Foot for walking robot

Abstract

The present invention provides a foot for a walking robot, the foot including: a main body part which is hinge-fastened to legs of a walking robot and thus connected thereto, and has multiple mounting slots formed thereon; a sensor part which is mounted in the mounting slots of the main body part and measures a force applied to the main body part in contact with the ground when the walking robot walks; and a calculation part which is connected to the sensor part and, on the basis of the force measured by the sensor part, calculates the center of gravity of the main body part when the walking robot walks.

Description

The feet of a walking robot

[0001] The present invention relates to a foot of a walking robot, and more particularly, to a foot of a walking robot that measures a force applied to a main body part that contacts the ground when the walking robot walks and calculates the center of gravity of the main body part when the walking robot walks.

[0002] Referring to the background technology described in Korean Patent No. 10-2503700, walking robots can be classified into two-legged walking robots that imitate the walking form of humans, four-legged walking robots that imitate the body structure and walking form of mammals, and multi-legged walking robots with four or more legs. For two-legged walking robots, it is especially important to maintain balance while walking to ensure stable walking.

[0003] The ZMP (Zero Moment Point) method is a representative method for stably controlling a walking robot and measuring the center of gravity of the walking robot. It is a method for controlling and measuring the center of gravity of the walking robot so that the center of gravity point is continuously located inside the foot of the walking robot during walking by measuring the force (hereinafter, landing force) generated when the foot of the walking robot lands on the ground.

[0004] Traditionally, landing force was measured by mounting Force / Torque (F / T) sensors on the ankles of walking robots. However, F / T sensors are very expensive, and using high-performance F / T sensors capable of more accurate landing force measurement requires a significant budget.

[0005] The present invention was created to solve the above problems, and the purpose is to provide a foot of a walking robot that does not use an expensive F / T sensor, but instead mounts an FSR (Force Sensitive Resistor) sensor, which is cheaper than an F / T sensor, in a plurality of mounting slots formed in the main body of a walking robot, and measures the force applied to the sensors mounted in the plurality of mounting slots when the walking robot walks, thereby calculating the center of gravity of the main body when the walking robot walks.

[0006] In order to achieve the above object, the present invention provides a leg of a walking robot, including a main body part that is hinge-connected to a leg of a walking robot and has a plurality of mounting slots formed therein; a sensor part that is mounted in the mounting slot of the main body part and measures a force applied to the main body part that is in contact with the ground when the walking robot walks; and a calculation part that is connected to the sensor part and calculates the center of gravity of the main body part when the walking robot walks based on the force measured by the sensor part.

[0007] In the foot of the walking robot according to the present invention, the main body may include a first grounding body that is rotatably coupled to the leg of the walking robot and is grounded on the ground when the walking robot walks, a second grounding body that is rotatably coupled to the leg of the walking robot and is spaced apart from the first grounding body, and a connecting body that connects the first grounding body and the second grounding body, and the first grounding body and the second grounding body may be plates having a shape of an equilateral triangle.

[0008] The first grounding body and the second grounding body may each include a grounding surface that is grounded to the ground, and a first inclined surface and a second inclined surface that are roundly bent upward and connected at both ends of the grounding surface, and the mounting slot may be formed inside the first grounding body and the second grounding body on the first inclined surface and the second inclined surface.

[0009] The first grounding body and the second grounding body may be formed with a first coupling hole and a second coupling hole, respectively, to which the legs of the walking robot are rotatably coupled, and the first coupling hole and the second coupling hole may be formed to penetrate the first grounding body and the second grounding body adjacent to a portion where the first inclined surface and the second inclined surface are connected in a rounded manner.

[0010] The above mounting slot may be formed to penetrate the first grounding body and the second grounding body, and a first connecting hole and a second connecting hole connected to the mounting slot may be formed on both sides of the first grounding body and the second grounding body to penetrate the first grounding body and the second grounding body, respectively.

[0011] The above mounting slot can be formed in the first grounding body and the second grounding body through one method selected from wire cutting and electrical discharge machining.

[0012] The sensor unit mounted in the above mounting slot may include a first sensor mounted in a mounting slot formed on a first inclined surface of the first grounding body, a second sensor mounted in a mounting slot formed on a second inclined surface of the first grounding body, a third sensor mounted in a mounting slot formed on the first inclined surface of the second grounding body, and a fourth sensor mounted in a mounting slot formed on the second inclined surface of the second grounding body, and the first sensor, the second sensor, the third sensor, and the fourth sensor may be FSR (Force Sensitive Resistor) sensors.

