A virtual reality multi-modal haptic feedback control system and method based on SMA

Abstract

The application relates to the technical field of virtual reality human-computer interaction, and discloses a virtual reality multi-modal tactile feedback control system and method based on SMA, which comprises a VR host, a control system and an SMA tactile feedback device; the control system comprises a control module, a power supply module, a driving module and a crystal oscillator module; the signal ends of the power supply module, the driving module and the crystal oscillator module are connected with the signal end of the control module; the signal end of the VR host is connected with the signal end of the control module; the SMA tactile feedback device comprises a plurality of SMA modules, and the signal ends of the SMA modules are connected with the signal end of the driving module. The application realizes accurate on-off control and current regulation of the SMA module, reduces the deformation error of the SMA module, thereby meeting the real-time requirement of VR interaction, and improving the reliability and ease of use of the system.

Description

Technical Field

[0001] This invention relates to the field of virtual reality human-computer interaction technology, specifically to a virtual reality multimodal haptic feedback control system and method based on SMA. Background Technology

[0002] Virtual reality (VR) technology, as an interactive simulation technology that integrates multi-source information, can construct realistic virtual environments for users. Its core lies in achieving coordinated feedback from multiple senses, including vision, hearing, and touch. Among these, haptic feedback technology is a key support for enhancing the immersion and realism of the VR experience, directly determining the naturalness and credibility of the user's interaction with the virtual environment. With the widespread application of VR technology in fields such as gaming, healthcare, and training, users have placed higher demands on the richness, accuracy, and stability of haptic feedback, urgently requiring a haptic feedback solution that can provide multimodal, high-precision, and highly stable feedback.

[0003] Currently, haptic feedback technologies in the field of virtual reality are mainly divided into four categories: mechanical transmission, pneumatic / hydraulic actuation, electrostimulation, and shape memory alloy (SMA) actuation. Each type of technology has varying degrees of shortcomings and is difficult to meet the actual needs of current VR immersive interaction, as detailed below: (1) Mechanical transmission type: vibration or displacement feedback is generated through mechanical structures such as motors, gears, and eccentric wheels. Typical products include the vibration motor of VR controllers, but the structure is complex, the size is large, and the feedback mode is single (mostly vibration). (2) Pneumatic / hydraulic driven type: The air pump and hydraulic cylinder are used to control the expansion / contraction of the air bag to achieve tactile feedback. Although it can provide a certain pressure feedback, the response speed is slow and the pipeline layout is complicated, making it unsuitable for lightweight equipment. (3) Electrical stimulation: Microcurrents are applied to the skin through electrodes to simulate touch. It is low in cost, but the feedback is not realistic and long-term use may cause discomfort to users. (4) Traditional SMA driven: Some technologies use a single SMA wire or a simple array structure to control the deformation of SMA through direct power supply to achieve feedback. However, there are problems such as insufficient power supply stability, low control accuracy, and single feedback mode (only single displacement / force feedback). Moreover, it has not formed a multi-modal (different force, frequency and displacement combination) tactile feedback capability.

[0004] In summary, existing virtual reality haptic feedback technologies generally suffer from problems such as single feedback modality, low control precision, and insufficient power supply stability. Furthermore, the shortcomings of various technologies are mutually restrictive, making it difficult to simultaneously achieve immersion, accuracy, and comfort, and failing to meet the current demands of VR technology towards higher precision, multimodality, and lightweight design. Therefore, there is an urgent need to develop a virtual reality multimodal haptic feedback control system based on SMA (Sensitive Motion Assist) to address the aforementioned technical problems of existing technologies and promote the upgrading and application of VR haptic feedback technology. Summary of the Invention

[0005] In order to overcome the shortcomings of the existing technology, the present invention aims to provide a virtual reality multimodal haptic feedback control system and method based on SMA, so as to solve the technical problems of how to achieve precise on / off control and current regulation of SMA module and reduce the deformation error of SMA module.

[0006] This invention is achieved through the following technical solution: In a first aspect, the present invention provides a virtual reality multimodal haptic feedback control system based on SMA, including a VR host, a control system and an SMA haptic feedback device; The control system includes a control module, a power supply module, a drive module, and a crystal oscillator module; The signal terminals of the power supply module, drive module, and crystal oscillator module are all connected to the signal terminal of the control module. The signal terminal of the VR host is connected to the signal terminal of the control module; The SMA haptic feedback device includes several SMA modules, and the signal terminals of the several SMA modules are connected to the signal terminals of the drive module.

[0007] Specifically, the control system also includes a communication module and a reset module; The signal terminal of the reset module is connected to the signal terminal of the control module, wherein the reset module is used to provide a stable clock signal to the control module; The signal terminals of the communication module are connected to the signal terminals of the VR host and the control module, respectively, for bidirectional data transmission between the VR host and the control system.

[0008] Furthermore, the communication module includes a Bluetooth chip U4, and the reset module includes a switch SW1, a capacitor CF1, and a resistor RF1; the resistor RF1 and the capacitor CF1 are both connected to the switch SW1 and the control module.

[0009] Furthermore, the control system also includes an interaction module and a download module; The signal terminals of both the interaction module and the download module are connected to the signal terminal of the control module. The interaction module is used to debug or switch the working mode of the control system, and the download module is used to burn programs into the control system or debug the system.

[0010] Furthermore, the interaction module includes a first button circuit and a second button circuit. The first button circuit includes a resistor K1_R1, a capacitor K1_C1, a resistor K1_R2, and a switch K1. One end of the resistor K1_R1 is connected to one end of the capacitor K1_C1, one end of the resistor K1_R2, and the switch K1. The other end of the capacitor K1_C1 is connected to the switch K1. The other end of the resistor K1_R1 is grounded. The other end of the resistor K1_R2 is connected to the control module. The second button circuit includes a resistor K2_R1, a capacitor K2_C1, a resistor K2_R2, and a switch K2. One end of the resistor K2_R1 is connected to one end of the capacitor K2_C1, one end of the resistor K2_R2, and the switch K2. The other end of the capacitor K2_C1 is connected to the switch K2. The other end of the resistor K2_R1 is grounded. The other end of the resistor K2_R2 is connected to the control module.

[0011] Furthermore, the download module includes a JTAG download port, which is used for programming and debugging the control module.

