Moving body and method for controlling moving body

Abstract

An apparatus may include a plurality of wheels, a body coupled to the plurality of wheels, and a controller configured to determine an angular velocity of the body relative to a ground surface, and control a rotational speed of the plurality of wheels based on the angular velocity. A method may include determining, by a controller, an angular velocity of a body coupled to a plurality of wheels; determining whether the angular velocity is not less than the reference angular velocity; and adjusting a rotational speed of the plurality of wheels based on a result of the determining step.

Description

Technical Field

[0001] The present invention relates to a moving body and a method for controlling the moving body. Background Art

[0002] A mobile body may refer to an object that can be moved using wheels or other means. Various forms of mobile bodies may be developed. Among them, in order to overcome the limitations of the wheel structure, a mobile body that can use flexible tires that can make the shape of the wheels deformable to go up and down obstacles such as stairs or steps may be considered.

[0003] In the process of the moving body going up and down obstacles such as stairs or steps, the moving body may encounter a section where the angle between the moving body and the ground changes rapidly due to the steps of the obstacle. If the moving speed of the moving body is constant when the moving body climbs up the obstacle, the front wheels of the moving body may collide with the next step, whereby the moving body may be strongly impacted.

[0004] Furthermore, in the process of the moving body overcoming the step of the obstacle, if the moving body travels while descending by moving backward, the rear wheels of the moving body may fall with a high acceleration, whereby the moving body may receive a strong impact.

[0005] Therefore, a technology for reducing the impact applied to a moving body by adjusting the moving speed of the moving body in the process of overcoming an obstacle is desired. Summary of the invention

[0006] According to the present invention, an apparatus may include: a plurality of wheels, a body coupled to the plurality of wheels, and a controller configured to determine an angular velocity of the body relative to the ground and control a rotational speed of the plurality of wheels based on the angular velocity.

[0007] In the device, a wheel among a plurality of wheels is configured to dynamically shape as it moves so that a first length of the wheel becomes smaller than a second length of the wheel, wherein the first length is a first distance between a first point of the wheel contacting the ground and a central axis of the wheel, and wherein the second length is a second distance between a second point of the wheel not contacting the ground and the central axis of the wheel.

[0008] In the apparatus, the plurality of wheels rotate so that the body moves forward, and wherein the controller is configured to reduce the rotation speed of the plurality of wheels based on an absolute value of the angular velocity of the body being greater than a first reference angular velocity.

[0009] In the device, multiple wheels rotate to move the body forward, and wherein, the controller is configured to increase the rotation speed of the multiple wheels until the rotation speed of the multiple wheels reaches a reference rotation speed after the rotation speed of the multiple wheels decreases, based on the absolute value of the angular velocity of the body being no greater than a first reference angular velocity.

[0010] In the device, a controller is configured to determine an angle of a body relative to the ground, wherein a plurality of wheels rotate to cause the body to move forward, and wherein the controller is configured to reduce a rotation speed of the plurality of wheels based on an absolute value of an angular velocity of the body being greater than a first reference angular velocity and an angle of the body relative to the ground being not less than a reference angle.

[0011] In the device, a wheel among a plurality of wheels is configured to be dynamically shaped as it moves so that a first length of the wheel becomes smaller than a second length of the wheel, wherein the first length is a first distance between a first point of the wheel contacting the ground and a central axis of the wheel, wherein the second length is a second distance between a second point of the wheel not contacting the ground and the central axis of the wheel, and wherein a controller is configured to determine a first reference angular velocity based on the first length and the second length.

[0012] In the apparatus, the plurality of wheels rotate so that the body moves backward, and wherein the controller is configured to reduce the rotation speed of the plurality of wheels based on an absolute value of the angular velocity of the body being greater than a second reference angular velocity.

[0013] In the device, the controller is configured to increase the rotation speed of the plurality of wheels until the rotation speed of the plurality of wheels reaches the reference rotation speed based on the absolute value of the angular velocity of the body being not greater than the second reference angular velocity after the rotation speed of the plurality of wheels is reduced.

