KR101012739B1 - Intelligent robot hand of humanoid robot and method for picking unknown object using the same - Google Patents

Abstract

The present invention gripping portion for holding an unknown object; A sensing unit for sensing the weight of the unknown object when lifting the unknown object through the holding unit; And a controller configured to control the gripping part to grip the unknown object with a gripping force corresponding to the weight corresponding to the unknown object according to the weight of the unknown object acquired by the sensing unit.

The present invention sets the force to intelligently grip the unknown object by measuring the weight of the unknown object in the process of gripping the unknown object through the three-axis force sensor installed on each finger, according to the user using an intelligent hand There is an advantage that it is possible to safely grasp the unknown object without damaging the weight data of various unknown objects to be grasped in advance to prevent damage.

Robot, robot, arm, arm, hand, hand, weight, sensor, 3-axis force sensor

Description

Intelligent hand and humanoid robot and method for picking unknown object using the same}

The present invention relates to an intelligent hand of a humanoid robot and a method of holding an unknown object using the same, and in particular, an intelligent hand of a humanoid robot capable of safely holding an unknown object without damage even when the holding condition data of an object to be gripped is not input and the same. It relates to an unknown object holding method used.

In general, the human hand robot should safely grasp the unknown object and perform the following work. However, the current human hand robot cannot hold a designated object having a predetermined stiffness or higher without being able to safely grasp an object that is low in stiffness, such as an egg or a paper cup, and easily breaks.

That is, the hand of the conventional humanoid robot gripping the object through the data related to the gripping force on the previously input object because it is very difficult to measure the force and the weight of the object at the same time. This makes it possible for current robot hands to

It was difficult to safely hold all kinds of unknown objects such as brittle glassware and eggs, or paper cups which easily deform under small pressure.

The present invention has been made to solve the above-mentioned problems, the intelligent hand of the humanoid robot that can automatically measure the weight of the unknown object and securely grip without breaking or dropping the unknown object with a predetermined gripping force according to the measured value and The purpose is to provide an unknown object holding method using the same.

In order to achieve the above object, a gripping portion for gripping an unknown object; A sensing unit for sensing the weight of the unknown object when lifting the unknown object through the holding unit; And a controller configured to control the gripping part to grip the unknown object with a gripping force corresponding to the weight corresponding to the unknown object according to the weight of the unknown object acquired by the detection unit. Provide intelligent hands. The gripping portion is composed of a plurality of fingers, the sensing unit is preferably mounted on each of the plurality of fingers.

The control unit compares the gripping pressure sensed by the sensing unit when the unknown object is lifted a predetermined height through the gripping unit, and compares the gripping pressure with a preset reference setting value, which is less than the reference setting value. After determining that the missed and set the reference set value large, the holding unit may be controlled to hold the unknown object.

The present invention also provides an intelligent hand of a humanoid robot installed on one side of an arm having a joint, the body being operatively coupled to the wrist of the arm and having a plurality of reducer integrated motors inside; And first to third fingers having one end connected to the main body and driven by the plurality of reduction gear integrated motors, wherein the first fingers are opposite to the second and third fingers so as to grip an object. The first to third fingers are disposed, the object can be achieved by providing an intelligent hand of the humanoid robot, characterized in that for sensing the weight of the object in the process of lifting the object.

Each of the first to third fingers may be provided with a three-axis force sensor in which an Fx force sensor, a Fy force sensor, and an Fz force sensor are integrally formed to detect forces in the X, Y, and Z axis directions.

Each of the first to third fingers may include a first node including the triaxial force sensor; And a second node having one end bent to the first node and the other end connected to the main body, the second node including a motor and a speed reducer for driving the first node.

The three-axis force sensor provides a rectangular deformation space in each of the three places, the rectangular deformation space formed in two of the rectangular deformation space serves as a horizontal axis, the rectangular deformation space formed in the other one serves as a vertical axis, the three-axis force sensor is a Wheat In order to form a stone bridge circuit, it is preferable that a total of 12 strain gauges are provided in each of the three rectangular deformation spaces.