[0012] Preferably, the power supply module includes a first power supply circuit and a second power supply circuit; The first power supply circuit is used to power the SMA haptic feedback device, wherein the first power supply circuit includes chip U5, battery BT1, capacitor CB1, capacitor CB2, capacitor C3, capacitor C4, switch SW3, resistor RB1, resistor RB2, resistor RB3 and resistor RB4. The anode of battery BT1 is connected to one end of capacitor CB1, one end of capacitor CB2, and chip U5. The cathode of battery BT1 is connected to the first end of switch SW3. The second end of switch SW3 is connected to the other end of capacitor CB1, the other end of capacitor CB2, one end of resistor RB1, one end of resistor RB4, and chip U5. The other ends of resistor RB1 and resistor RB4 are connected to chip U5. One end of resistor RB2 and one end of resistor RB3 are both connected to chip U5. One end of capacitor C3 and one end of capacitor C4 are connected to chip U5 and connected to multiple SMA modules. The other ends of capacitor C3 and capacitor C4 are both connected to resistor RB3 and grounded. The second power supply circuit is used to supply power to the control module, drive module and crystal oscillator module; wherein the second power supply circuit includes a USB conversion circuit, a switching circuit and a voltage regulator circuit; The USB conversion circuit includes chip U3, terminal USB2, capacitors CK_C1, CK_C2, CK_C3, CK_C4, and crystal oscillator CK_X1; One end of capacitor CK_C1 and capacitor CK_C2 are both connected to chip U3. One end of capacitor CK_C3 is connected to one end of crystal oscillator CK_X1 and chip U3. The other end of capacitor CK_C3 is connected to one end of capacitor CK_C4. The other end of capacitor CK_C4 is connected to crystal oscillator CK_X1 and chip U3. The other end of capacitor CK_C1 is connected to chip U3 and terminal USB2. The switching circuit includes a switch SW2, a TVS diode D1, and a fuse F1; One end of the switch SW2 is connected to the terminal USB2, and the other end of the switch SW2 is connected to the TVS diode D1 and the fuse F1. The voltage regulator circuit includes chip U2, capacitor C_WY1, capacitor C_WY2, capacitor C_WY3, capacitor C_WY4, resistor R_WY1, and diode LED_WY1; One end of capacitor C_WY1 and one end of capacitor C_WY2 are connected to chip U2 and fuse F1. One end of capacitor C_WY3 and one end of capacitor C_WY4 are connected to chip U2 and one end of resistor R_WY1. The other end of capacitor C_WY1 is connected to the other end of capacitor C_WY2, the other end of capacitor C_WY3, the other end of capacitor C_WY4, and the cathode of diode LED_WY1 and grounded. The other end of resistor R_WY1 is connected to the anode of diode LED_WY1.

[0013] Preferably, the control module includes a chip U1, several capacitors, an inductor, and several resistors; wherein the several capacitors, inductors, and resistors are all connected to the chip U1. The driving module includes multiple MOS transistors connected to chip U1. The gate of each MOS transistor is connected to pin PB1 of chip U1, the drain of each MOS transistor is connected to chip U5, and the source of each MOS transistor is connected to each SMA module.

[0014] Preferably, the crystal oscillator module includes a first crystal oscillator circuit and a second crystal oscillator circuit; The first crystal oscillator circuit includes crystal OSC1, capacitor OSC_1, and capacitor OSC_2; One end of capacitor OSC_1 is connected to one end of crystal oscillator OSC1 and is connected to the control module. The other end of capacitor OSC_2 is connected to one end of capacitor OSC_2 and grounded. The other end of capacitor OSC_2 is connected to the other end of crystal oscillator OSC1 and is connected to the control module. The second crystal oscillator circuit includes crystal OSC2, crystal OSC3, capacitor OSC4, and capacitor OSC5; One end of capacitor OSC4 is connected to one end of crystal oscillator OSC2 and one end of crystal oscillator OSC3 and is connected to the control module. The other end of capacitor OSC4 is connected to one end of capacitor OSC5 and grounded. The other end of capacitor OSC5 is connected to the other end of crystal oscillator OSC2 and the other end of crystal oscillator OSC3 and is connected to the control module.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention provides a virtual reality multimodal haptic feedback control system based on SMA (Sensitive Motion Assist). The connection relationships between the VR host, control system, and SMA haptic feedback device are clearly defined. The control system includes a control module, power supply module, drive module, and crystal oscillator module. The SMA haptic feedback device 300 is equipped with several SMA modules and connected to the drive module, forming a complete haptic feedback control architecture. This overall structural design achieves closed-loop linkage between VR host command transmission, control system signal processing and drive, and SMA module haptic feedback. It integrates the core concepts of precise PWM control and MOSFET constant current drive into the overall architecture, structurally solving the problems of inaccurate SMA module on / off control, inconvenient current adjustment, and large deformation errors in existing technologies. Furthermore, the use of multiple SMA modules provides a structural foundation for multimodal haptic feedback, effectively improving the shortcomings of existing VR haptic feedback technologies such as single feedback mode, low control accuracy, and low power supply stability. Overall, it enhances the system's reliability and ease of use, meeting the real-time requirements of VR interaction.

[0016] Furthermore, a communication module and a reset module are added to the control system. The reset module is connected to the control module and provides it with a stable clock signal, which effectively improves the stability of the control module's operation and avoids problems such as control command delays and errors caused by unstable clock signals, thus ensuring the accuracy of SMA module control. The communication module realizes bidirectional data transmission between the VR host and the control system. Compared with one-way transmission, it can ensure that the haptic commands of the VR host are accurately transmitted to the control module. At the same time, it facilitates the control module to send feedback information from the SMA haptic feedback device back to the VR host, realizing real-time interaction between commands and feedback, improving the system's response speed and interaction smoothness, and optimizing the system's reliability and ease of use.

[0017] Furthermore, the communication module includes a Bluetooth chip U4, which is adapted to the needs of lightweight VR devices, avoiding the complexity of wired communication circuits and ensuring the stability of data transmission. The reset module includes a switch SW1, a capacitor CF1, and a resistor RF1, with resistor RF1 and capacitor CF1 connected to switch SW1 and the control module. This specific circuit structure design is simple and low-cost, and can accurately provide a stable clock signal to the control module, avoiding the potential faults caused by the complex structure of the reset module. This further improves the stability of the control system and indirectly ensures the accuracy of SMA module control, reducing its deformation error.