[0014] The device may further include a receiving portion coupled to an upper side of the body, wherein the plurality of wheels include front wheels coupled to a front side of the body and rear wheels coupled to a rear side of the body, wherein a center of gravity of the body is formed on an upper side of the front wheels.

[0015] In the device, each of the multiple wheels includes: a circular frame, a circular first impact absorbing member connected to the outer side of the circular frame, an annular second impact absorbing member spaced apart from the circular first impact absorbing member in a radially outward direction, and a third impact absorbing member connecting a point of the circular first impact absorbing member and a point of the annular second impact absorbing member.

[0016] In the device, the third impact absorbing member is configured to elastically support the annular second impact absorbing member relative to the circular first impact absorbing member. In the device, the third impact absorbing member extends in an inclined manner in a radially outward direction between the circular first impact absorbing member and the annular second impact absorbing member. In the device, the third impact absorbing member extends in a curved shape.

[0017] According to the present invention, a method may include the following steps: determining, by a controller, the angular velocity of a body coupled to a plurality of wheels, determining whether the magnitude of the angular velocity is not less than the magnitude of a reference angular velocity, and adjusting the rotational speed of the plurality of wheels based on the result of the determination step. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects, features and advantages of the present invention will become more apparent through the following detailed description in conjunction with the accompanying drawings, in which:

[0019] Figure 1 An example of a moving body according to an embodiment of the present invention is shown;

[0020] Figure 2 An example of a state in which the first to third impact absorbing members land on the ground is shown;

[0021] Figure 3 An example is shown in which the length of the main body is such that the front wheels can be located on the upper side of the next staircase in a condition immediately before the rear wheels of the moving body climb up the stairs;

[0022] Figure 4 An example is shown in which the length of the main body is such that the front wheels can contact the next staircase in a condition just after the rear wheels of the moving body have climbed up the stairs;

[0023] Figure 5 An example of control of a moving object according to an embodiment of the present invention is shown;

[0024] Figure 6 An example showing a situation immediately before the rear wheels of a moving object climb up stairs;

[0025] Figure 7 An example showing a situation in which the rear wheels of a moving object have just climbed up stairs;

[0026] Figure 8 An example showing the conditions just before and just after the rear wheel climbs the stairs;

[0027] Fig. 9 , Fig.10 and Fig.11 An example of a state in which a moving body moves backward and climbs down stairs is shown in sequence; and

[0028] Fig.12 Another example of control of a moving object according to an embodiment of the present invention is shown.

[0029] Description of Reference Numerals

[0030] 10: Wheels

[0031] 10a: Front wheel

[0032] 10b: Rear wheel

[0033] 11: Framework

[0034] 12: First shock absorbing member

[0035] 13: Second shock absorbing member

[0036] 14: Third impact absorbing member

[0037] 20: Main body

[0038] 30: Controller

[0039] 40: Accommodation

[0040] L1: first length

[0041] L2: Second length. DETAILED DESCRIPTION

[0042] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that when adding reference numerals to components in the accompanying drawings, the same components are represented by the same reference numerals even when drawn in different drawings. In addition, when describing embodiments of the present invention, when it is determined that the detailed description of related well-known configurations and functions may hinder the understanding of the embodiments of the present invention, the detailed description thereof will be omitted.

[0043] Hereinafter, a moving body may refer to a structure such as a vehicle that can be moved by wheels 10 or other moving means. A moving body according to an embodiment of the present invention relates to a moving body that can go up and down obstacles such as stairs or steps. Hereinafter, it will be described assuming that the obstacle has a stair shape.

[0044] Figure 1 An example of a moving object according to an embodiment of the present invention is shown.

[0045] The mobile body according to the present invention may include a wheel 10, a main body 20, and a controller 30. The wheel 10 may be rotatably coupled to the main body 20. In addition, the wheel 10 may be configured to rotate in forward and reverse directions. As an example, the main body 20 is provided with a plurality of motor components, and the wheel 10 may be connected to the motor components. However, the present invention is not limited thereto, and the wheel 10 may rotate by connecting a pair of shafts of the wheel 10 as in a normal vehicle.

