Rotary mechanism, flying body, payload posture control device, and method

Abstract

To provide such a mechanism or device that can increase the degrees of freedom in arrangement of the rotation center of a rotor relative to a rotation reference and to suppress change in posture of a flying body against pulling using the same.SOLUTION: In a rotation reference and a rotor: a link X and a link A are connected by a joint XA; the link A and a link B are connected by a joint AB; the link B and a link Y are connected by a joint BY; and a link C and a joint XC on the link X are connected by a joint BC on the link B. The rotation reference is connected to the link X, or the link X is the rotation reference and the rotor is connected to the link Y or connected by a rolling mechanism, where the link Y is the rotor.SELECTED DRAWING: Figure 15

Description

[Technical field]

[0001] This relates to rotation mechanisms, gimbals, and control of the position and attitude of rotating bodies, and flying bodies. [Background technology]

[0002] In recent years, development has been progressing to realize delivery using flying objects called drones. Most drones are configured with a control computer, battery, sensors, etc. near the center of the aircraft. Placing heavy components near the center of the aircraft during flight reduces the moment of inertia, which is advantageous for the aircraft's movement. Also, placing acceleration sensors and other components near the center of the aircraft is advantageous for control and sensing.

[0003] In order to reduce the loss of the aircraft or accidents caused by its out-of-control speed, some aircraft are equipped with a mooring cord or wire. Another method involves connecting a cord or wire to the aircraft and attaching a payload to the cord or wire to fly the aircraft suspended from the wire. Depending on the position of the mooring cord or wire, when the aircraft is pulled by the cord or wire, a force may be generated that rotates the aircraft, causing the aircraft to lose its attitude. For example, the cord may be pulled to retrieve the aircraft or to prevent it from moving in the event of an out-of-control speed. Also, when the cord or wire is blown by the wind, a pulling force may be generated that changes the aircraft's attitude. Even when a load is suspended by a cord or wire, the pulling force may cause the aircraft to lose its attitude. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2019-059480 Summary of the Invention [Problem to be solved by the invention]

[0005] The force that rotates the aircraft is suppressed when tension is applied to strings or wires connected to the aircraft. [Means for solving the problem]

[0006] The center of rotation of the rotating body relative to the rotation reference is set outside the mechanism structure by the link mechanism.

[0007] Link X and Link A are connected by joint XA. Link A and link B are connected at joint AB, Link B and link Y are connected at joint BY, Link C is connected to joint XC on link X and joint BC on link B, A rotation reference is connected to link X, or link X is a rotation reference, A rotating mechanism in which a rotating body is connected to link Y or link Y is the rotating body.

[0008] Link X and Link A are connected by joint XA. Link A and link B are connected at joint AB, Link B and link Y are connected at joint BY, Link C is connected to joint XC on link X and joint BC on link B, When looking at the joint in a plane perpendicular to the joint's axis of rotation, A line passing through joints XA and XC is parallel to a line passing through joints AB and BC. A mechanism in which joints are arranged so that a line passing through joints XA and AB is parallel to a line passing through joints XC and BC, A rotation reference is connected to link X, or link X is a rotation reference, A rotating mechanism in which a rotating body is connected to link Y or link Y is the rotating body.

[0009] The rotation mechanism may be connected to be rotatable in at least one axial direction relative to a rotation reference.

[0010] The link Y may be a string or a wire. In the case where the link Y is a string or a wire, the joint BY may be omitted. Alternatively, the joint BY may be considered as a position where the string or wire is attached.

[0011] A line passing through joints XA and XC is parallel to a line passing through joints AB and BC. When the line passing through joints XA and AB is parallel to the line passing through joints XC and BC, by positioning joint BY so that the positional relationship between joints AB, BC, and BY is the same as the positional relationship between joints XA, XC, and center O when pulling, the force when pulling will pass through center O. Center O can be thought of as the center of rotation of a string or wire. By using a parallel link mechanism, the center of rotation can be set to a point in the air.

[0012] An actuator may be provided so as to rotate link Y relative to link X. If any of the joints can be rotated or any of the links can be tilted, then the rotation mechanism can rotate link Y relative to link X.

[0013] Link X and link Au are connected at joint XAu. Link X and link Cu are connected at joint XCu. Link X and Link E are connected by joint XE. Link B and link Au are connected at joint AuB, Link B and link Cu are connected at joint BCu, Link B and link E are connected by joint BE, Link B and link Y are a rotation mechanism connected by joint BY.

[0014] A rotation reference is connected to link X, or link X is a rotation reference, A rotating body is connected to the link Y, or the link Y is the rotating body, forming a rotating mechanism.

[0015] Link X is connected to an air vehicle, or Link X may be an air vehicle. The link Y is connected to a string, wire, or the like, or the link Y may be a string, wire, or the like.

[0016] Each of the joints connects the connected links so as to be rotatable in at least two axial directions. The two axes of each joint may be in a positional relationship of translation. It is sufficient that the axis of rotation as a behavior can form a translational relationship. For example, if two axes intersect, they may rotate in the cross product direction of the two axes.

[0017] When the two rotation axis directions of the joint are viewed on perpendicular planes, The line passing through joints XAu and AuB, the line passing through joints XCu and BCu, and the line passing through joints XE and BE are parallel to each other, and the inter-joint distance is the same.

[0018] When the two rotation axis directions of the joint are viewed on perpendicular planes, The positional relationship between joint AuB and joint BY is set to be the same as the positional relationship between joint XAu and the center of rotation O. The center of rotation O can be thought of as the point through which a pulling force passes.

[0019] The rotation mechanism can be actively rotated by driving the rotation axis of one of the joints of each rotation axis of the rotation mechanism with an actuator or applying a force to rotate the rotating body to one of the links. It may also be rotated passively without applying a driving force.

[0020] A resistance force against the rotation of the rotation axis of at least one of the joints may be applied. One example of the effect is to suppress the swaying by suppressing the rotation caused by the swaying of link Y. The magnitude of the resistance force may be controlled so as to change based on conditions such as the amount of rotation or speed, the tension applied to the rotation mechanism, the force rotating the rotation mechanism, and the passage of time. For example, the resistance force can be controlled by providing a brake on the rotation axis. The resistance force may be friction, a spring, a damper, electromagnetic resistance, etc. Effect of the Invention

[0021] Since the pulling force of the string or wire passes through the center of rotation O, the force that rotates the rotation base when pulled can be suppressed.

