System for sensing direction based on phased array ultrasonic touch sense

Abstract

The invention relates to a system for sensing a direction based on phased array ultrasonic touch, and the system comprises an upper computer which is used for transmitting a touch mode control instruction capable of sensing the direction; the distance sensor is used for acquiring hand position information; the main controller is used for extracting tactile mode control parameters in the received instruction, calculating time delay and modulation information, processing hand position information, taking the hand position information as a basis of a system state, and correspondingly adjusting system state display and tactile mode output; the signal generator is used for converting the phase delay and modulation information into a driving signal of each transmitting channel; the ultrasonic transducer array is used for continuously emitting ultrasonic waves according to the driving signal and controlling sound field distribution of a target area in real time to generate direction perception tactile feedback; and the bracket and the bus are used for realizing structure supporting and signal transmission functions. According to the system, a hand position detection function, a control strategy of direction perception ultrasonic touch and a system scheme of direction perception touch experience are realized.

Description

Technical Field

[0001] The present invention relates to the field of ultrasonic tactile technology, and in particular to a system for sensing direction of ultrasonic tactile sensation based on a phased array. Background Art

[0002] Ultrasonic tactile sensation uses a phased array to control an airborne ultrasonic transmitter array to focus the acoustic amplitudes of all its array elements on one or more target points in space, and then modulates the acoustic energy intensity at the focal point so that the focus can be perceived by the mechanical receptors of the human hand as tactile stimulation, thereby achieving contactless tactile feedback. In the specific ultrasonic tactile experience, it needs to be used in combination with contactless external input detection technology. At present, most system solutions choose to complete human motion capture and hand fine movement recognition based on hand tracking algorithms and infrared cameras and other equipment, but this method is costly, computationally complex, and has strict restrictions on the interactive lighting environment, which is not convenient for application in some simple non-contact activation solutions. The current ultrasonic tactile feedback system lacks a functional, simple, scalable and convenient external input detection solution for relatively simple ultrasonic tactile application scenarios.

[0003] Ultrasonic tactile design usually uses the tactile focus as the basic unit, and renders special tactile feedback by controlling its movement pattern in the air. Current research mainly uses the rapid movement of a single focus point and the simultaneous movement of multiple focus points to render ultrasonic tactile feedback on the shape and texture surface of virtual three-dimensional objects. There is a lack of control methods for rendering ultrasonic tactile feedback using strategies for controlling the dynamic switching of different tactile focus groups. There is also a lack of specific solutions for ultrasonic tactile design that can perceive the rendering direction and an ultrasonic tactile feedback system that can experience the perception of the direction. Summary of the invention

[0004] The purpose of the present invention is to overcome the problems existing in the prior art and provide a system for tactile perception direction based on phased array ultrasonic waves.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is: a system based on phased array ultrasonic tactile perception direction, comprising: The host computer is used to send direction-aware tactile mode control instructions; Distance sensor, used to obtain hand position information as a basis for judging the system status; A main controller, which is used to extract the tactile pattern control parameters in the received instructions and calculate the corresponding time delay and modulation information, process the hand position information as the basis of the system state, and make corresponding adjustments to the system state display and tactile pattern output; A signal generator, used for converting the received phase delay and modulation information into a driving signal for each transmitting channel; Ultrasonic transducer array, used to continuously emit ultrasonic waves according to the driving signal, and to control the sound field distribution in the target area in real time to generate direction-aware tactile feedback; The bracket and bus are used to ensure that the distance sensor and the ultrasonic transducer array are in suitable relative positions, and the bus is used to realize the transmission of control signals between various components of the system.

[0006] Furthermore, the distance sensor is connected to the main controller to detect the position information of the user's hand in real time and send it to the main controller for processing, which is used as a basis for judging the state of the tactile interaction system.

[0007] Furthermore, the main controller is respectively connected to the distance sensor, the signal generator and the host computer, receives the direction-perceivable tactile mode control instruction sent by the host computer, extracts the tactile mode control parameters in the instruction, calculates the corresponding phase delay and modulation information, and then sends it to the signal generator; the main controller also processes the information of the distance sensor, adjusts the system status and the output of the tactile mode according to the system settings in real time, and provides auxiliary functions of system status display and recovery.

[0008] Furthermore, the signal generator is connected to the main controller, calculates and generates a corresponding driving signal for each transmitting channel according to the phase delay and modulation signal information received from the main controller, and amplifies the signal to excite the ultrasonic transducer array.