[0018] Furthermore, an interaction module and a download module are set up in the control system, both of which are connected to the control module. The interaction module is used to debug or switch the working mode of the control system, allowing operators to flexibly adjust system parameters and switch working modes according to different VR application scenarios and different haptic feedback requirements, thereby improving the system's adaptability and flexibility. This facilitates optimization for the control requirements of different SMA modules and reduces deformation errors. The download module is used to program the control system or debug the system, facilitating future upgrades and maintenance of the system program, timely repair of vulnerabilities that occur during the control process, and ensuring long-term stable operation of the system. It also facilitates debugging of the control algorithm, improving the accuracy of SMA module on / off control and current regulation, and optimizing the system's reliability and ease of use.

[0019] Furthermore, the interactive module includes a first button circuit and a second button circuit, and defines the specific component composition and connection relationship of the two button circuits. The specific circuit structure design is simple and low-cost, and the button operation is convenient. Operators can quickly switch the control system's working mode and adjust parameters through the buttons without complicated operation procedures, which improves the ease of operation of the system, ensures the accuracy of SMA module on / off control and current regulation, and reduces deformation error.

[0020] Furthermore, the download module includes a JTAG download port, which enables rapid programming of the control module. This facilitates real-time system debugging by staff, allowing for timely identification and resolution of program vulnerabilities and control parameter deviations, optimizing the generation accuracy of PWM control signals, and ultimately improving the precision of SMA module on / off control and current regulation, while reducing deformation errors. In addition, the JTAG download port's versatility facilitates future system program upgrades and maintenance, enhancing the system's usability and scalability.

[0021] Furthermore, the power supply module is divided into a first power supply circuit and a second power supply circuit, realizing zoned control of the power supply. The first power supply circuit is dedicated to powering the SMA haptic feedback device, while the second power supply circuit is dedicated to powering the control module, drive module, and crystal oscillator module. This avoids the problem of mutual interference between power supplies of different components, improves power supply stability, and thus avoids problems such as inconsistent deformation of the SMA module and decreased control accuracy caused by power supply fluctuations. At the same time, the specific component composition and connection relationship of the first and second power supply circuits are defined. The first power supply circuit, through the combination of chip U5, battery BT1, and various capacitors and resistors, achieves stable power supply to the SMA module and can accurately adjust the power supply current to ensure the consistency of SMA module deformation. The second power supply circuit integrates USB conversion circuit, switching circuit, and voltage regulator circuit, which can realize USB power supply and ensure the stability of the power supply voltage through the voltage regulator circuit, avoiding the impact of voltage fluctuations on core components such as the control module and drive module.

[0022] Furthermore, the control module includes chip U1 and several capacitors, inductors, and resistors. All components are connected to chip U1, ensuring stable operation of the control module. Capacitors and inductors can filter interference signals, improve the generation and transmission accuracy of control commands, and ensure the accuracy of PWM control signals. The drive module includes multiple MOSFETs connected to chip U1, and defines the specific connection relationship between the gate, drain, and source of the MOSFETs. MOSFETs have the characteristics of fast switching speed, low on-resistance, and precise control, which can accurately respond to the PWM control signals sent by the control module, realize precise on / off control and current regulation of the SMA module, effectively reduce the deformation error of the SMA module, and provide a driving guarantee for multimodal haptic feedback, improving the haptic feedback effect and control reliability of the system.

[0023] Furthermore, the crystal oscillator module includes a first crystal oscillator circuit and a second crystal oscillator circuit, and the specific component composition and connection relationship of the two crystal oscillator circuits are defined. The dual crystal oscillator circuit design can provide the control module with a more stable and accurate clock signal, avoiding problems such as control command generation delay and insufficient PWM control signal accuracy caused by clock signal deviation. The reasonable combination of the two crystal oscillator circuits can be flexibly switched according to the system's working requirements, improving the stability and reliability of the crystal oscillator module. This ensures that the control module can accurately interpret the VR host's haptic commands and generate accurate PWM control signals, providing a guarantee for the precise on / off control and current regulation of the SMA module, effectively reducing the deformation error of the SMA module, and improving the overall control accuracy of the system.

[0024] This invention also provides a virtual reality multimodal haptic feedback control method based on SMA (Sensitive Motion Assist). After receiving haptic commands from the VR host, the control module parses the control parameters of multiple SMA modules and generates corresponding PWM control signals, ensuring precise matching between the control signals and the control requirements of the SMA modules. The drive module drives multiple SMA modules according to the PWM control signals and simultaneously transmits the haptic feedback information from the SMA haptic feedback devices back to the control module, forming a closed-loop control. The control module adjusts the PWM control signals based on the feedback information and detects the on / off state and power supply time of the SMA modules, enabling real-time correction of control deviations and ensuring accurate on / off control and current regulation of the SMA modules, effectively reducing deformation errors of the SMA modules. The entire method has a clear logical flow and compact steps, achieving a combination of precise PWM control and MOSFET constant current drive, meeting the real-time requirements of VR interaction. It effectively solves the problems of single feedback mode, low control accuracy, and low power supply stability in existing technologies, improving system reliability and ease of use. Furthermore, the realization of collaborative control of multiple SMA modules enriches the haptic feedback modes and enhances the immersion and realism of VR interaction. Attached Figure Description

[0025] Figure 1 This is a block diagram of the virtual reality multimodal haptic feedback control system in an embodiment of the present invention; Figure 2 This is a schematic diagram of the control principle of the virtual reality multimodal haptic feedback control system in an embodiment of the present invention; Figure 3 This is a circuit diagram of the control module in an embodiment of the present invention; Figure 4 This is a circuit diagram of the communication module in an embodiment of the present invention; Figure 5 This is a circuit diagram of the reset module in an embodiment of the present invention; Figure 6 This is a circuit diagram of the interaction module in an embodiment of the present invention; Figure 7 This is a circuit diagram of the download module in an embodiment of the present invention; Figure 8 This is a circuit diagram of the crystal oscillator module in an embodiment of the present invention; Figure 9 This is a circuit diagram of the first power supply circuit in an embodiment of the present invention; Figure 10 This is a circuit diagram of the USB conversion circuit in an embodiment of the present invention; Figure 11 This is a circuit diagram of the switching circuit in an embodiment of the present invention; Figure 12 This is a circuit diagram of the voltage regulator circuit in an embodiment of the present invention; Figure 13This is a circuit diagram of the indicator circuit in an embodiment of the present invention; Figure 14 This is a circuit diagram of the startup circuit in an embodiment of the present invention; Figure 15 This is a circuit diagram of the driving module in an embodiment of the present invention; In the diagram: 100 is the VR host; 200 is the control system; 220 is the control module; 230 is the power supply module; 240 is the drive module; 250 is the crystal oscillator module; 260 is the communication module; 270 is the reset module; 280 is the interaction module; 290 is the download module; and 300 is the SMA haptic feedback device. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0027] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0028] The purpose of this invention is to provide a virtual reality multimodal haptic feedback control system and method based on SMA, which combines precise PWM control with constant current drive of MOSFET to achieve precise on / off control and current regulation of SMA module, reduce deformation error of SMA module, and thus meet the real-time requirements of VR interaction.

