Multi-scene mechanical feedback device and control method thereof

Abstract

The invention provides a multi-scene mechanical feedback device and a control method thereof, and belongs to the field of virtual reality. Comprising one or more sets of single-degree-of-freedom frames, and each single-degree-of-freedom frame is configured to be telescopic through a fixing piece and a connecting piece; one or more groups of shape memory alloy components, each group of degree-of-freedom frame is at least provided with one group of shape memory alloy components, and the shape memory alloy components are configured to control the expansion degree of the single-degree-of-freedom frame; and the temperature adjusting assembly is configured to adjust the hardness of the shape memory alloy assembly by controlling the temperature of the shape memory alloy assembly so as to adjust the conversion of the single-degree-of-freedom frame between the stretching state and the retracting state.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of virtual reality, and particularly relates to a multi-scene mechanical feedback device and a control method thereof. BACKGROUND

[0002] Virtual reality (VR) technology integrates computer graphics, sensing technology, and human-machine engineering, and other multidisciplinary advantages to build a realistic and immersive virtual world for users. After wearing a special head-mounted device, users can enter this virtual environment and experience a variety of adventure scenarios, such as mountain bike riding, deep-sea diving, and space exploration. The VR system uses head tracking technology to capture user head movements in real time and dynamically adjusts the virtual perspective. Many systems also combine full-body tracking to achieve natural interaction with the virtual environment through gestures and body movements. In addition, stereo sound technology simulates the propagation of sound in reality, allowing users to accurately determine the direction and distance of the sound source.

[0003] The application potential of virtual reality is huge. Initially, VR was mainly used in the entertainment field, such as video games and film production; with the continuous development of technology, its application has been widely expanded to education, medical, and other fields. In the field of education, VR provides an immersive learning experience for students, allowing them to virtually explore ancient Egyptian civilization or walk inside the human body; in the medical field, VR is not only used to treat anxiety and post-traumatic stress disorder, but also assists doctors in surgical simulation and training, significantly improving medical efficiency and safety.

[0004] However, existing VR systems generally only provide users with visual experiences, and users lack tactile or motion feedback experiences, which can make users in the virtual scene unable to have a sense of being there. How to provide a tactile or motion feedback device is a problem that needs to be solved. SUMMARY

[0005] In view of this, the present application provides a multi-scene mechanical feedback device and a control method thereof, aiming to solve the problem of mechanical feedback in the virtual scene and improve the user experience in the virtual scene.

[0006] In a first aspect, the present application provides a multi-scene mechanical feedback device, comprising: one or more groups of single-degree-of-freedom frames, each degree-of-freedom frame being configured to be telescopic through a fixing member and a connecting member; one or more groups of shape memory alloy components, each group of degree-of-freedom frames being equipped with at least one group of shape memory alloy components, the shape memory alloy components being configured to control the telescopic degree of the single-degree-of-freedom frame; a temperature adjusting component configured to adjust the soft and hard degree of the shape memory alloy component by controlling the temperature of the shape memory alloy component, so as to adjust the conversion of the single-degree-of-freedom frame between the telescopic and non-telescopic states.

[0007] Optionally, the single degree of freedom frame comprises: a first fixed member, on which a plurality of second fixed members are fixed; a first connecting member, hinged to the second fixed member, each second fixed member being equipped with at least two first connecting members; a second connecting member, in a quadrangular prism structure, the plurality of second connecting members being distributed in an array, each second connecting member being hinged to an adjacent second connecting member or first connecting member at an edge position.

[0008] Optionally, the shape memory alloy assembly comprises: a first coupling support, fixed to the second connecting member; a second coupling support, fixed to the second connecting member; a shape memory alloy, one end of which is hinged to the first coupling support and the other end of which is hinged to the second coupling support, the shape memory alloy being configured to be in a bent state when the single degree of freedom frame is at an extension limit.

[0009] Optionally, the first coupling support and the second coupling support are hinged to the shape memory alloy through a rotary hinge, which can be formed by a pin shaft assembly.

[0010] Optionally, the temperature adjusting assembly comprises: a heating member, configured to heat the shape memory alloy; a temperature measurement probe, configured to measure the surface temperature of the shape memory alloy; and a temperature controller, configured to control the heating member according to the temperature measured by the temperature measurement probe.

[0011] Optionally, the heating member is a polyimide heating film.

[0012] Optionally, when a plurality of shape memory alloy assemblies are included, the plurality of shape memory alloy assemblies are connected to different second connecting members.