[0046] The mobile body according to an embodiment of the present invention may further include a housing portion 40. The housing portion 40 may be a component for storing items therein. The housing portion 40 may be coupled to the upper side of the main body 20. The housing portion 40 may be disposed biased toward the front side of the upper side of the main body 20. Since the mobile body further includes the housing portion 40, the center of gravity of the mobile body may be formed on the upper side of the front wheel 10a.

[0047] As an example, the wheel 10 may be a wheel 10 capable of moving over obstacles such as stairs and steps. The wheel 10 may include a front wheel 10a and a rear wheel 10b.

[0048] As an example, each wheel 10 may include a frame 11, a first shock absorbing member 12, a second shock absorbing member 13, and a third shock absorbing member 14. The frame 11 may have a circular shape.

[0049] The first shock absorbing member 12 may be a circular member connected to the outside of the frame 11. The second shock absorbing member 13 may be an annular member spaced radially outward from the first shock absorbing member 12. The center of the second shock absorbing member 13 may coincide with the center of the first shock absorbing member 12.

[0050] The third shock absorbing member 14 may be a member connecting one point of the first shock absorbing member 12 and one point of the second shock absorbing member 13. Thus, a line connecting the one point of the first shock absorbing member 12 and its central axis may not be parallel to a line connecting the one point of the first shock absorbing member 12 and the one point of the second shock absorbing member 13.

[0051] In general, the first shock absorbing member 12 and the third shock absorbing member 14 may be disposed inside the second shock absorbing member 13 .

[0052] The first, second and third impact absorbing members 12, 13 and 14 may be integrally formed. As an example, the first, second and third impact absorbing members 12, 13 and 14 may be formed of a rubber material, but the present invention is not limited thereto.

[0053] The third shock absorbing member 14 may elastically support the second shock absorbing member 13 with respect to the first shock absorbing member 12. Therefore, as described above, the first length L1 of the wheel 10 may be smaller than the second length L2 thereof.

[0054] The third shock absorbing member 14 may extend obliquely with respect to the radially outward direction between the first shock absorbing member 12 and the second shock absorbing member 13. The third shock absorbing member 14 may extend in a curved manner.

[0055] Figure 2 An example of a state in which the first to third impact absorbing members land on the ground is shown. For the purpose of explanation, a first length L1 and a second length L2 will be defined. The first length L1 may be a length obtained by connecting a contact portion of the wheel 10 and a central axis thereof when the wheel 10 contacts the ground. The second length L2 may be a length of a radius of the wheel 10 when the wheel 10 does not contact the ground.

[0056] like Figure 2 As shown, the first length L1 of the wheel 10 may be formed to be smaller than the second length L2. This may mean that if the wheel 10 is squeezed by the contact portion, the length obtained by connecting the contact portion and the center axis of the wheel 10 will be reduced.

[0057] The main body 20 may satisfy a specific length condition. As an example, in a condition just before the rear wheel 10b climbs up the stairs, the main body 20 should have a length greater than a length at which the front wheel 10a can be located on the upper side of the next stair. Also, as an example, in a condition after the rear wheel 10b has climbed up the stairs, the main body 20 should have a length less than a length at which the front wheel 10a can contact the next stair.

[0058] Figure 3 An example is shown in which the length of the main body is such that the front wheels can be positioned on the upper side of the next staircase in a state immediately before the rear wheels of the moving body climb up the stairs. Figure 4 An example is shown in which the length of the main body is such that the front wheels can contact the next step of stairs just after the rear wheels of the moving body have climbed up the stairs. Figure 1 ). In addition, for the convenience of illustration, Figure 3 and Figure 4 The wheel 10 is shown to be circular, but as described above, the wheel 10 may be a wheel 10 whose shape may be changed according to a contact portion.

[0059] As the length L of the main body 20 is comparable Figure 3 The case is longer and longer than Figure 4 This can be expressed by the following equation.

[0060] In the following equation, L means the longitudinal length of the body 20, H means the height of one staircase, and W means the width of one staircase. As an example, H may be 0.18 m, and W may be 0.28 m.