[0029] The present invention will now be described in further detail with reference to the accompanying drawings: See Figure 1 and Figure 2In one embodiment of the present invention, a virtual reality multimodal haptic feedback control system based on SMA is provided, including a VR host 100, a control system 200, and an SMA haptic feedback device 300; the control system 200 includes a control module 220, a power supply module 230, a drive module 240, and a crystal oscillator module 250; the signal terminals of the power supply module 230, the drive module 240, and the crystal oscillator module 250 are all connected to the signal terminals of the control module 220; the power supply module 230 is used to supply power to each unit or module in the circuit; the signal terminal of the VR host 100 is connected to the signal terminal of the control module 220; the SMA haptic feedback device 300 includes a plurality of SMA modules (not shown), and the signal terminals of the plurality of SMA modules are connected to the signal terminals of the drive module 240.

[0030] Specifically, the control system 200 also includes a communication module 260 and a reset module 270; the signal terminal of the reset module 270 is connected to the signal terminal of the control module 220, wherein the reset module 270 is used to provide a stable clock signal to the control module 220; the signal terminal of the communication module 260 is connected to the signal terminals of the VR host 100 and the control module 220 respectively, and is used for bidirectional data transmission between the VR host 100 and the control system 200.

[0031] The communication module 260 includes a Bluetooth chip U4, and the reset module 270 includes a switch SW1, a capacitor CF1, and a resistor RF1; the resistor RF1 and the capacitor CF1 are both connected to the switch SW1 and the control module 220, as shown below. Figure 4 and Figure 5 As shown.

[0032] Specifically, the control system 200 also includes an interaction module 280 and a download module 290; the signal terminals of both the interaction module 280 and the download module 290 are connected to the signal terminal of the control module 220, wherein the interaction module 280 is used to debug or switch the working mode of the control system 200, wherein the working mode includes at least one of the power supply state, communication state or SMA module working state of the control system 200; the download module 290 is used to program or debug the control system 200.

[0033] Among them, according to Figure 6As shown, the interaction module 280 includes a first button circuit and a second button circuit. The first button circuit includes a resistor K1_R1, a capacitor K1_C1, a resistor K1_R2, and a switch K1. One end of the resistor K1_R1 is connected to one end of the capacitor K1_C1, one end of the resistor K1_R2, and the switch K1. The other end of the capacitor K1_C1 is connected to the switch K1. The other end of the resistor K1_R1 is grounded. The other end of the resistor K1_R2 is connected to the control module. The second button circuit includes a resistor K2_R1, a capacitor K2_C1, a resistor K2_R2, and a switch K2. One end of the resistor K2_R1 is connected to one end of the capacitor K2_C1, one end of the resistor K2_R2, and the switch K2. The other end of the capacitor K2_C1 is connected to the switch K2. The other end of the resistor K2_R1 is grounded. The other end of the resistor K2_R2 is connected to the control module.

[0034] Among them, according to Figure 7 As shown, the download module 290 includes a JTAG download port, which is used for programming and debugging the control module.

[0035] In this embodiment, the download module includes resistors RJ1, RJ2, RJ3, RJ4, and RJ5, and terminal P1. One end of resistor RJ4 is connected to pin 9 of terminal P1 and the TCK pin of chip U1, and the other end of resistor RJ4 is grounded. One end of resistor RJ1, one end of resistor RJ2, and one end of resistor RJ3 are connected to terminal P1 and connected to the power input terminal 3V3. The other end of resistor RJ3 is connected to pin 7 of terminal P1 and the TMS pin of chip U1. The other end of resistor RJ2 is connected to pin 5 of terminal P1 and the TDI pin of chip U1. The other end of resistor RJ1 is connected to pin 3 of terminal P1 and the NTRST pin of chip U1. One end of resistor RJ5 is connected to pin 13 of terminal P1 and the TDO pin of chip U1, and the other end of resistor RJ5 is connected to the power input terminal 3V3. The drive module includes terminal H8, multiple MOSFET modules and terminal H9. There are 9 MOSFET modules. Each MOSFET module is connected to each SMA module. Each MOSFET module includes a resistor, a MOSFET and a TVS diode. Each MOSFET module is connected to terminal H8 and terminal H9. Terminal H9 is connected to chip U1.

