A floating mobile object, attitude control and swarm control of this mobile object.

Abstract

The present invention provides a mobile body that is to float in a liquid or a gas. The present invention also performs posture control of the mobile body and performs group control of a plurality of the mobile bodies. The present invention is a mobile body 100 that moves while floating in a liquid or a gas. The mobile body comprises: an axially symmetrical rotary shell 101 that is watertight when in a liquid and airtight when in a gas; and a rotation control device 200 that is housed in the rotary shell. The rotation control device includes a first rotary shaft 212 of the rotary shell that extends in an axial direction that runs along the axis of symmetry, a second rotary shaft 262 that extends along the same axial direction as the first rotary shaft and can rotate free of the first rotary shaft, a first drive part 210 that makes the first rotary shaft rotate, and a second drive part 260 that makes the second rotary shaft rotate. The rotary shell and the rotation control device are rotatably held by the first rotary shaft, and a disk 270 is rotatably held so as to be centered on the second rotary shaft such that an outer diameter part of the disk does not contact the rotary shell.

Description

[Technical field]

[0001] The present invention relates to a moving body that floats in liquid or gas, and further to attitude control of this moving body and group control of a plurality of moving bodies. [Background technology]

[0002] Since a wide range of applications are expected for moving bodies that float and move in liquid or gas, various technologies have been proposed. For example, floating and moving technologies related to submarines, deep-sea exploration vehicles, balloons, and airships are examples of such floating and moving technologies. To obtain power for moving these moving bodies, it is common to have moving parts such as propellers installed on the outside. In this configuration, friction and wear occur between the moving parts and stationary parts such as bearings and seals that come into contact with them, and this friction and wear may cause deterioration of the sealing and generation of wear powder. Furthermore, deterioration of the sealing may affect the moving body due to the external environment, and generation of wear powder may affect the external environment in reverse.

[0003] The characteristic of being unaffected by or not affecting the external environment of the moving body may further expand the range of uses of floating moving bodies. Technologies for moving bodies with sealed outer shells have been proposed as running devices for robots that work in small spaces, robots that work in clean rooms or underwater where high safety and airtightness requirements are required, and highly mobile personal robots that can coexist with people in the home (see Patent Documents 1 and 2).

[0004] On the other hand, as a means for controlling the attitude and orbit of a moving body, for example in the case of an artificial satellite, four control moment gyros (CMG) are arranged for satellite attitude control, and an attitude control torque is output from the gimbal angular velocity, and the magnitude of the torque output from the CMG is controlled so as to become smaller as the singular point is approached (see Patent Document 3).

[0005] As a way to utilize mobile objects, a swarm robot system has been proposed in which a large number of robots gather and operate as a group. By utilizing the characteristics of both a group and individuals, swarm robot systems are expected to be used in many applications, such as transporting goods and monitoring construction sites (see Patent Document 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 07-285475 [Patent Document 2] Utility model registration No. 3116275 [Patent Document 3] JP 2009-298345 A [Patent Document 4] Re-tabled publication No. 2017-212987 Summary of the Invention [Problem to be solved by the invention]

[0007] However, the floating mobile body technology disclosed in Patent Document 1 involves arranging a power source outside the mixing vessel and magnetically levitating and rotating the mixing blades in the vessel using a bulk superconductor, and although this produces the expected effects, there is a possibility that the materials and equipment will be complicated, and autonomous movement is difficult.

[0008] In addition, the technology of a moving body with a sealed outer shell disclosed in Patent Document 2 obtains propulsive force by utilizing the movement of the center of gravity and oscillation of the moving body itself by providing a moving body independent of the outer shell inside a sealed container, and therefore cannot be said to be efficient for floating movement in liquid or gas.

[0009] On the other hand, for floating mobile bodies in liquid or gas, group control of multiple floating mobile bodies is suitable as a means of performing attitude control and orbit control as well as achieving multi-purpose missions, and it is expected that the application of the technologies disclosed in Patent Documents 3 and 4 to floating mobile bodies will broaden the range of uses.

[0010] The present invention has been made in consideration of the above-mentioned background and has an object to provide a moving body that floats in liquid or gas, and further to enable attitude control of this moving body and group control of multiple moving bodies. [Means for solving the problem]

[0011] The present invention is a moving body that moves while floating in a liquid or gas. One aspect of the present invention includes a rotating shell having an axisymmetric shape that is watertight in a liquid or airtight in a gas, and a rotation control device stored in the rotating shell, the rotation control device having a first rotation axis of the rotating shell extending in an axial direction passing through an axis of symmetry, a second rotation axis extending coaxially with the first rotation axis and rotatable relative to the first rotation axis, a first drive unit that rotates the first rotation axis, and a second drive unit that rotates the second rotation axis, the rotating shell and the rotation control device are axially supported by the first rotation axis, and further includes a disk axially supported around the second rotation axis so that an outer diameter portion does not contact the rotating shell.

[0012] The above-mentioned configuration was created by focusing on the moment of inertia, which is an indicator of the difficulty of turning. For example, if we consider a motorboat equipped with a single screw, the moment of inertia of the hull is extremely large compared to the screw. And since water resistance is also applied to turn the hull, the difficulty of turning the hull increases even more. Therefore, even if the screw is rotated, the hull does not rotate, and the propulsion force is obtained by the blades of the screw paddling the water.

[0013] This configuration applies this concept, consisting of a rotating shell which serves as a watertight and airtight container, and a rotation control device which is connected to this rotating shell only by a rotating shaft. Due to the difference in the moment of inertia (difficulty in rotation) and angular kinetic energy between the two, the rotating shell (outer shell) rotates at a higher speed in absolute coordinates than the rotation control device (inside).

[0014] With this configuration, the only part of the floating mobile body exposed to the outside environment is the rotating shell (outer shell), and the shell can easily be made environmentally resistant simply by selecting the material for the shell. The rotation of the rotating shell creates friction with the liquid or gas that constitutes the outside environment, generating propulsive force and stirring force.

[0015] However, when the resistance of the external environment against the rotating shell is large, the difference in the moment of inertia between the rotating shell (outer shell) and the rotation control device (inner part) alone may cause the rotation control device to rotate together with the rotating shell, and it may not be possible to achieve the desired rotation speed. For this reason, this configuration further includes a disk mounted around the second rotation axis so that the outer diameter part does not come into contact with the rotating shell. The rotation of this disk generates kinetic energy due to rotation. By imparting kinetic energy to the rotation control device in this way, the amount that cannot be offset by the difference in the moment of inertia alone can be compensated for by the rotation of the disk (so-called flywheel effect).

[0016] Furthermore, with this configuration, friction and wear do not occur between the moving parts and the stationary parts such as bearings and seals that come into contact with them, so it is possible to eliminate the risk of deterioration of the seal due to friction and wear, and the generation of wear powder. In other words, it is possible to eliminate the adverse effects of the external environment on the moving body due to deterioration of the seal, and the adverse effects on the external environment due to the generation of wear powder.

[0017] In the movable body of the above embodiment, the disk can be configured to rotate so as to suppress rotation of the rotation control device depending on the rotation speed of the first rotating shaft and the resistance force between the rotating shell and the liquid or gas when rotating.

[0018] According to the above-mentioned configuration, it is possible to achieve the objective of not rotating the rotation control device without the need for a complicated means of determining the rotation speed of the flywheel by measuring the specifications and motion state of the structure, the characteristics related to the friction between the surrounding fluid and the rotating shell, etc. In other words, by measuring the rotation direction of the rotation control device, the rotation direction of the disk is reversed and rotated, and by performing feedback control in which this operation is repeated until the rotation control device is almost stationary, the rotating shell can be rotated at the desired rotation speed.

[0019] In the moving body of the above aspect, the rotation control device can be configured to include a control unit that controls the rotation of the first rotation shaft, a receiving unit that receives a signal to the control unit, and a power supply unit that supplies power to the control unit and the receiving unit, and to rotate the first rotation shaft based on the signal transmitted from outside the rotating shell.

