Actuator assembly

Abstract

The present invention generally relates to an actuator assembly for facilitating or resisting movement of a body relative to a support structure thereof. More specifically, the actuator assembly includes one or more smart material actuators that mechanically contract when subjected to a stimulus, thereby creating a force acting on the body to promote or resist movement of the body relative to the support structure.

Description

TECHNICAL FIELD

[0001] The present invention relates generally to an actuator device for facilitating or resisting movement of an object connected or attached thereto. More specifically, the actuator device comprises one or more smart material actuators that mechanically contract upon being stimulated, thereby generating a force acting on the actuator to facilitate or resist movement of an object connected or attached thereto. BACKGROUND

[0002] An actuator is generally a device responsible for effecting physical movement in a mechanical system. Thus, actuators are widely used whenever physical movement of components of a mechanical system is required. Physical movement is achieved by converting energy from an energy source into mechanical force.

[0003] Various types include soft actuators, hydraulic actuators, pneumatic actuators, electric actuators, thermal actuators, magnetic actuators, mechanical actuators.

[0004] While various types of actuators are commercially available, there is still a need for further development, e.g. to minimize the overall weight of the system, to increase the response rate of the system and / or to increase the functionality of the new system.

[0005] Hence, an improved actuator device for facilitating or resisting movement would be advantageous. SUMMARY

[0006] According to a first aspect, an actuator assembly is provided. The actuator assembly comprises a support structure, a body supported by the support structure, at least a first anchoring region attached to the support structure, at least a second anchoring region attached to the body, at least one first smart material actuator (SMA) connected between the first anchoring region and the second anchoring region and forming a first set of SMAs in a first SMA group. Further, the assembly comprises a force transmission mechanism connecting the first anchoring region to the second anchoring region and comprising the first SMA group. Each SMA is arranged to operate in an idle state and in an activated state triggered by a non-mechanical stimulus causing the associated SMA to mechanically contract. Further, an activation unit is arranged to send said non-mechanical stimulus individually to each SMA in response to a defined activation sequence.

[0007] The first set of SMAs in the first SMA group can comprise two or more SMAs arranged in sequence between the first anchoring region and the second anchoring region.

[0008] The force transmission mechanism can include one or more links, where each link can include at least one of a fiber, a yarn, a cable, a wire, a film, or a strip. The one or more links can be rigid, inelastic, or non-elastic.

[0009] The force transmission mechanism can include a first end anchored to the first anchor region or the second anchor region and a second end attached to at least one sequential SMA.

[0010] The force transmission mechanism can include at least one of: a first link connected between a first anchor region and a SMA closest in sequence to the first anchor region and attached to the first anchor region and the SMA; a second link connected between two closest adjacent SMAs and attached to the SMAs; and a third link connected between a second anchor region and a SMA closest in sequence to the second anchor region and attached to the second anchor region and the SMA.

[0011] The at least two SMAs connected in sequence can form part of a laterally separated or laterally attached array of SMAs and can include more than one group of SMAs.

[0012] The subgroups of SMAs in each group of SMAs can be arranged to act as springs to allow the subgroups to contract upon activation of the respective subgroup SMAs or to extend upon deactivation of the respective subgroup SMAs.

[0013] The associated force transmission mechanism of at least one of the groups of SMAs can further include a spring, damper, or elastic member sequentially located between a respective first anchor region and a respective second anchor region.

[0014] Each SMA can be selected from the group consisting of: a photoresponsive actuator; a dielectric or electrorestrictive elastomer actuator (DEA); a conductive polymer actuator (CP); an electroactive polymer actuator (EAP); and a magnetostrictive actuator (MA).

[0015] The array of SMAs can be provided as an array of thin films configured to conform to a curvature of the subject.

[0016] The thin films can include a transparent coating or a plastic film applied over the array of SMAs, where the transparent coating or the plastic film can be arranged to transmit actuation forces through its structure.

[0017] The first set of SMAs can be connected in sequence between a first anchor region and a second anchor region along a first direction.

[0018] The first group of SMAs can further include a second set of SMAs connected in sequence between the first anchor region and the second anchor region along a second direction different from or parallel to the first direction.

[0019] The first set of SMAs can further include at least a third set of SMAs having two further smart material actuators (SMAs) sequentially connected between the first anchor region and the second anchor region. The third set of SMAs can be sequentially connected between the first anchor region and the second anchor region along a third direction. The third direction can be different from the first direction or the second direction, or parallel to the first direction or the second direction.

[0020] The first set of SMAs, the second set of SMAs, or the third set of SMAs in the first set of SMA groups can be formed in an array.

[0021] The first set of SMAs in the first set of SMA groups can be arranged in a first layer, and the second set of SMAs in the first set of SMA groups can be arranged in a second layer. The second layer can at least partially overlap the first layer.

[0022] The activation unit can be releasably or fixedly attached to the support structure.

[0023] At least one of the SMAs can be a light-responsive actuator. The activation unit can include a light source for sending light to activate the at least one SMA.

[0024] The activation unit can further include a light guide arranged to receive light from the light source and direct the received light toward the at least one associated SMA.

[0025] The activation unit can include a light-emitting diode (LED) panel including at least one LED for each SMA. One or more LEDs of the LED panel can have a spatial configuration corresponding to a spatial configuration of an associated SMA.

[0026] The activation unit can include a flexible light-emitting diode (LED) panel including at least one LED for each SMA. One or more LEDs of the flexible LED panel can have a spatial configuration corresponding to a spatial configuration of an associated SMA.

[0027] The activation unit can include one or more LEDs attached to a flexible printed circuit board (PCB).

[0028] The activation unit can include one or more LED groups, each of which can be arranged to activate one or more associated SMAs in a respective SMA group.

[0029] The body can be arranged to move relative to the support structure upon activation or deactivation of at least one of the SMAs.

[0030] The actuator assembly can further comprise a connector unit attached to the body and arranged to be connected to a further component.

[0031] The further component can be selected from the group comprising: an electronic device, an electromechanical device, a mechanical device, a remote control device, an aerospace component, a payload, a tool, a robotic member, and a control surface.

[0032] The body can have a spherical shape, a circular shape, or an elliptical shape.

[0033] The support structure can comprise a plurality of ball bearings supporting the body, thereby allowing the body to move or roll relative to the support structure.

[0034] The support structure can comprise a conical portion, a hollow pyramidal portion, a cup-shaped portion, or a socket portion, such as a ball bearing socket, for holding the body. The body can have a shape corresponding to the shape of the socket portion.

[0035] The actuator assembly can further comprise a second smart material actuator (SMA) group connected between a further first anchoring region and a further second anchoring region.

[0036] The second smart material actuator group can be at least partially oppositely arranged to the first group of first smart material actuators, thereby forming a first excitation-antagonistic SMA pair.

[0037] The further second anchoring region of the second SMA group can be oppositely arranged to the second anchoring region of the first SMA group with respect to a first bisecting axis of the body.