[0036] Specifically, the power supply module 230 includes a first power supply circuit and a second power supply circuit; the first power supply circuit is used to power the SMA haptic feedback device 300, wherein, for example... Figure 9As shown, the first power supply circuit includes chip U5, battery BT1, capacitors CB1, CB2, C3, and C4, switch SW3, resistors RB1, RB2, RB3, and RB4. The anode of battery BT1 is connected to one end of capacitor CB1, one end of capacitor CB2, and chip U5. The cathode of battery BT1 is connected to the first end of switch SW3. The second end of switch SW3 is connected to the other end of capacitor CB1, the other end of capacitor CB2, one end of resistor RB1, one end of resistor RB4, and chip U5. The other ends of resistors RB1 and RB4 are connected to chip U5. One end of resistor RB2 and one end of resistor RB3 are both connected to chip U5. One end of capacitor C3 and one end of capacitor C4 are connected to chip U5 and connected to multiple SMA modules. The other ends of capacitors C3 and C4 are both connected to resistor RB3 and grounded. The second power supply circuit is used to supply power to the control module 220, the drive module 240, and the crystal oscillator module 250; wherein the second power supply circuit includes a USB conversion circuit, a switching circuit, and a voltage regulator circuit; the USB conversion circuit includes a chip U3, a USB terminal 2, capacitors CK_C1, CK_C2, CK_C3, CK_C4, and a crystal oscillator CK_X1; one end of capacitor CK_C1 and capacitor CK_C2 are both connected to chip U3, one end of capacitor CK_C3 is connected to one end of crystal oscillator CK_X1 and then to chip U3, the other end of capacitor CK_C3 is connected to one end of capacitor CK_C4, the other end of capacitor CK_C4 is connected to crystal oscillator CK_X1 and chip U3, and the other end of capacitor CK_C1 is connected to chip U3 and USB terminal 2, as shown below. Figure 10 As shown; the switching circuit includes switch SW2, TVS diode D1, and fuse F1; one end of switch SW2 is connected to terminal USB2, and the other end of switch SW2 is connected to TVS diode D1 and fuse F1, as shown. Figure 11 As shown; the voltage regulator circuit includes chip U2, capacitors C_WY1, C_WY2, C_WY3, and C_WY4, resistor R_WY1, and diode LED_WY1; one end of capacitor C_WY1 and one end of capacitor C_WY2 are connected to chip U2 and fuse F1; one end of capacitor C_WY3 and one end of capacitor C_WY4 are connected to chip U2 and one end of resistor R_WY1; the other end of capacitor C_WY1 is connected to the other ends of capacitors C_WY2, C_WY3, and C_WY4, and the cathode of diode LED_WY1 and grounded; the other end of resistor R_WY1 is connected to the anode of diode LED_WY1, as shown. Figure 12 As shown.

[0037] In this embodiment, battery BT1 outputs 3V voltage and 1.5A current. The positive terminal of battery BT1 is connected to the drain (D) terminal of the MOSFET, providing operating current for the SMA haptic feedback device. The voltage regulator chip U2 in the voltage regulator circuit is an AMS1117-3.3V regulator chip. The output from battery BT1 is converted to 3V3 voltage by the regulator chip U2 to power peripherals such as the microcontroller, Bluetooth, and LEDs. Filter capacitors are connected in parallel at the input / output terminals and key circuit nodes of the regulator chip to filter out ripple. The power supply module provides stable and matched power (voltage) to all modules of the system. The SMA haptic feedback device uses a 3V constant current power supply, while peripherals use a 3V3 regulated power supply. The drive module mainly includes multiple parallel MOSFETs. The gate (G) terminal of the MOSFET is connected to the PB1 pin of chip U1 to receive (PWM) control signals. The drain (D) terminal of the MOSFET is connected to the battery's B3V pin, and the source (S) terminal of the MOSFET is connected to the SMA haptic feedback device. The power input terminal of the MOSFET is connected to a 3V3 power supply. The communication module includes a USB interface (terminal USB2), Bluetooth (module), and RS232 serial port. The USB interface enables wired communication with the PC / VR host and provides power backup. Bluetooth connects to chip U1 via the serial port to achieve wireless data transmission. The RS232 serial port is used for serial communication expansion. The communication module enables bidirectional data transmission between the VR host and the control system, receives tactile commands (such as force, frequency, and duration), and provides feedback on the system's operating status.

[0038] Specifically, according to Figure 3 As shown, the control module 220 includes a chip U1, several capacitors, inductors, and several resistors; wherein the capacitors, inductors, and resistors are all connected to the chip U1; the drive module 240 includes multiple MOSFETs connected to the chip U1, the gate of each MOSFET is connected to the PB1 pin of the chip U1, the drain of each MOSFET is connected to the chip U5, and the source of each MOSFET is connected to each SMA module accordingly, as shown. Figure 15 As shown.

[0039] In this embodiment, the control module 220 includes a microcontroller U1 (model STM32F103VET6). Chip U1 is connected to the power supply module 230 via a 3V3 pin to obtain stable power (voltage). Chip U1 is connected to the drive module 240 via a PB1 pin to output PWM control signals. Chip U1 is connected to the communication module (USB / Bluetooth) via an RS232 interface and a USB pin to achieve data transmission. Chip U1 is connected to the interaction module 280 via pins PC0-PC3, PC6, and PD2. Chip U1 is connected to the reset module and crystal oscillator module 250 via corresponding dedicated pins to ensure stable operation. The interaction module 280 includes a first button circuit, a second button circuit, and an indicator circuit. Figure 13As shown, the indicator circuit includes resistors RGB_G1, RGB_R1, and RGB_B1, and diode group RGB1. One end of resistor RGB_G1 is connected to pin PB0 of chip U1, and the other end is connected to the cathode of diode G (green light) in diode group RGB1. One end of resistor RGB_R1 is connected to pin PB5 of chip U1, and the other end is connected to the cathode of diode R (red light) in diode group RGB1. One end of resistor RGB_B1 is connected to pin PB1 of chip U1, and the other end is connected to diode B (blue light) in diode group RGB1. The anode of diode R is connected to the anodes of diode G and diode B. Additionally, the control system 200 also includes a startup circuit connected to control module 220, according to... Figure 14 As shown, the startup circuit includes resistors RBO1 and RBO2. One end of resistor RBO1 is connected to the BOOT0 pin of chip U1, and one end of resistor RBO2 is connected to the BOOT1 pin of chip U1. The other ends of resistors RBO1 and RBO2 are connected to ground. The control module receives haptic commands from the VR host, analyzes them, and outputs precise control signals to drive the SMA haptic feedback device 300, while also providing feedback on the system's operating status.

[0040] In this embodiment, the SMA haptic feedback device 300 employs an array structure composed of multiple shape memory alloy wires (or sheets). Each SMA module corresponds to a MOSFET driving channel (expandable to a multi-channel design). One end of the SMA module is fixed to a VR interaction device (such as the knuckles or handle contact surface of a VR glove), and the other end is connected to an elastic reset structure. When the SMA module is powered on, it deforms (contracts or bends), generating a force. After power is cut off, it returns to its initial state under the action of the elastic reset structure, thereby achieving haptic feedback. By setting up a VR host 100, a control system 200, and an SMA haptic feedback device 300, the control system 200 includes a control module 220, a power supply module 230, a drive module 240, and a crystal oscillator module 250. The SMA haptic feedback device 300 includes multiple SMA modules connected to the drive module 240. The control module 220 receives haptic commands from the VR host 100, parses the control parameters of the multiple SMA modules, and generates PWM control signals. The drive module 240 drives the multiple SMA modules according to the PWM control signals and sends haptic feedback information to the control module 220. The control module 220 adjusts the PWM control signals according to the haptic feedback information and detects the status information of the SMA modules. By combining precise PWM control with constant current drive of MOSFETs, precise on / off control and current regulation of the SMA modules are achieved, reducing the deformation error of the SMA modules. This meets the real-time requirements of VR interaction and effectively solves the problems of single feedback mode, low control accuracy, and low power supply stability in existing virtual reality haptic feedback technologies, thereby improving the reliability and ease of use of the system.