[0009] Furthermore, the ultrasonic transducer array is connected to a signal generator and is continuously stimulated by a driving signal of the signal generator to emit ultrasonic waves, thereby achieving a set sound field control in a target area. When the array applies force feedback to the hand, the tactile point will continue to stay at different positions along a specified direction for a period of time, creating ultrasonic tactile feedback that enables the user to sense the direction.

[0010] Furthermore, the bracket sets the distance sensor and the ultrasonic transducer array in a central relative position relationship to ensure the correct input of hand position information. The bus connects the distance sensor to the main controller, the main controller to the host computer, and the main controller to the signal generator to ensure normal communication between the various components of the system.

[0011] Furthermore, the implementation method of detecting the hand position to obtain the hand position information is as follows: Firstly, two distance intervals with different heights and parallel to the array plane are set above the ultrasonic transducer array as the detection area for tactile interaction; then, the height position information of the target user's hand relative to the ultrasonic transducer array plane is detected in real time by the distance sensor, and then the data is filtered by the recursive averaging algorithm in the main controller to obtain more stable position data under the condition of allowable delay; Then, a state machine design pattern is adopted to construct four identifiable hand states according to the real-time position relationship between the hand and the detection area, namely, idle state, single-click state, double-click state, and long-press state. The four states have their own identifiers for subsequent use by the system. In the main controller, first, whether the real-time position of the hand and the detection area intersect is judged to distinguish whether to switch from the idle state to one of the other three states. When an intersection is detected, a software timer is used to obtain the length of time the hand stays in the detection area to distinguish switching to the long-press state or the remaining two states. Then, a timer with a fixed time interval is set to judge the number of intersections detected within this interval to distinguish switching to the single-click state or the double-click state. At the same time, after switching to the single-click state or the double-click state, it will immediately switch to the idle state, and the long-press state will be maintained until the user's hand leaves the detection area and then switch to the idle state. Finally, the filtered hand position data is input into the state machine to detect the user's three one-dimensional gesture recognition inputs, and then different gestures are assigned as trigger conditions for different functions of the system.

[0012] Furthermore, the control strategy for ultrasonic tactile perception of direction is implemented as follows: First, the control strategy of the ultrasonic phased array formulated for the direction pointer presented in the palm area is written into the host computer, and then the host computer converts its calculation into various control parameters of the head and end of the direction pointer, including focusing mode, modulation frequency, focusing time period, and spatial coordinates of the focus; Then, the host computer edits the control parameters into instructions and sends them to the main controller via the serial port. The main controller waits for the instructions to be received and stores them in the system buffer. Then, the received instructions are identified and their validity is verified to prevent illegal instructions from being input. The parameters in the verified instructions are then extracted and converted into system control parameters for the direction-sensing tactile feedback ultrasonic phased array. The main controller is embedded with a phase algorithm for multi-point and single-point focusing, an algorithm for converting amplitude modulation frequency into clock count values, and a software timer for controlling the focusing duration period. The phase delay and modulation control information of the direction pointer head and end focus groups are obtained by inputting corresponding parameters into the corresponding algorithms, and then the system timer is used to accurately control the focusing time period of the head and end and the switching time point of the end focus group. According to the information and functions obtained, the embedded system of the main controller is used to first transmit information to control the head end to continue single-point focusing within a specified time limit, and then when the system time reaches the head and end switching time point, information is transmitted again to control the end to continue multi-point focusing within a specified time limit and position. By completing the transmission conversion of control information of different tactile focus groups at the head and end within the constrained time limit, the signal generator generates a corresponding signal based on the received data to excite the ultrasonic array to emit ultrasonic waves, so that an ultrasonic tactile feedback capable of sensing direction can be completed in the target area.

[0013] Furthermore, the method for realizing the direction perception tactile experience is as follows: Three recognizable one-dimensional gestures are used: single click, double click, and long press, as trigger gestures for system on, system off, and system in tactile feedback state, respectively, to ensure that the target user's hand stays correctly in the detection area when the system is on; then the ultrasonic tactile control strategy for sensing direction is used to apply tactile perception of the direction set by the user; the entire tactile experience control process is scheduled by the embedded system of the main controller, and the system indicator lights and buttons are used to assist in displaying and switching the system status.

