Actuator mechanism and robot device

Abstract

The present disclosure relates to an actuator mechanism and a robot device which make it possible to achieve driving with high responsiveness. The actuator mechanism according to the present disclosure includes: a plurality of shape memory alloy wires, each of which has one end as a fixed end; and a plurality of fitting mechanisms, which are connected to the other ends of the respective shape memory alloy wires and are detachably fitted to an object to be driven. The fitting mechanism is adhered to the object when the shape memory alloy wire is energized, and is detached from the object when the shape memory alloy wire is not energized. The present disclosure can be applied to, for example, an actuator of a robot.

Description

Actuator Mechanism and Robot Device

[0001] The present disclosure relates to an actuator mechanism and a robot device, and particularly to an actuator mechanism and a robot device that achieve highly responsive driving.

[0002] In recent years, many actuators using shape memory alloys (SMAs: Shape Memory Alloys) have been proposed. For example, Patent Document 1 discloses a shape memory alloy actuator that drives a hand arm for gripping a workpiece so as to be switchable between a non-gripping state when energized and a gripping state when not energized.

[0003] Japanese Patent Application Laid-Open No. 2015-217466

[0004] In order for a wire (shape memory alloy wire) used in a shape memory alloy actuator to generate a high stress, it is effective to increase its diameter. On the other hand, as the diameter of the shape memory alloy wire increases, it takes time for natural cooling when the power is turned off, so the responsiveness is significantly reduced.

[0005] The present disclosure has been made in view of such a situation and realizes highly responsive driving.

[0006] The actuator mechanism of the present disclosure includes a plurality of shape memory alloy wires having one end as a fixed end, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires and detachably fitted to an object to be driven. The fitting mechanism is an actuator mechanism that adheres to the object when the shape memory alloy wire is energized and detaches from the object when the shape memory alloy wire is not energized.

[0007] The robot device of the present disclosure includes a plurality of shape memory alloy wires having one end as a fixed end, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires and detachably fitted to an object to be driven. The fitting mechanism is a robot device having an actuator mechanism that adheres to the object when the shape memory alloy wire is energized and detaches from the object when the shape memory alloy wire is not energized.

[0008] In this disclosure, an actuator mechanism comprises a plurality of shape memory alloy wires, one end of which is a fixed end, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires, which are detachably fitted to an object to be driven, wherein the fitting mechanisms are bonded to the object when the shape memory alloy wires are energized, and detached from the object when the shape memory alloy wires are not energized.

[0009] This is a diagram illustrating the operation of a general actuator mechanism. This is a diagram showing an example of the displacement between the object and the SMA. This is a diagram showing an example configuration of the actuator mechanism of this disclosure. This is a diagram illustrating the operation of the actuator mechanism of this disclosure. This is a diagram showing the displacement between the object and the SMA. This is a flowchart illustrating the flow of the object drive process. This is a diagram illustrating the detailed operation of the fitting mechanism. This is a diagram showing another example of the displacement between the object and the SMA. This is a diagram showing a modified version of the actuator mechanism. This is a diagram showing an example configuration of a robot device.

[0010] The following describes the forms for implementing this disclosure (hereinafter referred to as embodiments). The explanation will be given in the following order.

[0011] 1. General actuator mechanisms and conventional challenges 2. Configuration and operation of the actuator mechanism of this disclosure 3. Details of the mating mechanism 4. Other operation examples 5. Modifications of the actuator mechanism 6. Example configuration of a robot device

[0012] <1. General Actuator Mechanisms and Conventional Challenges> Figure 1 illustrates the operation of a general actuator mechanism using shape memory alloy (SMA) wire (hereinafter also simply referred to as SMA).

[0013] The actuator mechanism shown in Figure 1 consists of an SMA 11 with one end fixed and an object TG connected to the other end of the SMA 11, which is the object to be driven. The SMA 11 has the property of contracting when heated during energization. For example, if one end of the SMA 11 is fixed to the ceiling or the like, the object TG suspended by the SMA 11 will repeatedly be displaced vertically (up and down in the figure) due to the contraction and expansion of the SMA 11.

[0014] In other words, at timing t1, the SMA11 is heated by turning on the power, causing the SMA11 to contract and the object TG to be displaced upward.

[0015] At timing t2, the SMA11 is cooled by turning off the power supply, causing the SMA11 to expand and the object TG to be displaced downward.

