A system for tactile directional perception based on phased array ultrasound

Abstract

The application relates to a system for perceiving the direction of phased array ultrasonic tactile sensation, comprising: an upper computer for sending a tactile mode control instruction capable of perceiving the direction; a distance sensor for acquiring hand position information; a main controller for extracting tactile mode control parameters in the received instruction and calculating time delay and modulation information, processing the hand position information as the basis of the system state, and making corresponding adjustments to the system state display and tactile mode output; a signal generator for converting the phase delay and modulation information into the driving signal of each transmission channel; an ultrasonic transducer array for continuously transmitting ultrasonic waves according to the driving signal, and controlling the sound field distribution of the target area in real time to generate directional perception tactile feedback; a support and a bus for realizing the functions of structural support and signal transmission. The system realizes the functions of hand position detection, the control strategy of directional perception ultrasonic tactile sensation, and the system scheme of directional perception tactile experience.

Description

Technical Field

[0001] This invention relates to the field of ultrasonic tactile technology, and more specifically to a system for sensing the direction of ultrasonic tactile sensation based on a phased array. Background Technology

[0002] Ultrasonic haptic feedback utilizes a phased array to control an airborne ultrasonic transmitter array, focusing the acoustic amplitude of all its elements onto one or more target points in space. By modulating the acoustic energy intensity at the focal point, the focus can be perceived as a tactile stimulus by the mechanoreceptors of the hand, thus achieving contactless tactile feedback. In practical ultrasonic haptic experiences, it needs to be combined with contactless external input detection technology. Currently, most systems rely on hand tracking algorithms and infrared cameras to capture human motion and recognize fine hand movements. However, this method is costly, computationally complex, and has strict limitations on the lighting conditions during interaction, making it unsuitable for simple non-contact activation schemes. Currently, ultrasonic haptic feedback systems lack a high-performance, simple, highly scalable, and convenient external input detection solution for relatively simple ultrasonic haptic application scenarios.

[0003] Ultrasonic haptic design typically uses haptic focal points as the basic unit, rendering specific haptic feedback by controlling their movement patterns in the air. Current research mainly uses rapid movement of a single focal point and simultaneous movement of multiple focal points to render ultrasonic haptic feedback for the shape and textured surface of virtual 3D objects. It lacks control methods for rendering ultrasonic haptic feedback using strategies that dynamically switch between different haptic focal point groups, and also lacks specific solutions for ultrasonic haptic design that is directionally perceptible and for ultrasonic haptic feedback systems capable of providing directional feedback. Summary of the Invention

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

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a system for sensing direction based on phased array ultrasonic tactile perception, comprising:

[0006] The host computer is used to send haptic control commands that can sense direction.

[0007] A distance sensor is used to acquire hand position information as a basis for judging the system status;

[0008] The main controller is used to extract the haptic mode control parameters from the received instructions and calculate the corresponding time delay and modulation information, process the hand position information as the basis for the system status, and make corresponding adjustments to the system status display and haptic mode output.

[0009] A signal generator is used to convert the received phase delay and modulation information into drive signals for each transmission channel;

[0010] An ultrasonic transducer array is used to continuously emit ultrasonic waves according to a drive signal, and control the sound field distribution of the target area in real time to generate directional tactile feedback.

[0011] The system includes a support bracket and a bus, where the support bracket ensures that the distance sensor and the ultrasonic transducer array are in a suitable relative position, and the bus is used to transmit control signals between the various components of the system.

[0012] 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, thereby serving as the basis for judging the state of the haptic interaction system.

[0013] Furthermore, the main controller is connected to the distance sensor, the signal generator, and the host computer, respectively. It receives haptic mode control commands with perceptible direction sent by the host computer, extracts the haptic mode control parameters in the commands, calculates the corresponding phase delay and modulation information, and then sends it to the signal generator. The main controller also processes the information from the distance sensor, adjusts the system status and haptic mode output in real time according to the system settings, and provides auxiliary functions for system status display and recovery.

[0014] Furthermore, the signal generator is connected to the main controller, and calculates and generates the corresponding drive signal for each transmission channel based on the phase delay and modulation signal information sent by the main controller, and amplifies the signal to excite the ultrasonic transducer array.

[0015] Furthermore, the ultrasonic transducer array is connected to a signal generator and is continuously excited by the drive 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 stay at different positions along the specified direction for a period of time, creating ultrasonic tactile feedback that allows the user to perceive direction.

[0016] Furthermore, the bracket positions the distance sensor and the ultrasonic transducer array in a centrally opposite position 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.

[0017] Furthermore, the method for detecting hand position to obtain hand position information is as follows:

[0018] First, a detection area for tactile interaction is set above the ultrasonic transducer array, consisting of two distance intervals at different heights and parallel to the array plane. Then, the height position information of the target user's hand relative to the ultrasonic transducer array plane is detected in real time by a distance sensor. Finally, the data is filtered by a recursive averaging algorithm in the main controller to obtain more stable position data that meets the requirements of acceptable delay.