In addition, the present invention, (a) holding a unknown object; (b) sensing the weight of the unknown object while lifting the held unknown object; And (c) setting a gripping force for gripping the unknown object according to the sensed weight. The above-described object may be achieved by providing a method for gripping an unknown object using an intelligent hand of a humanoid robot. .

In the step (a), when the unknown object is not gripped, the gripping pressure of the unknown object may be appropriately set by gripping the unknown object with a force greater than the initial gripping value for gripping the unknown object.

In another aspect, the present invention, (a) holding an unknown object with an intelligent hand having a plurality of fingers; (b) lifting the held unknown object; (c) a three-axis force sensor which is installed on each of the plurality of fingers during step (b) and integrally formed with an Fx force sensor, a Fy force sensor, and an Fz force sensor for detecting forces in the X, Y, and Z axis directions; Sensing the weight of the unknown object through; And (d) holding the unknown object with a force corresponding to the reference set value when the detected weight is smaller than a preset reference set value, and if the detected weight is larger than a preset reference set value, the unknown detected in step (c). By holding the unknown object with a force corresponding to the weight of the object; by providing an unknown object holding method using an intelligent hand of a humanoid robot, the above object can be achieved.

Step (a) may include: recognizing an object by whether the unknown object has touched a plurality of fingers through output values output by the plurality of three-axis force sensors; If it is recognized that the unknown object is in contact with the plurality of fingers, raising the intelligent hand to a predetermined height based on a preset reference setting value; And determining that the unknown object is not held when the sum of the respective output values detected by the plurality of three-axis force sensors is less than or equal to the reference set value, and doubles the holding force by twice the reference set value. It is preferable to include; setting.

In the present invention as described above, by setting the force to grip the unknown object by measuring the weight of the unknown object in the process of gripping the unknown object through the three-axis force sensor installed on each finger, according to the user Using intelligent hands, there is an advantage that it is possible to safely grasp the unknown object without damaging the weight data of various unspecified unknown objects to be grasped with an appropriate force.

Hereinafter, with reference to the accompanying drawings will be described the configuration of the intelligent hand of a humanoid robot according to an embodiment of the present invention.

Referring to FIG. 1, an intelligent hand 10 of a humanoid robot is a gripping portion for gripping an unknown object O, and includes first to third fingers 100, 200, and 300 and a main body 400. In addition, the intelligent hand 10 is connected to the second arm 30 via a wrist 31. The second arm 30 is interconnected via the first arm 20 and the elbow 21.

2 and 3, the first to third fingers 100, 200, and 300 serve as the thumb, the index finger, and the middle finger, respectively, and each finger 100, 200, or 300 detects a gripping pressure for holding an unknown object O. FIG. And the three-axis force sensor (110a, 210a, 310a) that serves as a sensing unit for sensing the weight of the unknown object (O) is mounted.

First, the configuration of the first finger 100 serving as the thumb will be described. The first finger 100 is composed of first and second nodes 110 and 140 having a predetermined length. The first node 110 is a three-axis force sensor integrally formed with three force sensors (Fx force sensor, Fy force sensor, Fz force sensor) to be described later for detecting the strength of the force in the X, Y, Z axis direction ( 110a).

The three-axis force sensor 110a provides square deformation spaces 111a, 111b, and 111c in three places, respectively, and the rectangular deformation spaces 111a and 111b formed in two of the rectangular deformation spaces serve as horizontal axes (see FIG. 4A). ), The rectangular deformation space 111c formed at the other one serves as a vertical axis. In this case, the three-axis force sensor 110a, together with the two three-axis force sensors 210a and 310a installed on the second and third fingers 200 and 300, respectively, measure the weight of the unknown object and measure the weight. By holding the force in the direction of holding as a reference, you can safely grasp the unknown object.