[0038] The actuator assembly can further comprise: a third smart material actuator (SMA) group connected between a further first anchoring region and a further second anchoring region; and a fourth smart material actuator (SMA) group connected between a further first anchoring region and a further second anchoring region. The third smart material actuator group can be at least partially oppositely arranged to the fourth group of first smart material actuators, thereby forming a second excitation-antagonistic SMA pair.

[0039] The further second anchoring region of the third SMA group can be oppositely arranged to the second anchoring region of the fourth SMA group with respect to a first bisecting axis of the body.

[0040] The actuator assembly can further comprise: a fifth group of smart material actuators (SMA) connected between a further first anchoring region and a further second anchoring region; and a sixth group of smart material actuators (SMA) connected between the further first anchoring region and the further second anchoring region. The fifth group of smart material actuators can be arranged at least partially opposite the sixth group of smart material actuators, thereby forming a third agonist-antagonist SMA pair.

[0041] The further second anchoring region of the fifth group of SMA can be arranged opposite the second anchoring region of the sixth group of SMA with respect to a second bisecting axis (central axis) of the body.

[0042] The second anchoring region of the first group of SMA can be arranged 180 degrees along the body perimeter from the second anchoring region of the second group of SMA.

[0043] The second anchoring region of the third group of SMA can be arranged 180 degrees along the body perimeter from the second anchoring region of the fourth group of SMA.

[0044] The second anchoring region of the first group of SMA can be arranged 90 degrees along the body perimeter from the second anchoring region of the third group of SMA. The second anchoring region of the second group of SMA can be arranged 90 degrees along the body perimeter from the second anchoring region of the fourth group of SMA.

[0045] The third agonist-antagonist SMA pair can be arranged substantially orthogonal to the first agonist-antagonist SMA pair and the second agonist-antagonist SMA pair.

[0046] The respective second anchoring regions can be arranged on the outer surface, offset from a second bisecting axis (central axis) of the body, thereby allowing tangential pulling. BRIEF DESCRIPTION OF DRAWINGS

[0047] Some examples will now be described by way of example with reference to the following drawings:

[0048] Figure 1 a side view of an actuator assembly comprising a first group of SMA according to a first example in its idle state is illustrated;

[0049] Figure 2 a side view of the actuator assembly of Figure 1 in its activated state, i.e. where at least one or more SMA of the first group of SMA have been activated;

[0050] Figure 3 a side view of an actuator assembly according to another example in its idle state, the actuator assembly comprising another group of smart material actuators is illustrated;

[0051] Figure 4 a side view of the actuator assembly of Figure 3 in its activated state, i.e. where at least one or more of the SMAs of the first SMA group have been activated;

[0052] Figure 5 a side view of the actuator assembly according to yet another example in its idle state, where the respective portions of the activation unit 30 are arranged close to the respective SMA groups;

[0053] Figure 6 a side view of the actuator assembly of Figure 5 in its activated state;

[0054] Figure 7 a side view of the actuator assembly according to another example (similar to the actuator assembly of Figure 5 in its idle state, the actuator assembly comprising at least one spring member arranged to return the body of the actuator assembly to its idle position upon deactivation of one or more of the SMAs of the first SMA group;

[0055] Figure 8 a side view of the actuator assembly of Figure 7 in its activated state, where at least one or more of the SMAs of the first SMA group have been activated, the spring member having reached an extended state;

[0056] Figure 9 a side view of the actuator assembly according to another example, the actuator assembly comprising three groups of smart material actuators in their idle state;

[0057] Figure 10 a side view of the actuator assembly of Figure 9 in its activated state, where at least some of the SMAs of the first SMA group have been activated;

[0058] Figure 11 a side view of the actuator assembly according to another example in its idle state, the actuator assembly comprising three groups of smart material actuators, where each SMA group is connected to a series spring member;

[0059] Figure 12 a side view of the actuator assembly of Figure 11 in its activated state, where at least some of the SMAs of the first SMA group have been activated, and thus the series spring member of the second SMA group arranged opposite the first SMA group has reached an extended state;

[0060] Figure 13A top view of an actuator assembly in its idle state, according to another example, is shown, which includes four SMA groups and forms two excitation-antagonistic SMA pairs.

[0061] Figure 14 A side view of an actuator assembly in its idle state, according to yet another example, is shown, the actuator assembly comprising six SMA groups (in Figure 14 (The two SMA groups located on the back side are not shown in the image) and form three agonist-antagonist SMA pairs;

[0062] Figure 15 Examples Figure 14 A top view of the actuator assembly in its idle state, showing six SMA groups forming three excitation-antagonistic SMA pairs;

[0063] Figure 16 A side view of an actuator assembly according to yet another example is shown, which has a cup-shaped support structure for holding its body.

[0064] Figure 17 A side view of an actuator assembly according to yet another example is shown, which has a tapered support structure for holding its body in place;

[0065] Figure 18a and Figure 18b Top views of sequentially connected SMA groups in both idle and active states are shown respectively; and

[0066] Figure 19 A top view of a 1D array of light-responsive smart actuators, based on an example, is shown. Detailed Implementation

[0067] The general idea of ​​this invention is to provide an actuator assembly comprising one or more discrete smart material actuators (SMAs) that mechanically contract upon non-mechanical stimulation to generate a force transmitted to one or more anchorage zones of the actuator. The actuator may include a support structure. The actuator may also include a body supported by the support structure.

[0068] Actuator assemblies can be used to facilitate or resist movement of a subject relative to its supporting structure. When smart material actuators are stimulated / activated, they contract mechanically, thereby generating a force acting on the subject to facilitate or resist movement of the subject relative to the supporting structure.

[0069] An anchoring region can be arranged to the body. The force generated by the activation of the smart material actuator is transmitted to the body via the anchoring region using a force transmission mechanism (FTM). The force generated by the activation of the SMA allows the body to attain a desired orientation and / or position relative to the support structure. The body can be configured to move relative to the support structure, which in turn allows the body to attain various relative orientations relative to the support structure. Depending on the type of application, the generated force can be used to resist movement of the body, or to facilitate a desired movement of the body.

[0070] As will be further elucidated below, the movement can involve three-dimensional (3D), two-dimensional (2D) and / or one-dimensional (1D) movement.

[0071] In some examples, the magnitude of the generated force can be changed by changing the magnitude of the non-mechanical stimulus.

[0072] In at least one example, the actuator further comprises a connector unit that is attachable, such as releasably or rigidly attachable, to the body. The connector unit can also be arranged to be connected to a further component. As the connector unit is attached to the body, the connector unit will inherently move relative to the support structure based on the activation and / or deactivation of the SMA.

[0073] In at least one example, the actuator assembly is arranged to function as a rotation actuator.

[0074] In at least one example, the actuator assembly functions as a gimbal and / or stabilizer unit for a further component.

[0075] The further component can relate to an electronic device, an electromechanical device, a mechanical device, a remote control device, an aerospace component, a payload, a tool, a robotic member, a control surface.

[0076] In at least one example, the further component relates to a camera. This allows the actuator assembly to function as a gimbal and / or stabilizer for the camera.