[0020] According to this configuration, the rotation of the floating mobile body can be controlled by wireless communication from the outside. Then, by controlling the rotation drive, the floating mobile body can be moved, its position can be maintained, and other movements can be realized. The power supply unit can be equipped with a normal secondary battery or the like, or a solar cell can be arranged on the surface of the rotating shell, or on the outer surface of the rotation control device when the rotating shell is transparent, to supply power. Furthermore, a part of the rotating shell can be made a conductor, and power can be supplied directly from this conductor, and the power can be conducted from the rotating shell to the power supply unit in the rotation control device via a slip ring.

[0021] In the moving body of the above aspect, the rotation control device can be configured to include a measuring device that measures the acceleration, geomagnetism, temperature, humidity, and air pressure inside the rotating shell of the moving body, and a transmitting unit that transmits data acquired by the measuring device to outside the rotating shell.

[0022] According to this configuration, the following states of the floating mobile object can be confirmed. That is, by measuring the acceleration of the mobile object, the rotation speed can be calculated from the analysis result, and the position in liquid or gas can be calculated as the calculation result by integrating the initial position coordinate and the acceleration. By measuring the geomagnetic field, the self-position can be estimated. By measuring the temperature inside the rotating shell, the change in the ambient temperature can be obtained, although there is a slight time lag. By measuring the humidity and air pressure inside the rotating shell, the watertight and airtight state of the floating mobile object can be obtained. These measured physical quantities can be used for the amount of feedback for control, the transmission of alert information, the status of the external environment, etc. Note that the data transmission and reception can be done by radio waves or visible light communication, and is not particularly limited.

[0023] In the moving body of the above-mentioned aspect, the rotation control device can be configured to include a plurality of control moment gyros (CMGs) and to control the drive of the plurality of CMGs so that the moving body assumes a specified attitude based on a signal indicating the attitude of the moving body transmitted from outside the rotating shell and the measurement results of the measuring device.

[0024] A control moment gyro (CMG) is an actuator that controls attitude by torque (gyro effect) obtained by changing the direction of rotation of a wheel by rotating a gimbal axis, and is often used for attitude control of artificial satellites. Compared to other torque generating devices, CMGs have a large output torque and enable high-speed attitude control, and by installing multiple CMGs and controlling the generated torque, it is possible to change and stabilize the attitude.

[0025] According to the above configuration, by mounting multiple CMGs and controlling their attitude, the moving direction of the floating moving body can be controlled. Also, by changing the attitude, the direction of the propulsive force obtained by the rotation of the rotating shell can be changed, so the traveling direction of the moving body can be controlled. Since this CMG acts similarly to a rotating disk (flywheel), the attitude and rotation of the moving body as a whole may be controlled by considering the rotation control of the disk together with the operation of the CMG, as necessary.

[0026] In the moving body of the above aspect, each of the CMGs may be configured to include a wheel controller that rotates a wheel about a wheel rotation axis, a gimbal controller that supports the wheel and rotates a gimbal mechanism about a gimbal rotation axis that is perpendicular to the wheel rotation axis, a linear approximation unit that calculates a solution to a Riccati equation based on a required gimbal angular velocity and sets in advance a feedback function that linearly approximates the calculated solution, a gain calculation unit that calculates a gain of the gimbal controller using the feedback function set by the linear approximation unit at a singularity or in the vicinity of a singularity where the CMG is no longer able to output an attitude control torque in a specific direction, and a control torque generation unit that generates the attitude control torque based on the rotational torque of the gimbal motor based on the gain calculated by the gain calculation unit and the rotational torque of the wheel motor.

[0027] According to the above configuration, in attitude control using the CMGs, it is possible to solve the singularity problem in which the torques generated by each CMG cancel each other out. That is, the linear approximation unit calculates a solution to the Riccati equation based on the required gimbal angular velocity, and sets in advance a feedback function that linearly approximates the calculated solution. At a singularity or near a singularity where the CMGs are no longer able to output attitude control torque in a specific direction, the gain calculation unit calculates a gain for the gimbal controller using the feedback function set by the linear approximation unit. The control torque generation unit generates attitude control torque based on the rotational torque of the gimbal motor based on the gain calculated by the gain calculation unit and the rotational torque of the wheel motor, so that gimbal tracking can be improved even in a singularity state. With this configuration, it is possible to realize attitude control with a low calculation load.

[0028] In the moving body of the above aspect, the moving body is equipped with a group control measurement unit that acquires information on the relative positions and speeds of the moving bodies and of objects present in an area in which the moving bodies can move, a group control communication unit that exchanges the information between the moving bodies, and a group control unit that issues commands to control the moving direction and speed of the moving body based on the information, and the group control unit sets in advance a virtual object temperature for the object and a virtual initial moving body temperature that is lower than the virtual object temperature for the moving body, and calculates a temperature difference between the virtual object temperature and the previous moving body temperature. A virtual moving body temperature changed by virtual heat transfer is calculated from the virtual initial moving body temperature and the distance between the moving body and the object, and a mathematical model of thermodynamics is used to calculate a virtual attractive and repulsive force that keeps the distance between the moving bodies constant from the distance between the moving bodies, and a virtual repulsive force acting between the object and the moving body from the virtual moving body temperature, and the rotation speed of the CMG and the rotating shell is controlled according to the movement direction and speed of the moving body obtained by the sum of the attractive and repulsive forces.

[0029] According to the above configuration, by applying the thermodynamic concept of phase transition to group control of moving objects, collective movement of moving objects can be realized with a low computational load, and when an obstacle is present, only those moving objects affected by the obstacle can be avoided, thereby allowing the appropriate parts of centralized control and decentralized control to be appropriately and independently selected. Effect of the Invention

[0030] The present invention provides a moving body that floats in liquid or gas, and further makes it possible to realize attitude control of this moving body and group control of a plurality of moving bodies. [Brief description of the drawings]

[0031] [Figure 1] 1 is an overall explanatory diagram showing a side cross section of a floating moving body according to a first embodiment of the present invention; [Diagram 2] 3A to 3C are explanatory views showing the operation of a floating moving object in a container according to the first embodiment of the present invention. [Diagram 3] FIG. 2 is an explanatory diagram of the operating principle of the present invention. [Figure 4] 10 is an overall explanatory diagram showing a side cross section of a floating moving body according to a second embodiment of the present invention; FIG. [Diagram 5] FIG. 11 is a diagram showing an attitude control device according to a second embodiment of the present invention, illustrating an arrangement of four CMGs. [Figure 6] FIG. 11 is a diagram showing an attitude control device according to a second embodiment of the present invention, illustrating the arrangement of two CMGs. [Figure 7] FIG. 6 is an explanatory diagram of a CMG mechanism of an attitude control device according to a second embodiment of the present invention. [Figure 8] FIG. 6 is a block diagram showing a configuration of an attitude control device according to a second embodiment of the present invention. [Figure 9] FIG. 11 is a block diagram showing a case where, instead of finding a solution to a Riccati equation, a solution is linearly approximated according to a second embodiment of the present invention. [Figure 10] 11 is an example of a moving mechanism according to a second embodiment of the present invention. [Figure 11] FIG. 11 is an overall explanatory diagram showing a side cross section of a floating moving body according to a third embodiment of the present invention. [Figure 12] FIG. 13 is an explanatory diagram showing the state of a group of moving objects according to a fourth embodiment of the present invention. [Figure 13] FIG. 13 is an explanatory diagram illustrating an example of a thermodynamic mathematical model according to a fourth embodiment of the present invention. [Figure 14] FIG. 13 is an explanatory diagram showing the movement state of a group of moving objects in an example of collective movement control of a group of moving objects according to a fourth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] Hereinafter, preferred embodiments of the present invention relating to a moving body floating in liquid or gas will be described with reference to the drawings. In the following description, configurations with the same reference numerals in different drawings are considered to be similar, and the description thereof may be omitted.