[0061] R may refer to the radius of the wheel 10, and this may correspond to the second length L2. As an example, R may be 0.15 m.

[0062] [Equation 1]

[0063] (W+R) 2 +(2H) 2 <L<(2W-R) 2 +H 2

[0064] The controller 30 is coupled to the body 20 and can control the movement of the wheel 10. The controller 30 can be configured to obtain the angular velocity of the body 20 relative to the ground. As an example, the controller 30 may include an angular velocity sensor that measures the angular velocity. The controller 30 can obtain the angular velocity measured by the angular velocity sensor. However, the controller 30 can also obtain the angular velocity through other auxiliary devices without using the angular velocity sensor. As an example, the controller 30 may include a device that continuously obtains the angle between the ground and the body 20.

[0065] The controller 30 may control the revolutions per minute (rpm) of the wheel 10 based on the angular velocity of the body 20 .

[0066] The controller 30 may include a processor and a memory. The processor may include a microprocessor such as a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or a central processing unit (CPU). The memory may store control instructions as a basis for instructions generated by the processor to control the rpm. The memory may be a data storage device such as a hard disk drive (HDD), a solid state drive (SSD), a volatile medium, or a non-volatile medium.

[0067] A method of using a laser sensor or an ultrasonic sensor to detect the step of an obstacle and the interval distance between the wheel and the obstacle in order to control the rpm of the wheel may be considered. In this method, a plurality of relatively expensive laser sensors or ultrasonic sensors must be installed, and the laser value measured is different depending on the shape of the obstacle, so it is difficult to apply to general purposes. In addition, it may become difficult to obtain the step and the interval distance depending on the road surface condition.

[0068] According to the present invention, since the rpm of the wheel 10 can be controlled based on the angular velocity of the body 20, the manufacturing cost can be reduced while the system is simplified, and the system can be applied regardless of the state of the road.

[0069] Hereinafter, the operation of the moving body climbing up the stairs according to the embodiment of the present invention will be described in detail. At the moment when the wheels 10, especially the rear wheels 10b, pass over the edge of the stairs, the center of gravity of the moving body can be quickly changed, and the moving body can be accelerated forward. The operation of the moving body climbing up the stairs according to the embodiment of the present invention can be understood as an operation to prevent the moving body from colliding with the stairs due to acceleration.

[0070] Figure 5 An example of control of a moving body according to an embodiment of the present invention is shown. Before the moving body encounters stairs, the moving body travels while the wheel 10 rotates at a reference rpm. When the wheel 10 rotates so that the body 20 moves forward, if the absolute value of the angular velocity of the body 20 is greater than the first reference angular velocity, the controller 30 may reduce the rpm of the wheel 10 (S200).

[0071] The first reference angular velocity may be a value of the angular velocity of the body 20 that may be exceeded at the moment when the wheel 10 passes over the edge of the stairs. For example, the moment when the absolute value of the angular velocity of the body 20 exceeds the first reference angular velocity may mean the moment after the wheel 10, especially the rear wheel 10b, has just climbed up the stairs.

[0072] If the absolute value of the angular velocity of the body 20 is not greater than the first reference angular velocity after the rpm of the wheel 10 is reduced, the controller 30 may increase the rpm of the wheel 10 until the rpm of the wheel 10 becomes the reference rpm.

[0073] Figure 6 An example of a situation immediately before the rear wheels of a moving object climb up stairs is shown. Figure 7 An example of a situation immediately after the rear wheels of a moving object have climbed up stairs is shown.

[0074] The process of the moving body climbing up the stairs can be understood as the process of the wheels 10 rotating so that the main body 20 moves forward. Hereinafter, the forward direction will be defined as the direction in which the main body 20 moves to climb up the stairs.

[0075] As described above, when the wheel 10 rotates so that the body 20 moves forward, if the absolute value of the angular velocity of the body 20 is greater than the first reference angular velocity, the controller 30 may reduce the rpm of the wheel 10 ( S200 ).