[0077] In some examples, the actuator assembly can be used as a fitness device, wherein a user is used to resist the force generated upon activation of the associated smart material actuator.

[0078] In other examples, the actuator assembly can be used as a medical rehabilitation device, allowing a patient with impaired mobility to achieve a higher degree of mobility, for example by connecting a fitness or training device to the connector unit of the actuator assembly as disclosed herein.

[0079] Reference Figure 1Fig. 1 shows a first example of an actuator assembly 100. The actuator assembly can be used to act as a gimbal and / or stabilizer unit for a further component. In some examples, the further component can relate to a camera or the like, which can allow the actuator assembly to act as a gimbal and / or stabilizer thereof.

[0080] The actuator assembly 100 can comprise a support structure 101. The actuator assembly can further comprise a main body 102 supported by the support structure 101. Furthermore, the actuator assembly can comprise at least a first anchor region 11 (e.g. first anchor region 11a) attached to the support structure 101 and / or at least a second anchor region 12 (e.g. second anchor region 12a) attached to the main body 102. The actuator assembly 100 can further comprise at least one first smart material actuator (SMA) 21 connected between the first anchor region 11 and the second anchor region 12, thereby forming a first set of SMAs in a first SMA group. Furthermore, the actuator assembly 100 can comprise a force transmission mechanism 20 connecting the first anchor region 11 to the second anchor region 12, and can comprise the first SMA group.

[0081] Each SMA 21 can be arranged to operate in an idle state (or inactive state) and an active state. The active state can be triggered by a stimulus (e.g. a non-mechanical stimulus) causing the associated SMA to mechanically contract.

[0082] Furthermore, the actuator assembly 100 can comprise an activation unit 30 which can be arranged to send said stimulus to each SMA individually in response to a defined activation sequence.

[0083] Unlike using a long SMA (e.g. a SMA fibre or yarn extending fully between two or more anchor regions), using discrete SMAs connected in series between two or more anchor regions can achieve a desired overall force while taking advantage of the higher response rate of the discrete SMAs.

[0084] Furthermore, arranging two or more SMAs in series allows for activation of multiple SMAs in a sequence in a local region between two anchor regions. When combined with activation of additional sets and / or groups of serially adjacent SMAs in a second local region, various types of forces (e.g. torsion) can be generated. These forces allow the actuator assembly 10 to be more versatile and allow the assembly to resist or facilitate various movements in use.

[0085] The first set of SMAs in each group can be connected in series between the first anchor region and the second anchor region along a first direction, such as a longitudinal direction. The first set of SMAs in the first SMA group 21 can comprise two or more SMAs 21 arranged in series between the first anchor region 11 and the second anchor region 12.

[0086] The technical effect of the force transmission mechanism is to transmit the force, such as a pulling force, generated by each activated SMA between the respective activated SMA and the anchoring regions 11 and 12. Since at least two SMAs are connected in series between the first anchoring region 11 and the second anchoring region 12, upon activation of the associated SMA, the force transmission mechanism will serve to pull or push the first anchoring region towards or away from the second anchoring region or vice versa. Thus, for example in the activated state, in response to activation, the generated force serves to reduce the longitudinal distance between the first anchoring region 11 and the second anchoring region 12 compared to the idle state.

[0087] In the absence of an external force or counterforce acting in the longitudinal direction opposite to the longitudinal direction of the generated force and equal to or greater than the generated force, the longitudinal distance between the two anchoring regions will decrease.

[0088] When the external force or counterforce is equal to the generated force, the longitudinal distance will remain unchanged.

[0089] When the external force or counterforce is greater than the generated force, the longitudinal distance will increase.

[0090] In some examples, the counterforce can be applied by a further component.

[0091] In some examples, the associated SMA is controlled to generate the force depending on the magnitude of the external force or counterforce or depending on a sensed movement of the further component associated with the external force or counterforce.

[0092] In some examples, the body 102 is arranged to move relative to the support structure 101 upon activation or deactivation of at least one of the SMAs. The body 102 can have a spherical shape, a circular shape or an elliptical shape.

[0093] The support structure 101 can be configured to support the body 102. The support provided by the support structure 101 to the body 102 allows the body 102 to move or roll relative to the support structure 101. The support member 101 can comprise a conical portion, a hollow pyramid-shaped portion, a cup-shaped portion and / or a socket portion (e.g. a ball bearing socket). The body 102 can comprise a shape complementary or corresponding to the shape of the support structure 101 (e.g. a shape corresponding to the socket portion of the support structure 101).

[0094] In some examples, the support structure 101 comprises one or more ball bearings for supporting the body 102.

[0095] The actuator assembly 100 can further comprise a connector unit 40 attached to the body 102 and arranged to be connected to a further component.

[0096] The further component can be selected from, but not limited to, the group comprising: electronic devices, electromechanical devices, mechanical devices, remote control devices, aerospace components, payloads, tools, robotic components and control surfaces.

[0097] As will be further set out below, in some examples, the magnitude of the force generated by the activation of the associated SMA is adjusted to continuously match the magnitude of the force of the body 102 and / or the further component, such that the distance between the first and second anchoring regions 11, 12 remains constant or substantially constant. This allows force feedback to be provided, thereby allowing the force and / or the movement of the body 102 fixed to the first and / or second anchoring regions to be eliminated in use. This also allows the actuator assembly to act as a stabiliser and / or gimbal. Thus, the associated SMA can be controlled to generate a force that matches the counter-force, thereby maintaining the distance between the first and second anchoring regions constant or substantially constant.

[0098] The counter-force can be associated with the force from the body 22 and / or the further component.

[0099] A controller (not shown) can be operatively coupled to the activation unit 30 and / or can be configured to execute an activation sequence in order to control the activation unit 30.

[0100] The controller can be a microcontroller operatively coupled to a memory and arranged to execute a plurality of computer executable instructions, optionally stored on a non-transitory computer readable medium. The processor can be operatively coupled to control circuitry for controlling the operation of the activation unit 30. In some examples, the control circuitry forms part of the activation unit 30.

[0101] Each SMA can be selected from the group consisting of: a photoresponsive actuator, a dielectric or electrorestrictive elastomer actuator (DEA), a conductive polymer actuator (CP), an electroactive polymer actuator (EAP); and a magnetostrictive actuator (MA). The control circuitry can be arranged to control the intensity of the stimulus of the associated activation unit 30. Depending on the type of activation unit and associated SMA, the intensity of the stimulus can relate to the light of a photoresponsive SMA, the voltage level of a dielectric or electrorestrictive elastomer actuator (DEA), a conductive polymer actuator (CP) or an electroactive polymer actuator (EAP) or the magnetic flux of a magnetostrictive actuator (MA).

[0102] In some examples, the controller may deduce activation sequences based on sensor information accessed by the controller. For example, the sensor information may include strain sensor information from one or more strain sensors that sense movement and / or rotation of the body 102 and / or other components attached thereto. Alternatively or additionally, the sensor information may include accelerometer or gyroscope information from one or more accelerometers or gyroscopes attached to the body 102 and / or other components. Optionally, the sensor information may include electroencephalogram (EEG) or electromyography (EMG) information.