[0033] One embodiment of the present invention, a movable body that moves while floating in liquid or gas, comprises a rotating shell of an axially symmetrical shape that is watertight in liquid or airtight in gas, and a rotation control device stored within the rotating shell, wherein the rotation control device has a first rotation axis of the rotating shell extending in an axial direction passing through the axis of symmetry, a second rotation axis extending coaxially with the first rotation axis and rotatably relative to the first rotation axis, a first drive unit that rotates the first rotation axis, and a second drive unit that rotates the second rotation axis, and the rotating shell and the rotation control device are axially mounted by the first rotation axis, and the rotating shell and the rotation control device further comprise a disk axially mounted so that the second rotation axis is at the center so that the outer diameter portion does not come into contact with the rotating shell, and the specific embodiment may be any one of these.

[0034] (Explanation of Overall Configuration of First Embodiment) First, a first embodiment of the present invention will be described with reference to Figs. 1 and 2. Fig. 1 is an overall explanatory diagram showing a side cross section of a floating moving body according to the first embodiment of the present invention. Fig. 2 is an explanatory diagram showing the operation of the floating moving body in a container according to the first embodiment of the present invention. Note that in the following description, a case where the moving body is disposed in a container filled with liquid will be described, but it goes without saying that the moving body itself is not limited to being used in a container, and can also be applied in the sea or in the air.

[0035] 1 and 2, this embodiment is a moving body 100 that moves while floating in a liquid 6 in a container 5. The moving body 100 includes a watertight cylindrical rotating shell 101 and a rotation control device 200 stored in the rotating shell 101. The rotation control device 200 includes a first rotating shaft 212 extending in the axial direction of the cylindrical rotating shell 101, a first driving unit 210 that rotates the first rotating shaft 212, a second rotating shaft 262 that extends coaxially with the first rotating shaft 212 and is rotatable relative to the first rotating shaft 212, and a second driving unit 260 that rotates the second rotating shaft 262. The rotating shell 101 and the rotation control device 200 are axially supported by the first rotating shaft 212.

[0036] In FIG. 1, the first rotating shaft 212 and the second rotating shaft 262 are arranged vertically apart, however, it is also possible to apply a coaxial counter-rotating brushless motor used in drones, for example, and arrange a cylindrical second rotating shaft 262 around the first rotating shaft 212, thereby making the space more compact.

[0037] The rotating shell 101 is a sealed container that is watertight when in liquid or airtight when in gas. A suitable material that is not affected by the external environment can be used for the rotating shell 101, and may be metal-based or resin-based. For example, in an environment of high external pressure, a multiple / multi-layer structure can be used with a resin outer shell that covers the framework of a metal structure to prevent buckling. Furthermore, a material that easily transmits radio waves or light between the inside and outside of the rotating shell 101 can be selected for communication with the outside or power transmission.

[0038] The size of the rotating shell 101 is set in order to adjust the amount of buoyancy and moment of inertia of the moving body 1 according to the environment in which it is used, and a working gas according to the external environment can be sealed inside the rotating shell 101.

[0039] A plurality of blades 110 are provided on the side of the cylinder of the rotating shell 101. The blades 110 can capture the surrounding fluid by rotating the rotating shell 101, and generate a pressure difference between the front and rear of the blades 110. In addition, by tilting the blades 110 in the axial direction, a propulsive force can be obtained in the axial direction upward or downward. The position of the blades 110 is not limited to being arranged on the side of the cylinder, and they can also be arranged on the upper surface, lower surface, etc. In addition, the blades 110 can be provided with an actuator to make them movable wings that can be tilted or folded. As this actuator, for example, a shape memory alloy can be arranged inside the blades 110 and driven by a command from the rotation control device 200. Note that, although FIG. 1 shows the blades 110 protruding from the side of the rotating shell 101, the present invention is not limited to this form, and for example, impellers that discharge fluid in the radial flow direction used in turbines and pumps, or that discharge fluid in the axial direction in a similar manner, may be appropriately provided on the top and bottom of the moving body 100.

[0040] In the rotation control device 200, the first driving unit 210, the control unit 220, the transmitting / receiving unit 230, the measuring unit 240, the power supply unit 250, the second driving unit 260, and the disk 270 are mounted inside a frame 201. Furthermore, a sensor 242 is disposed on the side surface of the frame 201.

[0041] The first driving unit 210 can be an electric motor, and includes a first rotating shaft 212 that serves as a rotor, a bearing 215 that supports the first rotating shaft 212, and a stator 216. The first driving unit 210 drives and rotates the first rotating shaft 212 and the rotating shell 101 that is journalled on the first rotating shaft 212 by supplying electric power.

[0042] The second driving unit 260 can be an electric motor, and includes a second rotating shaft 262 serving as a rotor, a bearing 265 supporting the second rotating shaft 262, and a stator 266. The second driving unit 260 drives and rotates the second rotating shaft 262 and a disk 270 journaled on the second rotating shaft 262 by supplying electric power.

[0043] The control unit 220 commands and executes the supply of power to control the rotation of the first drive unit 210 and the second drive unit 260. The control unit 220 also drives the blades 110 when the blades are movable. Furthermore, a balance weight (not shown) or the like may be movably arranged on the frame 201, and the attitude of the moving body 100 may be stabilized by manipulating the position of the balance weight or the like.

[0044] The control unit 220 can be configured to transmit a signal to the second drive unit 260 to suppress rotation of the rotation control device 220 and rotate the disk 270 in response to a command for the rotation speed of the first rotating shaft 212 and the resistance force between the rotating shell 101 and the surrounding liquid or gas when it rotates.

[0045] With this configuration, it is not necessary to take a complicated means of determining the rotation speed of the disk 270 that exerts a flywheel effect by measuring the specifications and motion state of the structure, and the characteristics related to the friction between the surrounding fluid and the rotating shell, and it is possible to control the rotation control device 220 so that it does not rotate. More specifically, the rotation direction of the disk 270 is rotated in the opposite direction to that of the rotation control device 220 by measuring the rotation direction of the rotation control device 220 by the sensor 242. Then, the control unit 220 performs feedback control to repeat this operation until the rotation control device 220 is almost stationary, so that the rotating shell 101 can be rotated at a desired rotation speed to rotate the blades and generate the required propulsive force even if there is resistance between the rotating shell 101 and the surrounding liquid or gas.

[0046] The control unit 220 is composed of a microcomputer and has a processor CPU that performs calculations, a ROM that stores control programs and lists, tables, and maps of various data, and a RAM that temporarily stores the results of calculations by the CPU. The control unit 220 is equipped with a non-volatile memory, and data necessary for control in the next driving cycle is saved in this non-volatile memory. The non-volatile memory can be composed of an EEPROM, which is a rewritable ROM, or a RAM with a backup function that supplies a holding current to retain memory even when the power is turned off.

[0047] The transceiver unit 230 receives commands such as start, stop, and speed of rotation, movement and posture of the moving body 100, etc., transmitted from the outside, as signals, and transmits the power supply status of the first driving unit 210 and the second driving unit 260, and other measurement data by the sensor 242, etc. The transmission method and reception method are not particularly limited, and radio waves, visible light, infrared light, ultrasonic waves, etc. can be applied.

[0048] The transmitting / receiving unit 230 may also be a receiver of power from the power transmission device 10 shown in Fig. 2. The method of wireless power transmission is not particularly limited, and may be appropriately selected from non-radiative types such as magnetic coupling, electrolytic coupling, and evanescent wave, and radiative types such as laser, microwave, and ultrasonic. In this embodiment, the power transmission device 10 is disposed in the container 5, but the power transmission device 10 may also be disposed in a fixed facility or another mobile body, and the mobile body 100 may transmit power by approaching the fixed facility or another mobile body.