[0016] At timing t3, the SMA11 is heated by turning on the power, causing the SMA11 to contract and the object TG to be displaced upward again.

[0017] At timing t4, the SMA11 is cooled by turning off the power, causing the SMA11 to expand and the object TG to be displaced downwards again.

[0018] Figure 2 shows the displacement of the object TG and SMA11 during the operation of the actuator mechanism in Figure 1.

[0019] As shown in Figure 2, the displacement of the object TG is synchronized with the displacement of the SMA 11. However, while the SMA 11 shows high responsiveness to contraction due to energization (heating), it requires a certain cooling time Tc for cooling without energization, so its responsiveness to expansion without energization (cooling) is low. As a result, the driving responsiveness (also called frequency responsiveness) of the object TG also becomes low.

[0020] Furthermore, increasing the diameter of the SMA11 is effective in generating high stress. On the other hand, the larger the diameter of the SMA11, the longer it takes for it to cool naturally when the power is turned off, resulting in a significant decrease in responsiveness.

[0021] In contrast, a method is known that utilizes the property that the thinner the diameter of SMA, the larger the specific surface area and the faster the cooling. This method maintains the stress (generated force) generated by bundling thin wires while improving responsiveness.

[0022] However, this approach requires a number of wires equal to the square of the wire diameter, resulting in a complex structure, and necessitates sufficient air gaps when bundling the wires, leading to increased size. Furthermore, heat accumulation reduces cooling efficiency during continuous operation. While methods for accelerating cooling by contacting SMA with a cooling solvent are known, continuous operation presents challenges such as reduced cooling capacity depending on the heat capacity of the cooling solvent, and the complexity and size of mechanisms for sealing and circulating the cooling solvent.

[0023] <2. Configuration and Operation of the Actuator Mechanism of the Disclosure> The configuration and operation of an actuator mechanism to which the technology of the Disclosure is applied will be described below.

[0024] (Configuration of the actuator mechanism) Figure 3 shows an example of the configuration of the actuator mechanism of this disclosure.

[0025] The actuator mechanism 100 shown in Figure 3 displaces the target object TG by operating multiple (four in the example of Figure 3) fitting mechanisms 110-1 to 110-4 that are detachably fitted to the target object TG under the control of the control unit 101. The control unit 101 is composed of a computer such as a PC (Personal Computer), a mobile device such as a tablet or smartphone, or a dedicated terminal, and controls the operation of the actuator mechanism 100.

[0026] The actuator mechanism 100 comprises a plurality of shape memory alloy wires (SMAs) 111-1 to 111-4 (four in the example of Figure 3) with one end fixed, and each of the fitting mechanisms 110-1 to 110-4 is connected to the other end of each of the SMAs 111-1 to 111-4. Each of the SMAs 111-1 to 111-4 has the property of contracting when heated by the current.

[0027] Each of the SMA111-1 and 111-3, with one end fixed at a first fixed position (upper position in the figure), displaces the fitting mechanisms 110-1 and 110-3 connected to the other end in a first direction (upward direction in the figure) by contraction. Each of the SMA111-2 and 111-4, with one end fixed at a second fixed position (lower position in the figure) different from the first fixed position, displaces the fitting mechanisms 110-2 and 110-4 connected to the other end in a second direction (downward direction in the figure) different from the first direction by contraction.

[0028] As a result, the fitting mechanisms 110-1 and 110-3 displace the object TG in a first direction by fitting with the object TG, and the fitting mechanisms 110-2 and 110-4 displace the object TG in a second direction by fitting with the object TG. The first and second directions may be opposite directions in the vertical direction or opposite directions in the horizontal direction. In the actuator mechanism 100, the fitting mechanisms 110-1 and 110-3 are configured to displace the object TG in the first direction without interfering with each other. Similarly, the fitting mechanisms 110-2 and 110-4 are configured to displace the object TG in a second direction without interfering with each other.

[0029] Hereafter, when fitting mechanisms 110-1 to 110-4 are not distinguished, they will simply be referred to as fitting mechanism 110, and when SMA 111-1 to 111-4 are not distinguished, they will simply be referred to as SMA 111.

[0030] In the actuator mechanism 100, the fitting mechanism 110 adheres to the object TG when the connected SMA 111 is energized, and detaches from the object TG when the SMA 111 is not energized.