Such a three-axis force sensor (110a) is to configure a wheatstone bridge circuit for measuring the precision resistance when simultaneously measuring the force in one direction at Fx, Fy, Fz, as shown in Figures 4a and 4b A total of 12 strain gauges S1 to S12 are provided in three rectangular deformation spaces 111a, 111b, and 111c, respectively. The other two three-axis force sensors 210a and 310a likewise have a total of 12 strain gauges, four per three rectangular deformation spaces. Here, strain gauges S1 to S12 measure the resistance change by minimizing a slight error change. That is, the resistance of the metal can be expressed as R = ρ * L / S (where ρ: resistance constant, L: length, S: cross-sectional area), and if the strain gauges (S1 to S12) are subjected to tension or contraction force, Since the line width changes occur at the same time and the resistance changes, the Wheatstone bridge circuit can be used to determine the resistance change.

In addition, the three-axis force sensor (110a) is fixed to the front cover (110b) that one side is in direct contact with the unknown object with a bolt 113, the other side is fixed through the fixing pin (140g) on one side of the second node (140) It is rotatably connected about the pin 140g. Accordingly, the first node 110 is connected to the second node 140 so that the first node 110 can be pivoted by 90 ° or more in the gripping direction of the unknown object and 90 ° or more in the reverse gripping direction.

Moreover, the first node 110 includes five protective covers 110b to 110f surrounding the three-axis force sensor 110a. The five protective covers 110b to 110f have upper and lower surfaces of the front cover 110b which is in direct contact with the unknown object, the rear cover 110c installed on the opposite side of the front cover 110b, and the front / rear covers 110b and 110c. It consists of a side cover (110f) surrounding one side of the upper and lower cover (110d, 110e) and the front and rear upper and lower covers (110b, 110c, 110d, 110e) respectively coupled to. At this time, the remaining covers 110c, 110d, 110e, and 110f except for the front cover 110b maintain a non-contact state with the three-axis force sensor 110a.

The second node 140 includes a body 140a, an upper cover 140b and a lower cover 140c surrounding the body 140a. The motor 140d and the reducer 140e are fixedly installed on the body 140a, and the driving force generated from the motor 140d is transmitted to the fixing pin 140g through the plurality of spur gears 141a, 141b, 141c, and 141d. do. Both sides of the fixing pin 140g are rotatably supported by the bearing 140h, and are fixed to the other side of the triaxial force sensor 110a by fixing bolts 140i. Accordingly, the driving force of the motor 140d is transmitted to the spur gear 140d fixed to one end of the fixing pin 140g via the spur gears 141a, 141b, and 141c and finally through the reduction gear 140e. 1 node 110 is turned in the gripping direction or the reverse gripping direction together in the turning direction of the fixing pin (140g).

Referring to FIGS. 2 and 5, the second finger 200 performs an inspection area and includes first and second nodes 210 and 240 having a predetermined length.

The first node 210 is provided with the above-described three-axis force sensor 210a and its configuration is the same as the three-axis force sensor 110a installed in the first finger 100, and thus description thereof will be omitted. In addition, the first node 210 includes five protective covers 210b to 210f surrounding the three-axis force sensor 210a similarly to the first node 110 of the first finger 100 described above. The rear, top, bottom, and side covers 210c, 210d, 210e, and 210f except for the front cover 210b maintain a non-contact state with the three-axis force sensor 210a.

The second node 240 has the same configuration as the second node 140 of the first finger 100. That is, the second node 240 includes a body 240a, an upper cover 240b and a lower cover 240c surrounding the body 240a. The motor 240d and the reducer 240e are fixedly installed on the body 240a, and the driving force generated from the motor 240d is transmitted to the fixing pin 240g through the plurality of spur gears 241a, 241b, 241c, and 241d. do. Both sides of the fixing pin 240g are rotatably supported by the bearing 240h, and are fixed to the other side of the three-axis force sensor 210a by fixing bolts 240i. Accordingly, the driving force of the motor 240d is transmitted to the spur gear 240d fixed to one end of the fixing pin 240g through the reduction gear 240e through the spur gears 241a, 241b, and 241c. 1 section 210 pivots in the gripping direction or the reverse gripping direction together in the pivoting direction of the fixing pin (240g).