[0041] Specifically, according to Figure 8 As shown, the crystal oscillator module 250 includes a first crystal oscillator circuit and a second crystal oscillator circuit; the first crystal oscillator circuit includes crystal OSC1, capacitor OSC_1, and capacitor OSC_2; one end of capacitor OSC_1 is connected to one end of crystal OSC1 and is connected to the control module 220, the other end of capacitor OSC_2 is connected to one end of capacitor OSC_2 and grounded, and the other end of capacitor OSC_2 is connected to the other end of crystal OSC1 and is connected to the control module 220; the second crystal oscillator circuit includes crystal OSC2, crystal OSC3, capacitor OSC4, and capacitor OSC5; one end of capacitor OSC4 is connected to one end of crystal OSC2 and one end of crystal OSC3 and is connected to the control module 220, the other end of capacitor OSC4 is connected to one end of capacitor OSC5 and grounded, and the other end of capacitor OSC5 is connected to the other end of crystal OSC2 and the other end of crystal OSC3 and is connected to the control module 220.

[0042] In this embodiment, crystal oscillators OSC2 and OSC3 are connected to the PC14-OSC32K_IN and PC15-OSC32K_OUT pins of chip U1, respectively. Capacitors OSC_1, OSC_2, OSC4, and OSC5 are all matching capacitors (100nF). The crystal oscillator segments are connected to the PC14 and PC15 pins of chip U1, respectively. The matching capacitors are connected in parallel between the crystal oscillator and GND. The crystal oscillator module provides a stable clock signal to chip U1 to ensure the timing accuracy of control commands. The output of the reset module is connected to the NRST pin of chip U1, and the power input of the reset module is connected to a 3V3 voltage. The reset module can realize the reset function in case of system abnormality to ensure stable system operation. The interactive module includes two buttons (a first button circuit and a second button circuit) and an LED indicator. The first button circuit and the second button circuit are connected to the PC2 and PC1 pins of chip U1, respectively. One end of each button is connected to 3V3, and the other end is connected to the PC2 and PC1 pins of chip U1 (level detection is achieved through pull-up resistors). The LED indicator (LED_WY1) is model SZYY0603G1. The anode of the LED is connected to 3V3 through a current-limiting resistor, and the cathode is connected to the GPIO pin of chip U1. The buttons of the interactive module are used for manual debugging and mode switching, while the LEDs are used to indicate the system power supply status, communication status, and SMA working status. The download module includes a PZ254V-12-10P (pin header) JTAG download interface. The JTAG download interface is connected to the TD1, TMS, TCK, TDO, and NRST debugging pins of chip U1, and is used for program burning and system debugging.

[0043] In summary, this embodiment provides a virtual reality multimodal haptic feedback control system based on SMA (Sensitive Motion Assist). The connection relationships between the VR host, control system, and SMA haptic feedback device are clearly defined. The control system includes a control module, power supply module, drive module, and crystal oscillator module. The SMA haptic feedback device 300 is equipped with several SMA modules and connected to the drive module, forming a complete haptic feedback control architecture. This overall structural design achieves closed-loop linkage between VR host command transmission, control system signal processing and drive, and SMA module haptic feedback. It integrates the core concepts of precise PWM control and MOSFET constant current drive into the overall architecture, structurally solving the problems of inaccurate SMA module on / off control, inconvenient current adjustment, and large deformation errors in existing technologies. Furthermore, the use of multiple SMA modules provides a structural foundation for multimodal haptic feedback, effectively improving the shortcomings of existing VR haptic feedback technologies, such as single feedback mode, low control accuracy, and low power supply stability. Overall, it enhances the system's reliability and ease of use, meeting the real-time requirements of VR interaction.

[0044] Example 2 This embodiment also provides a virtual reality multimodal haptic feedback control method based on SMA. The virtual reality multimodal haptic feedback control system based on SMA, as described above, includes the following process: After receiving the haptic commands from the VR host 100, the control module 220 parses the control parameters of multiple SMA modules and generates PWM control signals corresponding to the control parameters. Control module 220 sends a PWM control signal to drive module 240. Drive module 240 drives multiple SMA modules according to the PWM control signal and sends haptic feedback information from SMA haptic feedback device 300 to control module 220. The control module 220 adjusts the PWM control signal according to the haptic feedback information to detect the status information of multiple SMA modules, thereby completing virtual reality multimodal haptic feedback control. The status information includes on / off status and power supply time.

[0045] The specific execution process is as follows: (1) Data transmission: The VR host 100 generates multimodal tactile commands (including parameters such as force level, feedback frequency, and duration) based on tactile events (such as touching objects, collisions, grabbing, etc.) in the virtual scene, and transmits them to the STM32F103VET6 microcontroller via USB or Bluetooth module. (2) Instruction parsing: After receiving the instruction, the STM32 microcontroller (chip U1) parses the control parameters of each SMA module and generates the corresponding PWM control signal according to the parameters; (3) Drive control: The PWM control signal is output to the gate of the MOSFET module (MOS transistor) to control the on / off state of the MOSFET; when on, the 3V battery provides a constant current to the SMA module, the SMA module undergoes a preset deformation and generates tactile feedback; by adjusting the duty cycle (controlling the current) and frequency (controlling the on / off rhythm) of the PWM signal, tactile feedback of different strengths and frequencies can be achieved. (4) Status feedback: The microcontroller detects the working status of the SMA module in real time (through the current detection circuit or feedback pin) and transmits the status information (such as whether it is working normally or whether the power supply is stable) back to the VR host through the communication module. At the same time, the system operating status is indicated by LED lights. (5) Multimodal implementation: By controlling the collaborative work of multiple SMA modules (starting order, force combination, frequency difference of different units), a variety of tactile modalities are simulated, such as the pressing feedback of soft materials, the texture of rough surfaces, and the dynamic impact feedback.