[0049] The measurement unit 240 transmits data acquired by a plurality of sensors 242 that measure the acceleration of the moving body 100, geomagnetism, temperature, humidity, air pressure, etc. inside the rotating shell 101 to the outside of the rotating shell 101 via the receiver / transmitter 230. As described above, the acceleration of the moving body can be used to calculate the number of rotations as an analysis result, and the position in liquid or gas can be calculated as a calculation result by integrating the initial position coordinate and acceleration. The geomagnetism can estimate the self-position. The temperature inside the rotating shell can obtain the change in the ambient temperature, although there is a slight time lag. The humidity and air pressure inside the rotating shell can obtain the watertight and airtight state of the floating moving body. These physical quantities can be used for the amount of feedback for control, the transmission of alert information, the state of the external environment, etc.

[0050] The power supply unit 250 may be a secondary battery (storage battery, rechargeable battery) such as a lead storage battery, a nickel-cadmium storage battery, a metal lithium battery, a lithium ion secondary battery, a lithium ion polymer secondary battery, or a sodium ion battery, or may be a fuel cell or a solar cell, and is not particularly limited. It may also be configured to directly supply power by wireless power transmission from an external source.

[0051] In this embodiment, the container 5 is filled with the liquid 6, but it goes without saying that the present invention can also be applied to situations where there is no container 5, such as in water or in gas.

[0052] Referring to FIG. 2, the moving body 100 floats in a container 5 filled with a liquid 6, and by operating a drive unit 216 in a rotation control device 200, the moving body 100 rotates R about an axis Z as the rotation axis.

[0053] In manufacturing the moving body 100, the rotation control device 200 is enclosed in the rotating shell 101, but for example, the upper part of the rotating shell 101 in Fig. 1 may be made into a lid shape so that it can be removed as needed. Also, a cap-shaped gas-filling part may be provided in a part of the rotating shell 101, and there is no particular limitation.

[0054] (Explanation of the operating principle) The rotation R will be described below mainly with reference to FIG. 3. FIG. 3 is an explanatory diagram of the operating principle of the present invention. Referring to FIG. 3, for the sake of simplicity, (a) considers the rotation control device 200 as a cylinder, and (b) considers the rotating shell 100 as a cylinder. In FIG. 3 and the following formulas, the respective symbols are I: moment of inertia, Z: axis of rotation, a: outer diameter, M: mass, F: resistance force due to viscosity, w: angular velocity, K: kinetic energy, f: energy increase in the rotating shell 101 caused by F, and the subscripts 1: rotation control device 200, 2: rotating shell 101, and z: axis of rotation.

[0055] Here, the moment of inertia around the Z axis of the rotation control device 200 (subscript 1) is I 1Z =1 / 2×M1×a1 2 The kinetic energy of the rotation control device 200 (subscript 1) around the Z axis is expressed as follows: K1=1 / 2×I 1Z ×w1 2 It is expressed as:

[0056] Next, the moment of inertia around the Z axis of the shell of revolution 101 (subscript 2) is I 2Z =M2×a2 2 The kinetic energy of the shell of revolution 101 (subscript 2) around the Z axis is expressed as: K2=1 / 2×I 2Z ×w2 2 It is expressed as:

[0057] Here, I 1Z >> I 2Z So that the relationship is 1Z , I 2Z When these are set, K1>>K2 holds. This relationship means that the rotating shell 101 (subscript 2) rotates relatively faster around the Z axis of the stationary coordinate system than the rotation control device 200 (subscript 1).

[0058] Furthermore, when the floating mobile body 1 is rotating in a fluid (gas or liquid), resistance occurs due to the viscosity of the fluid against the outer surface of the cylinder or sphere of the shell of revolution 101 (subscript 2) or the attached blades.

[0059] The energy generated by this resistance acts to increase the apparent kinetic energy of the shell of revolution 101 (subscript 2). In this case, the required rotation of the outer shell can be obtained by increasing M1, for example, by mounting a weight or by suppressing the rotation of the target object 1 from the outside so that the following inequality is satisfied: K1>> K2+f(F)

[0060] As described above, the rotation control device 200 (the internal drive unit) and the rotating shell 101, which rotate relative to each other, have different rotation speeds and may also have different rotation directions in the absolute coordinate system. However, the rotating shell 101 can rotate the moving body 100 at an angular velocity w3 with a viscous resistance force F applied to it, as shown in Figure 3(c) relative to the absolute coordinate system.

[0061] Here, the factors that determine the "rotation speed" and "rotation direction" are listed again as follows: 1) the resistance between the rotating shell and the surrounding fluid, 2) the driving force of the motor, and 3) the moment of inertia of the rotating shell and the rotation control device around the rotation axis. That is, depending on the environment in which the floating mobile body 100 is used and the required rotation speed, it is possible to deal with the following: attaching a weight to either the rotating shell 101 or the rotation control device 200 to increase the mass, reducing the weight, changing the arrangement of the mounted equipment around the rotation axis, adjusting the attractive and repulsive forces of the opposing magnets arranged in the rotating shell 101 and the rotation control device 200, or changing the shape of the blades.

[0062] Furthermore, in this embodiment, the control unit 220 sends a signal to the second driving unit 260 to suppress the rotation of the rotation control device 220 according to a command for the rotation speed of the first rotating shaft 212 and the resistance force between the rotating shell 101 and the surrounding liquid or gas when it rotates, thereby rotating the disk 270. The kinetic energy K3 around the Z axis generated by the rotation of the disk 270 is expressed by the following formula by rotating the disk 270 in the opposite direction to the rotation control device 220, and the required rotation of the outer shell can be reliably obtained. K1+ K3>> K2+f(F)

[0063] As described above, in this embodiment, by using a different moment of inertia and providing the disk 270 as a flywheel, it is possible to improve the mobility of the floating mobile body 100 in various surrounding environments, and also to improve the accuracy of attitude control and drive control.

[0064] (Explanation of Overall Configuration of Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 4 to 10. FIG. 4 is an overall explanatory view showing a side cross-section of a floating mobile body according to the second embodiment of the present invention. FIG. 5 is an arrangement diagram of four CMGs, which is an attitude control device according to the second embodiment of the present invention. FIG. 6 is an arrangement diagram of two CMGs, which is an attitude control device according to the second embodiment of the present invention. FIG. 7 is an explanatory view of a CMG mechanism part, which is an attitude control device according to the second embodiment of the present invention. FIG. 8 is a block diagram showing the configuration of an attitude control device according to the second embodiment of the present invention. FIG. 9 is a block diagram when the solution of the Riccati equation according to the second embodiment of the present invention is linearly approximated instead of obtaining the solution. FIG. 10 is an example of a moving mechanism according to the second embodiment of the present invention.

[0065] Referring to FIG. 4, in this embodiment, a CMG system 310 of a control moment gyro (hereinafter referred to as "CMG") is additionally mounted in the rotation control device 200 in the configuration of the above-described first embodiment.

[0066] The mobile body 300 according to this embodiment includes a watertight cylindrical rotating shell 101 and a rotation control device 200 stored in the rotating shell 101. The rotation control device 200 includes a common drive unit 320 that rotationally drives the rotating shell 101 and independently rotationally drives a disk 270 from the rotating shell 101, a control module 330 that stores the control unit 220, the transmission / reception unit 230, the measurement unit 240, and the power supply unit 250 of the first embodiment, and stores and mounts the CMG system 310.

[0067] Here, for example, the common drive unit 320 applies a coaxial double-reversal brushless motor, arranges a cylindrical second rotation axis 262 around the first rotation axis 212 in the first embodiment, and aims to compact the space.

[0068] Next, the function of the CMG and the reason for additional mounting in the rotation control device 200 will be described.

