있다.The minimum value calculator 520 may determine the position, distance, and moving speed of the first link 410 and the second link 420 at the first time point 711, from the first link 410 to the second link 420. The distance between the first link 410 and the second link 420 in consideration of the direction of the

The time spaced by 730 is calculated. According to one side, the middle distance

730 may be referred to as a candidate minimum value.

(730)만큼 이격되는 제3 시점이 존재하는지 여부를 판단할 수 있다. 최소값 산출부(520)는 제1 링크(410)의 이동 속도 중에서, 제1 링크(410)로부터 제2 링크(420)까지의 방향에 해당하는 이동 속도만을 추출할 수 있다. 예를 들어, 최소값 산출부(520)는 제1 링크(410)의 이동 속도를 제1 링크(410)로부터 제2 링크(420)까지의 방향에 프로젝션(projection)시켜 제1 링크(410)가 제2 링크(420)로 이동하는 최대 속도만을 추출할 수 있다. 최소값 산출부(520)는 추출된 속도를 이용하여 제1 링크(410)와 제2 링크(420)가 중간 거리

(730)만큼 이격되는 시간을 산출할 수 있다.In this case, the minimum value calculator 520 may determine the distance between the two links 410 and 420 based on the speed at which the first link 410 moves in the direction of the second link 420.

It may be determined whether there is a third time point spaced apart by 730. The minimum value calculator 520 may extract only a moving speed corresponding to a direction from the first link 410 to the second link 420 among the moving speeds of the first link 410. For example, the minimum value calculator 520 may project the movement speed of the first link 410 in a direction from the first link 410 to the second link 420 so that the first link 410 is projected. Only the maximum speed of moving to the second link 420 may be extracted. The minimum value calculator 520 uses the extracted speed to determine the intermediate distance between the first link 410 and the second link 420.

A time spaced by 730 may be calculated.

(730) 보다 작다면, 제1 링크(410)와 제2 링크(420)간의 거리가 중간 거리(후보 최소값)

(730)과 일치하는 시점이 존재한다. 이를 간단히 제3 시점(731)이라고 하자. 이 경우에, 링크간의 거리의 최소값은 제3 시점(731)과 제2 시점간의 시간 구간에 위치한다.If the minimum distance between links is the intermediate distance (candidate minimum value)

If less than 730, the distance between the first link 410 and the second link 420 is an intermediate distance (candidate minimum value).

There is a time point that coincides with 730. Let this simply be the third time point 731. In this case, the minimum value of the distance between the links is located in the time interval between the third time point 731 and the second time point.

를 설정할 수 있다. 일측에 따르면, 최소값 산출부(520)는

(730)와

(720)간의 사이에서 새로운 중간 거리(후보 최소값)

(740)를 설정할 수 있다.Referring to FIG. 7, the minimum value calculator 520 may generate a new intermediate distance (candidate minimum value).

Can be set. According to one side, the minimum value calculator 520 is

730 and

New intermediate distance between candidates (candidate minimum)

740 may be set.

(740) 보다 크다면, 최소값 산출부(520)는 제1 링크(410)와 제2 링크(420)가

(740)만큼 이격되는 시간을 산출할 수 없다. 또는, 산출된 시간이 제2 시점(

)보다 더 큰 의미없는 값이 산출된다. 따라서, 이 경우에, 최소값 산출부(520)는 링크간 거리의 최소값이

(740) 보다는 크고,

(730)보다는 작은 값인 것으로 판단할 수 있다.If the minimum distance between links is the intermediate distance (candidate minimum value)

If greater than 740, the minimum value calculator 520 determines that the first link 410 and the second link 420 are connected to each other.

It is not possible to calculate the time spaced apart by 740. Alternatively, the calculated time is the second time point (

Yields a more significant value than Therefore, in this case, the minimum value calculator 520 determines that the minimum value of the distance between links is small.

Greater than 740,

It may be determined that the value is smaller than 730.

By repeating the search described with reference to FIG. 7, the minimum value calculator 520 may grasp the section in which the minimum value 750 is located with sufficient precision. According to one side, the minimum value calculation unit 520 stops searching for the minimum value and determines the time point 751 where the minimum value is located when it is determined that the section in which the minimum value is located is sufficiently narrowed or the search is repeated more than a predetermined number of times. You can decide.