[0014] Furthermore, the control logic of the system is as follows: First, turn on the system power supply, and the system initializes the software and hardware of each part after power-on, including opening the communication port of the host computer software, activating the real-time operating system and system status indicator light running on the main controller, turning on and detecting the sampling function of the distance sensor, and enabling the signal generator and ultrasonic transducer array; Then, the distance sensor is used to detect the target user's hand position in real time to determine whether the target user has performed a single-click gesture. If so, the system initializes the parameters and the tactile experience officially begins. If not, wait until the user performs a single-click gesture. On this basis, it continues to determine whether the target user maintains a long press gesture. If the main controller controls the system status indicator to switch to the interactive state, and the upper computer software sends the first instruction of the tactile instruction sequence to the main controller, the main controller uses the phase optimization algorithm to calculate the phase delay of the tactile point to be generated, and sends it together with the modulation information to the signal generator continuously according to the set control strategy. If not, wait for the user to use a long press gesture; The signal generator processes the continuously received phase delay and modulation information to generate a driving signal for each ultrasonic transducer channel to continuously excite the ultrasonic transducer array, thereby controlling the tactile focus group to act as a direction pointer in the tactile interaction area to induce the user to have a sense of direction. Each time a tactile interaction is completed, it will detect whether the user's hand is out of the tactile interaction area. If not, the direction of the tactile perception mode will be changed and the corresponding tactile command will be generated, and the system will continue to be in the interactive state. If it is, the system will enter the sleep state and the system status indicator will switch to the initial state; Then determine whether the target user has performed a double-click gesture. If not, wait for the key function of the main controller to restore the system for the next round of tactile interaction experience. If yes, declare the end of this round of direction perception tactile experience.

[0015] Compared with the prior art, the present invention has the following beneficial effects: 1) The external hand input detection scheme proposed in the present invention simplifies the computational complexity required for obtaining hand information using computer vision in traditional ultrasonic tactile feedback systems. At the same time, the module's small size, low cost, simple operation, and rich functions make it easier to flexibly adjust its usage in different ultrasonic tactile experience scenarios, making it more practical and broadening the design space of ultrasonic tactile experience.

[0016] 2) The control scheme for rendering directional-aware ultrasonic tactile sensations proposed in the present invention uses a design method different from previous methods for rendering ultrasonic tactile sensations to precisely control the movement mode from a single focus to multiple focuses to render directional-aware tactile sensations. This provides new ideas for ultrasonic tactile sensation design and fills the gap in ultrasonic tactile sensation design in rendering directional perception. Ultrasonic tactile sensation feedback with directional perception can be used to integrate directional information into various digital interactive experiences, or to achieve more complex tactile perception of shapes and patterns based on this, providing new functions for the development of tactile experiences.

[0017] 3) The present invention proposes a system solution for directional ultrasonic tactile experience integrating gesture recognition. Its simple structure and complete functions can be more easily integrated into various contactless experiences. It is very suitable for providing implicit tactile clues for contactless activation solutions for various public service application scenarios such as opening and closing doors, faucets, flushing toilets, and payments. This can reduce the spread of diseases during use and is a more hygienic solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of the system structure of an embodiment of the present invention; Figure 2 is a schematic diagram of a control strategy for ultrasonic tactile perception of direction in an embodiment of the present invention; Figure 3 It is a system control logic flow chart of an embodiment of the present invention.

[0019] In the figure: 1-host computer; 2-bracket and bus; 3-main controller; 4-distance sensor; 5-tactile feedback area; 6-user interaction hand; 7-tactile point; 8-ultrasonic transducer array; 9-signal generator. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0021] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0022] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0023] like Figure 1 As shown, this embodiment provides a system for tactile sensing direction based on phased array ultrasonic waves, including: Host computer 1, used for sending direction-aware tactile mode control instructions; Distance sensor 4, used to obtain hand position information as a basis for judging the system status; The main controller 3 is used to extract the tactile mode control parameters in the received instructions and calculate the corresponding time delay and modulation information, process the hand position information as the basis of the system state, and make corresponding adjustments to the system state display and the tactile mode output; A signal generator 9, used to convert the received phase delay and modulation information into a driving signal for each transmission channel; The ultrasonic transducer array 8 is used to continuously emit ultrasonic waves according to the driving signal, and to control the sound field distribution of the target area in real time to generate direction-aware tactile feedback; The bracket and bus 2, wherein the bracket is used to ensure that the distance sensor and the ultrasonic transducer array are in a suitable relative position, and the bus is used to realize the transmission of control signals between various components of the system.