[0069] <Explanation of CMG function> A torque generating device is installed to control the attitude and direction of spacecraft and artificial satellites. For example, a reaction wheel or thruster is used as this torque generating device. A thruster cannot operate if it runs out of fuel such as gas. A reaction wheel rotates the artificial satellite body by reacting to the torque of acceleration and deceleration generated by the rotation of a flywheel. However, when the controlled object is a large spacecraft such as a space station, or a space robot that requires high-speed attitude change, a device that generates a large torque is required, and the torque of a reaction wheel may not be enough. Therefore, a CMG is used as an alternative to a reaction wheel.

[0070] A CMG uses a gimbal mechanism to hold a gyro that rotates a flywheel at a constant high speed, and rotates this gimbal around an axis perpendicular to the gyro axis to generate torque from the gyro effect. It has an advantage over a reaction wheel in that it can simultaneously increase the stored angular momentum and generated torque, but as a system for three-axis attitude control of a satellite, controlling a system consisting of three or more CMGs is complicated, and the problem of singularities is unavoidable, which has been an issue.

[0071] In other words, the CMG requires the inverse of a time-varying matrix that contains trigonometric functions, and complex calculations must be performed repeatedly at high speed. A state in which this inverse matrix calculation is not possible is a kinematic singularity of the CMG, in which case all of the torque vectors that can be generated by the CMG device are in two-dimensional space, and torque cannot be generated in the remaining axis direction. For attitude control, such singularities must be avoided.

[0072] In the environment in which this embodiment is applied, since the surrounding environment is gas or liquid, a large resistance occurs compared to a spacecraft or artificial satellite in a vacuum state, and the torque required for attitude direction control becomes large. Therefore, it is preferable to mount a CMG that generates a large torque not only for attitude direction control but also for effectively rotating the above-mentioned rotating shell.

[0073] In this embodiment, in order to solve the singularity problem, in an attitude control device equipped with a plurality of control moment gyros (CMGs), each CMG is configured to include a wheel controller that rotates a wheel about a wheel rotation axis, a gimbal controller that supports the wheel and rotates a gimbal mechanism about a gimbal rotation axis that is perpendicular to the wheel rotation axis, a linear approximation unit that calculates a solution to a Riccati equation based on a required gimbal angular velocity and sets in advance a feedback function that linearly approximates the calculated solution, a gain calculation unit that calculates a gain of the gimbal controller using the feedback function set by the linear approximation unit at a singularity or in the vicinity of a singularity where the CMG cannot output an attitude control torque in a specific direction, and a control torque generation unit that generates the attitude control torque based on the rotational torque of the gimbal motor based on the gain calculated by the gain calculation unit and the rotational torque of the wheel motor.

[0074] According to this configuration, the linear approximation unit calculates a solution to the Riccati equation based on the required gimbal angular velocity, and sets in advance a feedback function that is a linear approximation of the calculated solution. At or near a singular point where the CMG is no longer able to output an attitude control torque in a specific direction, the gain calculation unit calculates a gain for the gimbal controller using the feedback function set by the linear approximation unit. The control torque generation unit generates an attitude control torque based on the rotational torque of the gimbal motor based on the gain calculated by the gain calculation unit and the rotational torque of the wheel motor, thereby making it possible to improve gimbal tracking even in a singular point state. With this configuration, an attitude control device that applies a control method with a low calculation load can be installed.

[0075] <Structural description of the second embodiment> Figures 5 and 6 schematically show a plan view of the CMG system 310 of FIG. 4 as viewed from above. Referring to FIG. 5, the CMG system 310 includes four CMGs 331, 332, 333, and 334 to effectively set the direction of the torque to be generated. FIG. 5 is an example of the CMG arrangement, but it is arranged at the four corners of the base 343 so that torques due to the gyroscopic effect are generated in different directions from each other. When the direction of generating the torque due to the gyroscopic effect is limited or when it can be generated in a direction where there is already a dominant torque (for example, when equipped with a flywheel, other propulsion mechanisms, etc.), the CMG system 310 can be configured such that two CMGs 331 and 332 are arranged vertically as shown in FIG. 6.

[0076] Referring to FIG. 7, the mechanism of the CMG 331 (the same applies to 332, 333, and 334) will be described. The disk-shaped wheel 319 rotates around the wheel rotation axis 327 by the wheel motor 317 around the wheel rotation axis 327.

[0077] A gimbal mechanism 321 is connected to the wheel rotation axis 327. The gimbal mechanism 321 rotates around the gimbal rotation axis 322 by the gimbal motor 315 around the gimbal rotation axis 322 orthogonal to the wheel rotation axis 327. The gimbal motor 315 is fixedly disposed on the rotation control device 200 via a frame or the like as appropriate.

[0078] The CMG 331 generates a gyro torque 325 due to the gyroscopic effect in a direction orthogonal to the wheel rotation axis 327 and the gimbal rotation axis 322 by rotating the wheel 319 rotating at a constant angular velocity around the wheel rotation axis 327 around the gimbal rotation axis 322.

[0079] <Regarding the control of the CMG> Next, the control of the CMG will be described with reference to the block diagrams of Figures 8 and 9. The CMG system 310 includes a control flow related to a required wheel angular velocity dθrw / dt, which is made up of a wheel command 316 and a wheel motor 317, and a control flow related to a required attitude angle θrA, which is made up of a CMG control unit 311, a singular point avoidance unit 312, a gain calculation unit 313, a gimbal controller 314, and a gimbal motor 315.

[0080] A flow of control related to the required wheel angular velocity dθrw / dt will be described with reference to Fig. 8. When the transceiver unit 230 receives an instruction for the attitude of the moving body 300 from the command and control unit 600 outside the moving body 300, or when the moving body 300 autonomously maintains or recovers its own attitude, the control unit 220 issues a control command to the CMG system 310. The CMG system 310 transmits a signal of the required wheel angular velocity dθrw / dt to the wheel command 316, which drives the wheel motor 317 in response to the signal. Then, feedback control is performed until the wheel motor 317 reaches the commanded angular velocity.

[0081] Next, a flow of control related to the required attitude angle θrA will be described. The measurement unit 240 receives the quaternion attitude angular velocity dθqA / dt of the moving body 300 acquired by the sensor 242, calculates the quaternion attitude angle θqA from the quaternion attitude angular velocity dθqA / dt, and transmits the quaternion attitude angle θqA to the CMG system 310. Furthermore, the control unit 220 of the CMG system 310 transmits the required attitude angle θrA to the CMG 310.

[0082] The CMG system 310, which receives the quaternion attitude angle θqA and the required attitude angle θrA, transmits the attitude angle to be controlled to the CMG control unit 311.

[0083] The CMG control unit 311 generates a required torque based on the quaternion attitude angular velocity dθqA / dt and the quaternion attitude angle θqA from the sensor 242 and the measurement unit 240. Quaternion feedback is used as the attitude control law. Note that quaternion (quaternion) is a type of attitude representation method. The quaternion feedback applies a proportional gain and a differential gain to the quaternion and angular velocity that represent the attitude angle error, respectively, to provide the required torque.

[0084] In addition, the CMG control unit 311 suppresses abrupt changes in posture by removing high frequency components using a low pass filter for the required torque generated by quaternion feedback control.

[0085] The singularity avoidance unit 312 calculates a required gimbal angular velocity dθrg / dt using a steering law based on the required torque from the CMG control unit 311, and avoids the above-mentioned singularity specific to the CMG.

[0086] To calculate the torque required by the CMG control unit 311, first, the required gimbal angular velocity dθrg / dt is calculated based on the steering law. The Generalized SR inverse proposed by Bong Wie et al. is used as the steering law. Note that the steering law is one or more control schemes that determine how to rotate each CMG in order to generate the desired total torque (i.e., the commanded torque) without causing singularities or saturation in the CMGs.

[0087] A gain calculation unit 313 calculates a gain of an integral controller included in a gimbal command 314 (hereinafter referred to as a gain) suitable for the required gimbal angular velocity obtained by the singularity avoidance unit 312 .