[0022] By providing or controlling resistance to the rotation of the rotation axis, the swing of link Y and link X can be suppressed or controlled. [Brief description of the drawings]

[0023] [Figure 1] Rotation mechanism diagram [Diagram 2] Shape with the center of rotation shifted [Diagram 3] Example 1 of application to aircraft [Figure 4] Example 2 of application to aircraft [Diagram 5] Example 3 of application to aircraft [Figure 6] Horizontal installation example [Figure 7] Aircraft Hookup Examples [Figure 8] Application Examples [Figure 9] Another example of rotating link Y in two axes: [Figure 10] Another example 2 of rotating link Y in two axes [Figure 11] Example of configuration without link D [Figure 12] Example of a joint that rotates in two directions [Figure 13] Joint Variations [Figure 14]Link Variation 2 [Figure 15] Example of mooring rope installation [Figure 16] Mooring rope installation example 2 [Figure 17] Hollow shaft example [Figure 18] Hollow shaft example 2 [Figure 19] Redundant link example [Figure 20] Example of aircraft installation DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] FIG. 1 shows the basic configuration of the rotation mechanism of the present invention.

[0025] Link X1 and link A2 are connected at joint XA10. Link A2 and link B3 are connected at joint AB12, Link B3 and link Y6 are connected at joint BY15. Link C4 is connected at joint XC11 on link X1 and at joint BC13 on link B3.

[0026] A rotation reference is connected to link X, or link X1 is a rotation reference, Link Y is connected to a rotating body, or link Y6 may be a rotating body. The rotational reference may be a flying object. The rotating body may be a string or a wire. If the link Y6 is a string or a wire, the joint BY15 may be omitted. Alternatively, the joint BY15 may be considered as a position where the string or the wire is attached.

[0027] The load 101 may be connected to a link Y6, a string, or the like.

[0028] Here, the joints are capable of rotating the links connected to each other on parallel rotation axes. They may be considered as so-called slewing pairs.

[0029] When looking at the joint in a plane perpendicular to the joint's axis of rotation, The line connecting joints XA10 and XC11 is parallel to the line connecting joints AB12 and BC13. The link mechanism may be arranged so that the line connecting the joints XA10 and AB12 is parallel to the line connecting the joints XC11 and BC13. Even if the position of the joint changes in the depth direction, it is equivalent in the link mechanism.

[0030] With this configuration, link Y6 can rotate around the center of rotation O relative to link X1. Link Y6 can rotate around the center of rotation O without placing a component for rotation, such as a joint, at the center of rotation O. Here, the rotation axis of link Y6 is parallel to the rotation axis of the joint. An example of the state of rotation is shown in (a) and (b) of Figure 1. However, here, link X is shown as rotating around the center of rotation O relative to link Y.

[0031] Any modification that satisfies the conditions for the position of each joint may be used without being limited to the configuration exemplified in Fig. 1. For example, link A2 and link C4 may be located on the left and right sides of center O, or on one side.

[0032] Furthermore, the position of the center of rotation O at this time is determined so that, when the joints are viewed on a plane perpendicular to the rotation axes of the joints, the positional relationship between joints XA10, XC11 and the center of rotation O is the same as the positional relationship between joints AB12, BC13 and BY15. In other words, by designing the position of joint BY15 relative to joints AB12 and BC13, it is possible to obtain the center of rotation O at any position.

[0033] The links may be arranged with a shift in the depth direction and in the direction of the rotation axis so as to avoid interference between the links.

[0034] In Figure 1, each link is configured as a straight line, but as long as the positional relationship of the joints satisfies the above conditions, the shape is not important. Therefore, to avoid interference between links or collisions with their connections, the links may be configured with bends to ensure a wide range of motion, or the joints may be located in the depth direction.

[0035] 2, the position of the center of rotation O can be changed by shifting the position of the joint BY15. As a result, for example, when the link X1 is connected to the bottom surface of the aircraft 100, the center of rotation O can be positioned above the bottom surface.

[0036] By further rotating this rotation mechanism about another axis, link Y6 can be rotated on two axes, the rotation axis of the rotation mechanism and the rotation axis that rotates the rotation mechanism. For example, in FIG. 1, link X1 is rotated on an axis parallel to the line connecting joints XA10 and XC11. Here, by setting the rotation axis that rotates link X1 to an axis passing through the rotation center O, link Y6 can be rotated in two directions around the rotation center O. An example of a method for connecting link X1 to a rotation reference is to connect link X1 to the rotation axis of link X1 using a motor, bearings, etc. so that link X1 can rotate with respect to the rotation reference.

[0037] FIG. 3 shows an example of an aircraft 100 equipped with a rotation mechanism. When the rotation mechanism of the present invention is applied to an existing aircraft, the rotation mechanism of the present invention is connected to the bottom, side, top, etc. of the aircraft. FIG. 3 shows an example in which link X1 is connected to the side of the aircraft 100 so as to be rotatable in the x-axis direction. The rotation mechanism rotates link Y6 in the z-axis direction. The center of rotation of the aircraft 100 is point O inside the aircraft 100.

[0038] As shown in Figure 3, the rotation axis of link X1 is connected to pass through the rotation center O of the aircraft. This makes it possible to offset the rotation of the payload 101 relative to the rotation of the aircraft 100 in the x-axis direction by rotating link X1. Each joint in Figure 3 allows the link connected in the z-axis direction to rotate.

[0039] Fig. 4 shows another example of an aircraft 100 equipped with a rotation mechanism. Link X1 is divided into a left side and a right side, and the link X1 is connected to both sides of the aircraft 100. In the example of Fig. 4, link X1 connected to link A2 is connected to the left side of the aircraft, and link X1 connected to link C4 is connected to the right side. The two links X1 are rotatable on the same axis in the x-axis direction.

[0040] Compared to the configuration in Figure 3, the configuration in Figure 4 has an advantage in terms of load resistance because it has more connection points with the aircraft. It is also advantageous in terms of balance because it can be configured symmetrically.