[0013] The above calculation unit can calculate the center of gravity of the main body when the walking robot walks using the following [Mathematical Formula 1].

[0014] [Mathematical Formula 1]

[0015]

[0016]

[0017] Here, is the center of gravity in the X direction of the main body, is the center of gravity in the Y direction of the main body, is the force measured by the first sensor, is the force measured by the second sensor, is the force measured by the third sensor, is the force measured by the fourth sensor, Inland is the distance in the X direction from the center of the main body to the first to fourth sensors, Inland Indicates the Y-direction distance from the center of the main body to the first to fourth sensors.

[0018] According to the foot of the walking robot according to the present invention, the force applied to the main body of the walking robot when walking can be measured using an FSR (Force Sensitive Resistor) sensor that is less expensive than an F / T sensor, thereby reducing the manufacturing cost of equipment for measuring the center of gravity of the walking robot, and by preventing the FSR sensor from contacting the ground, the durability of the sensor can be improved, and the center of gravity of the main body of the walking robot can be easily measured when walking by having a calculation unit calculate an average of the forces measured by a plurality of sensors mounted on the main body.

[0019] FIG. 1 is a schematic drawing of the feet of a walking robot according to an embodiment of the present invention.

[0020] Figure 2 is a front view of the main body shown in Figure 1.

[0021] Figure 3 is a plan view of the main body shown in Figure 2.

[0022] FIG. 4 is a schematic diagram illustrating a principle of measuring the center of gravity of a walking robot using the feet of the walking robot according to an embodiment of the present invention.

[0023] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be construed as limited to their conventional or dictionary meanings. Based on the principle that the inventor can appropriately define the concepts of terms to best explain his or her invention, they should be interpreted in a way that conforms to the technical spirit of the present invention.

[0024] Referring to FIG. 1, the foot (100) of the walking robot according to an embodiment of the present invention includes a main body (1100), a sensor part (1200), and an operation part (1300), and the main body (1100) is hinge-connected to the leg (L) of the walking robot.

[0025] A hinge hole (h) that is hinge-connected to the main body (1100) by a hinge pin (P) is formed in the leg (L) of the above-mentioned walking robot, and the main body (1100) to which the leg (L) of the above-mentioned walking robot is hinge-connected includes a first grounding body (1110), a second grounding body (1120), and a connecting body (1130).

[0026] Referring to FIGS. 1 to 3, the first grounding body (1110) is rotatably coupled to the leg (L) of the walking robot by the hinge pin (P), the first grounding body (1110) is grounded to the ground when the walking robot walks, and a mounting slot (1112a, 1113a) in which a sensor unit (1200) to be described later is mounted is formed in the first grounding body (1110).

[0027] The second grounding body (1120) is also rotatably connected to the leg (L) of the walking robot by the hinge pin (P), and the second grounding body (1120) is positioned apart from the first grounding body (1110).

[0028] When the above-mentioned walking robot walks, the second grounding body (1120) is also grounded to the ground, and a mounting slot (1122a, 1123a) in which a sensor unit (1200) described later is mounted is formed in the second grounding body (1120).

[0029] The first grounding body (1110) and the second grounding body (1120), which are spaced apart from each other so as to correspond to the center of the leg (L) of the walking robot, are connected by a connecting body (1130), and the first grounding body (1110) and the second grounding body (1120) connected by the connecting body (1130) are preferably made of a plate having a shape of an equilateral triangle, and the connecting body (1130) is preferably made of a plate having a shape of a square.

[0030] Referring to FIGS. 1 and 3, the first grounding body (1110) includes a grounding surface (1111), a first inclined surface (1112), and a second inclined surface (1113). The grounding surface (1111) is in contact with the ground when the walking robot walks, and the first inclined surface (1112) and the second inclined surface (1113) are roundly bent upward at both ends of the grounding surface (1111) and are connected in a rounded manner.

[0031] The first grounding body (1110) is formed with the first connecting hole (1110a) to which the leg (L) of the walking robot is rotatably connected, and the first connecting hole (1110a) is formed to penetrate the first grounding body (1110) adjacent to the portion where the first inclined surface (1112) and the second inclined surface (1113) are connected in a round manner.

[0032] It is preferable that the first connecting hole (1110a) be located above the portion where the connecting body (1130) connecting the first grounding body (1110) and the second grounding body (1120) is connected to the first grounding body (1110).