[0024] The distance sensor 4 is connected to the main controller 3 to detect the position information of the user's hand in real time and send it to the main controller for processing, which is used as a basis for judging the state of the tactile interaction system.

[0025] The main controller 3 is connected to the distance sensor 4, the signal generator 9 and the host computer 1 respectively, receives the direction-perceptible tactile mode control instruction sent by the host computer, extracts the tactile mode control parameters in the instruction, calculates the corresponding phase delay and modulation information, and then sends it to the signal generator; the main controller also processes the information of the distance sensor, adjusts the system status and the output of the tactile mode according to the system settings in real time, and provides auxiliary functions of system status display and recovery.

[0026] The signal generator 9 is connected to the main controller 3, and calculates and generates a corresponding driving signal for each transmitting channel according to the phase delay and modulation signal information received from the main controller, and amplifies the signal to excite the ultrasonic transducer array.

[0027] The ultrasonic transducer array 8 is connected to the signal generator 9, and is continuously stimulated by the driving signal of the signal generator to emit ultrasonic waves, thereby achieving the set sound field control in the target area. When the array applies force feedback to the hand, the tactile point will continue to stay at different positions along the specified direction for a period of time, creating ultrasonic tactile feedback that enables the user to sense the direction.

[0028] In the bracket and bus 2, the bracket sets the distance sensor and the ultrasonic transducer array in a central relative position relationship to ensure the correct input of the hand position information. The bus connects the distance sensor to the main controller, the main controller to the host computer, and the main controller to the signal generator to ensure normal communication between the various components of the system.

[0029] Figure 1 In the figure, 5 is an adjustable tactile feedback area with a certain range set by the system; 6 is the user's interactive hand, and 7 is a tactile point generated by the modulated ultrasonic focusing and can be controlled by a set control strategy to enable the user to have a sense of direction.

[0030] The upper computer software 1 stores tactile instructions pointing in different directions. The instructions include the height of the target domain, the spatial position of the tactile point movement and the time interval parameters. In terms of use, tactile instructions in the corresponding direction can be emitted according to the specific situation, and tactile instructions in different directions can be sent continuously in a certain order to adapt to more contactless application scenarios.

[0031] The tactile feedback area 5 is a detection area set by the system for tactile interaction with the user's hand. The height and size of the area can be adjusted according to the needs of different non-contact experiences, and can be flexibly combined with different virtual experience systems.

[0032] The tactile point 7 is the phased array ultrasonic focusing point after amplitude modulation, and is also the basic unit of ultrasonic tactile design for realizing direction perception, such as Figure 2 As shown, the present invention provides a control strategy for ultrasonic tactile perception of direction, taking the palm area of ​​the human hand as the target area for tactile feedback, setting two positions as two endpoints representing the direction pointer, using single-point focused tactile feedback at the initial endpoint, and using a multi-point phase algorithm at the end endpoint to generate multi-point focused tactile feedback, while precisely controlling the duration of the tactile feedback at the two end points and the switching time point of the focus group, and realizing ultrasonic tactile feedback for user perception of direction by controlling the movement pattern of the tactile focus group.

[0033] The present invention solves the problem that the current ultrasonic tactile feedback system lacks an external hand input detection solution that is excellent in function, simple, highly scalable and convenient for use as a relatively simple ultrasonic tactile application scenario. It proposes three one-dimensional gesture recognitions in a specified target area based on a distance sensor and a microcontroller combined with a state machine design pattern, which can be integrated into the ultrasonic tactile interaction system as a trigger condition for external input detection; it solves the lack of rendering direction perception in ultrasonic tactile design, and proposes a new control strategy for rendering direction perception ultrasonic tactile by accurately controlling a motion mode that dynamically switches from a single focus to multiple focuses, and provides a complete set of control solutions for rendering direction perception ultrasonic tactile. On this basis, combined with the above solutions, a system for experiencing direction perception ultrasonic tactile feedback is proposed.

[0034] 1. Detecting the hand position to obtain the hand position information Firstly, two distance intervals with different heights and parallel to the array plane are set above the ultrasonic transducer array as the detection area for tactile interaction. Then, the height position information of the target user's hand relative to the ultrasonic transducer array plane is detected in real time by the distance sensor. Then, the data is filtered by the recursive averaging algorithm in the main controller to obtain more stable position data under the condition of tolerable delay.