[0103] Based on sensor information, the controller can be configured to control (e.g., adjust or regulate) the intensity of the stimulus, the percentage or proportion of the stimulated SMA material, and the direction of change of the stimulated SMA material to generate a desired force or longitudinal distance displacement between the first anchorage zone and the second anchorage zone.

[0104] In some examples, the first anchorage area may be integrally formed with the support structure 101, and / or the second anchorage area may be integrally formed with the body 102.

[0105] Alternatively, the body 102 may include material fixedly attached thereto to the second anchorage zone.

[0106] The material can be fixedly or releasably attached to the body 102 and / or one or more SMAs.

[0107] Figure 2 Examples are given of (in its active state) Figure 1 The actuator assembly 100, i.e., in which at least one or more SMAs in the first SMA group have been activated. In this configuration, the position and / or orientation of the body 102 is configured to change relative to the support structure 101 due to the activation of at least one or more SMAs in the first SMA group. Since the connector unit 40 is attached to the body 102, it may also undergo the same or similar change in its relative position.

[0108] Figure 3 An actuator assembly 100 according to another example is shown, wherein the assembly 100 includes another (second) SMA group in its idle state. Figure 4 Examples are given of (in its active state) Figure 3the actuator assembly 100, i.e. where at least one or more of the SMAs of the first SMA group have been activated. In this configuration, the position and / or orientation of the body 102 is configured to change relative to the support structure 101 due to the activation of at least one or more of the SMAs of the first SMA group. Since the connector unit 40 is attached to the body 102, it can also experience the same or similar change in its relative position. Similarly, since the second SMA group is attached to the body 102, its configuration and / or position is also changed.

[0109] Each SMA of the sequence is directly attached to one or more SMAs. Alternatively or additionally, each SMA of the sequence can be directly attached to one or more anchoring regions, as shown with reference to Figure 3 and Figure 4 Each SMA can be directly attached at its first longitudinal end 21a', 21b' or second longitudinal end 21a", 21b" to one of the other SMAs or anchoring regions. In some examples, each SMA is directly attached to the next SMA and / or to the associated anchoring regions 11 and 12 in sequence using an adhesive or a seam.

[0110] However, in alternative examples, at least one of the SMAs can be attached to an adjacent SMA or anchoring region via a link, schematically shown as a solid line attaching the SMA to the respective anchoring region in Figure 18a and Figure 18b which in turn is directly attached to said SMA and the adjacent SMA or anchoring region. The link member forms part of the force transmission mechanism 20.

[0111] The number of links used can for example depend on the physical distance between the two connected anchoring regions in the idle state and the number and associated size of the SMAs connected in sequence between these anchoring regions. In turn, the number of SMAs can be selected based on the desired magnitude of the force generated between the anchoring regions when each SMA is activated. For example, reference is made to Figure 18a and Figure 18b showing six links 20a, 20b, 20c, and to Figures 1 to 15 showing a plurality of links.

[0112] The links of the force transmission mechanism can extend along or parallel to a longitudinal direction or axis (L) between the first and second anchoring regions along which the respective SMAs are connected in sequence. For this purpose, the links of the force transmission mechanism can be referred to as longitudinal links.

[0113] For example, consider an assembly with two connected anchor regions along a longitudinal direction or axis of 100 mm in the idle state and with four SMAs each of size 20 mm, then the resulting 20 mm of space in 100 mm (i.e. 100 mm - 4*20 mm = 20 mm) can be provided with one or more longitudinal links.

[0114] The force transmission mechanism is formed by the associated SMAs, their associated attachments to other SMAs or anchor regions, and any optional links.

[0115] The basic idea of the force transmission mechanism is to provide a minimum slack for each set of sequential SMAs connecting between associated anchor regions. In this way, a large portion of the force generated when activating the SMAs (e.g. up to 95%) can be transmitted from the associated SMAs to the anchor regions. In some examples, the force transmission mechanism has a force transmission efficiency of about 85% to about 95%. While a force transmission efficiency of 100% is ideal, in practice there is always a loss of efficiency due to poor deformation of the force transmission mechanism or adjacent materials connected thereto, resulting in an overall force transmission efficiency lower than the ideal value.

[0116] In some examples, the one or more links can comprise at least one of a fibre, a yarn, a cable, a wire, a film or a strip, having an elastic modulus δ = stress / strain, e.g. Young’s modulus, higher than a predetermined threshold.

[0117] The predetermined threshold can be set to be higher than the force generated by the associated SMA, thereby limiting the tendency of the link to deform along the longitudinal axis of the sequential connection of the first anchor region 11 and the second anchor region 12 along the SMA when the SMA is activated.

[0118] In one example, the one or more links are rigid, non-flexible or non-elastic. This allows the links to transmit the generated force along or parallel to the longitudinal direction when the associated SMA is activated.

[0119] The links can be strong enough to withstand the impact of the maximum composite force generation. On the other hand, the links can have a degree of flexibility along any non-longitudinal direction. For example, for this reason, cable-like links can be more popular than pushrod-like links.

[0120] The links can have a first end and a second end opposite the first end. The respective ends of the links can be arranged to be anchored to the anchor regions 11, 12, or to the longitudinal ends of one of the series of SMAs forming the SMA group. In some examples, the links are anchored using an adhesive or a mechanical attachment such as a seam.

[0121] In some examples, as referred to in the above examples, the SMA group can be arranged in a series of two or more SMAs connected in series along the longitudinal direction. Figures 18a to 18bAs shown, the force transmission mechanism 20 comprises at least one of: a first link 20a connected between and attached to a first anchor region and an SMA closest in sequence to the first anchor region 11; a second link 20b connected between and attached to two closest adjacent SMAs; and a third link 20c connected between and attached to a second anchor region and an SMA closest in sequence to the second anchor region.

[0122] In some examples, the force transmission mechanism can not comprise links, whereby each SMA 21a-21g of a sequence (in each set of SMAs) is directly attached to another SMA and an anchor region or two adjacent SMAs.

[0123] In alternative examples, the force transmission mechanism can be further connected to a damper or spring member arranged to dampen a reduction in longitudinal distance between the associated anchor regions 11, 12 upon activation of the associated SMA 21a-21g. The damper can comprise a tension spring (not shown) that smooths any sudden relative movement between the first and second anchor regions 11, 12, as referenced in Figures 11 to 12 In some examples, the spring can be arranged separately from the force transmission mechanism. Reference is made to Figure 7 and Figure 8 such configurations are shown. The spring member allows the associated further component fixed to the body via the respective anchor region to move smoothly upon activation of the associated SMA. For example, the damper can be attached in sequence between the first anchor region and the first SMA, as shown in Figure 11 and Figure 12 Accordingly, each SMA group can be connected to a damper arranged to dampen the force generated upon activation of the associated SMA, thereby smoothing any sudden reduction in longitudinal distance.