[0041] FIG. 5 shows another example of a method for connecting link X1. Link X1 is connected so as to be rotatable about an axis passing through rotation center O in the x-axis direction. Here, joints XA10 and XC11 can be installed at a position that is not on the rotation axis of link X1. In this case, in order to make the rotation center of link Y6 the rotation center O, the positional relationship between joints AB12, BC13, and BY15 when viewed on the xy plane is set to be the same as the positional relationship between joints XA10, XC11, and rotation center O. A similar configuration can also be used when connecting only one side, as shown in FIG. 3.

[0042] In the configuration of Fig. 5, by changing the shape of the link X1 as in (a) and (b), application to aircraft 100 of different sizes becomes possible. Therefore, the rotation mechanism can be changed by simply replacing the link X1 according to the aircraft 100 to which it is applied. Alternatively, by making the length of the link X1 in the x-axis direction variable, it can be attached to aircraft 100 of various sizes. By making the positions of the joints BY15 and DY16 variable, the position of the rotation center O can be changed, further improving the degree of freedom in application.

[0043] The main difference between Figure 4 and Figure 5 is the movable range of link A2 and link C4. The configuration of Figure 4 and the configuration of Figure 5 can be used selectively so as not to impede the function of the target component, such as an aircraft.

[0044] An example of a method for driving the rotation mechanism will be described.

[0045] Any of the joints of each rotation mechanism may be driven by a motor or the like. In addition, by providing any of the joints with a sensor that measures the amount of rotation and the rotation angle of the joint, a system for controlling the attitude of the rotating body can calculate the attitude of the rotating body with respect to a rotation reference. Examples of the sensor include a rotary encoder and a potentiometer. When an actuator that rotates to a target angle, such as a servo motor, is used as the motor, the target amount can also be treated as the amount of rotation. The amount of rotation may be calculated using the target amount.

[0046] An arm that can be driven by an actuator may move any of the links of each of the rotation mechanisms.

[0047] In a configuration with multiple rotation axes, such as a configuration using multiple rotation mechanisms, applying a force to move the link Y connected to the rotating body or the rotating body results in a rotational motion around the rotation center O. If any of the links connected to the rotating body can be driven in two directions, it becomes possible to control the rotation of the rotating body around the rotation axis O.

[0048] An example of the configuration when driving by an arm is shown in Fig. 1. An actuator 31 that drives an arm 30 is mounted on link X1 or a rotation reference, and is connected to link C4 by a driving link 32. Of course, it is also possible to drive a link other than C4.

[0049] When rotating in two axial directions, by using a spherical joint or a rotating and sliding joint to connect the arm 30, the drive link 32, and the link C4, it is possible to accommodate position changes in the direction of the rotation axis, so that, for example, even when one rotation mechanism is rotated by another rotation mechanism, the actuator 31 can be installed on the first link X1 or the rotation reference.

[0050] The amount of rotation of the link Y by the rotation mechanism may be obtained by providing a sensor at the joint to obtain the amount of rotation. Alternatively, the amount of rotation of the link Y relative to the rotation of the arm may be calculated. This can be calculated from the length of the arm, the amount of rotation, and distance information between each joint.

[0051] As an example, if the center of rotation of arm 30 is placed on a line passing through joints XA10 and XC11 and the drive link is parallel to XA10-XC11, the amount of rotation of the arm becomes the amount of rotation of link Y6 directly, reducing the calculation load.

[0052] The length between the joints of the driving link 32 in Fig. 1 may be changed. The driving link 32 may be made extendable or the position of the joint may be made movable by a slider. In this case, the arm 30 may be fixed, or the arm 30 may be eliminated and the driving link 32 may be connected to the link X1.

[0053] The length between the joints XA10-AB12 and between the joints XC11-BC13 may be changed during flight. If the distance between the bottom surface of the flying vehicle 100 and the link B3 during flight 100 changes and becomes longer, the size during flight can be reduced by shortening that distance.

[0054] The position of each joint in the rotation mechanism may be variable. One example is that the length of the link between the joints can be changed. One example of a configuration in which the length can be changed is to place the joints of the link on a slider whose movement can be locked. Another example is that part of the link may be configured with a screw, and the distance between the joints may be adjusted by how tightly the screw is tightened. It may also be considered that the joints are connected with male and female threads so that the distance between the joints can be changed.

[0055] A rotation mechanism may be assembled by preparing multiple candidates for joint positions and selecting the joint position to be used when connecting to the rotation base according to the size of the rotation base and the position of the rotation center O. For example, multiple holes that serve as joints are provided in each link, and the hole to be used is selected according to the size of the aircraft and the position of the rotation center O, and the links are connected to each other with screws, rivets, etc. so that they can rotate around the hole.

[0056] In particular, by making it possible to change the position of joint BY relative to joint AB, and joint DY relative to joint AD, it becomes possible to change the position of the rotation center O of the rotation mechanism, making it applicable to various flying objects. It also becomes possible to change the flying object.

[0057] In the rotation mechanism of the present invention, all joints can be configured as rotating pairs, which is advantageous in terms of load resistance compared to a configuration that uses a spherical pair such as a ball joint. In addition, the configuration can be relatively simple.

[0058] Compared to conventional gimbals, the rotation mechanism of the present application does not require the rotating object, such as a camera (the rotation reference in this application, the flying object), to be configured to fit inside the gimbal, thereby reducing the overall size.

[0059] The rotation mechanism and each rotation shaft may be configured not to be driven by a motor or actuator. In this case, the force pulling the flying object due to the weight or swinging of the payload will not generate a force to rotate the flying object because the rotation mechanism and the rotation shaft rotate passively. At least one of the rotation shafts may be equipped with a means to prevent rotation.

[0060] An example of mounting the rotation mechanism of the present invention sideways is shown in Fig. 6. In the example of Fig. 6, the link X is connected to the upper and lower parts of the flying object, but the rotation mechanism may be mounted on the side of the aircraft to which it is attached. In this case, the rotation mechanism shown in Fig. 5 or the like can be used. An additional rotation axis may be added to rotate the rotating body on an axis other than that of the rotation mechanism. For example, the rotating body or flying object is connected to the rotation mechanism by a passively rotatable bearing or a rotation axis that can be driven by a motor or the like.