[0031] Specifically, the mating mechanism 110 adheres to the object TG when the SMA 111 is energized, thereby displacing the object TG. The mating mechanism 110 is detached from the object TG during the period when other mating mechanisms 110 are adhered to the object TG. Here, the period during which other mating mechanisms 110 are adhered to the object TG should include the time required for the SMA 111 connected to the mating mechanism 110 that has detached from the object TG to cool.

[0032] (Operation of Actuator Mechanism) The operation of the actuator mechanism 100 will be described with reference to Figure 4. The operation of the actuator mechanism 100 shown in Figure 4 is achieved by the control unit 101 controlling the operation of each of the fitting mechanisms 110-1 to 110-4 (adhesion / detachment from the object TG) and the ON / OFF of the power supply to each of the SMA 111-1 to 111-4.

[0033] In Figure 4, the circled numbers 1 to 4 represent either the fitting mechanisms 110-1 to 110-4 or the SMA 111-1 to 111-4, respectively.

[0034] At timing t11, the control unit 101 heats the SMA 111-1 by turning on the power supply while the fitting mechanism 110-1 is in contact with the object TG. As a result, the SMA 111-1 contracts, and the object TG is displaced in the first direction (upward in the figure).

[0035] At timing t12, the control unit 101 detaches the fitting mechanism 110-1 from the object TG, turns off the power supply to the SMA 111-1, and heats the SMA 111-2 by turning on the power supply while the fitting mechanism 110-2 is attached to the object TG. As a result, the SMA 111-2 contracts, and the object TG is displaced in the second direction (downward in the figure).

[0036] At timing t13, the control unit 101 detaches the fitting mechanism 110-2 from the object TG, turns off the power supply to the SMA 111-2, and heats the SMA 111-3 by turning on the power supply while the fitting mechanism 110-3 is attached to the object TG. As a result, the SMA 111-3 contracts, and the object TG is displaced again in the first direction (upward in the figure).

[0037] At timing t14, the control unit 101 detaches the fitting mechanism 110-3 from the object TG, turns off the power supply to the SMA 111-3, and heats the SMA 111-4 by turning on the power supply while the fitting mechanism 110-4 is attached to the object TG. As a result, the SMA 111-4 contracts, and the object TG is displaced again in the second direction (downward in the figure).

[0038] Thereafter, by repeating the operations after timing t11, the object TG repeats displacements in the first direction and the second direction.

[0039] At this time, during timings t12 to t14, since the SMA111-1 is cooled (naturally cooled) by turning off the power supply, the SMA111-1 can shift to the operation at timing t11 in the extended state.

[0040] FIG. 5 is a diagram showing displacements of the object TG and the SMA111-1 to 111-4 in the operation of the actuator mechanism 100 of FIG. 4.

[0041] In FIG. 5, the displacement of the object TG is synchronized only with the displacement during contraction due to energization (heating) of each of the SMA111-1 to 111-4, and is not affected by the elongation due to non-energization (cooling) of each of the SMA111-1 to 111-4. That is, the displacement of the object TG is realized only by the operation of each fitting mechanism 110 during the contraction of each SMA111 showing high responsiveness.

[0042] Referring to the flowchart of FIG. 6, the drive process of the object TG by the actuator mechanism 100 will be described. Here, the operation in the case of driving the object TG by two fitting mechanisms 110 (the first fitting mechanism and the second fitting mechanism) will be described.

[0043] In step S1, the control unit 101 adheres the first fitting mechanism to the object TG. At this time, it is assumed that the object TG is at the initial position.

[0044] In step S2, the control unit 101 turns on the power supply of the SMA111 (the first SMA) connected to the first fitting mechanism.

[0045] In step S3, the first SMA contracts by being heated by energization. As a result, the object TG adhered to the first fitting mechanism is displaced in the first direction from the initial position.

[0046] In step S4, the control unit 101 adheres the second fitting mechanism to the object TG.

[0047] In step S5, the control unit 101 detaches the first fitting mechanism from the object TG.

[0048] In step S6, the control unit 101 turns off the energization of the first SMA that has been detached from the first fitting mechanism.

[0049] In step S7, the control unit 101 turns on the energization of the SMA111 (second SMA) connected to the second fitting mechanism.