[0033] Mounting slots (1112a, 1113a) are formed on the first inclined surface (1112) and the second inclined surface (1113) to which a sensor unit (1200) described later is mounted. The mounting slots (1112a, 1113a) are formed inside the first grounding body (1110), and the mounting slots (1112a, 1113a) may be formed to have a shape that is folded in multiple stages inside the first grounding body (1110).

[0034] The above mounting slots (1112a, 1113a) are formed to penetrate the first grounding body (1110) in the width direction, and on both sides of the first grounding body (1110), first connecting holes (1110b) connected to the mounting slots (1112a, 1113a) are formed to penetrate the first grounding body (1110) in the width direction.

[0035] Since the first connecting hole (1110b) is connected to the mounting slot (1112a, 1113a), the range in which the mounting slot (1112a, 1113a) opens is variable when the walking robot walks, and it is preferable that the mounting slot (1112a, 1113a) is formed in the first grounding body (1110) through one method selected from wire cutting or electrical discharge machining.

[0036] The above second grounding body (1120) also includes a grounding surface (1121), a first inclined surface (1122), and a second inclined surface (1123). The second grounding body (1120) is the same in shape and configuration as the first grounding body (1110) except for the position at which it is connected to the leg (L) of the walking robot, and a detailed description thereof will be omitted.

[0037] Referring to FIGS. 1 to 3, the leg (L) of the walking robot is hinge-connected to the first ground body (1110) and the second ground body (1120) by the hinge pin (P), so that the first ground body (1110) and the second ground body (1120), which are connected by the connecting body (1130), rotate around the hinge hole (h) of the leg (L) of the walking robot.

[0038] The sensor unit (1200) mounted on the mounting slot (1112a, 1113a) formed on the first grounding body (1110) of the main body (1100) and the mounting slot (1122a, 1123a) formed on the second grounding body (1120) serves to measure the force applied to the main body (1100) that is grounded on the ground when the walking robot walks.

[0039] The above sensor unit (1200) includes a first sensor (1210), a second sensor (1220), a third sensor (1230), and a fourth sensor (1240). The first sensor (1210) is mounted in a mounting slot (1112a) formed in a first inclined surface (1112) of the first grounding body (1110), and the second sensor (1220) is mounted in a mounting slot (1113a) formed in a second inclined surface (1113) of the first grounding body (1110).

[0040] The third sensor (1230) is mounted in a mounting slot (1122a) formed in a first inclined surface (1122) of the second grounding body (1120), and the fourth sensor (1240) is mounted in a mounting slot (1123a) formed in a second inclined surface (1123) of the second grounding body (1120). It is preferable that an FSR (Force Sensitive Resistor) sensor be used as the first sensor (1210), the second sensor (1220), the third sensor (1230), and the fourth sensor (1240).

[0041] When the robot foot moves while supporting the ground, the width of the mounting slot decreases, and a load is applied to the sensor unit (1200) mounted in the mounting slot.

[0042] The FSR sensor used as the above sensor unit (1200) includes a resistance member configured to have a constant resistance formed on an insulating base fabric having flexibility, an electrode member formed on an insulating upper fabric so as to face and be spaced apart from the resistance member by a predetermined interval, and a spacer attached to a border portion, which is an edge of the insulating base fabric and the insulating upper fabric, with a predetermined width so as to space the resistance member and the electrode member apart from each other. Since the FSR sensor is a general one, a detailed description of the process of measuring force by the FSR sensor will be omitted.

[0043] The sensor unit (1200) is connected to the calculation unit (1300), and the calculation unit (1300) calculates the center of gravity of the main body unit (1100) when the walking robot walks based on the force measured by the sensor unit (1200).

[0044] Referring to FIGS. 1 and 4, it is preferable that the calculation unit (1300) calculates the center of gravity of the main body (1100) based on the force measured by the first sensor (1210), the second sensor (1220), the third sensor (1230), and the fourth sensor (1240) of the sensor unit (1200) when the walking robot walks, using the following [Mathematical Formula 1].

[0045] [Mathematical Formula 1]

[0046]

[0047]

[0048] Here, is the center of gravity in the X direction of the main body, is the center of gravity in the Y direction of the main body, is the force measured by the first sensor, is the force measured by the second sensor, is the force measured by the third sensor, is the force measured by the fourth sensor, Inland is the distance in the X direction from the center of the main body to the first to fourth sensors, Inland Indicates the Y-direction distance from the center of the main body to the first to fourth sensors.