[0076] The moment when the absolute value of the angular velocity of the body 20 exceeds the first reference angular velocity may be the moment when the wheels 10 pass over the edge of the stairs. When the wheels 10, especially the rear wheels 10b, pass over the edge of the stairs, the center of gravity of the moving body may change rapidly, and the moving body may accelerate forward.

[0077] This is because the angle between the moving body and the ground is instantly greatly reduced at the edge of the stairs, so the absolute value of the angular velocity of the main body 20 may become greater than the specific first reference angular velocity.

[0078] Here, if the rpm of the wheel 10 is not reduced, the stairs and the moving body may collide with each other as the body 20 is accelerated. Therefore, the controller 30 may prevent the collision of the stairs and the moving body by reducing the rpm of the wheel 10.

[0079] As described above, if the absolute value of the angular velocity of the body 20 is not greater than the first reference angular velocity after the rpm of the wheel 10 is reduced, the controller 30 may increase the rpm of the wheel 10 until the rpm of the wheel 10 becomes the reference rpm. The situation that the absolute value of the angular velocity of the body 20 is not greater than the first reference angular velocity may mean a situation where the front wheel 10a passes over the edge of the stairs.

[0080] Therefore, the controller 30 can restore the rpm of the wheel 10 again after preventing the collision with the stairs due to instantaneous acceleration. The reference rpm may be the rpm of the wheel 10 of the moving body traveling on a flat surface, but the present invention is not limited thereto and may be a value that can be variously set according to user needs.

[0081] Meanwhile, the controller 30 may determine the first reference angular velocity through various methods. Hereinafter, an example of a method for determining the first reference angular velocity will be described in detail.

[0082] Therefore, the first reference angular velocity may have a value based on a value obtained by dividing the amount of change in the angle of the body 20 when the rear wheel 10b passes over the stair edge by the time period taken for the rear wheel 10b to pass over the stair edge.

[0083] As an example, the first reference angular velocity may have a value obtained by deriving a value obtained by dividing the amount of change in the angle of the body 20 when the rear wheel 10b passes over the edge of the stairs by the time period taken for the rear wheel 10b to pass over the edge of the stairs, and multiplying the value by a reference constant k. As an example, the reference constant k may be 0.7, however the present invention is not limited thereto and may be adjusted according to user needs.

[0084] First, an example of a method for deriving the amount of change in the angle when the rear wheel 10b passes over the edge of the stairs will be described in detail. As an example of the deriving method, the amount of change in the angle is derived under the assumption that the amount of change in the wheel 10b is ignored.

[0085] Figure 6 An example of a situation immediately before the rear wheels of a moving object climb up stairs is shown. Figure 6 , the angle a between the body 20 and the ground can be defined according to the following equation.

[0086] [Equation 2]

[0087]

[0088] Figure 7 An example of the situation immediately after the rear wheels of the moving object have climbed up the stairs is shown. Figure 7 In the embodiment, the angle a′ between the main body 20 and the ground can be defined according to the following equation: The value of Ry means the height difference between the center of the rear wheel 10b and the stairs with which the rear wheel 10b contacts.

[0089] [Equation 3]

[0090]

[0091] Meanwhile, the Ry value may be derived by combining the following two equations. In the following equation, the Rx value means the front-rear direction length difference between the center of the rear wheel 10b and the stairway with which the rear wheel 10b contacts.

[0092] [Equation 4]

[0093] L 2 =(H+R-Ry) 2 +(2W-R+Rx) 2, R 2 =Rx 2 +Ry 2

[0094] In the above equation, the values ​​of H, L, W, and R are all determined values, and therefore, the amount of change in the angle of the main body 20 can be derived from the above equation.

[0095] Figure 8 An example of the situation just before and just after the rear wheel climbs the stairs is shown. For reference, for ease of explanation, Figure 8 Only the rear wheel 10b is shown. Figure 8 , the time period t taken for the rear wheel 10b to climb the stairs can be defined according to the following equation.