[0124] In some examples, the force transmission mechanism (20) of at least one of the SMA groups can further comprise a spring, damper or resilient member. These can be positioned in sequence between the respective first anchor region (11) and the respective second anchor region (12), for example, as shown in Figure 7 and Figure 8

[0125] In some examples, a sub-group of SMAs in each SMA group can be provided, which can be arranged to act as a spring. This can allow the sub-group of SMAs to contract upon activation of the respective SMA group or to extend upon deactivation of the respective SMA group. Possible examples are shown in Figure 9 and Figure 10 ​are pre-activated. This is illustrated in such examples by Figure 9 clearly showing where it is observed that the SMA sub-group in each SMA group is shorter than the rest of the respective SMA group. The SMA sub-group can be positioned at the bottom of the respective SMA group.

[0126] Furthermore, in such examples, when in the activated state, the rest or all of the first SMA group (i.e. the SMAs other than those belonging to the SMA sub-group) are activated, and the pre-activated SMA sub-group in the opposite SMA group is deactivated. This is illustrated in such examples by Figure 10 clearly showing where all or substantially all of the SMA in the SMA group on the left (i.e. the first group) are activated (i.e. they are shorter), and the pre-activated SMA sub-group in the opposite SMA group is deactivated (i.e. they are longer).

[0127] Referring to Figure 1 , Figure 15 and Figure 19 , the first sequential SMA group 21a-21g can be formed as a strip or 1D array of discrete SMAs. In some examples, the strip or array can comprise a film 51 (e.g. a thin film) that encapsulates the SMAs. In this way, the thin film forms one or more links of the force transmission mechanism. The thin film can be selected from materials configured to allow for conforming to the curvature of the body of the actuator assembly.

[0128] For example, the thin film can comprise a transparent coating or a plastic film applied over the SMA array, where the transparent coating or plastic film is arranged to transmit the actuation force through its structure.

[0129] Figure 18a An example is shown where the first sequentially connected SMA group 21a-21e is in its idle state (i.e. non-activated state). In the idle state, the longitudinal distance between the first anchor region 11 and the second anchor region 12 is denoted by D I When activated by an activation unit (not shown), the respective SMA 21a-21e mechanically contracts, which is illustrated in Figure 18b When there is no or a small external force compared to the external force resulting from the activation of the associated SMA, the force resulting from the mechanical contraction is transmitted to the respective anchor region since the SMA 21a-21e is physically connected to the anchor regions by the force transmission mechanism 20, and in this example via the plurality of links 20a-20c of the force transmission mechanism to the anchor regions. This in turn serves to pull the first anchor region 11 and the second anchor region 12 towards each other, whereby the longitudinal distance between the anchor regions in the activated state is reduced compared to the idle state. The resulting reduced longitudinal distance between the first anchor region 11 and the second anchor region 12 in the activated state is denoted by D Figure 18b A ​representations. From Figure 18a and Figure 18b It can be seen from A I However, when an external force is present, such as an external force acting in the opposite direction to the generated force and of the same magnitude as the generated force, the longitudinal distance can remain constant or substantially constant, as discussed above.

[0130] Reference is also made to Figures 1 to 12 and Figure 14 showing distances D I and D A Upon activation, the SMA mechanically contracts, which causes the length of the force transmission mechanism and the distance between the first and second anchor points to decrease by AD = D I - D A (comparing to Figure 18a and Figure 18b ). Thus, while the individual lengths of the links remain unchanged upon activation, the length of the force transmission mechanism decreases entirely due to the mechanical contraction of the SMA. The mechanical contraction generates a force pulling the first anchoring region 11 towards the second anchoring region 12 or pulling the second anchoring region 12 towards the first anchoring region 11.

[0131] To generate an increased force between the first and second anchoring regions 11, 12 of each SMA group, a second sequential SMA set 21a', 21b' (optionally formed as a second strip or a second ID array) can be connected to the first and second anchoring regions 11, 12 and laterally spaced apart from the first SMA set in the first SMA group.

[0132] In some examples, the second sequential SMA set can be arranged parallel to the first SMA group.

[0133] The second SMA set can also be sequentially connected between the first and second anchoring regions along a second direction different from the first direction or parallel to the first direction.

[0134] The second sequential SMA set can be laterally separated from the first SMA set. This means that any part of the second set is not attached to the first set, unless indirectly via the first and second anchoring regions. Lateral separation of the first set from the second set of each SMA group causes the force generated by each SMA group to act substantially only along the longitudinal direction in which the sequential SMAs are connected.

[0135] It can be said that the at least two laterally separated sequential SMA sets form a 2D array of laterally separated sequential SMAs.

[0136] ​In alternative examples, two or more SMA sets or SMA groups can be attached to each other laterally via lateral links to form a 2D array. The lateral links can allow the SMA sets to maintain a desired lateral spacing when activated in parallel. In this way, the lateral attachment can provide lateral stability to both groups when activated. This is especially advantageous when two or more sets are designed to be activated in parallel, as it allows for minimization of tilting or splaying of adjacent SMAs compared to when each group is activated while adjacent SMA groups are operating in an idle state.

[0137] It can be said that at least two laterally attached sequential SMA groups form a 2D array of laterally attached sequential SMAs.

[0138] Thus, depending on the application, the first SMA sets 21a-21g and one or more second SMA sets 21a'-21g' can be arranged in an array with other SMA sets laterally separated or laterally attached to another SMA set in the array.

[0139] In some examples, each SMA set in each group is arranged in parallel with other SMA sets in the same group, whereby respective SMAs in each group are sequentially connected along the same direction, such as a longitudinal direction (L) extending between the first and second anchor regions 11, 12.

[0140] In some examples, the second SMA sets 21a'-21g' in each group sequentially connected between the first and second anchor regions 11, 12 can be sequentially connected between the first and second anchor regions along a second direction (L'). The second direction of the second SMA groups can be different from the first direction of the first SMA sets.

[0141] In some examples, with reference to Figure 11 , the second SMA sets 21a'-21g' form in an array laterally separated or laterally attached comprising at least one further sequentially connected SMA set 21a''-21g'' arranged parallel to the second direction (L') and the first SMA sets 21a-21g are arranged along a first direction (L), wherein the first direction (L) is different from the second direction (L').

[0142] In some examples, a combination of laterally separated and laterally attached SMA arrays can be used.

[0143] In at least one example, the first set of SMAs further comprises at least a third set of SMAs having two further smart material actuators (SMAs) sequentially connected between the first anchor region and the second anchor region, wherein the third set of SMAs is sequentially connected between the first anchor region and the second anchor region along a third direction, wherein the third direction is different from the first direction or the second direction or parallel to the first direction or the second direction.

[0144] The first, second, or third set of SMAs in the first set of SMAs is formed in an array.

[0145] In at least one example, the first set of SMAs in the first set of SMAs is arranged in a first layer, and the second set of SMAs in the first set of SMAs is arranged in a second layer, wherein the second layer at least partially overlaps the first layer. The layers can be enclosed in a housing, for example.