[0061] A counterweight may be provided on at least one of link A and link C. In the example of Fig. 6, counterweight 1500 is provided on link A. It may also be distributed and disposed on link C. By using counterweight 1500 to balance the rotation moment at rotation axis 0, it is possible to suppress the force that rotates the rotating mechanism or the rotating mechanism, which is generated by the weight of the string or the like. The counterweight 1500 may be a part of the configuration of the flying object 100. For example, the battery of the flying object 100, or in the case of an engine-type flying object, a fuel storage unit or a computer may be used. In particular, the battery is detachable in a general flying object and is a relatively heavy component, so it is suitable. The counterweight 1500 can be balanced with a heavier load 101 by being placed away from the center of rotation using the principle of leverage. By making the link A long or changeable, or by providing multiple candidates for the connection position of the counterweight 1500, the position of the counterweight 1500 can be changed, so that it can accommodate loads 101 of various weights. The weight of the counterweight 1500 may be changed.

[0062] As an example of how to determine the position of the counterweight 1500, when a counterweight is provided on link A, the moment of the force due to gravity of the counterweight 1500 around joint XA should be balanced with the moment of the force due to gravity of the string around the center of rotation O. It is also possible to cancel out the moment of force due to the weight of the rotating mechanism, etc.

[0063] The mounting of the rotation mechanism of the present invention to an aircraft will be illustrated. As shown in the example of FIG. 7 (a: front, b: top), a connection part 1700 for connecting to the aircraft is provided. The connection part 1700 of this example is fixed by sandwiching the fuselage of the aircraft 100. The connection part 1700 and the fuselage of the aircraft 100 may be fixed with a screw 1701. The fuselage of the aircraft 100 may be provided with a screw hole for fixing, or may be simply sandwiched with a screw. In this case, a non-slip rubber or the like may be provided to fix the screw and the fuselage. The fixing position of the fuselage may be adjustable so that the center of rotation of the aircraft 100 and the center of rotation of the rotation mechanism are aligned. A spacer may be used in this case. The fixing method is not limited to a screw. The connection part 1700 and the left and right links X1 are connected to be rotatable on the same rotation axis, and at least one of them is connected to be rotatable and driven by an actuator such as a motor. The connection part 1700 may be configured to be placed over the aircraft. It is expected that the required connection strength of the connection part 1700 can be reduced. Of course, it may be connected to the bottom of the aircraft.

[0064] The rotating body may be a crane or a winch. It may be considered that a wire, a string, or a chain is attached to the link Y. An example is shown in FIG. 8. By rotating the link Y6 with the rotation mechanism of the present invention, it is possible to suppress the influence of the swaying of the wire 1810, etc. on the flying object, or to control the swaying. When the rotation mechanism of the present invention is used, the direction of the wire 1810, etc., when pulled can be made to pass through the center of the flying object. For example, when the wire 1810 is stretched taut, an extension line of the straight line formed by the wire 1810 passes through the center of the flying object with the rotation center 0 of the rotation mechanism as the center of rotation of the rotation mechanism. By using such a configuration and control, it is possible to prevent the force of pulling the wire, etc. from generating a force that rotates the flying object. The direction from the rotation center 0 of the rotation mechanism to the connection point 1811 of the wire, etc. of the link Y, and the payout point 1811 of the winch, etc. may be controlled so that the direction is the same as the direction in which the wire, etc., pulls the link Y. When a winch is used, it is sufficient that the payout position of the wire, etc. is on the link Y, and the winch winding device may be arranged on the flying object side. The winch may be on the ground side when the load is suspended or when the load is moored. The wire or string 1810 may be a power supply cable for the aircraft or a communication cable.

[0065] Another example in which the link Y rotates in two axial directions is shown.

[0066] Link X701 and link Au702 are connected by joint XAu (710 and 810), Link X701 and link Cu705 are connected at joint XCu (711 and 811), Link X701 and link E708 are connected at joint XE (712 and 812), Link B704 and link Au702 are connected at joint AuB (713 and 813), Link B704 and link Cu705 are connected by joint BCu (717 and 817), Link B 704 and link E 708 are connected at joint BE (715 and 815), Link B 704 and link Y 709 are connected by a joint BY (719 and 819) to form a rotation mechanism.

[0067] A rotation reference is connected to the link X 701, or the link X is the rotation reference; A rotating body is connected to the link Y 709, or the link Y is a rotating body in the rotation mechanism. The rotation body and the rotation reference may be assigned inversely.

[0068] Link X 701 is connected to an air vehicle, or Link X may be an air vehicle. The link Y is connected to a string, wire, or the like, or the link Y may be a string, wire, or the like. In the case where the link Y is a string, wire, or the like, the joint BY may be omitted. Alternatively, the joint BY may be considered as a position where the string or wire is attached.

[0069] Each of the joints connects the connected links so as to be rotatable in at least two axial directions. The two axes of each joint may have a positional relationship of translation. It is sufficient that the axis of rotation as a behavior constitutes a translation relationship. For example, if two axes intersect, they may rotate in the cross product direction of the two axes. In another example, if multiple axes can be taken, it is sufficient that the representative two axes satisfy the above-mentioned translation relationship.

[0070] When the two rotation axis directions of the joint are viewed on perpendicular planes, The line passing through joint XAu (710, 810) and joint AuB (713, 813), the line passing through joint XCu (711, 811) and joint BCu (714, 814), and the line passing through joint XE (712, 812) and joint BE (715, 815) are parallel, and the distance between the joints is the same.

[0071] A joint that rotates in two directions may be as shown in Figures 12(a) and (b). As shown in Figure 12(a), link 2301 and link 2303 may be positioned on a straight line, or as shown in Figure 12(b), link 2301 and link 2303 may be connected by a curved axis (2305). Here, the joint only needs to be able to rotate the connected links in two axial directions, so it goes without saying that various means can be used, not limited to those shown here.

[0072] In the rotation mechanism of the present invention, it is sufficient that the amount of rotation by the joints about each rotation axis is the same. Therefore, for some joints, for example, the part 2305 of the joint may be made common and the rotation axis for the link may be omitted. When the rotation axes of the joints overlap when viewed in the rotation axis direction, the part 2305 of the joint may be made common.