[0050] In step S8, the second SMA shrinks by being heated by energization. As a result, the object TG adhered to the second fitting mechanism is displaced in the second direction and returns to the initial position.

[0051] In step S9, the control unit 101 adheres the first fitting mechanism to the object TG.

[0052] In step S10, the control unit 101 detaches the second fitting mechanism from the object TG.

[0053] In step S11, the control unit 101 turns off the energization of the second SMA that has been detached from the second fitting mechanism.

[0054] Thereafter, it returns to step S2, the energization of the first SMA is turned on, and the subsequent processing is repeated. At this time, between steps S6 and S11, the first SMA has returned to its original length by expanding due to cooling (non-energization). That is, the first SMA can contract again by being energized.

[0055] According to the above configuration and processing, a plurality of fitting mechanisms are adhered to and detached from the object in accordance with the contraction and expansion of the SMA, enabling continuous operation without depending on the cooling time of the SMA, and realizing highly responsive driving.

[0056] Also, compared with a configuration using a cooling solvent, a wire coating and a cooling solvent circulation device are not required, so the entire actuator mechanism can be downsized, and sealing etc. is also not required, making processing easy and improving durability.

[0057] Furthermore, by creating a multi-layered mating mechanism according to the application, it becomes possible to achieve high overall responsiveness even with wires that are relatively thick and require a long cooling time.

[0058] The actuator mechanism 100 may have, for example, a continuous operation mode in which each fitting mechanism 110 operates in succession, as described with reference to Figure 4, and an individual operation mode in which each fitting mechanism 110 operates, for example, in response to user instructions. In this case, these operation modes may be switched depending on the application, for example, the driving of the object TG.

[0059] Furthermore, even if, for example, the SMA 111-2 and 111-4 in the actuator mechanism 100 are replaced with springs, and the fitting mechanisms 110-2 and 110-4 are always adhered (fitted) to the object TG, the operation described with reference to Figure 4 is still possible.

[0060] <3. Details of the Mating Mechanism> In the actuator mechanism 100 described above, the mating mechanism 110 should be able to adhere to or detach from the object TG by the operation of the mating portion by any small actuator. The small actuator may be composed of a thermal actuator, electrostatic actuator, MEMS (Micro Electro Mechanical Systems), etc., having an extremely small structure such as a thin film or ultrafine, or it may be composed of an ultrafine shape memory alloy wire (ultrafine SMA) that is thinner than the shape memory alloy wire (SMA) 111 described above.

[0061] Now, with reference to Figure 7, the details and operation of the fitting mechanism 110 having an ultra-fine SMA will be described.

[0062] Figure 7 shows a detailed configuration example of one fitting mechanism 110 and its operation from adhesion to detachment from the object TG.

[0063] As shown in Figure 7, in the fitting mechanism 110, the opposite side of the portion to which the SMA 111 is connected is supported by a coil spring 121. The coil spring 121 stabilizes the operation (displacement) of the fitting mechanism 110 due to the contraction and extension of the SMA 111.

[0064] The fitting mechanism 110 is configured to include a fitting portion 131, an ultrafine SMA 132, and a coil spring 133. The fitting portion 131 is composed of a member that extends along the bonding surface with the object TG. Each end of the fitting portion 131 is supported from the opposite side of the bonding surface with the object TG by the ultrafine SMA 132 and the coil spring 133. The fitting portion 131 is configured to rotate around its center axis, and when heated by current, the ultrafine SMA 132 contracts, causing the end on the coil spring 133 side to protrude towards the object TG. With this structure, the fitting mechanism 110 can be detachably fitted to the object TG.

[0065] In the example shown in Figure 7, the ultrafine SMA 132 is formed with a thinner wire diameter than the SMA 111, and the ultrafine SMA 132 is switched ON / OFF simultaneously with the SMA 111. For example, the wire diameter of the ultrafine SMA 132 is 37 μm, and the wire diameter of the SMA 111 is 200 μm. As a result, when the SMA 111 and the ultrafine SMA 132 are switched ON at the same time, the ultrafine SMA 132, which has a thinner wire diameter, heats up and shrinks first. Also, when the SMA 111 and the ultrafine SMA 132 are switched OFF at the same time, the ultrafine SMA 132, which has a thinner wire diameter, cools down and expands first.