[0046] In this embodiment, the multimodal feedback design can simulate tactile information from various real-world scenarios, such as the hardness of different materials, dynamic force changes, and texture, significantly enhancing the immersion and interactive experience of VR users. The precise PWM control of the STM32 microcontroller combined with the constant current drive of the MOSFET ensures that the deformation error of the SMA module is controlled within ±5%, and the response latency is ≤10ms, meeting the real-time requirements of VR interaction. The modular circuit design reduces the system size by more than 30% and the weight by 25%, allowing direct integration into lightweight devices such as VR gloves and controllers, solving the problems of bulky and difficult-to-integrate structures in existing technologies. The dedicated power supply module and filtering design ensure stable operating voltage / current of the SMA haptic feedback device, extending its lifespan (cycle count ≥10,000 times). The status feedback and reset mechanism reduce the probability of system failure and improve long-term operational reliability. The standardized interface and multi-channel drive design support the expansion of the number of SMA haptic units (SMA modules) (from single channel to 9 channels), adapting to the needs of VR interaction scenarios with varying complexity. In other words, by combining the SMA array structure with multi-channel MOSFET driving, multimodal tactile feedback combining force, frequency, and displacement can be achieved, breaking through the limitations of the single feedback mode in existing technologies and improving the realism of tactile feedback. Using the STM32F103VET6 microcontroller as the core controller (control module), along with the AMS1117-3.3V voltage regulator circuit and MOSFET constant current drive design, the problems of low control accuracy and unstable power supply in existing SMA driving technologies are solved, ensuring the consistency of SMA deformation and real-time response. The circuit adopts a modular layout, with standardized pin headers and USB interfaces, featuring small size and light weight, allowing for flexible integration into lightweight devices such as VR gloves and controllers, offering strong adaptability and easy expansion and maintenance. An interactive module consisting of buttons and LED indicators supports manual debugging and mode switching, while a status feedback mechanism enables system fault self-detection, improving system reliability and ease of use.

[0047] The STM32F103VET6 can be replaced with other models in the STM32F103 series (such as STM32F103RCT6, STM32F103C8T6) or ESP32 series microcontrollers. As long as they have PWM output, serial communication functions, and matching pin counts, the same control effect can be achieved. The 3V battery can be replaced with two 1.5V dry batteries in series or a 3.7V lithium battery (with a DC-DC step-down module to output a constant 3V voltage). As long as a stable 3V and a current of 1.5A or higher can be provided, the SMA haptic feedback device can operate normally. The Bluetooth module can... The VR host and controller can be replaced with a WiFi module (such as ESP8266) or a 2.4G wireless module. The USB interface can be replaced with a Type-C interface. As long as bidirectional data transmission between the VR host and the controller can be achieved, it can be used. The shape memory alloy wire can be replaced with a shape memory alloy sheet or an SMA spring. As long as it can generate a preset force and displacement through energized deformation, the same tactile feedback effect can be achieved. The MOSFET module can be replaced with a relay module or a dedicated SMA driver chip (such as DRV8833). As long as precise on / off control and current regulation can be achieved, the same driving effect can be achieved.

[0048] In summary, this embodiment provides a virtual reality multimodal haptic feedback control method based on SMA. After receiving haptic commands from the VR host, the control module parses the control parameters of multiple SMA modules and generates corresponding PWM control signals, ensuring precise matching between the control signals and the control requirements of the SMA modules. The drive module drives multiple SMA modules according to the PWM control signals and simultaneously transmits the haptic feedback information from the SMA haptic feedback devices back to the control module, forming a closed-loop control. The control module adjusts the PWM control signals based on the feedback information and detects the on / off state and power supply time of the SMA modules, enabling real-time correction of control deviations and ensuring accurate on / off control and current regulation of the SMA modules, effectively reducing deformation errors of the SMA modules. The entire method has a clear logical flow and compact steps, achieving a combination of precise PWM control and MOSFET constant current drive, meeting the real-time requirements of VR interaction. It effectively solves the problems of single feedback mode, low control accuracy, and low power supply stability in existing technologies, improving system reliability and ease of use. Furthermore, the realization of collaborative control of multiple SMA modules enriches the haptic feedback modes and enhances the immersion and realism of VR interaction.

[0049] In all examples shown and described herein, any specific values ​​should be interpreted as merely exemplary and not as limitations; therefore, other examples of exemplary embodiments may have different values.

[0050] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A virtual reality multimodal haptic feedback control system based on SMA, characterized in that, Includes a VR host (100), a control system (200), and an SMA haptic feedback device (300). The control system (200) includes a control module (220), a power supply module (230), a drive module (240), and a crystal oscillator module (250). The signal terminals of the power supply module (230), the drive module (240), and the crystal oscillator module (250) are all connected to the signal terminal of the control module (220); The signal terminal of the VR host (100) is connected to the signal terminal of the control module (220); The SMA haptic feedback device (300) includes several SMA modules, and the signal terminals of the several SMA modules are connected to the signal terminals of the drive module (240).

2. The virtual reality multimodal haptic feedback control system based on SMA according to claim 1, characterized in that, The control system (200) also includes a communication module (260) and a reset module (270). The signal terminal of the reset module (270) is connected to the signal terminal of the control module (220), wherein the reset module (270) is used to provide a stable clock signal to the control module (220); The signal terminals of the communication module (260) are connected to the signal terminals of the VR host (100) and the control module (220) respectively, for bidirectional data transmission between the VR host (100) and the control system (200).

3. The virtual reality multimodal haptic feedback control system based on SMA according to claim 2, characterized in that, The communication module (260) includes a Bluetooth chip U4, and the reset module (270) includes a switch SW1, a capacitor CF1 and a resistor RF1; the resistor RF1 and the capacitor CF1 are both connected to the switch SW1 and the control module (220).

4. The virtual reality multimodal haptic feedback control system based on SMA according to claim 1, characterized in that, The control system (200) also includes an interaction module (280) and a download module (290). The signal terminals of the interaction module (280) and the download module (290) are both connected to the signal terminal of the control module (220). The interaction module (280) is used to debug or switch the working mode of the control system (200); the download module (290) is used to program the control system (200) or debug the system.