[0146] The SMAs of each layer can be sequentially arranged along a set direction, which can be different from the direction of the sequential SMA arrangement of the adjacent layer. The layered arrangement of the SMAs can increase the density of the SMAs, enabling a greater force to be generated when more SMAs are activated simultaneously. Moreover, when the SMAs are layered arranged, wherein each layer comprises SMAs sequentially connected along a direction different from the direction of the sequential SMA arrangement of the adjacent layer, various types of forces can be generated in various directions. Thus, upon activation of the SMAs of each layer having SMAs sequentially connected along different directions, the body of the actuator assembly will be simultaneously pulled along different directions, thereby generating a force having a longitudinal component and a force having a transverse component, thereby generating a total torsional force.

[0147] In some examples, the respective anchor regions 11, 12 can be pivotably arranged to the respective support structure 101 or body 102.

[0148] The anchor regions can be fixed to the body 102, for example using elastic garters, belt ratchet type mechanisms (similar to those used for belt adjustment), Velcro and elastic bands, buttons and / or zip fasteners.

[0149] In one example, the at least one SMA is a light-responsive actuator. The activation unit 30 can comprise a light source for sending light to activate the at least one SMA.

[0150] The light-responsive actuator can be a photoactive polymer monomer, such as 2,4-dihydroxy-4-nitroazobenzene or 2,4-dihydroxy-4-azo-(4-nitroazobenzene) benzene. The present inventors have realized through various experiments that these photoactive polymer monomers provide a suitable specific intensity sufficient to extend to macroscopic scale actuation, enabling a fast response rate and / or safely isolating any electronic devices.

[0151] However, in alternative examples, the SMA can also be selected from the group consisting of dielectric or electro restriction elastomer actuators (DEA), conductive polymer actuators (CP), electro active polymer actuators (EAP) and magnetostrictive actuators (MA).

[0152] In some examples, the activation units 30 can be releasably or fixedly attached to the support structure. Having the activation units 30 arranged in a fixed relationship with the respective SMA can be advantageous for certain types of SMA, such as light responsive SMA, where the overall efficiency is improved when light is directed at each SMA from a certain angle and intensity. For example, Figures 5 to 12 and Figure 14 Portions of the activation units 30 that are arranged adjacent or in close proximity to the respective SMA groups are shown. In at least one example, these activation unit portions can be arranged to direct light at each SMA group.

[0153] For example, the activator units can be provided in locations that minimize the volume and disruption to movement.

[0154] In some examples, the arrangement of the activation units 30 is different from the support structure. For example, the activation units or at least portions thereof can be arranged remotely.

[0155] For examples where the smart material actuators are of the light responsive type, the activation units comprise a light source for sending light to activate each SMA.

[0156] In some examples, the activation units comprise a plurality of light sources provided in a configuration, such as an array corresponding to the array of SMA groups. For example, Figures 1 to 12 and Figure 14 The activation units 30 of each of the above can comprise a plurality of LED light strips, conforming to the shape of each SMA group. It will be appreciated that any number of LED light strips is possible. In some examples, the number of LED light strips is less than the number of SMA groups, whereby each LED light strip can be used to activate more than one SMA group.

[0157] The activation units 30 can further comprise a light guide (as shown by the arrows extending from the activation units 30) arranged to receive light from the light source and direct the received light at one or more SMA.

[0158] Using a light guide that is intrinsically flexible, the respective light guide can be arranged at a predetermined distance and in a predetermined orientation relative to the one or more SMA in the idle state.

[0159] In some examples, the light guide is physically separate from the respective sequential SMA group.

[0160] The activation units 30 can comprise a light emitting diode (LED) panel, such as a flexible LED panel.

[0161] In some configurations, the LED panel or flexible LED panel can include at least one LED for each SMA, with one or more LEDs of the LED panel having a spatial configuration corresponding to the spatial configuration of the associated SMA. However, in alternative examples, the spatial configuration of the LEDs of the LED panel can be different from the spatial configuration of the SMAs. Thus, a one-to-one spatial configuration match between each SMA and the respective LED of the LED panel can not be required. Rather, one or more LEDs in the LED panel that generally cover any associated SMA can be activated to activate the respective SMA, or the respective SMA can be activated to activate the one or more LEDs.

[0162] Alternatively, the activation unit can include one or more LEDs attached to a flexible printed circuit board (PCB) that are arranged in a position proximate to the associated light-responsive SMA.

[0163] The one or more LEDs or LED panel can be attached to the position of the associated SMA.

[0164] In some examples, the LEDs of the LED panel can be arranged to emit blue, ultraviolet, and / or green light. In some examples, the blue, ultraviolet, and / or green LEDs are alternated over the LED panel.

[0165] For the light-responsive actuators mentioned above, some wavelengths are particularly effective at causing a chiral change (i.e., a complex shape change). For example, depending on the type of light-responsive actuator, a shorter wavelength selected such as an ultraviolet (UV) wavelength (<400 nm) or a blue wavelength at the end of the visible spectrum can cause a mechanical contraction of the light-responsive actuator, while a longer wavelength such as a green wavelength (about 550 nm) can cause a mechanical expansion of the light-responsive actuator. Wavelengths between UV and green, such as the blue wavelength range (400 nm - 550 nm) can cause either a mechanical contraction or a mechanical expansion, depending on the SMA type selected. Light emitting these wavelengths can allow for fine-tuning of the mechanical contraction and / or expansion in terms of percentage contraction. The selection of the wavelength can also affect the response rate, as certain types of light-responsive SMAs are more sensitive to particular wavelengths. Further, certain wavelengths can be advantageous for causing a long-term shape change of the associated SMA, while other wavelengths only allow for a short-term shape change of the associated SMA after the activation unit using the wavelength to emit electromagnetic radiation is deactivated.

[0166] In at least one example, the activation unit 30 can be a light-emitting film or panel.

[0167] Alternatively, a thin film light source can be formed using electroluminescent paint that forms part of the activator unit, where the paint emits light when electrically stimulated by electrodes.

[0168] Alternatively or additionally, bioluminescence, where light is emitted by an organism, or chemiluminescence, where light is produced as a result of a chemical change / reaction, can also be used as a light source.

[0169] The electrical components of the actuator assembly 100 (e.g. the controller and activation unit) can be powered by a power pack. In some examples, the power pack is configured to be attached to the actuator assembly 100. The power pack can comprise one or more batteries, for example rechargeable batteries. Any conventional battery can be used, for example lithium-ion batteries or the like.

[0170] In some examples, the actuator assembly 100 further comprises a human-machine interface (HMI) connected to the controller, which allows a user or individual to interact with the controller. The HMI can comprise a power on / off function. Alternatively or additionally, the HMI interface can comprise a wireless communication interface, for example Bluetooth, WIFI or NFC, allowing control of the operation of the controller. For example, a smartphone application or PC, operably coupled to the wireless communication interface, can be used to adjust parameters such as range of motion and resistance.