The third finger 300 serves as a middle finger, and is installed on the opposite side of the first finger 100 together with the above-described second finger 200 to hold the unknown object. The third finger 300 has first and second nodes 310 and 340, and the configuration thereof is the same as that of the second finger 200.

That is, the first node 310 is provided with the above-described three-axis force sensor 310a and its configuration is the same as the three-axis force sensors 110a and 210a installed on the first and second fingers 100 and 200, respectively. Omit. Like the first node 210 of the second finger 300 described above, the first node 310 includes five protective covers 310b to 310f surrounding the three-axis force sensor 310a. The rear, top, bottom, and side covers 310c, 310d, 310e, and 310f except for the front cover 310b maintain a non-contact state with the three-axis force sensor 310a.

The second node 340 has the same configuration as the second node 340 of the second finger 200. That is, the second node 340 includes a body 340a, an upper cover 340b and a lower cover 340c surrounding the body 340a. The motor 340d and the reduction gear 340e are fixedly installed on the body 340a, and the driving force generated from the motor 340d is transmitted to the fixing pin 340g through the plurality of spur gears 341a, 341b, 341c, and 341d. do. Both sides of the fixing pin 340g are rotatably supported by the bearing 340h, and are fixed to the other side of the three-axis force sensor 310a by fixing bolts 340i. Accordingly, the driving force of the motor 340d is transmitted to the spur gear 340d fixed to one end of the fixing pin 340g through the reduction gear 340e through the spur gears 341a, 341b, and 341c. The first node 310 pivots in the gripping direction or the reverse gripping direction together in the pivoting direction of the fixing pin 340g.

2, 3 and 5, the main body 400 includes a side plate 400a and an upper plate 400b and a lower plate 400c, one end of which is respectively fixed to upper and lower ends of the side plate 400a. The side plates 400a are provided with the first to third reduction gear integrated motors 410, 420, 430, respectively, and each motor 410, 420, 430 is used as a power source for driving the second nodes 140, 240, 340 of the first to third fingers 100, 200, 300. do.

The first motor 410 transmits a driving force to the fixing pin 415 through a pair of spur gears 411 and 413. The fixing pin 415 is fixed to the other side of the second node 140 of the first finger 100 through a plurality of fixing bolts 418, respectively, to the support protrusions 419a and 419b protruding from the main body 400. It is rotatably installed in the bearing 417 provided.

The second motor 420 transmits a driving force to the fixing pin 425 through a pair of spur gears 421 and 423. The fixing pin 425 is fixed to the other side of the second node 240 of the second finger 200 through a plurality of fixing bolts 428, respectively, to the support protrusions 429a and 429b protruding from the main body 400. It is rotatably installed in the bearing 427 provided.

The third motor 430 transmits power to the fixing pin 435 through the belt 432 connected to the pair of pulleys 431 and 433 respectively installed on the third motor 430 and the fixing pin 435. The fixing pin 435 is fixed to the other side of the second node 340 of the third finger 300 by a plurality of fixing bolts 438 and to the support protrusions 439a and 439b protruding from the main body 400. It is rotatably installed in the bearing 427 provided respectively.

A process of gripping an unknown object through the intelligent hand 10 of the humanoid robot according to the exemplary embodiment of the present invention configured as described above will be described with reference to FIG. 7.

First, when the power switch 40 is turned on to drive the intelligent hand 10 of the humanoid robot, the controller 50 sets the initial reference set value (200 g in this embodiment) and the comparative set value (this example). In the embodiment, 50g) is set (S1). Subsequently, the controller 50 sequentially measures the output values of the three triaxial force sensors 110a, 1210a, and 310a and outputs them to the display unit 60 (S2). 100, 200, 300 is set to the initial position (S3).

Next, the controller 50 drives the plurality of motors 140d, 240d, 340d, 410, 420, and 430 to drive the first to third fingers 100, 200, and 300 toward the unknown object O to be gripped (S4). At this time, the object is recognized based on whether the unknown object O has contacted the first to third fingers 100, 200, and 300 through the output values output by the three-axis force sensors 110a, 210a, and 310a (S5).