3) Hybrid Search

Hybrid search is a combination of golden partition search and CA search.

According to the hybrid search method, the minimum value calculator 520 may narrow the section where the minimum value is determined by using the CA search method. In this case, the minimum value calculator 520 may reduce the search time by approaching the minimum value in both directions of the start point of the time section and the end point of the time section.

If it is determined that the section in which the minimum value is located is sufficiently narrowed, the minimum value calculator 520 may search for the correct minimum value using the golden division search method.

Fig. 8 is a flowchart illustrating a step-by-step method for controlling an articulated robot according to still another exemplary embodiment.

In step 810, the control device of the articulated robot calculates the distance between each link when the articulated robot drives the links to change the pose from the first posture to the second posture. According to one side, the control device of the articulated robot can calculate the distance between each link using the extracted operating parameters and the link model shown in FIG. Here, the extracted operation parameter may be information about a rotational speed according to time of the motors moving each link, the position and the direction of each link at the time of starting the operation.

In operation 820, the control device of the articulated robot may divide the time interval from the first time point that the articulated robot takes the first posture to the second time point that takes the second posture into a plurality of sub-sections.

In step 830, the control device of the articulated robot calculates the minimum value of the distance between the links. According to one side, the control device of the articulated robot can calculate the minimum value by selecting any one of 1) golden division search method 2) CA search method 3) hybrid search method.

1) golden division exploration

9 is a flowchart illustrating a step-by-step method for searching for a minimum value according to a golden section search method. Hereinafter, the golden division searching method will be described step by step with reference to FIG. 9.

In step 910, the control device of the articulated robot sets a third time point and a fourth time point. According to one side, the control device of the articulated robot sets a third viewpoint between the first viewpoint and the second viewpoint in the time interval between the first viewpoint and the second viewpoint. In addition, the control device of the articulated robot sets a fourth viewpoint between the first viewpoint and the third viewpoint. According to one side, the control device of the articulated robot may determine a fourth time point according to the first time point and the third time point. The control device of the articulated robot may determine a fourth time point according to Equation 1 above.

In step 920, the control device of the articulated robot according to the comparison result of the fourth distance at the fourth time point and the third distance at the third time point, the minimum value is the interval between the first time point and the third time point or the third time point. It is determined which section of the section between the 4th view point and the 2nd view point.

In step 930, the control device of the articulated robot determines whether to end the golden segment search method. According to one side, the control device of the articulated robot determines that the section determined to be the minimum value is found correctly if the section determined to be the minimum value is less than a predetermined range, and can terminate the golden segment search method. have.

Alternatively, the control device of the articulated robot may determine whether to terminate the golden segment search method according to whether the search is performed more than a predetermined number of times.

2) CA search method

FIG. 10 is a flowchart illustrating a method of searching for a minimum value according to a search method of CA.

In step 1010, the control device of the articulated robot sets a candidate minimum value for the distance between links.

와 일치하는 제3 시점이 존재하는지 여부를 판단한다.In step 1020, the control device of the articulated robot determines that the distance between links is a candidate minimum value between a first time point at which the articulated robot takes a first pose and a second time point at which a second pose is taken.

It is determined whether there is a third time point coinciding with.

만큼 이격되는 시간을 산출할 수 있다.The control device of the articulated robot may extract only the maximum moving speed corresponding to the direction from the first link to the second link among the moving speeds of the first link. For example, the control device of the articulated robot may project only the maximum speed at which the first link moves to the second link by projecting the moving speed of the first link in the direction from the first link to the second link. have. The control device of the articulated robot uses the extracted velocity to determine the candidate minimum value of the first link and the second link.

It can calculate the time spaced apart.

If there is a third time point, the control device of the articulated robot may set a new candidate minimum value and search for a more accurate minimum value in step 1010.

In step 830, the control device of the articulated robot calculates the minimum value of the distance between each link.

In operation 840, the control device of the articulated robot may optimize the operation of the articulated robot based on the calculated minimum value. According to one side, the control device of the articulated robot can compare the calculated minimum value with a predetermined threshold value. When the calculated minimum value of the articulated robot is smaller than a predetermined threshold value, the control device of the articulated robot may optimize operations of the corresponding sub-section and the sub-sections adjacent to the sub-section.