[0049] The above calculation unit (1300) can easily calculate the X-direction center of gravity and the Y-direction center of gravity of the main body (1100) based on the force measured by the first sensor (1210), the second sensor (1220), the third sensor (1230), and the fourth sensor (1240) of the sensor unit (1200) and the distances from the center of the main body (1100) of the first sensor (1210), the second sensor (1220), the third sensor (1230), and the fourth sensor (1240).

[0050] Therefore, by using a low-cost FSR (Force Sensitive Resistor) sensor rather than an expensive F / T sensor, the force applied to the main body (1100) when the walking robot walks can be measured, thereby reducing the manufacturing cost of equipment for measuring the center of gravity of the walking robot, and by preventing the FSR sensor from contacting the ground, the durability of the sensor can be improved, and the center of gravity of the main body (1100) can be easily measured when the walking robot walks by calculating the average of the forces measured by a plurality of sensors mounted on the main body (1100) by the calculation unit (1300).

[0051] While the present invention has been described with reference to the embodiments illustrated in the drawings, these are merely exemplary, and those skilled in the art will appreciate that various modifications and equivalent alternative embodiments are possible. Therefore, the true scope of technical protection of the present invention should be determined by the technical spirit of the appended claims.

[0052] The present invention can be applied to a walking robot.

Claims

1. A main body part that is hinge-connected to the legs of a walking robot and has a plurality of mounting slots formed; A sensor part mounted in the mounting slot of the main body part and measuring the force applied to the main body part that is grounded when the walking robot walks; and A foot of a walking robot, which is connected to the sensor unit and includes a calculation unit that calculates the center of gravity of the main body when the walking robot walks based on the force measured by the sensor unit.

2. In claim 1, The above main body part, A first grounded body that is rotatably connected to the legs of the above-mentioned walking robot and is grounded on the ground when the above-mentioned walking robot walks; A second grounded body that is rotatably connected to the legs of the above walking robot and is positioned apart from the first grounded body, A foot of a walking robot including a connecting body connecting the first grounding body and the second grounding body.

3. In claim 2, A foot of a walking robot, characterized in that the first grounding body and the second grounding body are plates in the shape of an equilateral triangle.

4. In claim 3, The above first grounding body and the above second grounding body are respectively, A ground plane that is grounded to the ground, It includes a first inclined plane and a second inclined plane that are roundly bent upward and connected in a round manner at both ends of the above ground plane, A foot of a walking robot in which the mounting slot is formed inside the first grounding body and the second grounding body on the first inclined surface and the second inclined surface.

5. In claim 4, The first grounding body and the second grounding body are formed with a first joining hole and a second joining hole, respectively, to which the legs of the walking robot are rotatably joined. The above first joining hole and the above second joining hole are formed so as to penetrate the first grounding body and the second grounding body adjacent to the portion where the first inclined surface and the second inclined surface are roundly connected. The foot of the walking robot.

6. In claim 4, The above mounting slot is formed to penetrate the first grounding body and the second grounding body, A foot of a walking robot, in which a first connecting hole and a second connecting hole, each connected to the mounting slot, are formed on both sides of the first grounding body and the second grounding body so as to penetrate the first grounding body and the second grounding body.

7. In claim 6, A foot of a walking robot, characterized in that the mounting slot is formed in the first grounding body and the second grounding body by one method selected from wire cutting and electrical discharge machining.

8. In claim 4, The sensor part mounted in the above mounting slot is, A first sensor mounted in a mounting slot formed on the first inclined surface of the first grounding body, A second sensor mounted in a mounting slot formed on the second inclined surface of the first grounding body, A third sensor mounted in a mounting slot formed on the first inclined surface of the second grounding body, It includes a fourth sensor mounted in a mounting slot formed on the second inclined surface of the second grounding body, A foot of a walking robot, characterized in that the first sensor, the second sensor, the third sensor, and the fourth sensor are FSR (Force Sensitive Resistor) sensors.

9. In claim 1, The above operation unit, A foot of a walking robot, characterized in that the center of gravity of the main body is calculated using the following [Mathematical Formula 1] when the walking robot walks. [Mathematical formula 1] Here, is the center of gravity in the X direction of the main body, is the center of gravity in the Y direction of the main body, is the force measured by the first sensor, is the force measured by the second sensor, is the force measured by the third sensor, is the force measured by the fourth sensor, Inland is the distance in the X direction from the center of the main body to the first to fourth sensors, Inland represents the distance in the Y direction from the center of the main body to the first to fourth sensors.

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