[0066] Next, we will explain the operation of the fitting mechanism 110 from adhesion to detachment from the object TG.

[0067] At timing t20, with the object TG in its initial position, the heating of the SMA111 and the ultrafine SMA132 begins when the power is turned ON.

[0068] At timing t21, the extremely thin SMA 132 (37 μm SMA), which has a thin wire diameter, shrinks due to heating, causing the fitting portion 131 to operate as shown by the dashed frame A1 in the figure, and the fitting mechanism 110 to adhere to the object TG.

[0069] Then, at timing t23, the thicker diameter SMA 111 (200 μm SMA) shrinks due to heating, causing the object TG to be displaced together with the fitting mechanism 110.

[0070] Subsequently, the cooling of the SMA 111 and the ultrafine SMA 132 begins when the power is turned off. That is, at timing t24, the ultrafine SMA 132 (37 μm SMA), which has a thin wire diameter, expands due to cooling, causing the fitting portion 131 to operate as shown by the dashed frame A2 in the figure, and the fitting mechanism 110 to detach from the object TG.

[0071] With the above configuration and operation, a series of operations such as bonding the mating mechanism 110 to the object TG, driving the object TG, and detaching it from the object TG can be achieved simply by turning the SMA ON / OFF.

[0072] <4. Other Operation Examples> In the above, we have described an operation of the actuator mechanism 100 that achieves a drive with high frequency response (see Figure 5). However, the actuator mechanism 100 is not limited to this and can perform various operations depending on the operating timing of the mating mechanism 110 and the SMA 111.

[0073] For example, the actuator mechanism 100 operates the fitting mechanism 110 and SMA 111 in the order of the circled numbers 1, 3, 2, and 4 in Figure 4. In this case, fitting mechanism 110-1 displaces the object TG in a first direction, and fitting mechanism 110-3 further displaces the object TG that has been displaced in the first direction in the first direction. Also, fitting mechanism 110-2 displaces the object TG in a second direction, and fitting mechanism 110-4 further displaces the object TG that has been displaced in the second direction in the second direction.

[0074] Figure 8 shows the displacement of the object TG and SMA111-1 to 111-4 during the operation of such an actuator mechanism 100.

[0075] Similar to Figure 5, in Figure 8, the displacement of the object TG is synchronized only with the displacement during contraction caused by the energization (heating) of each of the SMA111-1 to 111-4, and is not affected by the expansion caused by the de-energization (cooling) of each of the SMA111-1 to 111-4. However, in the example of Figure 8, the object TG is displaced in two stages in the first direction due to the contraction of SMA111-1 and 111-3, and then displaced in two stages in the second direction due to the contraction of SMA111-2 and 111-4. In other words, the operation shown in Figure 8 makes it possible to achieve a drive with a large stroke (amount of displacement).

[0076] Alternatively, the actuator mechanism 100 may be operated by first simultaneously operating the fitting mechanisms 110 and SMA 111 indicated by circled numbers 1 and 3 in Figure 4, and then simultaneously operating the fitting mechanisms 110 and SMA 111 indicated by circled numbers 2 and 4. In this case, fitting mechanisms 110-1 and 110-3 simultaneously displace the object TG in a first direction. Also, fitting mechanisms 110-2 and 110-4 simultaneously displace the object TG in a second direction.

[0077] Although not shown in the diagram, this type of operation allows for a similar stroke of the object TG as in the example in Figure 5, but the force displacing the object TG is doubled, making it possible to achieve a drive with a larger generated force.

[0078] <5. Modified Actuator Mechanisms> In the above, each fitting mechanism 110 in the actuator mechanism 100 displaces the object in the same direction as the contraction direction of the SMA 111. However, depending on the structure of the fitting mechanism 110, the fitting mechanism 110 can also be configured to displace the object TG in a direction different from the contraction direction of the SMA 111.

[0079] Figure 9 shows a modified example of the actuator mechanism of the present disclosure.

[0080] The actuator mechanism 100A shown in Figure 9 displaces the object TG by operating two fitting mechanisms 110-1 and 110-2 that are detachably fitted to the object TG to be driven, under the control of the control unit 101.

[0081] In the actuator mechanism 100A, SMA111-1, with one end fixed in a first fixed position (upper position in the figure), rotates the fitting mechanism 110-1 connected to the other end clockwise in the figure by contracting. SMA111-2, with one end fixed in a second fixed position (lower position in the figure), rotates the fitting mechanism 110-2 connected to the other end clockwise in the figure by contracting.