[0096] Hereinafter, the time period t taken for the rear wheel 10b to climb the stairs is derived under the assumption that the movement of the rear wheel 10b climbing the stairs is a rotation of a point rotating theta around the edge of the stairs. In the process, the change of the rotation radius is ignored. In the following equations, rpm means the number of revolutions per minute of the wheel 10.

[0097] [Equation 5]

[0098]

[0099] In the above equation, the rpm value is a determined value and theta can be derived by the following equation.

[0100] [Equation 6]

[0101]

[0102] Therefore, the first reference angular velocity can be obtained as follows.

[0103] [Equation 7]

[0104]

[0105] Obviously, the above method is a simple example of obtaining the first reference angular velocity and the first reference angular velocity can be defined by various methods. As another example, the controller 30 can determine the first reference angular velocity based on the first length L1 and the second length L2. Then, the controller 30 can derive t by deriving theta from the first length L1 and the second length L2. In this process, the rotation radius can be considered as the constant second length L2.

[0106] An operation of the moving body according to the embodiment of the present invention to climb down stairs by moving backward will be described below. Figures 9 to 11 An example of a state in which a moving body moves backward and climbs down stairs is shown in sequence. For reference, for the convenience of illustration, Figures 9 to 11The wheel 10 is shown to be circular, but as described above, the shape of the wheel 10 may vary depending on the contact portion.

[0107] like Figure 5 As shown, when the wheel 10 rotates so that the body 20 moves backward, if the absolute value of the angular velocity of the body 20 exceeds the second reference angular velocity, the controller 30 may reduce the rpm of the wheel 10 (S400). As an example, the second reference angular velocity may have a value corresponding to the first reference angular velocity, but may be derived by a separate method.

[0108] The second reference angular velocity may be a value of the angular velocity of the main body 20 that may be exceeded at the moment when the wheel 10, especially the rear wheel 10b, falls over the edge of the stairs. For example, the moment when the absolute value of the angular velocity of the main body 20 exceeds the second reference angular velocity may be the moment when the wheel 10 falls over the edge of the stairs. At the moment when the wheel 10, especially the rear wheel 10b, passes over the edge of the stairs, the rear wheel 10b falls, and thus the center of gravity of the moving body changes rapidly, and the moving body may accelerate backward.

[0109] When the moving body passes the edge of the stairs, the angle between the moving body and the ground increases greatly instantaneously, so the absolute value of the angular velocity of the main body 20 may become greater than the specific second reference angular velocity.

[0110] Therefore, the controller 30 may reduce the impact applied to the body 20 due to the collision with the stairs by reducing the rpm of the wheel 10 .

[0111] When the wheel 10 rotates so that the body 20 moves backward, if the absolute value of the angular velocity of the body 20 is not greater than the second reference angular velocity after the rpm of the wheel 10 is reduced, the controller 30 may increase the rpm of the wheel 10 until the rpm of the wheel 10 becomes the reference rpm (S500). The situation that the absolute value of the angular velocity of the body 20 is not greater than the second reference angular velocity may mean a condition in which the rear wheel 10b has fallen. Therefore, the controller 30 may restore the rpm of the wheel 10 again after it has fallen.

[0112] Fig.12 Another example of the control of the moving body according to the embodiment of the present invention is shown. Hereinafter, another example of the control of the controller 30 will be described in further detail. Detailed description of the contents identical or corresponding to the existing control will be omitted.

[0113] The controller 30 may be configured to obtain an angle of the body 20 relative to the ground. When the wheel 10 rotates so that the body 20 moves forward, if the absolute value of the angular velocity of the body 20 is greater than the first reference angular velocity and the angle of the body 20 relative to the ground is the reference angle or greater, the controller 30 may reduce the rpm of the wheel 10 (S200').

[0114] When configured to acquire the angle of the body 20 with respect to the ground and add a condition that the angle of the body 20 with respect to the ground is not less than the reference angle, the controller 30 may prevent execution of control of reducing the rpm of the wheel 10 on a flat surface.

[0115] According to the present invention, since the rpm of the wheel is adjusted based on the change in the angular velocity of the main body occurring in the process of the moving body getting on and off the obstacle, the impact generated by the collision with the obstacle in the process of overcoming the obstacle can be reduced.