[0035] Then, a state machine design pattern is adopted to construct four identifiable hand states according to the real-time position relationship between the hand and the detection area, namely, idle state, single-click state, double-click state, and long-press state. The four states have their own identifiers for subsequent use by the system. In the main controller, first, whether the real-time position of the hand and the detection area intersect is judged to distinguish whether to switch from the idle state to one of the other three states. When an intersection is detected, a software timer is used to obtain the length of time the hand stays in the detection area to distinguish the switch to the long-press state or the remaining two states. Then, a timer with a fixed time interval is set to judge the number of intersections detected within this interval to distinguish the switch to the single-click state or the double-click state. At the same time, after switching to the single-click state or the double-click state, it will immediately switch to the idle state, and the long-press state will be maintained until the user's hand leaves the detection area and then switch to the idle state.

[0036] Finally, the filtered hand position data is input into the state machine to detect the user's three one-dimensional gesture recognition inputs, and then different gestures are assigned as trigger conditions for different functions of the system.

[0037] 2. Implementation of control strategy for rendering direction-aware ultrasonic tactile First, the control strategy of the ultrasonic phased array formulated for the direction pointer presented in the palm area is written into the host computer, and then the host computer converts its calculation into various control parameters of the head and end of the direction pointer, including focusing mode, modulation frequency, focusing time period, and spatial coordinates of the focus.

[0038] Then, the host computer edits the control parameters into instructions and sends them to the main controller via the serial port. The main controller waits for the instructions to be received and stores them in the system cache. It then identifies the received instructions and verifies their validity to prevent illegal instructions from being input. It then extracts the parameters in the verified instructions and converts them into system control parameters for the direction-aware tactile feedback ultrasonic phased array.

[0039] The main controller is embedded with a phase algorithm for multi-point and single-point focusing, an algorithm for converting amplitude modulation frequency into clock count values, and a software timer for controlling the focusing duration period. The phase delay and modulation control information of the direction pointer head and end focus groups are obtained by inputting corresponding parameters into the corresponding algorithms, and then the system timer is used to accurately control the focusing time period of the head and end and the switching time point of the end focus group. According to the information and functions obtained, the embedded system of the main controller is used to first transmit information to control the head end to continue single-point focusing within a specified time limit, and then when the system time reaches the head and end switching time point, information is transmitted again to control the end to continue multi-point focusing within a specified time limit and position. By completing the transmission conversion of control information of different tactile focus groups at the head and end within the constrained time limit, the signal generator generates a corresponding signal based on the received data to excite the ultrasonic array to emit ultrasonic waves, so that an ultrasonic tactile feedback capable of sensing direction can be completed in the target area.

[0040] 3. Realization of directional perception tactile experience The three recognizable one-dimensional gestures implemented in (I): single click, double click, and long press are used as trigger gestures for system on, system off, and system in tactile feedback state, respectively, to ensure that the target user's hand stays correctly in the detection area when the system is on. Then, the control strategy for ultrasonic tactile perception of direction implemented in (II) is used to apply tactile perception of the direction set by the user. The entire tactile experience control process is scheduled by the embedded system of the main controller, and the system indicator light and buttons are used to assist in displaying and switching the system status.

[0041] like Figure 3 As shown, the control logic of the phased array ultrasonic tactile direction perception system provided in this embodiment is as follows: First, turn on the system power supply, and the system initializes the software and hardware of each part after power-on, including opening the communication port of the host computer software, activating the real-time operating system and system status indicator light running on the main controller, turning on and detecting the sampling function of the distance sensor, and enabling the signal generator and ultrasonic transducer array.

[0042] Then, the distance sensor is used to detect the target user's hand position in real time to determine whether the target user has performed a single-click gesture. If so, the system initializes the parameters and the tactile experience officially begins. If not, wait until the user uses a single-click gesture.

[0043] On this basis, continue to judge whether the target user maintains a long press gesture. If so, the main controller controls the system status indicator to switch to the interactive state, and the upper computer software sends the first instruction of the tactile instruction sequence to the main controller. The main controller uses the phase optimization algorithm to calculate the phase delay of the tactile point to be generated, and sends it together with the modulation information to the signal generator according to the set control strategy. If not, wait for the user to use a long press gesture.