[0088] The gimbal command 314 uses an integral type optimal servo including an integral type controller. The integral type controller is a type of optimal control and has an integrator. The gimbal command 314 controls the rotation of the gimbal motor 315 with a gain suitable for the required gimbal angular velocity dθrg / dt obtained by the gain calculation unit 313. The operating state of the gimbal motor 315 is acquired by a sensor 342 and fed back to the gimbal command 314.

[0089] When the CMG system 310 is in a singular state (a state in which the system cannot generate torque), null motion and torque error are generated by the steering law described above, and it is necessary to set an optimal gain for the required gimbal angular velocity dθrg / dt at that time.

[0090] 9, in the conventional technology, a weight determination unit 351 included in the gimbal command 314 weights the requested gimbal angular velocity dθrg / dt of, for example, the one having the larger drive amount among the four CMGs 331 to 334, and adjusts the momentum of the CMGs 331 to 334. Specifically, a gain calculation unit 313 determines an optimum gain for the requested gimbal angular velocity dθrg / dt weighted by the weight determination unit 351 by finding a matrix solution of the Riccati equation.

[0091] However, in order to minimize the evaluation function of the integrator 353 included in the gimbal command 314 and obtain the control input, it is necessary to calculate a matrix solution of the Riccati equation. Since this calculation includes calculation of an inverse matrix, the calculation load is very high and the calculation time is long, which has led to issues regarding response time and power consumption.

[0092] This embodiment is based on the finding that when the gain is varied, the solution structure of the matrix solution of the Riccati equation is linear approximation or regression of a quadratic function, enabling control equivalent to optimal control that calculates a solution sequentially.

[0093] For this reason, the control of the CMG system 310 in the first embodiment is configured to include a linear approximation unit 352 that calculates a solution to the Riccati equation based on the required gimbal angular velocity shown in FIG. 9 and sets in advance a feedback function that is a linear approximation of the calculated solution.

[0094] Therefore, since the gain calculation unit 313 calculates the gain using the linearly approximated feedback function of the linear approximation unit 352, it is not necessary to find a solution to the Riccati equation for each control period. As a result, the calculation time with linear approximation can be significantly reduced to about 73.3% compared to the calculation time without linear approximation.

[0095] 10, the moving body 300 equipped with the CMG system 310 can tilt its attitude as shown in (A) and (B), and can generate a tilted swirling flow in the liquid 6 in the container 5 due to the pressure difference between the front and rear of the blades 110 caused by the rotation of the rotating shell 101. In addition, by tilting the blades 110 with respect to the rotation axis of the rotating shell 101, it is also possible to obtain a propulsive force in the upward or downward direction shown by the dashed line.

[0096] (Explanation of Overall Configuration of Third Embodiment) Next, a third embodiment of the present invention will be described with reference to Fig. 11. Fig. 11 is an overall explanatory diagram showing a side cross section of a floating mobile body according to the third embodiment of the present invention. This embodiment is a modified example of the arrangement of the mounted devices, and the functions of the devices are similar to those of the first and second embodiments described above.

[0097] 11, a moving body 500 has a spheroidal shell of revolution 501 housing / mounting a control module 510 housing the control unit 220, the transceiver unit 230, the measurement unit 240, and the power supply unit 250 of the first embodiment, a first drive unit 260, and a CMG system 520. The CMG system 520 may be configured to include a flywheel (disk) in addition to the CMG.

[0098] In this embodiment, a disk / doughnut-shaped rotor 552 is provided near the equator of a spheroidal rotating shell 501, and a stator 551 is disposed in a circular hole in the center of the doughnut shape for this rotor 552. Note that a structure in which bearings are provided on the opposing surfaces of the control module 510 side and the CMG system 520 side may be used so as to prevent rattling when the rotor 552 rotates.

[0099] Furthermore, the outer edge of rotor 552 is joined to rotating shell 501 , so that the rotation of rotor 552 is transmitted to rotating shell 501 .

[0100] The shell of revolution 501 is a sealed container that is watertight when in liquid or airtight when in gas, and has a structure in which two divided ellipsoids are joined at a joint surface 502.

[0101] According to this embodiment, by applying a spheroid to the rotating shell 501, the buckling strength in an environment of high external pressure can be easily improved. In addition, by disposing the rotor 552 and the stator 551 at the equator of the rotating shell, it is possible to easily balance the rotation and also to easily change the attitude. In addition, by forming the joint surface 502 near the equator, maintenance and replacement of the equipment stored and mounted in the rotating shell 501 can be easily performed.

[0102] (Explanation of Overall Configuration of Fourth Embodiment) Next, a fourth embodiment of the present invention will be described with reference to Figs. 12 to 14. Fig. 12 is an explanatory diagram showing the state of a group of moving objects according to the fourth embodiment of the present invention. Fig. 13 is an explanatory diagram showing an example of a thermodynamic mathematical model according to the fourth embodiment of the present invention. Fig. 14 is an explanatory diagram showing the movement status of a group of moving objects in an example of collective movement control of a group of moving objects according to the fourth embodiment of the present invention.

[0103] This embodiment is a group of moving bodies 600 that is group-controlled and consists of at least two or more of the moving bodies 100, 300, 500 described in the first to third embodiments. These moving bodies 100, 300, 500 are equipped with a group control measurement unit that acquires information on the relative positions and speeds of the moving bodies and objects present in the area in which the moving bodies can move, a group control communication unit that exchanges information between the moving bodies, and a group control unit that issues commands to control the moving direction and speed of the moving bodies based on the information. Here, the group control unit is included in the control unit 220 described in the first embodiment, and the acquisition of information related to each moving body is performed by a sensor 242.

[0104] Then, the control unit 220 equipped with the group control unit sets in advance a virtual object temperature for the object and a virtual initial moving body temperature lower than the virtual object temperature for the moving body. Then, the virtual moving body temperature changed by virtual heat transfer is calculated from the virtual object temperature, the virtual initial moving body temperature, and the distance between the moving body and the object, and a mathematical model of thermodynamics is used to calculate a virtual attractive and repulsive force that keeps the distance between the moving bodies constant from the distance between the moving bodies, and a virtual repulsive force acting between the object and the moving body from the virtual moving body temperature. The configuration is such that the CMG and the number of rotations of the rotating shell are controlled according to the moving direction and speed of the moving body obtained by the sum of the attractive and repulsive forces.

[0105] <Explanation about group control> A mathematical model of thermodynamics in the group control of this embodiment will be described with reference to FIGS. The mathematical models applied in this invention are: (1) energy model: attractive and repulsive forces between moving bodies and between obstacles and moving bodies; (2) heat transfer model: virtual exchange of heat between moving bodies and obstacles; and (3) phase transition model: moving bodies and obstacles transition to the same phase based on thermal conditions. These models will be explained in order.

[0106] (Application of energy model) FIG. 12 is an explanatory diagram showing a state of group control according to one embodiment of the present invention, and FIG. 13 is an explanatory diagram showing an example of a thermodynamic mathematical model according to one embodiment of the present invention.

[0107] In the present invention, one moving object is regarded as one molecule, and an energy model, which is a mathematical model of thermodynamics, is applied.

[0108] As shown in the following formula (1), the potential energy of each molecule is the sum of the potential between molecules (Lenard-Jones potential) φ(r) and the thermal energy (Brownian motion) K(T) transmitted from the outside. Here, the potential between molecules φ(r) acts as an attractive or repulsive force, while the thermal energy transmitted from the outside K(T) acts as a repulsive force. Note that this potential forms each molecule into a group and maintains a certain distance between each molecule, so it is described as an attractive or repulsive force.

[0109]

number

[0110] According to thermodynamics, a substance can only maintain a constant state within a certain temperature and pressure range, and can take the form of a solid, liquid, or gas depending on the range. In other words, a change in temperature or pressure causes a substance to undergo phase transitions, such as from solid to liquid and from liquid to gas.

[0111] The solid, liquid, and gas phases each have the same composition and physical properties, and the number of molecules in a given volume decreases in the order of solid, liquid, and gas. The decrease in the number of molecules increases the freedom of molecular motion.