[0073] A modified example of the joint is shown in Fig. 13. As shown in Fig. 13(a), when the rotation axis 2811 of the joint 2810 and the rotation axis 2821 of the joint 2820 are the same axis when viewed as the rotation axis in terms of behavior, By standardizing part 2810 having the joint axis and part 2820 having the axis and transforming them into part 2830 having the joint axis, the physical rotation axis 2811 and rotation axis 2821 can be standardized into rotation axis 2831, thereby reducing the number of parts. In other words, the remaining rotation axis also functions as one of the rotation axes. It may be considered that the rotation axis in one axial direction of joint 2810 and joint 2820 is shared. Joint 2830 is provided with rotation axis 2812 and rotation axis 2822 that are not shared between joint 2810 and joint 2820. 13 may be considered to be at least one of links X, B, and D. Naturally, similar modifications are possible for other links and joints as long as they satisfy the above-mentioned axial conditions. Link 2802 and link 2803 may each be considered to be any of the links connected to link 2801. For example, in the example of FIG. 10, if link 2801 is link X, then link 2802 and link 2803 are any combination of links A, E, or C. In the example of Figure 13, the position of the rotation axis changes between (a) and (b), but the shape and arrangement of the link may be changed so that it does not change. As shown in Figure 13 (c), a physical rotation axis 2831 may be connected to joints 2830 on both sides of a link 2801. The real axis may be separated on the left and right. Reducing the number of parts often leads to reducing weight, which is beneficial when applied to aircraft.

[0074] As a result of the above, at least one of the two joint axes will be the same as the rotation axis of the rotation mechanism. For at least one pair of joints, the parts of the joints having the same rotation axis can be combined into one to obtain a rotation mechanism with the same rotation axis as one rotation axis.

[0075] When the two rotation axis directions of the joint are viewed on perpendicular planes, The positional relationship between joint AuB (713, 813) and joint BY (719, 819) is set to be the same as the positional relationship between joint XAu (710, 810) and rotation center O (722, 822). If the rotation axis of joint BY (719, 819) does not intersect, the rotation axis of rotation center O does not intersect either, and becomes a rotation axis translated parallel to the rotation axis of joint BY (719, 819).

[0076] The rotation mechanism can be actively rotated by driving the rotation axis of one of the joints of each rotation axis of the rotation mechanism with an actuator or applying a force to rotate the rotating body to one of the links. It may also be rotated passively without applying a driving force. Also, the rotation axis may be provided with a means to prevent rotation.

[0077] As long as the conditions for the joint placement are met, the shape of each link does not matter. For example, the link can be curved so as not to interfere with the link movement. Also, links and joints may be added so as not to interfere with the movement of the rotation mechanism. For example, an additional link equivalent to link A can be added in a position different from the original link A. In this case, the added link will satisfy the same conditions as the placement and joint conditions of the original link A. Links C and link E may also be added in a similar manner. By adding links and joints, it is expected that the load-bearing capacity and rigidity of the rotation mechanism can be improved.

[0078] An embodiment is shown in Figures 9 and 10. This embodiment illustrates an example in which link Y is rotated in two axial directions. There are no restrictions on the shape and arrangement of the links, the arrangement of the joints, or the way the axes are taken, and any modification can be made. For example, the shape of the links can be changed to increase the movable range of the links.

[0079] In the example of FIG. 9, when viewed on the xy plane, the rotation axis of each joint is parallel to the z axis. When viewed on the yz plane, the rotation axis of each joint is parallel to the x axis. In the example of FIG. 9, the z axis and x axis rotation axes of each joint are arranged to intersect, but they may be configured so that they do not intersect, for example, all z axis rotation axes may be shifted upward by 1 cm. In this case, the rotation center Oz722 of the rotation mechanism will also be shifted upward by 1 cm, and Oz722 and Ox822 will not intersect. The orientation relationship between the z axis and x axis rotation axes of the joints does not have to be the same, but it is preferable that they are vertical or close to vertical.

[0080] In the example of Figure 9, when looking at the rotation axis of the joint in the z-axis direction, the distances between joints XAu710 and AuB713, between XE712 and BE715, and between XCu711 and BCu714 are the same, and the lines connecting each are parallel. When looking at the joint rotation axis from the x-axis direction, it is the same as when looking at the rotation axis from the z-axis direction. For simplicity of explanation, here, the joint code is increased by 100, such as the z-axis rotation axis XAu710 corresponding to the x-axis rotation axis XAu810.

[0081] When viewed from the z-axis direction, the z-axis rotation axis Oz722 of the rotation center O of the rotation mechanism is Oz722 such that the direction and distance from joint XAuz710 to the rotation center Oz722 are the same as the distance and direction from joint AuBz713 to BYz719. When viewed from the x-axis direction, the x-axis rotation axis Ox822 of the center of rotation O of the rotation mechanism is Ox822 such that the direction and distance from joint XAux810 to the center of rotation Ox822 are the same as the distance and direction from joint AuBx813 to BYx819. The center of rotation O of the rotation mechanism can be set by the distance and direction from joint AuB to BY.

[0082] At least one of the distance and direction from joint AuBz713 to BYz719 and the distance and direction from joint AuBx813 to BYx819 may be changed. For example, links B and D may be bent in at least one axial direction at point 2900 in FIG. 9, or may be stretchable so that the distance from point 2900 to joints BY and DY can be changed. Bending and stretching may be fixed so as not to move after adjustment. Also, they may be driven by an actuator. If they are driven by an actuator, it becomes possible to actively change the center of rotation while the rotation mechanism is in use. Any bending, stretching, and driving method may be used. A link or joint equivalent to link Y may be added between point 2900 and joints BY and DY. This may prevent the link conditions of the rotation mechanism from being not satisfied when bending or stretching.

[0083] In the example of Fig. 9, when the position of each joint is the intersection of two axes or a representative point that is in the same position relative to the positions of the two axes, the positions of the joints XAu (710, 810), XCu (711, 811), and XE (712, 812) of the link X701 form a triangle. Although the link Y709 in Fig. 9 is located outside the triangle, it may be located inside as in Fig. 10.