If it is recognized that the unknown object O is in contact with the first to third fingers 100, 200, and 300, the controller 50 is installed on the wrist 31 based on a reference set value (200 g in this embodiment). A predetermined motor (not shown) is driven to lift the main body 400 by about 10 mm in an upward direction (S6).

In this case, in order to check whether the unknown object O is safely held by the first to third fingers 100, 200, and 300, the controller 50 compares the output values of the three triaxial force sensors 110a, 210a, and 310a. Check whether it is less than or equal to the set value (set to 50g in this embodiment) (S7), and if less than or equal to 50g, determine that the unknown object O is missed and set the gripping force to twice the initial reference set value (S7). . The processes S1 to S7 are repeatedly performed until the unknown object O is safely gripped by the first to third fingers 100, 200 and 300.

When the unknown object O is securely gripped by the first to third fingers 100, 200, and 300 through at least one time through the processes S1 to S7, the controller 50 controls the three triaxial force sensors 110a, 210a, and 310a. Measure the weight of the unknown object (O) through (S9). The measuring method is the first object through the three three-axis force sensor (110a, 210a, 310a) by holding and lifting the unknown object (O) with a force of the reference set value 200g with the first to third fingers (100, 200, 300). The weight of O) is measured, and the formula for measuring is shown in Equation 1 below.

(here,

F: weight of unknown object, m: mass of unknown object, g: acceleration of gravity,

Fx1: force in the x direction measured by the finger triaxial force sensor 110a,

Fx2: force in the x direction measured by the finger 3-axis force sensor 210a,

Fx3: force in the x direction measured by the finger triaxial force sensor 310a,

Fy1: force in the y direction measured by the finger 3-axis force sensor 110a,

Fy2: force in the y direction measured by the finger 3-axis force sensor 210a,

Fy3: force in the y direction measured by the finger 3-axis force sensor 310a,

Fz1: Force in z direction measured by finger 3-axis force sensor 110a,

Fz2: Force in z direction measured by finger 3-axis force sensor 210a,

Fz3: Force in z direction measured by finger 3-axis force sensor 310a)

If the calculated value is smaller than the initial reference set value 200g, the controller 50 grips the unknown object O with the force of the initial reference set value through the first to third fingers 100, 200 and 300 (S10). If the value is 200g or more, the reference set value is changed and set to the weight of the unknown object O, and the unknown object O is gripped with a force corresponding to the changed reference set value (S11).

Finally, when the command switch 70 for placing the unknown object O is pressed, the controller 50 controls the intelligent hand 10 to safely seat the unknown object O held on the ground.

The intelligent hand 10 of the humanoid robot according to an embodiment of the present invention as described above sets a reference value and a comparative setting at least once without having to input a weight for an object each time it catches an unknown object having a different type and weight. By inputting a value, the rigidity of the unknown object can be grasped, and the unknown object can be grasped and lifted, and at the same time, the weight of the unknown object can be grasped so that the unknown object is not damaged.

In the above, the present invention has been illustrated and described with reference to specific preferred embodiments, but the present invention is not limited to the above-described embodiments, and the present invention is not limited to the spirit of the present invention. Various changes and modifications will be possible by those who have the same.

1 is a perspective view showing an intelligent hand of a humanoid robot according to an embodiment of the present invention;

2 is a plan view showing an intelligent hand of a humanoid robot according to an embodiment of the present invention;

3 is a plan view showing a main body and a first finger of an intelligent hand of a humanoid robot according to an embodiment of the present invention;

4A and 4B are a side view and a plan view illustrating a three-axis force sensor included in the first to third fingers;

5 is a plan view illustrating a main body and second and third fingers of an intelligent hand of a humanoid robot according to an embodiment of the present invention;

6 is a schematic diagram showing a state in which an unknown object is held by an intelligent hand of a humanoid robot according to an embodiment of the present invention;

7 is a control block diagram of an intelligent hand of a humanoid robot according to an embodiment of the present invention;

8 is a flowchart illustrating a process of gripping an unknown object through an intelligent hand of a humanoid robot according to an exemplary embodiment of the present invention.