[0044] The signal generator processes the continuously received phase delay and modulation information to generate a driving signal for each ultrasonic transducer channel to continuously excite the ultrasonic transducer array, thereby controlling the movement mode of the tactile focus group as a directional pointer in the tactile interaction area to induce the user to have a sense of direction.

[0045] Each time a tactile interaction is completed, it will detect whether the user's hand has left the tactile interaction area. If not, the direction of the tactile perception mode will be changed and the corresponding tactile instructions will be generated, and the system will continue to be in an interactive state. If so, the system will enter a sleep state and the system status indicator light will switch to the initial state.

[0046] Then determine whether the target user has performed a double-click gesture. If not, wait for the key function of the main controller to restore the system for the next round of tactile interaction experience. If yes, declare the end of this round of direction perception tactile experience.

[0047] The above is only a preferred embodiment of the present invention, and does not limit the present invention in other forms. Any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the technical solution of the present invention still belongs to the protection scope of the technical solution of the present invention.

Claims

1. A system based on phased array ultrasonic tactile perception direction, characterized in that: include: The host computer is used to send direction-aware tactile mode control instructions; Distance sensor, used to obtain hand position information as a basis for judging the system status; A main controller, which is used to extract the tactile pattern control parameters in the received instructions and calculate the corresponding time delay and modulation information, process the hand position information as the basis of the system state, and make corresponding adjustments to the system state display and tactile pattern output; A signal generator, used for converting the received phase delay and modulation information into a driving signal for each transmitting channel; Ultrasonic transducer array, used to continuously emit ultrasonic waves according to the driving signal, and to control the sound field distribution in the target area in real time to generate direction-aware tactile feedback; The bracket and bus are used to ensure that the distance sensor and the ultrasonic transducer array are in suitable relative positions, and the bus is used to realize the transmission of control signals between various components of the system.

2. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The distance sensor is connected to the main controller, detects the position information of the user's hand in real time and sends it to the main controller for processing, which is used as a basis for judging the state of the tactile interaction system.

3. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The main controller is connected to the distance sensor, the signal generator and the host computer respectively, receives the direction-perceptible tactile mode control instruction sent by the host computer, extracts the tactile mode control parameters in the instruction, calculates the corresponding phase delay and modulation information, and then sends it to the signal generator; the main controller also processes the information of the distance sensor, adjusts the system status and the output of the tactile mode in real time according to the system settings, and provides auxiliary functions of system status display and recovery.

4. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The signal generator is connected to the main controller, and calculates and generates a corresponding driving signal for each transmitting channel according to the phase delay and modulation signal information received from the main controller, and amplifies the signal to excite the ultrasonic transducer array.

5. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The ultrasonic transducer array is connected to a signal generator and is continuously stimulated by the driving signal of the signal generator to emit ultrasonic waves, thereby achieving the set sound field control in the target area. When the array applies force feedback to the hand, the tactile point will continue to stay at different positions along the specified direction for a period of time, creating ultrasonic tactile feedback that enables the user to sense the direction.

6. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The bracket sets the distance sensor and the ultrasonic transducer array in a central relative position relationship to ensure the correct input of hand position information. The bus connects the distance sensor to the main controller, the main controller to the host computer, and the main controller to the signal generator to ensure normal communication between the various components of the system.

7. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The implementation method of detecting the hand position to obtain the hand position information is: Firstly, two distance intervals with different heights and parallel to the array plane are set above the ultrasonic transducer array as the detection area for tactile interaction; then, the height position information of the target user's hand relative to the ultrasonic transducer array plane is detected in real time by the distance sensor, and then the data is filtered by the recursive averaging algorithm in the main controller to obtain more stable position data under the condition of allowable delay; Then, a state machine design pattern is adopted to construct four identifiable hand states according to the real-time position relationship between the hand and the detection area, namely, idle state, single-click state, double-click state, and long-press state. The four states have their own identifiers for subsequent use by the system. In the main controller, first, whether the real-time position of the hand and the detection area intersect is judged to distinguish whether to switch from the idle state to one of the other three states. When an intersection is detected, a software timer is used to obtain the length of time the hand stays in the detection area to distinguish switching to the long-press state or the remaining two states. Then, a timer with a fixed time interval is set to judge the number of intersections detected within this interval to distinguish switching to the single-click state or the double-click state. At the same time, after switching to the single-click state or the double-click state, it will immediately switch to the idle state, and the long-press state will be maintained until the user's hand leaves the detection area and then switch to the idle state. Finally, the filtered hand position data is input into the state machine to detect the user's three one-dimensional gesture recognition inputs, and then different gestures are assigned as trigger conditions for different functions of the system.