[0084] In an example of application to an aircraft, particularly when a wire or the like is connected to the aircraft as shown in Figure 8(b), when the wire is pulled, the force passes through or near the center of rotation O, so that changes in the aircraft's attitude due to the pulling can be suppressed.

[0085] When rotating about two axes, the link X1 may be made rotatable as shown in FIG. 4, or at least the joints XA10 and XC11 may be made rotatable about another axis.

[0086] At least a portion of link A, link C, and link Y may be made of a flexible material. For example, they may be string, thread, wire, or chain. In this case, the joints connecting the links made of a flexible material may be eliminated. Links that were connected by joints may be considered to be directly connected. The flexible material acts as a joint. When link Y is pulled relative to link X, link A and link C, which are made of a flexible material, are pulled and function as a rotation mechanism. In an example applied to the configurations of Figures 9 and 10, link E may also be made of a flexible material.

[0087] When link A and link C are made of a flexible material, the total length of the links may be shorter than the length between the connection points of the two links and link X. This makes it possible to prevent link A and link C from twisting. The lengths of link A and link C may each be shorter than the length between the connection points of the two links and link X.

[0088] An example of application to an aircraft is shown below. Figure 11 shows an example of connecting a wire or the like to an aircraft. Here, link Y6 is a wire, rope, string, or the like. A load may be connected to the end of the rope, or the rope may be connected to the ground or a winch to limit the flying range of the aircraft. At least one of the joints may be actively rotated by an actuator, or the like, to control the swing of link Y6.

[0089] In (a) of Fig. 11, the rotation center 2200 of the rotating body 1 and the rotation center 0 of the rotation mechanism are aligned. In an example of application to an aircraft, the direction of tension caused by pulling the rope faces the rotation center 2200 of the rotating body, so that the attitude change of the aircraft caused by pulling can be suppressed. Also, the aircraft can take any attitude without being pulled.

[0090] In FIG. 11(b), the center of rotation 0 of the rotation mechanism is set lower than the center of rotation 2200 of the rotating body 1. In the example of FIG. 11(b), the flying body is the link X1, and the joints XA10 and XC11 enable the links A2 and C4 to rotate in the depth direction as well. In an example applied to an flying body, the rotation mechanism can be attached to the bottom surface of the flying body. This makes it difficult for ropes and the like to get entangled in the propeller. The center of rotation 0 is set lower than the center of rotation 2200 of the rotating body, but it is preferable to have the centers of rotation 0 and 2200 close to each other.

[0091] In FIG. 11(c), the center of rotation 0 of the rotation mechanism is placed at a position higher than the center of rotation 2200 of the rotating body 1. When a rope or the like that serves as link Y6 is pulled, the tension of the rope generates a force that rotates the rotating body 1, tilting it in the direction of the pull. In a configuration in which an aircraft flying in the tilting direction of the aircraft is fixed to a fixed point with a rope or the like, the aircraft will tilt in the direction of the pull when pulled by the rope or the like. As a result, the aircraft will fly in the direction in which the rope or the like slackens. In the case of a multi-rotor type aircraft, the center of rotation 0 of the rotation mechanism can be placed at a higher position by connecting it to the outside of the propeller guard, etc.

[0092] Link A2 and link C4 may be made of ropes or strings. In this case, joints XA10, XC11, AB12, and BC13 may be omitted. Link X1, which is the flying object, and link B3 may be connected to each other by two ropes or strings to form a parallelogram, and link Y6 may be connected to link B3. If link Y6 is made of ropes or strings, joint BY15 may be omitted. The ropes or strings and the links may be connected by simply tying, so link B3, which is a rod-shaped object, and two strings or ropes may be used to easily form link Y. If link Y6 is a string or rope, link B3 may be connected to a rope or string to form link Y. If link Y6 does not need to be rotated strictly around the center of rotation 0, it is not necessary to connect link Y6 to form a parallelogram as described above, and link Y may be connected to form a rectangle. Of course, it is preferable to connect link Y6 to a parallelogram.

[0093] It is sufficient that at least links A2 and C4 are rotatable in at least two directions relative to link X. At joints XA10 and XC11, they may rotate in two axial directions, or as in the example of Figure 4, link X1 may be connected in an additional axial direction. When the rotation mechanism is passively rotated, it may rotate in three axial directions. That is, they may be connected with a flexible material as described above, or with a three-axis joint.

[0094] In addition to ropes, power supply wires and communication cables may be used. The aircraft can be retrieved by winding up wires or ropes, and the change in attitude of the aircraft caused by the tension generated by winding up can be suppressed. This can improve flight efficiency and reduce the risk of crashing due to winding up. It can also be used when towing cargo with the aircraft. In addition, dampers, springs, and elastic bodies may be provided on the ropes, etc. This can prevent sudden force from being applied to the aircraft, such as when tension is applied to a slack rope.

[0095] The mooring wire and the flying object may be connected by this rotation mechanism. In this case, any of the rotation mechanisms described above may be used.

[0096] FIG. 15 shows another example of connecting a wire, string, or rope to the aircraft. FIG. 15(a) shows an example in which a rotation mechanism is connected so that a link X1 can rotate on an axis passing through the rotation center 0 of the aircraft 100. By connecting a string, wire, or rope (6) to the joint BY15, the force of pulling the string (6) passes through the rotation center 0, and the force that rotates the aircraft 100 can be suppressed. The position of the joint BY15 can be arranged so that the positional relationship between the joints XA10 and XC11 and the rotation center 0 is the same as the positional relationship between the joints AB12, BC13, and BY15. FIG. 15(b) shows an example in which the link X1 is attached to the upper part of the aircraft 100. This is effective in cases where a sensor or camera is located at the bottom of the aircraft 100 and the rotation mechanism gets in the way of the sensor or camera.

[0097] The link may be bent as shown in Fig. 16. This allows the joint BY15 to be moved to a higher or lower position while avoiding interference with the flying body 100.

[0098] Link Y6 may not be a string, but may be a rod or other component that is hard to bend, and a string or the like may be connected to the end of link Y6. Keep the flexible part of the string or the like away from the rotation mechanism and the flying object to prevent entanglement.