[0082] In the actuator mechanism 100A, the fitting mechanisms 110-1 and 110-2 are formed with pinions that fit with the object TG, and the object TG is formed with a rack into which the fitting mechanisms 110-1 and 110-2 fit. In other words, the actuator mechanism 100A constitutes a rack and pinion that converts the rotational force of the fitting mechanisms 110-1 and 110-2 into the linear motion of the object TG. Note that any mechanism can be used for the mechanism by which the fitting mechanisms 110-1 and 110-2 adhere to or detach from the object TG.

[0083] With this configuration, the actuator mechanism 100A allows the fitting mechanism 110 to displace the object TG in a direction perpendicular to the contraction direction of the SMA 111.

[0084] <6. Examples of Robot Device Configurations> The technology described herein can be applied to robot devices having various actuator mechanisms.

[0085] Figure 10 shows an example of the hardware configuration of a robot having an actuator mechanism to which the technology described herein is applied.

[0086] The robot 200 shown in Figure 10 is configured, for example, as a four-legged dog-type entertainment robot. However, it is not limited to this, and the robot 200 may be configured as an industrial robot used in factories, or as a flying robot equipped with bird-like wings or insect-like feathers that can flap their wings or feathers to levitate and fly.

[0087] The robot 200 is configured to include a sensor 210, a controller 220, and an actuator 230.

[0088] Sensor 210 is configured as an RGB camera equipped with an image sensor such as a CMOS (Complementary Metal Oxide Semiconductor) image sensor, or as a distance measuring sensor such as a 3D ToF (Time of Flight) sensor. Sensor 210 senses the surrounding environment of the robot 200 and supplies the obtained sensing information to the controller 220.

[0089] The controller 220 has a built-in CPU (Central Processing Unit) and memory, and performs various processes by executing programs stored in memory via the CPU. Specifically, the controller 220 generates control signals to control the actuator 230 based on sensing information from the sensor 210.

[0090] The actuator 230 is a mechanical element for driving, for example, to drive a manipulator or joint (not shown). That is, the actuator 230 is driven by a control signal from the controller 220, enabling various motions of the robot 200 using the manipulator or joint. In this case, the actuator 230 functions as an artificial muscle. Furthermore, if the robot 200 is configured as a flying robot equipped with wings or feathers, the actuator 230 functions as an artificial muscle to flap the wings or feathers.

[0091] Furthermore, by employing an actuator mechanism incorporating the technology described herein as the actuator 230, it becomes possible to achieve highly responsive driving in the continuous motion of the robot 200, for example. Additionally, miniaturization of the entire actuator mechanism becomes possible, thus enabling miniaturization of the robot 200 as a whole. In particular, by using the actuator mechanism incorporating the technology described herein as an artificial muscle for flapping the wings or feathers of the aforementioned flying robot, it becomes possible to satisfy the requirements for high frequency response, high force generation, and high stroke required for such a flapping mechanism.

[0092] Furthermore, the actuator mechanism to which the technology described herein is applied can be used not only as the actuator 230 of the robot 200 described above, but also in other applications such as the operating mechanism of the tip of an endoscope, the image stabilization mechanism of a camera, the opening and closing mechanism of a valve, and the linear actuator of a massage chair.

[0093] The embodiments of this disclosure are not limited to those described above, and various modifications are possible without departing from the spirit of this disclosure.