8. The system for tactile perception direction based on phased array ultrasonic waves according to claim 1, characterized in that: The control strategy for ultrasonic tactile sensing of direction is implemented as follows: First, the control strategy of the ultrasonic phased array formulated for the direction pointer presented in the palm area is written into the host computer, and then the host computer converts its calculation into various control parameters of the head and end of the direction pointer, including focusing mode, modulation frequency, focusing time period, and spatial coordinates of the focus; Then, the host computer edits the control parameters into instructions and sends them to the main controller via the serial port. The main controller waits for the instructions to be received and stores them in the system buffer. Then, the received instructions are identified and their validity is verified to prevent illegal instructions from being input. The parameters in the verified instructions are then extracted and converted into system control parameters for the direction-sensing tactile feedback ultrasonic phased array. The main controller is embedded with a phase algorithm for multi-point and single-point focusing, an algorithm for converting amplitude modulation frequency into clock count values, and a software timer for controlling the focusing duration period. The phase delay and modulation control information of the direction pointer head and end focus groups are obtained by inputting corresponding parameters into the corresponding algorithms, and then the system timer is used to accurately control the focusing time period of the head and end and the switching time point of the end focus group. According to the information and functions obtained, the embedded system of the main controller is used to first transmit information to control the head end to continue single-point focusing within a specified time limit, and then when the system time reaches the head and end switching time point, information is transmitted again to control the end to continue multi-point focusing within a specified time limit and position. By completing the transmission conversion of control information of different tactile focus groups at the head and end within the constrained time limit, the signal generator generates a corresponding signal based on the received data to excite the ultrasonic array to emit ultrasonic waves, so that an ultrasonic tactile feedback capable of sensing direction can be completed in the target area.

9. The system for tactile perception direction based on phased array ultrasonic waves according to claim 1, characterized in that: The method to achieve the direction perception tactile experience is: Three recognizable one-dimensional gestures are used: single click, double click, and long press, as trigger gestures for system on, system off, and system in tactile feedback state, respectively, to ensure that the target user's hand stays correctly in the detection area when the system is on; then the ultrasonic tactile control strategy for sensing direction is used to apply tactile perception of the direction set by the user; the entire tactile experience control process is scheduled by the embedded system of the main controller, and the system indicator lights and buttons are used to assist in displaying and switching the system status.

10. The system for tactile perception direction based on phased array ultrasonic wave according to claim 1, characterized in that: The control logic of the system is as follows: First, turn on the system power supply, and the system initializes the software and hardware of each part after power-on, including opening the communication port of the host computer software, activating the real-time operating system and system status indicator light running on the main controller, turning on and detecting the sampling function of the distance sensor, and enabling the signal generator and ultrasonic transducer array; Then, the distance sensor is used to detect the target user's hand position in real time to determine whether the target user has performed a single-click gesture. If so, the system initializes the parameters and the tactile experience officially begins. If not, wait until the user performs a single-click gesture. On this basis, it continues to determine whether the target user maintains a long press gesture. If the main controller controls the system status indicator to switch to the interactive state, and the upper computer software sends the first instruction of the tactile instruction sequence to the main controller, the main controller uses the phase optimization algorithm to calculate the phase delay of the tactile point to be generated, and sends it together with the modulation information to the signal generator continuously according to the set control strategy. If not, wait for the user to use a long press gesture; The signal generator processes the continuously received phase delay and modulation information to generate a driving signal for each ultrasonic transducer channel to continuously excite the ultrasonic transducer array, thereby controlling the tactile focus group to act as a direction pointer in the tactile interaction area to induce the user to have a sense of direction. Each time a tactile interaction is completed, it will detect whether the user's hand is out of the tactile interaction area. If not, the direction of the tactile perception mode will be changed and the corresponding tactile command will be generated, and the system will continue to be in the interactive state. If it is, the system will enter the sleep state and the system status indicator will switch to the initial state; Then determine whether the target user has performed a double-click gesture. If not, wait for the key function of the main controller to restore the system for the next round of tactile interaction experience. If yes, declare the end of this round of direction perception tactile experience.

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