[0099] As shown in FIG. 17, the flying object 100 and the link X1 may be connected using a hollow rotating shaft 103. The upper view of FIG. 17 is a view from the bottom, and the lower view is a view from the side. If a sensor or camera is present at the bottom of the flying object 100, the rotating mechanism may block the sensor or camera. By using the hollow rotating shaft 103 and allowing it to rotate around the rotation center 104, it is possible to rotate the rotating mechanism without blocking the camera or sensor located in the hollow part. An example of the shape of the links A2 and C4 in this case is shown in the link A2 in FIG. 17.

[0100] 18, link X1 may be disposed at a position shifted from the center of rotation 104 when viewed from the side. In this case, if the center of rotation of link Y6 is to intersect with the center of rotation 104, the position of joint BY15 should be set so that the positional relationship between joints AB12, BC13, and BY15 is the same as the positional relationship between joints XA10, XC11, and the center of rotation, as shown in the figure.

[0101] The movable range of each joint may be limited. For example, in the case of an aircraft, the rotation range of the rotation mechanism may be limited so that the link does not hit a driving part such as a propeller. A stopper may be provided to limit the movable range of the link.

[0102] The flying object 100 may be controlled to increase its altitude in an emergency. An emergency may be when communication with a user or a control system is cut off, or when a certain condition is met or when a certain condition is no longer met, such as when an abnormality is detected in an internal diagnostic system. As the flying object 100 rises, tension is maintained in the string or wire connected to the flying object, and the flying object can be pulled by pulling the wire or rope. As the flying object 100 rises, the altitude of the flying object can be controlled by pulling the string or the like. In addition, the position of the flying object approaches directly above the point where the user, winch, or the like is pulling the string, due to the pulling caused by the flying object's ascent and the pulling from the ground side, such as a user or winch. The flying object can be retrieved by pulling the string or the like.

[0103] The ascent operation may be performed when there is tension in the string or when the tension is equal to or greater than a predetermined value. The rotating mechanism, the string, the link Y6, etc. may be provided with a means for detecting the strength or presence of tension. If there is no tension, it may be that the string, etc. is not pulled properly, so by performing ascent only when there is tension, it is possible to prevent the flying object from being lost.

[0104] The ascent and descent may also be controlled according to the direction of the string. For example, if the string is pointing downward, it may be determined that the aircraft is above the mooring point and may begin descending and landing. If the angle of the string relative to the increasing direction is greater than a certain value, the aircraft may be made to ascend. Ascent and descent may be reversed.

[0105] The movement of the aircraft may be controlled by pulling a string or rope. For example, the movement of the aircraft in response to the pulling action may be set such that the aircraft will rise when the string is pulled strongly a predetermined number of times. The movement of the aircraft may be controlled according to the strength, number of pulls, timing, pulling direction, and combinations or sequences of these. Pulling may be considered as treating it as a command. In cases such as when a user holds a string connected to the aircraft 100 in his / her hand, it may be difficult to operate the controller. By using the pulling action as a substitute for the controller, it is possible to both tether and control the aircraft. In the case of using a rotation mechanism such as that shown in FIG. 11, it is possible to prevent the attitude of the aircraft from being lost due to the pulling action. The action of the aircraft may be not only rising, but also descending, moving forward, moving backward, moving left and right, turning, returning, and other actions other than those listed here.

[0106] As shown in FIG. 19, redundant links and joints that do not impede the rotation of the rotation mechanism may be provided. In the example of FIG. 19(a), a link 105 and joints 106 and 107 that connect the link 105 to the link A2 and the link C4 are added. When the joints 10, 11, and 13 are positioned in a straight line, the line connecting the joints 10 and 11 and the line connecting the joints 12 and 13 are prevented from becoming non-parallel. In the example of FIG. 19(b), a redundant link 108 that is connected to the links X1 and B3 that correspond to the link A2 is added. By making the positional relationship of the joints 10, 11, and 109 form a triangle, the line connecting the joints 10, 11, and 13 are prevented from becoming non-parallel when the joints 10, 11, and 13 are positioned in a straight line.

[0107] FIG. 20 shows an example of a method of attaching the aircraft to the rotation mechanism. The link connection part 112 is rotatably connected to the link X1. The link connection part 112 is connected to the arm part 111 of the aircraft as shown in FIG. 20(b). In the example shown in the figure, it is connected to the left and right positions in the nest, but it may be connected to the top and bottom positions in the figure. The arm part 111 of the aircraft is rarely equipped with equipment and is often empty space, so the connection method shown in FIG. 20 is effective. In addition, since the link X1 can be placed at a position away from the aircraft body, it is also effective in widening the movable range of the link. By making the length of the link connection part 112 sufficiently long, it can be attached to aircraft of various sizes.

[0108] At least one of the rotation axes, or the rotation axis of the joint, may be provided with a means for preventing rotation. A resistance force or the like may act in a direction that attenuates the rotating force, thereby suppressing the swinging of link Y and the like. One example of the means for preventing rotation is friction. For example, friction may be generated by the degree of contact between the links at the rotation axis of the joint. The resistance force against rotation may be adjustable by the tightening of screws or the like. The rotation axis itself may be provided with a means for preventing rotation, or the means for preventing rotation may be connected so as to move in conjunction with the movement of the link.

[0109] The means for preventing rotation may be a spring or a damper, or a combination of these including friction. A rotary damper may be used, or the damper may be connected to drive the damper, such as by changing its length according to the movement of the link. The same applies to springs. The natural frequency of the link Y may be designed to respond to the vibration, and the movement of the rotating mechanism may be adjusted to respond to the vibration. Actuators such as electromagnetic brakes and motors may be used for control.

[0110] The resistance force may be changed according to the rotation angle of the rotation axis. For example, the resistance force may be increased when the rotation amount of the rotation mechanism is near 0, and decreased as the angle increases. The resistance force may be increased as the angle increases. When the shaking is small, the resistance force may be increased to increase the effect of suppressing the shaking, and when the shaking is large, the resistance force may be decreased to suppress the generation of a force that changes the attitude of the aircraft. It may be changed using a threshold value. The resistance force may be increased when the angle of swing of link Y is large.