[0112] 12 shows the state of mobile body groups 600, 650 formed by multiple mobile bodies 601, 651, which are likened to molecules in (A) solid phase and (B) liquid phase. In the case of (A) solid phase, the potential (Lenard-Jones potential) φ(r) acting between the mobile bodies 601 (between molecules) shown in equation (1) is large (φ(r)>>K(T)), and it can be described as a state in which the distance between the mobile bodies 601 (between molecules) is constant. This state becomes the mobile body group 600, which is a collection of mobile bodies 601 with rigidity.

[0113] (B) In the case of the liquid phase, both the potential (Lenard-Jones potential) φ(r) acting between the mobile bodies 651 (between molecules) and the thermal energy (Brownian motion) K(T) transmitted from the outside act, and the state can be described as a state in which the distance between the mobile bodies 651 (between molecules) varies. This state becomes a mobile body group 650, which is a collection of mobile bodies 651 with flexibility.

[0114] In this way, this embodiment realizes a collective movement model that is both rigid and flexible by applying the solid-liquid phase transition to the collective movement of moving objects.

[0115] Next, the mathematical model applied in this embodiment will be described with reference to Fig. 13. In Fig. 13, moving bodies 602 and 603 constituting a moving body group 600 and an obstacle (object) 700 are arranged side by side. The distance between the obstacle 700 and the moving body 602 is r il , the distance between the moving objects 602 and 603 is r ij It should be noted that the moving bodies 602 and 603 have cylindrical housings with a diameter σ, and the starting points of the distance are set to the centers of the moving bodies 602 and 603, but the housings are not limited to being cylindrical.

[0116] Here, the obstacle 700 has a temperature T l The moving bodies 602 and 603 are initially set to a temperature T l The temperature of the moving body 602 is set to a lower temperature than T i It states that: For the moving body 602, the following equation (2) is set as an energy model corresponding to the above equation (1). il , the distance r between the moving bodies 602 and 603 ij The sum of the energies can be calculated by simply substituting the observed values ​​of

[0117]

number

[0118] Equation (2) is a mathematical model of thermodynamics that represents the sum of energy. Since the attractive force is the first term on the right-hand side of equation (2) and the repulsive force is the second term, the virtual intermolecular force and virtual thermal energy can be used to control the movement of a single moving body based only on the distance between the moving bodies and the distance between the moving body and an obstacle (object).

[0119] More specifically, the first term on the right hand side of equation (2), which represents an attractive and repulsive force, acts to maintain a constant distance between moving body 602 and nearby moving body 603, and the second term acts to pull moving body 602 away from obstacle 700.

[0120] The attractive force adjustment parameter β, the attractive force maximum value adjustment parameter ε, the repulsive force strength parameter A, and the attractive force strength parameter B can be arbitrarily adjusted according to the environment in which the moving body is placed. For example, in order to prevent the obstacle 700 and the moving body 602 from being close to each other, the temperature T l can be set to a larger value.

[0121] In this way, the energy model of this embodiment allows the relationship between the moving bodies to be easily calculated, and the moving direction and speed of each moving body to be controlled. In other words, the moving bodies themselves can be made to determine whether to move collectively or autonomously, depending on the magnitude of the attractive and repulsive forces.

[0122] (Application of heat transfer model) According to the second law of thermodynamics, when two objects with different temperatures are brought into contact, heat will always flow from the object with the higher temperature to the object with the lower temperature. Referring to FIG. 13, as described above, the obstacle 700 has a temperature T lThe moving bodies 602 and 603 are initially set to a temperature T l A temperature lower than the temperature T is previously set to the moving body 602, and the temperature of the moving body 602 is set to Ti.

[0123] In this embodiment of the present invention, the following formula (3) is set, and virtual heat transfer from the obstacle 700 to the moving bodies 602 and 603 is expressed by formula (3).

[0124]

number

[0125] That is, the temperature T l and the temperature Ti of the moving body 602 is multiplied by a virtual heat transfer coefficient k to create a virtual heat transfer model equivalent to local convection heat transfer.

[0126] According to this heat transfer model, if the temperature difference between the obstacle 700 and the moving body 602 is increased, more heat will be transferred and the temperature of the moving body 602 will rise, so that the moving body 602 will not get too close to the obstacle and will be able to take evasive action, and vice versa.

[0127] (Application of phase transition model) A phase transition refers to the change of a substance from one phase to another. In thermodynamics, a phase is defined as a set of stable states of a system with certain characteristics, and each phase has the same composition and physical properties. For example, the phases in which a substance becomes a gas, liquid, or solid are called the gas phase, liquid phase, and solid phase, and the change of a substance from a gas to a liquid or solid, or vice versa, is called a phase transition.

[0128] In the solid, liquid, and gas phases of a substance, the number of molecules in a given volume decreases in the order of solid, liquid, and gas. As the number of molecules decreases, the freedom of molecular motion increases.

[0129] In a material in a thermal equilibrium state, free energy is minimized according to the Gibbs phase rule. Free energy is the potential φ(r) acting between molecules, which is a virtual intermolecular force with the moving body being a virtual molecule, and is expressed in the first term on the right-hand side of equation (2) and the first term on the right-hand side of equation (1).

[0130] When considering solid and liquid phases, generally, at low temperatures the material becomes solid and is in a stable thermal equilibrium state, and at high temperatures the material becomes liquid and is in a stable thermal equilibrium state. The change from solid to liquid or from liquid to solid is called a phase transition, and the temperature at which the transition occurs is called the phase transition temperature.

[0131] When a solid substance exceeds its phase transition temperature, the temperature derivative of the free energy, which can be regarded as entropy, changes discontinuously, causing a phase transition to a liquid phase, and heat is absorbed. When a liquid substance exceeds its phase transition temperature, the temperature derivative of the free energy, which can be regarded as entropy, changes discontinuously, causing a phase transition to a solid phase, and heat is released.

[0132] In this embodiment of the present invention, this phase transition is expressed by providing a virtual phase transition temperature in advance for a moving body that is a virtual molecule.

[0133] When the amount of heat transfer from the initial obstacle 700 to the moving body 602 is small and the gravitational force between the moving bodies is strong, the multiple moving bodies are firmly bound together. This state represents a solid phase state, and a strong group of moving bodies can be formed in a certain formation.

[0134] On the other hand, when some of the moving bodies that make up the moving body group approach an obstacle and exceed a virtual phase transition temperature due to the exchange of virtual thermal energy, the moving body and the obstacle transition to a single liquid phase. In other words, the moving body and the obstacle are defined as a set of stable states of a system with certain characteristics, which show the same composition and physical properties.

[0135] By becoming one liquid phase, the amount of heat flowing from the obstacle to the moving body increases, raising the virtual temperature of the moving body, and the thermal energy in the second term on the right side of the above equation (2) increases. As the thermal energy increases, the repulsive force acting between the moving body and the obstacle increases, and the moving body avoids the obstacle.

[0136] Furthermore, as the gravitational force between the moving body and surrounding moving bodies becomes relatively weaker, the strong bonds between the multiple moving bodies are dissolved, allowing the moving bodies to maintain their behavior as a group of moving bodies while also adopting flexible and diverse formations that suit the environment.

[0137] Regarding the judgment as to whether the moving body 602 has undergone a phase transition, the free energy and entropy changes can be formulated as described above. In this embodiment, however, the virtual transition temperature is determined by the diameter σ of the moving body and the distance r il The virtual liquid phase is expressed as a ratio of the temperature between the moving body and the object, and the virtual liquid phase is expressed so as to have a temperature distribution shown in the following equation (4).

[0138]

number

[0139] That is, in this embodiment, the distance r il <diameter σ, a phase transition occurs, and the moving body 602 and the obstacle 700 form a virtual liquid phase having a temperature distribution shown in equation (4).