[0171] The HMI can comprise physical or touch buttons to control various operating modes or functionalities of the controller. The HMI can further comprise a display unit, such as a touch screen, which allows information relating to the power status, battery life or optional biometric data collected from various biometric sensors, such as heart rate, steps, to be displayed. LED indicator lights can also be integrated into the HMI to indicate the power status (on / off) and the like.

[0172] The activation sequence can be programmed to follow certain exercise movements for rehabilitation purposes. Alternatively, the activation sequence can be programmed by a clinician or patient to fine-tune the biomechanical parameters to meet the needs of each patient to take the initiative. The activation sequence can also be programmed to assist the individual’s own movement, thereby assisting in weight lifting exercises and the like. For example, the controller can be programmed to allow adjustment of the amount of assistance required according to a scale such as between 0% and 100%, such as via a smartphone application connected to the wireless communication interface.

[0173] While the above examples are described with reference to an actuator assembly that can be used for gimbal and / or stabilizer units of further components, it will be appreciated that the actuator assembly can alternatively be adapted and designed for other similar and / or suitable applications.

[0174] In at least one example, such as shown with reference to Figure 3 and Figure 8 The actuator assembly further comprises a second smart material actuator (SMA) set 22 / 23 connected between the further first and second anchoring regions 1 1 b / 1 1 c, 12b / 12c.

[0175] The second smart material actuator set 22 can be arranged at least partially opposite the first set of first smart material actuators 21, thereby forming a first agonist-antagonist SMA pair 21, 22.

[0176] The further second anchor region 12b of the second SMA set 22 can be arranged opposite the second anchor region 12a of the first SMA set 21 with respect to the first bisecting axis of the body.

[0177] In at least one example, the actuator assembly further comprises a third smart material actuator (SMA) set 23 connected between the further first anchor region 11c and the further second anchor region 12c. The actuator assembly can further comprise a fourth smart material actuator (SMA) set 24 connected between the further first anchor region 11d and the further second anchor region 12d, wherein the third smart material actuator set 23 is arranged at least partially opposite the fourth set of first smart material actuators 24, thereby forming a second agonist-antagonist SMA pair 23, 24. Reference is made to Figure 13 This configuration is best shown.

[0178] The further second anchor region 12c of the third SMA set 23 can be arranged opposite the second anchor region 12d of the fourth SMA set 24 with respect to the first bisecting axis of the body.

[0179] In another example, the actuator assembly comprises a fifth smart material actuator (SMA) set 25 connected between a further first anchor region (11e) and a further second anchor region 12e. The actuator assembly can further comprise a sixth smart material actuator (SMA) set 26 connected between a further first anchor region 11f and a further second anchor region 12f, wherein the fifth smart material actuator set 25 is arranged at least partially opposite the sixth smart material actuator set 26, thereby forming a third agonist-antagonist SMA pair 25, 26. Reference is made to Figure 14 and Figure 15 This configuration is best shown.

[0180] The further second anchor region 12e of the fifth SMA set 25 can be arranged opposite the second anchor region 12f of the sixth SMA set 26 with respect to the second bisecting axis (central axis) of the body.

[0181] In at least one example, the second anchor region 12a of the first SMA set is arranged 180 degrees along the body perimeter from the second anchor region 12b of the second SMA set. Such a configuration is shown in Figures 9 to 15

[0182] ​The second anchorage zone 12c of the third SMA group is arranged 180 degrees away from the second anchorage zone 12d of the fourth SMA group along the perimeter of the main body. (Reference) Figure 13 and Figure 15 This configuration is probably best illustrated.

[0183] According to one example, the second anchorage zone 12a of the first SMA group is arranged 90 degrees away from the second anchorage zone 12c of the third SMA group along the periphery of the body, and the second anchorage zone 12b of the second SMA group is arranged 90 degrees away from the second anchorage zone 12d of the fourth SMA group along the periphery of the body. Such a configuration may be... Figure 13 and Figure 15 It is best shown in the middle.

[0184] In some examples, the third agonist-antagonist SMA pairs 25 and 26 are arranged substantially orthogonal to the first agonist-antagonist SMA pairs 21 and 22 and the second agonist-antagonist SMA pairs 23 and 24. (Reference) Figure 14 and Figure 15 This configuration is probably best illustrated.

[0185] A corresponding second anchorage zone can be arranged on the outer surface, offset from the second bisecting axis (central axis) of the main body, thereby allowing tangential pull. This configuration is... Figures 1 to 15 Each of them is shown in the table.

Claims

1. An actuator assembly, the actuator assembly comprising: Support structure; The main body, which is supported by the supporting structure; At least a first anchorage area, which is attached to the support structure; At least a second anchorage area, which is attached to the body; At least one first smart material actuator (SMA) is connected between the first anchorage area and the second anchorage area and forms a first SMA set in a first SMA group; A force transmission mechanism, which connects the first anchorage area to the second anchorage area and includes the first SMA assembly, Each SMA is configured to operate in an idle state and an activated state triggered by a non-mechanical stimulus that causes the associated SMA to contract mechanically; and Activation units are arranged to send the nonmechanical stimulus individually to each SMA in response to a defined activation sequence.

2. The actuator assembly of claim 1, wherein the first SMA group comprises two or more SMAs sequentially arranged between the first anchoring region and the second anchoring region.

3. The actuator assembly according to any one of the preceding claims, wherein the force transmission mechanism comprises one or more links, wherein each link comprises at least one of fiber, yarn, cable, wire, membrane or strip.

4. The actuator assembly of claim 3, wherein the one or more links are rigid, non-flexible, or inelastic.

5. The actuator assembly according to any one of the preceding claims, wherein the force transmission mechanism includes a first end anchored to the first anchorage region or the second anchorage region and a second end attached to at least one of the sequential SMAs.

6. The actuator assembly according to any one of claims 3 to 5, wherein the force transmission mechanism comprises at least one of the following: A first link is connected between the first anchorage area and the SMA that is closest to the first anchorage area in sequence, and is attached to the first anchorage area and the SMA; The second link connects between and is attached to the two closest adjacent SMAs; and The third link connects the second anchorage zone to the SMA that is closest to the second anchorage zone in sequence and is attached to both the second anchorage zone and the SMA.

7. The actuator assembly according to any one of the preceding claims, wherein the at least two SMAs connected in sequence form part of an SMA array comprising more than one group of laterally separated or laterally attached SMAs.

8. The actuator assembly according to any one of the preceding claims, wherein the SMA subgroups in each SMA group are arranged to act as springs to allow the subgroups to contract when the respective subgroup SMA is activated or to extend when the respective subgroup SMA is deactivated.

9. The actuator assembly according to any one of the preceding claims, wherein the associated force transmission mechanism of at least one of the SMA groups further comprises a spring, damper, or elastic member sequentially located between a respective first anchorage zone and a respective second anchorage zone.