[0116] The present invention has been made to solve the above-mentioned problems.

[0117] Embodiments of the present invention provide a moving body that can reduce an impact caused by a collision with an obstacle during a process of going up and down the obstacle, and a method for controlling the moving body.

[0118] The technical problems to be solved by the present invention are not limited to the above-mentioned problems, and any other technical problems not mentioned herein will be clearly understood by those skilled in the art to which the present invention belongs from the following description.

[0119] According to an example of the present invention, a mobile body includes: a wheel, a body to which the wheel is coupled, and a controller coupled to the body and configured to control the movement of the wheel, the controller being configured to obtain an angular velocity of the body relative to the ground, and the controller controls the rpm of the wheel based on the angular velocity of the body.

[0120] In another example, the wheel may be formed such that a first length obtained by connecting a ground-contacting portion of the wheel and a center axis thereof when the wheel contacts the ground is smaller than a second length obtained as a length of a radius of the wheel when the wheel does not contact the ground.

[0121] In another example, when the wheel rotates so that the body moves forward, if the absolute value of the angular velocity of the body is greater than the first reference angular velocity, the controller may reduce the rpm (eg, rotation speed) of the wheel.

[0122] In another example, when the wheel rotates to move the body forward, if the absolute value of the angular velocity of the body is not greater than the first reference angular velocity after the rpm of the wheel decreases, the controller may increase the rpm of the wheel until the rpm of the wheel becomes the reference rpm.

[0123] In another example, the controller may be configured to obtain the angle of the body relative to the ground, and when the wheel rotates to move the body forward, if the absolute value of the angular velocity of the body is greater than a first reference angular velocity and the angle of the body relative to the ground is not less than a reference angle, the controller may reduce the rpm of the wheel.

[0124] In another example, the wheel may be formed so that a first length obtained by connecting a portion of the wheel that contacts the ground and a center axis thereof when the wheel contacts the ground is smaller than a second length obtained as a length of a radius of the wheel when the wheel does not contact the ground, and the controller may determine a first reference angular velocity based on the first length and the second length.

[0125] In another example, when the wheel rotates so that the body moves backward, if the absolute value of the angular velocity of the body is greater than the second reference angular velocity, the controller may reduce the rpm of the wheel.

[0126] In another example, when the wheel rotates to move the body backward, if the absolute value of the angular velocity of the body is not greater than the second reference angular velocity after the rpm of the wheel is reduced, the controller may increase the rpm of the wheel until the rpm of the wheel becomes the reference rpm.

[0127] In another example, the mobile body may also include a receiving portion coupled to the upper side of the main body, each of the wheels may include a front wheel coupled to the front side of the main body and a rear wheel coupled to the rear side of the main body, and the center of gravity of the main body may be formed on the upper side of the front wheel.

[0128] In another example, each of the wheels may include: a circular frame, a circular first impact absorbing member connected to the outer side of the frame, an annular second impact absorbing member spaced apart from the first impact absorbing member in a radially outward direction, and a third impact absorbing member connecting a point of the first impact absorbing member and a point of the second impact absorbing member.

[0129] In another example, the third shock absorbing member may be configured to elastically support the second shock absorbing member relative to the first shock absorbing member.

[0130] In another example, the third shock absorbing member may extend obliquely with respect to the radially outward direction between the first shock absorbing member and the second shock absorbing member.

[0131] In another example, the third impact absorbing member may be bendably extended.

[0132] According to another example of the present invention, a mobile body control method is provided for controlling a mobile body including a wheel and a main body to which the wheel is coupled, the mobile body control method comprising: obtaining the angular velocity of the main body, determining whether the magnitude of the angular velocity is not less than the magnitude of a specific reference angular velocity, and adjusting the rpm of the wheel based on the content of the determination step.