[0140] On the other hand, the distance r il When diameter σ is greater than or equal to the diameter of the obstacle 700, the moving body 602 and the obstacle 700 are in a mutually independent thermal equilibrium state and have no temperature distribution across each other.

[0141] As described above, according to the present embodiment, by applying the thermodynamic concept of phase transition to a group of moving bodies, collective movement of the group of moving bodies can be achieved with a low computational load, and in the event that an obstacle is present, only those moving bodies affected by the obstacle can be avoided, thereby achieving the effect of allowing the appropriate parts of centralized control and decentralized control to be appropriately and independently selected.

[0142] Furthermore, in the above-mentioned embodiment, the virtual transition temperature is determined by the diameter σ and the distance r il The virtual liquid phase has a temperature distribution between the moving body and the object as shown in the above formula (4), so that the virtual phase transition phenomenon can be expressed only by the positional relationship between the moving body and the obstacle, thereby realizing reliable obstacle avoidance of the moving body group.

[0143] 14, there are shown a leader mobile body 901 and a follower mobile body following the leader mobile body 901. A second space 810 surrounded by an obstacle 701 and an obstacle 702 is narrower than the first space 800.

[0144] When some of the follower moving bodies forming the moving body group 900 approach the obstacles 701, 702, a phase transition to a virtual liquid phase is caused in the follower moving body based on the above-mentioned formula (4). When the phase transition occurs and the obstacles 701, 702 and the follower moving body become one virtual liquid phase, the repulsive force for avoiding the obstacles 701, 702 becomes dominant over the attractive force between the moving bodies shown in formula (2) for the follower moving body.

[0145] As a result, the group of moving objects 900 changes to a group of moving objects 920. That is, the group of moving objects changes from a group in which rigidity predominates to a group in which flexibility predominates. The changed group of moving objects 900 moves through the narrow passage between the obstacles 701 and 702 while avoiding the obstacles 701 and 702.

[0146] The group of moving objects 920, with a leader moving object 901 and a number of follower moving objects following it, also moves along a route 815 surrounded by obstacles 702 and 703, avoiding obstacles 702 and 703, and reaches the destination, a third space 820.

[0147] In FIG. 14, the group of moving objects 930 that have reached the third space 820 is a group dominated by flexibility, but it is also possible to assign a number to each moving object and organize them into a group based on this numbering.

[0148] According to the method for controlling collective movement of a group of moving bodies formed by a plurality of the moving bodies of this embodiment, at least one of the moving bodies forming the group of moving bodies is designated as a leader moving body, and the remaining moving bodies are designated as follower moving bodies, and the leader moving body and the follower moving body are capable of communicating with each other, and the leader moving body issues a command to the follower moving body to make the follower moving body follow the leader moving body, and by issuing a command of the destination and route only to the leader moving body, the movement of the group of moving bodies including the follower moving body can be controlled. Therefore, collective movement of the group of moving bodies can be realized with a low calculation load.

[0149] Furthermore, it is possible to provide a group of moving objects and a method for controlling the collective movement of a group of moving objects that realizes a combination of autonomous decentralized control and centralized control according to the environment by applying a mathematical model of thermodynamics to the control.

[0150] As described above, the present invention provides a moving body that floats in liquid or gas, and further enables attitude control of this moving body and group control of a plurality of moving bodies. [Explanation of symbols]

[0151] 5...container 6...Liquid 10. Power transmission device 100, 300, 500, 601, 602, 603, 651, 901... Mobile 101,501... Shell of revolution 110···Feather 200... Rotation control device 201...Frame body 210... First drive unit 212... First rotation axis 215,265···Bearing 216,266,551···Stator 220... Control unit 230... Transmitter / receiver unit 240...Measuring section 242,341,342...Sensor 250...Power supply section 260...Second drive unit 262...Second rotation axis 270 Disc 310,520···CMG system 311···CMG control unit 312...Singularity avoidance part 313 Gain calculation unit 314 Gimbal command 315···Gimbal motor 316···Wheel Command 317···Wheel motor 319···Wheels 320...Common drive unit 321 Gimbal mechanism 322 Gimbal rotation axis 325···Gyro torque 327 Wheel rotation axis 330,510···Control module 331,332,333,334···CMG 351 Weight setting unit 352...Linear approximation part 353...integrator 502...joint surface 552···Rotor 600,650,900,920,930... Mobile group 700,701,702,703...Obstacles 800···1st Space 810...Second Space 815... Route 820...Third Space

Claims

1. A shell of revolution having an axisymmetric shape that is watertight in liquid or airtight in gas; a rotation control device housed within the rotating shell; The rotation control device is a first axis of rotation of the shell of revolution extending in an axial direction through an axis of symmetry; a second rotation shaft extending coaxially with the first rotation shaft and rotatably relative to the first rotation shaft; a first drive unit that rotates the first rotation shaft; A second drive unit that rotates the second rotation shaft, The rotating shell and the rotation control device are journalled by the first rotating shaft, a disk mounted around the second rotation axis so that an outer diameter portion of the disk does not contact the rotation shell; Depending on the rotation speed of the first rotating shaft and the resistance force between the rotating shell and the liquid or gas when the first rotating shaft rotates, A moving body that moves while suspended in liquid or gas, characterized in that the disk is rotated so as to suppress rotation of the rotation control device.

2. The rotation control device is A control unit that controls the rotation of the first rotation shaft; A receiving unit that receives a signal to the control unit; a power supply unit that supplies power to the control unit and the receiving unit, 2. The moving body according to claim 1, wherein the first rotation shaft is rotated based on the signal transmitted from outside the rotating shell.

3. the rotation control device is a measuring device for measuring the acceleration, geomagnetism, temperature, humidity, and air pressure of the moving body; 3. The moving body according to claim 1, further comprising a transmitting unit that transmits data acquired by the measuring device to an outside of the rotating shell.

4. The rotation control device is Equipped with multiple control moment gyros (CMGs), A moving body as described in any one of claims 1 to 3, characterized in that the drive of a plurality of CMGs is controlled so that the moving body is in a commanded attitude based on a signal instructing the attitude of the moving body transmitted from outside the rotating shell and measurement results from a measuring device.

5. Each of the CMGs comprises: a wheel controller for rotating the wheel about a wheel rotation axis; a gimbal controller that supports the wheel and rotates a gimbal mechanism about a gimbal rotation axis that is perpendicular to the wheel rotation axis; a linear approximation unit that calculates a solution to a Riccati equation based on a required gimbal angular velocity and presets a feedback function that is a linear approximation of the calculated solution; a gain calculation unit that calculates a gain of the gimbal controller using the feedback function set by the linear approximation unit at a singular point or near a singular point where the CMG cannot output an attitude control torque in a specific direction; 5. The moving body according to claim 4, further comprising a control torque generation unit that generates the attitude control torque based on a rotational torque of a gimbal motor based on the gain calculated by the gain calculation unit and a rotational torque of a wheel motor.

6. The moving body includes: a group control and measurement unit that acquires information on the relative positions and velocities of the moving bodies and of objects present in an area in which the moving bodies can move; a group control communication unit for exchanging the information between the mobile objects; a group control unit that issues a command to control a moving direction and a speed of the moving object based on the information, The group control unit, A virtual object temperature is set in advance for the object, and a virtual initial moving object temperature, which is lower than the virtual object temperature, is set in advance for the moving object; calculating a virtual moving body temperature that has changed due to a virtual heat transfer from the virtual object temperature, the virtual initial moving body temperature, and a distance between the moving body and the object; Using a mathematical model of thermodynamics, a virtual attractive and repulsive force that keeps the distance between the moving bodies constant is calculated from the distance between the moving bodies, and a virtual repulsive force acting between the object and the moving body is calculated from the virtual moving body temperature; 6. The moving body according to claim 4, wherein the rotation speed of the CMG and the rotating shell is controlled in accordance with a moving direction and a speed of the moving body obtained by the sum of the attractive force and the repulsive force.

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