5. A virtual reality multimodal haptic feedback control system based on SMA according to claim 4, characterized in that, The interactive module (280) includes a first button circuit and a second button circuit. The first button circuit includes a resistor K1_R1, a capacitor K1_C1, a resistor K1_R2, and a switch K1. One end of the resistor K1_R1 is connected to one end of the capacitor K1_C1, one end of the resistor K1_R2, and the switch K1. The other end of the capacitor K1_C1 is connected to the switch K1. The other end of the resistor K1_R1 is grounded. The other end of the resistor K1_R2 is connected to the control module. The second button circuit includes a resistor K2_R1, a capacitor K2_C1, a resistor K2_R2, and a switch K2. One end of the resistor K2_R1 is connected to one end of the capacitor K2_C1, one end of the resistor K2_R2, and the switch K2. The other end of the capacitor K2_C1 is connected to the switch K2. The other end of the resistor K2_R1 is grounded. The other end of the resistor K2_R2 is connected to the control module.

6. A virtual reality multimodal haptic feedback control system based on SMA according to claim 4, characterized in that, The download module (290) includes a JTAG download port, which is used for programming and system debugging of the control module.

7. A virtual reality multimodal haptic feedback control system based on SMA according to claim 1, characterized in that, The power supply module (230) includes a first power supply circuit and a second power supply circuit; The first power supply circuit is used to power the SMA haptic feedback device (300), wherein the first power supply circuit includes chip U5, battery BT1, capacitor CB1, capacitor CB2, capacitor C3, capacitor C4, switch SW3, resistor RB1, resistor RB2, resistor RB3 and resistor RB4. The anode of battery BT1 is connected to one end of capacitor CB1, one end of capacitor CB2, and chip U5. The cathode of battery BT1 is connected to the first end of switch SW3. The second end of switch SW3 is connected to the other end of capacitor CB1, the other end of capacitor CB2, one end of resistor RB1, one end of resistor RB4, and chip U5. The other ends of resistor RB1 and resistor RB4 are connected to chip U5. One end of resistor RB2 and one end of resistor RB3 are both connected to chip U5. One end of capacitor C3 and one end of capacitor C4 are connected to chip U5 and connected to multiple SMA modules. The other ends of capacitor C3 and capacitor C4 are both connected to resistor RB3 and grounded. The second power supply circuit is used to supply power to the control module (220), the drive module (240) and the crystal oscillator module (250); wherein the second power supply circuit includes a USB conversion circuit, a switching circuit and a voltage regulator circuit; The USB conversion circuit includes chip U3, terminal USB2, capacitors CK_C1, CK_C2, CK_C3, CK_C4, and crystal oscillator CK_X1; One end of capacitor CK_C1 and capacitor CK_C2 are both connected to chip U3. One end of capacitor CK_C3 is connected to one end of crystal oscillator CK_X1 and chip U3. The other end of capacitor CK_C3 is connected to one end of capacitor CK_C4. The other end of capacitor CK_C4 is connected to crystal oscillator CK_X1 and chip U3. The other end of capacitor CK_C1 is connected to chip U3 and terminal USB2. The switching circuit includes a switch SW2, a TVS diode D1, and a fuse F1; One end of the switch SW2 is connected to the terminal USB2, and the other end of the switch SW2 is connected to the TVS diode D1 and the fuse F1. The voltage regulator circuit includes chip U2, capacitor C_WY1, capacitor C_WY2, capacitor C_WY3, capacitor C_WY4, resistor R_WY1, and diode LED_WY1; One end of capacitor C_WY1 and one end of capacitor C_WY2 are connected to chip U2 and fuse F1. One end of capacitor C_WY3 and one end of capacitor C_WY4 are connected to chip U2 and one end of resistor R_WY1. The other end of capacitor C_WY1 is connected to the other end of capacitor C_WY2, the other end of capacitor C_WY3, the other end of capacitor C_WY4, and the cathode of diode LED_WY1 and grounded. The other end of resistor R_WY1 is connected to the anode of diode LED_WY1.

8. A virtual reality multimodal haptic feedback control system based on SMA according to claim 1, characterized in that, The control module (220) includes a chip U1, several capacitors, inductors and several resistors; wherein several capacitors, inductors and several resistors are all connected to the chip U1; The driving module (240) includes multiple MOS transistors connected to chip U1. The gate of each MOS transistor is connected to the PB1 pin of chip U1, the drain of each MOS transistor is connected to chip U5, and the source of each MOS transistor is connected to each SMA module.

9. A virtual reality multimodal haptic feedback control system based on SMA according to claim 1, characterized in that, The crystal oscillator module (250) includes a first crystal oscillator circuit and a second crystal oscillator circuit; The first crystal oscillator circuit includes crystal OSC1, capacitor OSC_1, and capacitor OSC_2; One end of capacitor OSC_1 is connected to one end of crystal oscillator OSC1 and is connected to control module (220). The other end of capacitor OSC_2 is connected to one end of capacitor OSC_2 and grounded. The other end of capacitor OSC_2 is connected to the other end of crystal oscillator OSC1 and is connected to control module (220). The second crystal oscillator circuit includes crystal OSC2, crystal OSC3, capacitor OSC4, and capacitor OSC5; One end of capacitor OSC4 is connected to one end of crystal oscillator OSC2 and one end of crystal oscillator OSC3 and is connected to the control module (220). The other end of capacitor OSC4 is connected to one end of capacitor OSC5 and grounded. The other end of capacitor OSC5 is connected to the other end of crystal oscillator OSC2 and the other end of crystal oscillator OSC3 and is connected to the control module (220).

10. A virtual reality multimodal haptic feedback control method based on SMA, characterized in that, A virtual reality multimodal haptic feedback control system based on SMA according to any one of claims 1-9 includes the following process: After receiving the haptic commands from the VR host (100), the control module (220) parses the control parameters of multiple SMA modules and generates PWM control signals corresponding to the control parameters; The control module (220) sends a PWM control signal to the drive module (240). The drive module (240) drives multiple SMA modules according to the PWM control signal and sends haptic feedback information from the SMA haptic feedback device (300) to the control module (220). The control module (220) adjusts the PWM control signal according to the tactile feedback information to detect the status information of multiple SMA modules and completes virtual reality multimodal tactile feedback control. The status information includes on / off status and power supply time.

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