[0094] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0095] Furthermore, the technology relating to this disclosure can take the following configurations: (1) An actuator mechanism comprising a plurality of shape memory alloy wires, one end of which is a fixed end, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires and detachably fitted to an object to be driven, wherein the fitting mechanisms are bonded to the object when the shape memory alloy wires are energized and detached from the object when the shape memory alloy wires are not energized. (2) The actuator mechanism according to (1), wherein the shape memory alloy wires have the property of shrinking when heated by energization, and the fitting mechanisms displace the object by being bonded to the object when the shape memory alloy wires are energized. (3) The actuator mechanism according to (2), wherein the fitting mechanism is detached from the object during the period when the other fitting mechanisms are bonded to the object. (4) The actuator mechanism according to (3), wherein the period includes the time required for the shape memory alloy wires connected to the fitting mechanism that has been detached from the object to cool. (5) The actuator mechanism according to any one of (2) to (4), wherein the fitting mechanism includes a first fitting mechanism for displacing the object in a first direction and a second fitting mechanism for displacing the object displaced in the first direction in a second direction different from the first direction. (6) The actuator mechanism according to any one of (2) to (4), wherein the fitting mechanism includes a first fitting mechanism for displacing the object in a first direction and a second fitting mechanism for further displacing the object displaced in the first direction in the first direction. (7) The actuator mechanism according to any one of (2) to (6), wherein the fitting mechanism displaces the object in the same direction as the contraction direction of the shape memory alloy wire. (8) The actuator mechanism according to any one of (2) to (6), wherein the fitting mechanism displaces the object in a direction different from the contraction direction of the shape memory alloy wire. (9) The actuator mechanism according to any one of (2) to (8), wherein the fitting mechanism is bonded to or detached from the object by the movement of the fitting portion by a small actuator.(10) The actuator mechanism according to (9), wherein the small actuator is composed of an ultrafine shape memory alloy wire thinner than the shape memory alloy wire. (11) A robot device having an actuator mechanism comprising a plurality of shape memory alloy wires with one end fixed, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires and detachably fitted to an object to be driven, wherein the fitting mechanisms are bonded to the object when the shape memory alloy wires are energized and detached from the object when the shape memory alloy wires are not energized. (12) The robot device according to (11), configured as a flying robot equipped with wings or feathers, wherein the actuator mechanism functions as an artificial muscle that flaps the wings or feathers.

[0096] 100 Actuator mechanism, 101 Control unit, 110, 110-1 to 110-4 Fitting mechanism, 111, 111-1 to 111-4 SMA, 121 Coil spring, 131 Fitting part, 132 Ultra-fine SMA, 133 Coil spring, 200 Robot, 210 Sensor, 220 Controller, 230 Actuator

Claims

1. An actuator mechanism comprising a plurality of shape memory alloy wires, one end of which is a fixed end, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires, which are detachably fitted to an object to be driven, wherein the fitting mechanisms are bonded to the object when the shape memory alloy wires are energized and detached from the object when the shape memory alloy wires are not energized.

2. The actuator mechanism according to claim 1, wherein the shape memory alloy wire has the property of shrinking when heated during energization, and the fitting mechanism is bonded to the object when the shape memory alloy wire is energized, thereby displacing the object.

3. The actuator mechanism according to claim 2, wherein the fitting mechanism is detached from the object during the period in which the other fitting mechanism is bonded to the object.

4. The actuator mechanism according to claim 3, wherein the period includes the time required for the shape memory alloy wire connected to the fitting mechanism that has been detached from the object to be cooled.

5. The actuator mechanism according to claim 2, wherein the fitting mechanism includes a first fitting mechanism for displacing the object in a first direction, and a second fitting mechanism for displacing the object displaced in the first direction in a second direction different from the first direction.

6. The actuator mechanism according to claim 2, wherein the fitting mechanism includes a first fitting mechanism for displacing the object in a first direction, and a second fitting mechanism for further displacing the object that has been displaced in the first direction in the first direction.

7. The actuator mechanism according to claim 2, wherein the fitting mechanism displaces the object in the same direction as the contraction direction of the shape memory alloy wire.

8. The actuator mechanism according to claim 2, wherein the fitting mechanism displaces the object in a direction different from the contraction direction of the shape memory alloy wire.

9. The actuator mechanism according to claim 2, wherein the fitting mechanism is bonded to or detached from the object by the operation of the fitting portion by a small actuator.

10. The actuator mechanism according to claim 9, wherein the small actuator is composed of an ultrafine shape memory alloy wire that is thinner than the shape memory alloy wire.

11. A robotic device comprising a plurality of shape memory alloy wires, one end of which is a fixed end, and a plurality of fitting mechanisms connected to the other end of each of the shape memory alloy wires, which are detachably fitted to an object to be driven, wherein the fitting mechanisms are actuator mechanisms that adhere to the object when the shape memory alloy wires are energized and detach from the object when the shape memory alloy wires are not energized.

12. The robotic device according to claim 11, configured as a flying robot having wings or feathers, wherein the actuator mechanism functions as an artificial muscle for flapping the wings or feathers.

Images