[0111] The resistance force may be changed according to the speed of change in the amount of rotation. When the speed of change is large, the resistance force may be decreased so that the attitude of the flying object or the like does not change in response to a sudden change. Alternatively, the resistance force may be increased. In this case, it is expected that the force that the flying object tries to maintain its attitude will suppress the shaking. The resistance force may be changed according to the attitude of the flying object or the like. When the inclination of the flying object is large, the resistance force may be decreased. The resistance force may be increased or decreased according to the difference between the target attitude and the current attitude of the flying object. The resistance force may be changed according to the difference between the target attitude and the current attitude of the rotating object. For example, the resistance force may be increased when the difference is large, and decreased when the difference is small. The reverse is also possible. The resistance force may be changed according to the magnitude of the external force that rotates the rotation mechanism. A means for measuring the external force that rotates at least one of the axes may be provided, and the resistance force may be changed according to the magnitude of the external force. For example, the resistance force is decreased when the external force is large, and increased when the external force is small. The resistance force is decreased in response to large shaking to prevent the attitude of the flying object from collapsing. Here, the magnitude of the resistance force in response to the magnitude of the external force may be reversed. The resistance force may be increased in response to large shaking to suppress the shaking.

[0112] The resistance force may be changed according to the time over which the amount of rotation of the rotation mechanism changes. For example, if the link Y or the like is swinging and the amount of rotation is continuously changing, the resistance force may be increased to suppress the swing. For example, the resistance force may be increased if the swinging time is long.

[0113] The means for preventing rotation may be a combination of the features described above. Other controls may also be added to suppress the shaking and vibration of the rotating body. For example, in a case where the resistance force is increased when the external force is large, the resistance force may be decreased when the external force exceeds a predetermined threshold. This may also be applied to the control of the resistance force against other quantities such as the amount of rotation and the attitude.

[0114] When the rotation mechanism is applied to a multi-rotor drone, the arm that connects the main body to the rotor is often the easiest to connect.

[0115] In the case where the rotation mechanism is rotated passively, by providing a means capable of calculating the amount of rotation of any of the joints of each axis, it is possible to calculate the self-position of the aircraft 100 relative to something connected to the link Y6 or the link Y, such as the payload 101. As in the example of FIG. 8, this can be used to control the aircraft when the payload 101 is connected by a wire or the like, or when the aircraft is tethered. An example of the means capable of calculating the amount of rotation is a rotary encoder or a tachometer.

[0116] The rotation mechanism of the present invention is not limited to the application examples shown so far, and can also be used for other rotations. For example, it can be used for rotation to change the direction of a tire when steering. By setting the rotation reference to the tire and the rotating body to the vehicle body side, it is possible to set the tire rotation axis related to steering inside the tire, that is, on the ridge of the tire, without providing a member or structure that serves as the steering rotation axis inside the tire. Here, link X may be considered as the tire and link Y as the vehicle body. Also, they may be assigned in reverse.

[0117] The above-described embodiment is an example for facilitating understanding of the present invention, and is not intended to limit the present invention. The present invention can be modified or improved without departing from the spirit of the present invention, and it goes without saying that the present invention includes equivalents. In addition, the present invention may be considered to be implemented as a device having the rotation mechanism of the present invention.

[0118] The function of one component in the present embodiment may be distributed among multiple components, or the functions of multiple components may be integrated into one component. Also, at least a part of the configuration of the present embodiment may be replaced with a configuration having a similar function. [Industrial Applicability]

[0119] In cases where it is applied to tethered or suspended flights, it is possible to suppress the attitude change of the aircraft caused by the swinging of the string or payload, thereby reducing the risk of crashing. Since it is possible to suppress the attitude change of the aircraft in response to pulling, it is expected to reduce the risk of crashing and improve the possibility of recovering the aircraft. [Explanation of symbols]

[0120] 0 Rotation center O, 1 Link X, 2 Link A, 3 Link B, 4 Link C, 6 Link Y, 10 Joint XA, 11 Joint XC, 12 Joint AB, 13 Joint BC, 15 Joint BY, 30 Arm, 31 Actuator, 32 Drive link, 100 Aircraft, 101 Payload, 103 Hollow rotating shaft, 104 Rotation center of hollow rotating shaft, 105 Redundant link 1, 106 Redundant joint 1, 107 Redundant joint 2, 108 Redundant link A, 109 Redundant joint XA, 110 Redundant joint AB, 111 Aircraft arm, 112 Link connection part, 601 Bearing or motor, 602 Connection member to rotation reference, 701 Link X, 702 Link Au, 703 Link Ad, 704 Link B, 705 Link Cu, 706 Link Cd, 708 Link E, 709 Link Y, 710 Joint XAuz, 711 Joint XCuz, 712 Joint XEz, 713 Joint AuBz, 714 Joint BCuz, 715 Joint BEz, 716 Joint AdBz, 717 Joint BCdz, 719 Joint BYz, 722 Center of rotation Oz, 810 Joint XAux, 811 Joint XCux, 812 Joint XEx, 813 Joint AuBx, 814 Joint BCux, 815 Joint BEx, 816 Joint AdBx, 817 Joint BCdx, 819 Joint BYx, 822 Center of rotation Ox, 1500 Counterweight, 1502 Rotation axis, 1700 Connection, 1701 Screw, 1810 String, wire, etc., 1811 Connection point, payout point, 2200 Center of rotation or center of gravity of flying object, 2301 Link 1, 2302 Rotation axis 1, 2303 Link 2, 2304 Rotation axis 2, 2305 Joint, 2801 Link, 2802 Link, 2803 Link, 2810 Joint, 2811 Common rotation axis, 2812 Rotation axis, 2820 Joint, 2821 Common rotation axis, 2822 Rotation axis, 2830 Common joint, 2831 Common rotation axis, 2900 Points to explain examples

Claims

[Claim 1] Link X and Link A are connected by joint XA. Link A and link B are connected at joint AB, Link B and link Y are connected at joint BY, Link C is connected to joint XC on link X and joint BC on link B, A rotation reference is connected to link X, or link X is a rotation reference, A rotating mechanism in which a rotating body is connected to link Y or link Y is the rotating body.

Images