[0013] Optionally, when a plurality of shape memory alloy assemblies are included, the plurality of shape memory alloy assemblies are arranged in sequence side by side.

[0014] Optionally, when a plurality of shape memory alloy assemblies are included, the heating member is controlled by the temperature controller to be in a power-on or power-off state, so as to control the plurality of shape memory alloy assemblies to be in an extended state or a retracted state, respectively.

[0015] In a second aspect, the present application provides a control method of a multi-scene mechanical feedback device, comprising: determining a virtual application scenario; determining a force-displacement curve according to the virtual application scenario; According to the force-displacement curve, each group of shape memory alloy components is controlled to be in the stretched state or the contracted state by the temperature adjusting assembly, so as to realize the force feedback in the virtual application scene.

[0016] The technical scheme provided by the application has the beneficial effects including: The application provides a mechanical feedback device, which realizes mechanical feedback in a virtual scene by arranging a single-degree-of-freedom frame, a memory alloy component and a temperature adjusting assembly. The single-degree-of-freedom frame is used to realize stretching and contracting movements in a single degree of freedom, and the memory alloy component and the temperature adjusting assembly are used to drive the single-degree-of-freedom frame. When the temperature adjusting assembly controls the memory alloy component to be in a soft state, the memory alloy component does not apply force to the single-degree-of-freedom frame, and the single-degree-of-freedom frame is contracted under the action of an external force (for example, an external force applied when a user steps on). When the temperature adjusting assembly controls the memory alloy component to be in a hard state, the memory alloy component applies force to the single-degree-of-freedom frame, and the force applied by the memory alloy component to the single-degree-of-freedom frame hinders the contraction of the single-degree-of-freedom frame under the action of an external force (for example, an external force applied when a user steps on). By controlling the soft and hard states of the memory alloy component, mechanical feedback of a user in a virtual scene is realized. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical scheme in the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are some embodiments of the application, and other drawings can be obtained by those skilled in the art without any creative effort on the basis of these drawings.

[0018] Figure 1 The structural schematic diagram of the multi-scene mechanical feedback device provided by an embodiment of the application.

[0019] Figure 2 The structural schematic diagram of the multi-scene mechanical feedback device provided by an embodiment of the application.

[0020] Figure 3 The structural schematic diagram of the temperature control assembly provided by an embodiment of the application.

[0021] Figure 4 The structural schematic diagram of the multi-scene mechanical feedback device provided by another embodiment of the application.

[0022] Figure 5 The control method flowchart of the multi-scene mechanical feedback device provided by an embodiment of the application.

[0023] The reference signs are as follows: 1: single degree of freedom frame; 11: fixing member; 111: first fixing member; 112: second fixing member; 12: connecting member; 121: first connecting member; 122: second connecting member; 2: shape memory alloy assembly; 21: first coupling support; 22: second coupling support; 23: shape memory alloy; 24: rotary hinge; 25: high-temperature-resistant heat insulation sleeve; 3: temperature adjusting assembly; 31: heating member; 32: temperature measuring probe; 33: temperature controller. DETAILED DESCRIPTION

[0024] To make the objectives, technical solutions and advantages of the present application clearer, the technical solutions in the present application will be described clearly and completely below with reference to the drawings in the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0025] Reference is made to Figures 1 to 4 The structural schematic diagram of the multi-scene mechanical feedback device provided by an embodiment of the present application is shown in the figure. It comprises: One or more groups of single degree of freedom frames 1, each degree of freedom frame being configured to be telescopic through the fixing member 11 and the connecting member 12; One or more groups of shape memory alloy assemblies 2, each group of degree of freedom frames 1 being equipped with at least one group of shape memory alloy assemblies 2, the shape memory alloy assembly 2 being configured to control the telescopic degree of the single degree of freedom frame 1; The temperature adjusting assembly 3 is configured to adjust the soft and hard degree of the shape memory alloy assembly 2 by controlling the temperature of the shape memory alloy assembly 2, so as to adjust the conversion of the single degree of freedom frame 1 between the telescopic and non-telescopic states.

[0026] In an example, the single degree of freedom frame 1 comprises: The first fixing member 111 has a plurality of second fixing members 112 fixed thereon; The first connecting member 121 is hinged to the second fixing member 112, and each second fixing member 112 is equipped with at least two first connecting members 121; The second connecting member 122 is in a quadrangular prism structure, and a plurality of second connecting members 122 are arranged in an array, each second connecting member 122 being hinged to the adjacent second connecting member 122 or the first connecting member 121 at the edge position.