* Explanation of Signs of Major Parts in Drawings *

100: first finger 110a, 210a, 310a: three-axis force sensor

200: second finger 300: third finger

400: main body

Claims (11)

A gripping portion for gripping an unknown object; A sensing unit for sensing the weight of the unknown object when lifting the unknown object through the holding unit; And And a controller configured to control the gripping unit to grip the unknown object with a gripping force corresponding to the weight corresponding to the unknown object according to the weight of the unknown object acquired by the detection unit. hand. The method of claim 1, The gripping portion is composed of a plurality of fingers, The sensing unit is an intelligent hand of a humanoid robot, characterized in that each mounted on the plurality of fingers. The comparison setting of claim 1, wherein the control unit compares the gripping pressure sensed by the sensing unit when the unknown object is lifted a predetermined height through the gripping unit, compared to a preset reference setting value, and is set smaller than the reference setting value. If the value is less than the value, the intelligent object of the humanoid robot, characterized in that it is determined that the unknown object is missed, and the reference set value is set to a large value, and then the holding unit is controlled to hold the unknown object. In the intelligent hand of a humanoid robot installed on one side of an arm having a joint, A main body operatively coupled to the wrist of the arm and having a plurality of reduction gear integrated motors inside; And First to third fingers connected to the main body and driven by the plurality of reduction gear integrated motors, respectively; The first finger is disposed opposite the second and third fingers so that the object can be gripped, and the first to third fingers detect the weight of the object in the process of lifting the object. Intelligent hand of the robot. According to claim 4, wherein the first to third fingers are each provided with a three-axis force sensor formed integrally with the Fx force sensor, Fy force sensor and Fz force sensor for detecting the force in the X, Y and Z-axis direction Featuring intelligent hands of humanoid robots. The method of claim 5, wherein the first to third fingers, respectively, A first node including the triaxial force sensor; And An intelligent hand of a humanoid robot comprising: a second node having one end bent to the first node and the other end connected to the main body, the second node including a motor and a reducer for driving the first node. . The method of claim 6, wherein the three-axis force sensor has a rectangular deformation space in each of the three places, the rectangular deformation space formed in two of the rectangular deformation space serves as a horizontal axis, the rectangular deformation space formed in the other one serves as a vertical axis, The three-axis force sensor is an intelligent hand of a humanoid robot, characterized in that a total of 12 strain gauges are installed in each of the three rectangular deformation space to form a Wheatstone bridge circuit. (a) holding an unknown object; (b) sensing the weight of the unknown object while lifting the held unknown object; And and (c) setting a gripping force for gripping the unknown object in accordance with the sensed weight. The method of claim 8, wherein step (a) When the unknown object is not held, the unknown object using the intelligent hand of the humanoid robot, characterized in that for holding the unknown object with a force greater than the initial gripping value for holding the unknown object. (a) gripping an unknown object with an intelligent hand having multiple fingers; (b) lifting the held unknown object; (c) a three-axis force sensor which is installed on each of the plurality of fingers during step (b) and integrally formed with an Fx force sensor, a Fy force sensor, and an Fz force sensor for detecting forces in the X, Y, and Z axis directions; Sensing the weight of the unknown object through; And (d) holding the unknown object with a force corresponding to the reference setting value when the detected weight is smaller than a preset reference setting value, and if the detected weight is larger than the preset reference setting value, the unknown object detected in step (c). And holding the unknown object with a force corresponding to the weight of the unknown object using the intelligent hand of a humanoid robot. The method of claim 10, wherein step (a) Recognizing an object by whether the unknown object has touched a plurality of fingers through an output value output by the plurality of three-axis force sensors; If it is recognized that the unknown object is in contact with the plurality of fingers, raising the intelligent hand to a predetermined height based on a preset reference setting value; And Determining that the unknown object is missed when the sum of the respective output values sensed by the plurality of three-axis force sensors is smaller than or equal to the reference set value, and setting the gripping force to twice the reference set value. The unknown object holding method using an intelligent hand of a humanoid robot comprising a.

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