The method according to an embodiment may be implemented in the form of a program command that can be executed through various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions to be recorded on the medium may be those specially designed and configured for the embodiments or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the embodiments, and vice versa.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. For example, it is to be understood that the techniques described may be performed in a different order than the described methods, and / or that components of the described systems, structures, devices, circuits, Lt; / RTI > or equivalents, even if it is replaced or replaced.

Therefore, other implementations, other embodiments, and equivalents to the claims are also within the scope of the following claims.

500: control device of articulated robot
510: distance calculation unit
520: minimum value calculation unit
530: motion optimization unit

Claims (15)

In the control device of an articulated robot composed of a plurality of links,
A distance calculator configured to calculate a distance between the links when the articulated robot drives the links to change a posture from a first posture to a second posture;
A minimum value calculator for calculating a minimum value of the calculated distances between the links; And
An operation optimizer configured to optimize the operation based on the calculated minimum value
Lt; / RTI >
And the motion optimizer optimizes the motion when the calculated minimum value is smaller than a predetermined threshold value. The method of claim 1,
The minimum value calculating unit divides the time interval from the first time point at which the articulated robot takes the first posture to the second time point at which the articulated robot takes the second posture, into a plurality of sub-sections, and each sub Calculate the minimum value for the interval,
And the motion optimizer optimizes the motion for each of the sub-sections. The method of claim 1,
The minimum value calculator sets a third viewpoint between a first viewpoint taking the first posture and a second viewpoint taking the second posture,
According to a result of a comparison between the fourth distance at the fourth time point and the third distance at the third time point, the minimum value is determined from the fourth time point between the first time point and the third time point. The control device of the articulated robot, which determines whether it is located in the section between the third view point or the section between the fourth view point and the second view point. The method of claim 3,
The fourth time point
Equation

Lt; / RTI >

Is the fourth time point,

Is the third time point,

Is a control device of the articulated robot which is the first time point. The method of claim 1,
The minimum value calculator sets a candidate minimum value for the distance, and a third time point at which the calculated distance coincides with the candidate minimum value between the first time point taking the first posture and the second time point taking the second posture. The control apparatus of the articulated robot which judges whether there exists and calculates the minimum value according to the determination. 6. The method of claim 5,
The minimum value calculator may be configured to determine whether the third viewpoint exists based on the maximum speed at which the first link included in the plurality of links moves in the direction of the second link included in the plurality of links. controller. delete In the control method of the articulated robot composed of a plurality of links,
Calculating a distance between the links when the articulated robot drives the links to change a posture from a first posture to a second posture;
Calculating a minimum value of the calculated distances between the links; And
Optimizing the operation based on the calculated minimum value
Lt; / RTI >
The optimizing of the motion may include optimizing the motion when the calculated minimum value is smaller than a predetermined threshold value. 9. The method of claim 8,
Dividing the time interval from the first time point in which the articulated robot takes the first posture to the second time point in which the articulated robot takes the second posture into a plurality of sub-sections;
Further comprising:
The calculating of the minimum value may include calculating a minimum value for each sub-section,
The optimizing of the motion may include controlling the motion of the articulated robot for each of the sub-sections. The method of claim 8, wherein calculating the minimum value
Setting a third view point between the first view point taking the first position and the second view point taking the second position and a fourth view point between the first view point and the third view point;
According to a comparison result of a fourth distance at the fourth time point and a third distance at the third time point, the minimum value is a section between the first time point and the third time point or the fourth time point and the second time point. Determining which section of the interval between
Control method of the articulated robot further comprising. The method of claim 10, wherein in the setting of the fourth viewpoint,
The fourth time point
Equation

Lt; / RTI >

Is the fourth time point,

Is the third time point,

Is a control method of the articulated robot. 9. The method of claim 8,
Setting a candidate minimum for the distance;
Determining whether there is a third time point in which the calculated distance coincides with the candidate minimum value between the first time point of the first pose and the second time point of the second pose.
Further comprising:
The calculating of the minimum value may include calculating the minimum value according to the determination. The method of claim 12,
The determining of whether the third viewpoint exists includes the third viewpoint based on a maximum speed at which a first link included in the plurality of links moves in a direction of a second link included in the plurality of links. Control method of the articulated robot. delete A computer-readable recording medium having recorded thereon a program for executing the method of any one of claims 8 to 13.

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