[0027] In an example, when the single degree of freedom frame 1 moves, the upper and lower planes thereof remain parallel and present different heights.

[0028] In an example, the second connecting member 122 is a hollow quadrangular prism structure.

[0029] In an example, the shape memory alloy assembly 2 comprises: A first coupling support 21 fixed with the second connecting member 122; A second coupling support 22 fixed with the second connecting member 122; A shape memory alloy 23 hingedly connected at one end with the first coupling support 21 and at the other end with the second coupling support 22, the shape memory alloy 23 being configured to be in a bent state when the single degree of freedom frame 1 is at the extension limit.

[0030] In an example, the first coupling support 21 and the second coupling support 22 are hingedly connected with the shape memory alloy 23 through a rotary hinge 24, which can be formed by a pin shaft assembly.

[0031] In an example, the coupling supports are fixedly connected with the rotary hinge 24, which can be achieved by welding or 3D printing technology; the rotary hinge 24 can be assembled by a pin shaft or manufactured by a dual-material 3D printing technology to have a structure of flexible hinge and rigid support.

[0032] The shape memory alloy 23 is connected with the rotary hinge 24 and moves synchronously with the single degree of freedom frame 1. Since the rotary hinge 24 has the ability of free rotation, the shape memory alloy 23 can realize free rotation bending at the end points and avoid torsional deformation. The bending energy of the shape memory alloy 23 changes smoothly and periodically reciprocates, because its deformation always remains in the elastic range.

[0033] The shape memory alloy 23 is connected with the rotary hinge 23 through a high-temperature-resistant heat insulation sleeve 25.

[0034] In an example, the temperature adjusting assembly 3 comprises: A heating member 31 configured to heat the shape memory alloy 23; A temperature measurement probe 32 configured to measure the surface temperature of the shape memory alloy 23; and A temperature controller 33 configured to control the heating member 31 according to the temperature measured by the temperature measurement probe 32.

[0035] In an example, the heating member 31 is a polyimide heating film.

[0036] The heating element 31 and the temperature measuring probe 32 are respectively attached to the two side surfaces of the shape memory alloy 23, and are respectively responsible for heating and temperature monitoring. The heating element 31 and the temperature measuring probe 32 are connected to the temperature controller (PID constant temperature controller) 33, which controls the heating element 31 and the temperature measuring probe 32 after being powered on, ensures that the shape memory alloy 23 is heated to and stabilized above the transformation temperature, and keeps it in the high-temperature austenite phase state. The temperature measuring probe 32 monitors and feeds back the temperature of the shape memory alloy 23 in real time. When the PID constant temperature controller is powered off, the shape memory alloy 23 cools below the transformation temperature and returns to the low-temperature martensite phase. By controlling the on-off of the PID constant temperature controller, the shape memory alloy 23 can be freely switched between the hard state (austenite) and the soft state (martensite).

[0037] In an example, when a plurality of shape memory alloy assemblies 2 are included, the plurality of shape memory alloy assemblies 2 are connected to different second connecting members 122.

[0038] In an example, when a plurality of shape memory alloy assemblies 2 are included, the plurality of shape memory alloy assemblies 2 are arranged in sequence side by side.

[0039] In an example, when a plurality of shape memory alloy assemblies 2 are included, the heating element 31 is controlled by the temperature controller 33 to be in a powered-on or powered-off state, so as to control the plurality of shape memory alloy assemblies 2 to be in an extended state or a retracted state, respectively.

[0040] As shown in Figure 5 Four groups of single-degree-of-freedom frame and shape memory alloy coupled basic units are connected in parallel to construct a stepping type multi-scene virtual force feedback device. The four groups of parallel units include shape memory alloy assemblies SMA01, SMA02, SMA03 and SMA04, and the coupling supports of each group of shape memory alloy assemblies are designed differently, so the corresponding force feedback characteristics are also different. Through the parallel combination of the four groups of units, a unique force-displacement curve can be realized, and then 16 different force feedback scenes are realized. 4 Combined with 16 visual animation effects, users can experience 16 diversified virtual reality scenes to achieve a highly immersive and rich interactive experience.