[0133] Although the present invention has been described with reference to limited embodiments and drawings in the above description, the above description is only an exemplary description of the technical idea of ​​the present invention, and a person skilled in the art to which the present invention belongs may make various corrections and modifications without departing from the essential features of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of ​​the present invention, but to illustrate, and the scope of the technical idea of ​​the present invention is not limited by the embodiments. The scope of protection of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent range should be interpreted as included within the scope of the present invention.

Claims

1. A device comprising: Multiple wheels; a body coupled to the plurality of wheels; as well as The controller is configured as: determining an angular velocity of the body relative to the ground; and The rotational speeds of the plurality of wheels are controlled based on the angular velocity.

2. The device according to claim 1, wherein: A wheel of the plurality of wheels is configured to dynamically shape with movement so that a first length of the wheel becomes smaller than a second length of the wheel, The first length is a first distance between: A first point of contact of the wheel with the ground; and The central axis of the wheel; and The second length is the second distance between: a second point of the wheel not in contact with the ground; and The central axis of the wheel.

3. The device according to claim 1, wherein: The plurality of wheels rotate so that the body moves forward, and wherein the controller is configured to reduce a rotation speed of the plurality of wheels based on an absolute value of an angular velocity of the body being greater than a first reference angular velocity.

4. The device according to claim 3, wherein: The rotation of the multiple wheels causes the body to move forward, and wherein the controller is configured to increase the rotation speed of the multiple wheels until the rotation speed of the multiple wheels reaches a reference rotation speed after the rotation speed of the multiple wheels decreases based on the absolute value of the angular velocity of the body being not greater than the first reference angular velocity.

5. The device according to claim 3, wherein: The controller is configured to determine an angle of the body relative to the ground, wherein the rotation of the multiple wheels causes the body to move forward, and wherein the controller is configured to reduce the rotation speed of the multiple wheels based on the absolute value of the angular velocity of the body being greater than the first reference angular velocity and the angle of the body relative to the ground being not less than a reference angle.

6. The device according to claim 3, wherein: A wheel of the plurality of wheels is configured to dynamically shape with movement so that a first length of the wheel becomes smaller than a second length of the wheel, The first length is a first distance between: A first point of contact of the wheel with the ground; and The central axis of the wheel; The second length is the second distance between: a second point of the wheel not in contact with the ground; and The central axis of the wheel; and Wherein, the controller is configured to determine the first reference angular velocity based on the first length and the second length.

7. The device according to claim 1, wherein: The plurality of wheels rotate so that the body moves backward, and wherein the controller is configured to reduce the rotation speed of the plurality of wheels based on an absolute value of the angular velocity of the body being greater than a second reference angular velocity.

8. The device according to claim 7, wherein: The controller is configured to increase the rotation speeds of the wheels until the wheels reach a reference rotation speed after the wheels decrease in rotation speed based on the absolute value of the angular velocity of the body being not greater than the second reference angular velocity.

9. The apparatus according to claim 1, further comprising: a receiving portion coupled to an upper side of the main body, Wherein, the plurality of wheels include: a front wheel coupled to the front side of the body; and a rear wheel coupled to the rear side of the body, Wherein, the center of gravity of the main body is formed on the upper side of the front wheel.

10. The device according to claim 1, wherein: Each of the plurality of wheels comprises: Circular frame; a circular first impact absorbing member connected to the outer side of the circular frame; an annular second impact absorbing member spaced apart from the circular first impact absorbing member in a radially outward direction; and The third shock absorbing member connects one point of the circular first shock absorbing member and one point of the annular second shock absorbing member.

11. The device according to claim 10, wherein: The third shock absorbing member is configured to elastically support the annular second shock absorbing member relative to the circular first shock absorbing member.

12. The device according to claim 10, wherein: The third shock absorbing member extends in an inclined manner in a radially outward direction between the circular first shock absorbing member and the annular second shock absorbing member.

13. The device according to claim 12, wherein: The third impact absorbing member extends in a curved shape.

14. A method comprising the steps of: determining, by a controller, an angular velocity of a body coupled to the plurality of wheels; Determining whether the magnitude of the angular velocity is not less than the magnitude of a reference angular velocity; as well as The rotational speeds of the plurality of wheels are adjusted based on a result of the determining step.

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