10. The actuator assembly according to any one of the preceding claims, wherein each SMA is selected from the group consisting of: Photoresponsive actuator; Dielectric or electrically limited elastomer actuator (DEA); Conductive polymer actuator (CP); Electroactive polymer actuators (EAPs); and Magnetostrictive actuator (MA).

11. The actuator assembly according to claim 7 or any of its dependent claims, wherein the SMA array is provided as a thin-film array configured to conform to the curvature of the body.

12. The actuator assembly of claim 11, wherein the thin film comprises a transparent coating or plastic film applied over the SMA array, wherein the transparent coating or plastic film is arranged to transmit actuation force through its structure.

13. The actuator assembly according to any one of the preceding claims, wherein the first SMA assembly is sequentially connected between the first anchoring region and the second anchoring region along a first direction.

14. The actuator assembly of claim 13, wherein the first SMA group is formed in an array.

15. The actuator assembly of claim 13 or 14, wherein the first SMA group further comprises at least a third SMA set having two additional smart material actuators (SMAs) sequentially connected between the first anchorage region and the second anchorage region, wherein the third SMA set is sequentially connected between the first anchorage region and the second anchorage region along a third direction, wherein the third direction is different from the first direction or the second direction or is parallel to the first direction or the second direction.

16. The actuator assembly of claim 14 or 15, wherein the first SMA set, the second SMA set, or the third SMA set in the first SMA group are formed in an array.

17. The actuator assembly of claim 15 or 16, wherein the first SMA set in the first SMA group is arranged in a first layer, and the second SMA set in the first SMA group is arranged in a second layer, wherein the second layer at least partially overlaps with the first layer.

18. The actuator assembly according to any one of the preceding claims, wherein the activation unit is releasably or permanently attached to the support structure.

19. The actuator assembly according to any of the preceding claims, wherein at least one of the SMAs is a photoresponsive actuator, and wherein the activation unit includes a light source for emitting light to activate the at least one SMA.

20. The actuator assembly of claim 19, wherein the activation unit further comprises a light guide arranged to receive light from the light source and to guide the received light to the at least one associated SMA.

21. The actuator assembly of claim 19 or 20, wherein the activation unit comprises a light-emitting diode (LED) panel, the LED panel comprising at least one LED for each SMA, wherein one or more LEDs of the LED panel have a spatial configuration corresponding to the spatial configuration of the associated SMA.

22. The actuator assembly of any one of claims 19 to 21, wherein the activation unit comprises a flexible light-emitting diode (LED) panel, the flexible light-emitting diode (LED) panel comprising at least one LED for each SMA, wherein the one or more LEDs of the flexible LED panel have a spatial configuration corresponding to the spatial configuration of the associated SMA.

23. The actuator assembly according to any one of claims 19 to 22, wherein the activation unit comprises one or more LEDs attached to a flexible printed circuit board (PCB).

24. The actuator assembly according to any one of claims 19 to 23, wherein the activation unit comprises one or more LED groups, each LED group being arranged to activate one or more associated SMAs in a corresponding SMA group.

25. The actuator assembly according to any of the preceding claims, wherein the body is arranged to move relative to the support structure when at least one of the SMAs is activated or deactivated.

26. The actuator assembly according to any one of the preceding claims, the actuator assembly further comprising a connector unit (40) attached to the body (102) and arranged to connect to another component.

27. The actuator assembly of claim 26, wherein the additional component is selected from the group consisting of: electronic devices, electromechanical devices, mechanical devices, remote control devices, aerospace components, payloads, tools, robot components, and control surfaces.

28. The actuator assembly according to any one of the preceding claims, wherein the body has a spherical shape, a circular shape, or an elliptical shape.

29. The actuator assembly according to any one of the preceding claims, wherein the support structure includes a plurality of ball bearings supporting the body, thereby allowing the body to move or roll relative to the support structure.

30. The actuator assembly according to any one of claims 1 to 28, wherein the support structure includes a tapered portion, a hollow pyramidal portion, a cup-shaped portion, or a recessed portion, such as a ball bearing recess, for retaining the body, wherein the body has a shape corresponding to the shape of the recessed portion.

31. The actuator assembly according to any one of the preceding claims, the actuator assembly further comprising a second smart material actuator (SMA) group connected between a further first anchoring region and a further second anchoring region.

32. The actuator assembly of claim 31, wherein the second smart material actuator group is arranged at least partially opposite to the first group of first smart material actuators to form a first excitation-antagonistic SMA pair.

33. The actuator assembly of claim 32, wherein the additional second anchoring region of the second SMA group is arranged opposite to the second anchoring region of the first SMA group relative to the first bisecting axis of the body.

34. The actuator assembly according to any one of claims 31 to 33, the actuator assembly further comprising... A third Smart Material Actuator (SMA) assembly is connected between a further first anchorage zone and a further second anchorage zone; and A fourth set of smart material actuators (SMAs) is connected between another first anchorage region and another second anchorage region, wherein the third set of smart material actuators is arranged at least partially opposite to the fourth set of first smart material actuators, thereby forming a second excitation-antagonistic SMA pair.

35. The actuator assembly of claim 34, wherein the additional second anchorage region of the third SMA group is arranged opposite to the second anchorage region of the fourth SMA group relative to the first bisecting axis of the body.

36. The actuator assembly according to any one of claims 31 to 35, the actuator assembly further comprising... A fifth Smart Material Actuator (SMA) group, the fifth Smart Material Actuator (SMA) group being connected between another first anchorage zone and another second anchorage zone; and A sixth Smart Material Actuator (SMA) group is connected between another first anchorage region and another second anchorage region, wherein the fifth Smart Material Actuator group is arranged at least partially opposite to the sixth Smart Material Actuator group to form a third excitation-antagonism SMA pair.

37. The actuator assembly of claim 36, wherein the additional second anchorage region of the fifth SMA group is arranged opposite to the second anchorage region of the sixth SMA group relative to the second bisecting axis (central axis) of the body.

38. The actuator assembly of claim 32 or 33, wherein the second anchoring region of the first SMA group is arranged to be offset 180 degrees from the second anchoring region of the second SMA group along the periphery of the body.

39. The actuator assembly of claim 34 or 35, wherein the second anchoring region of the third SMA group is arranged to be offset by 180 degrees from the second anchoring region of the fourth SMA group along the periphery of the body.

40. The actuator assembly of claim 39, wherein... The second anchorage area of ​​the first SMA group is arranged to be offset by 90 degrees from the second anchorage area of ​​the third SMA group along the periphery of the body, and the second anchorage area of ​​the second SMA group is arranged to be offset by 90 degrees from the second anchorage area of ​​the fourth SMA group along the periphery of the body.

41. The actuator assembly of claim 34 or any of its dependent claims, wherein the third excitation-antagonistic SMA pair is arranged substantially orthogonal to the first excitation-antagonistic SMA pair and the second excitation-antagonistic SMA pair.

42. The actuator assembly according to any one of the preceding claims, wherein the respective second anchoring region is arranged on the outer surface, offset from the second bisecting axis (central axis) of the body, thereby allowing tangential pull.

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