[0041] The device takes a single degree of freedom frame-shape memory alloy coupling as a basic module, and generates programmable virtual force in various interactive scenes through multi-module parallel construction. The same hardware platform can be quickly reconfigured under circuit control, and users can quickly add, delete, splice and convert modules without interrupting the operation of the system. Compared with traditional wearable systems that only provide positive and negative stiffness or vibration haptics at the end of the finger, the invention extends the force distribution from the local to the whole body, and can realistically reproduce various mechanical experiences such as stepping and collision. This design significantly improves the immersion in the virtual reality (VR) environment and can freely switch between various application scenarios.

[0042] The proposed single degree of freedom frame and shape memory alloy coupling basic unit is laid on the virtual scene ground, and after the user wears the head-mounted device, the user can immerse in the exploration and adventure of various environments such as hard street ground, primitive forest muddy area, and north and south polar ice surface. The effective fusion of virtual images and real force feedback significantly improves the user's immersion and interaction experience. With the increase in the number of basic units, the number of force feedback modes increases exponentially (2 raised to the power of N), which not only meets the rich virtual scene requirements, but also significantly reduces the construction cost. The simple structure and easy assembly make it have good universality and wide application prospect, and can meet the diversified needs of multi-scene virtual force feedback.

[0043] Figure 5 The control method of the multi-scene mechanical feedback device provided by an embodiment of the present application. Comprise: S101, determine the virtual application scene.

[0044] S102, determine the force-displacement curve according to the virtual application scene.

[0045] S103, according to the force-displacement curve, control each group of shape memory alloy components to be in the stretched state or the contracted state through the temperature adjusting assembly, realize the force feedback in the virtual application scene.

[0046] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A multi-scenario mechanical feedback device, characterized in that: include: One or more sets of single-degree-of-freedom frames, each of which is configured to be telescopic via fixings and connectors; One or more sets of shape memory alloy components, each set of degree-of-freedom frames is equipped with at least one set of shape memory alloy components, and the shape memory alloy components are configured to control the degree of extension and contraction of the single-degree-of-freedom frame; The temperature regulating component is configured to adjust the hardness and softness of the shape memory alloy component by controlling the temperature of the shape memory alloy component, so as to adjust the conversion of the single degree of freedom frame between the extension and contraction states.

2. The multi-scenario mechanical feedback device according to claim 1, characterized in that: The single degree of freedom framework includes: a first fixing member, on which a plurality of second fixing members are fixed; a first connecting member hinged to the second fixing member, each second fixing member being equipped with at least two first connecting members; The second connecting member is a quadrangular prism structure, and a plurality of second connecting members are distributed in an array. Each second connecting member is hinged to an adjacent second connecting member or first connecting member at an edge position.

3. The multi-scenario mechanical feedback device according to claim 1, characterized in that: Shape memory alloy components include: A first coupling support is fixed to the second connecting member; A second coupling support is fixed to the second connecting member; The shape memory alloy has one end hinged to the first coupling support and the other end hinged to the second coupling support, and the shape memory alloy is configured to be in a bent state when the single degree of freedom frame is at the extension and contraction limit.

4. The multi-scenario mechanical feedback device according to claim 3, characterized in that: The first coupling support and the second coupling support are hinged to the shape memory alloy through a rotary hinge, and the rotary hinge can be formed by a pin assembly.

5. The multi-scenario mechanical feedback device according to claim 3, characterized in that: The temperature regulation components include: a heating element configured to heat the shape memory alloy; a temperature measurement probe configured to measure a surface temperature of the shape memory alloy; and The temperature controller is configured to control the heating element according to the temperature measured by the temperature measuring probe.

6. The multi-scenario mechanical feedback device according to claim 5, characterized in that: The heating element is a polyimide heating film.

7. The multi-scenario mechanical feedback device according to claim 2, characterized in that: When a plurality of shape memory alloy components are included, the plurality of shape memory alloy components are connected to different second connecting members.

8. The multi-scenario mechanical feedback device according to claim 1, characterized in that: When a plurality of groups of shape memory alloy components are included, the plurality of groups of shape memory alloy components are sequentially arranged side by side.

9. The multi-scenario mechanical feedback device according to claim 5, characterized in that: When multiple groups of shape memory alloy components are included, the temperature controller controls the heating element to be in an on or off state, so as to control the multiple groups of shape memory alloy components to be in an extended state or a contracted state respectively.

10. A control method for a multi-scenario mechanical feedback device, characterized in that: include: Determine virtual application scenarios; Determine the force-displacement curve based on the virtual application scenario; According to the force-displacement curve, each group of shape memory alloy components is controlled to be in an extended state or a contracted state through a temperature regulating component, thereby realizing force feedback in the virtual application scenario.

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