[0019] Then, using a state machine design pattern, four identifiable hand states are constructed based on the real-time positional relationship between the hand and the detection area: idle state, single-click state, double-click state, and long-press state. Each of the four states has its own identifier for subsequent use by the system. In the main controller, the system first determines whether to switch from the idle state to one of the other three states by judging whether the real-time position of the hand intersects with the detection area. When an intersection is detected, a software timer is used to obtain the length of time the hand stays in the detection area, thereby distinguishing whether to switch to the long-press state or one of the other two states. Then, by setting a timer with a fixed time interval, the system determines whether to switch to the single-click state or double-click state by judging the number of intersection detections within this interval. After switching to the single-click state or double-click state, the system immediately switches back to the idle state, while the long-press state is maintained until the user's hand leaves the detection area before switching back to the idle state.

[0020] Finally, the filtered hand position data is input into the state machine, where three types of one-dimensional gesture recognition inputs from the user are detected. Different gestures are then used as trigger conditions for different functions of the system.

[0021] Furthermore, the implementation method of the control strategy for ultrasonic haptics used to sense direction is as follows:

[0022] First, the control strategy of the ultrasonic phased array for the direction pointer presented in the palm area is written into the host computer. Then, the host computer calculates and converts it into various control parameters of the first and last ends of the direction pointer, including focusing mode, modulation frequency, focusing time period, and spatial coordinates of the focus.

[0023] Then, the host computer edits the control parameters into instructions and sends them to the main controller via serial port. After the main controller waits for the instructions to be received, it stores them in the system buffer. Then, it identifies and verifies the validity of the received instructions to prevent illegal instruction input. Then, it extracts the parameters from the verified instructions and converts them into system control parameters for the directional sensing tactile feedback ultrasonic phased array.

[0024] The main controller embeds phase algorithms for multi-point and single-point focusing, algorithms for converting amplitude modulation frequency into clock count values, and software timers for controlling the focusing duration period. By inputting corresponding parameters into the corresponding algorithms, the phase delay and modulation control information of the first and last focus groups of the direction pointer are obtained. Then, the system timer is used to precisely control the focusing time period of the first and last ends and the switching time of the end focus group. Based on the obtained information and functions, the embedded system of the main controller first transmits information to control the first end to continuously perform single-point focusing for a specified time limit. Then, when the system time reaches the first and last end switching time point, information is transmitted again to control the last end to continuously perform multi-point focusing for a specified time limit and position. By completing the transmission conversion of control information for different tactile focus groups of the first and last ends within the constrained time limit, the signal generator generates corresponding signals based on the received data to excite the ultrasonic array to emit ultrasonic waves, thus completing a directional ultrasonic tactile feedback within the target area.

[0025] Furthermore, the method for implementing directional tactile experience is as follows:

[0026] Using three recognizable one-dimensional gestures—single, double, and long press—as trigger gestures for system on, system off, and system in haptic feedback state, respectively, the system ensures that the target user's hand is correctly positioned within the detection area when the system is on. Then, an ultrasonic haptic control strategy for sensing direction is used to apply the user's set directional haptic feedback. The entire haptic experience control process is scheduled by the embedded system of the main controller, and system indicator lights and buttons are used to assist in displaying and switching system states.

[0027] Furthermore, the control logic of this system is as follows:

[0028] First, the system power is turned on. The system initializes the hardware and software 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 lights 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.

[0029] Then, the distance sensor detects the target user's hand position in real time to determine whether the target user has made a click gesture. If so, the system initializes the parameters and the haptic experience officially begins; otherwise, it waits until the user makes a click gesture.

[0030] Based on this, it continues to determine 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 at the same time, the host computer software sends the first instruction of the haptic instruction sequence to the main controller. The main controller uses a phase optimization algorithm to calculate the phase delay of the haptic point to be generated, and sends it along with the modulation information to the signal generator in accordance with the set control strategy. If not, it waits for the user to use a long press gesture.

[0031] The signal generator processes the continuously received phase delay and modulation information to generate a drive signal for each ultrasonic transducer channel, which continuously excites the ultrasonic transducer array, thereby controlling the motion mode of the tactile focus group as a direction pointer in the tactile interaction area to induce the user to generate direction perception.

[0032] Each time a tactile interaction is completed, the system will detect whether the user's hand has left the tactile interaction area. If not, the system will change the direction of the tactile perception mode and generate the corresponding tactile command, 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.

[0033] Then it determines whether the target user has performed a double-tap gesture. If not, it waits for the main controller's button function to restore the system for the next round of tactile interaction. If so, it declares the end of this round of directional tactile experience.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] 1) The external hand input detection scheme proposed in this invention simplifies the computational complexity required to obtain hand information using computer vision in traditional ultrasonic haptic feedback systems. At the same time, the module's small size, low cost, simple operation, and rich functionality make it easier to flexibly adjust its usage in different ultrasonic haptic experience scenarios, making it more practical and expanding the design space of ultrasonic haptic experience.

[0036] 2) The control scheme for rendering direction-aware ultrasonic haptics proposed in this invention uses a design method different from previous ultrasonic haptics rendering methods to precisely control the motion mode from single focus to multi focus to render direction-aware haptics. This provides a new idea for ultrasonic haptics design and fills the gap in ultrasonic haptics design in rendering direction awareness. Ultrasonic haptic feedback with direction awareness can be used to integrate directional information into various digital interactive experiences, or to use it as a basis to realize more complex shape and pattern haptic perception, providing new functions for the development of haptic experience.

[0037] 3) This invention proposes a system solution for sensing direction ultrasonic tactile experience that integrates gesture recognition. Its simple structure and complete functions make it easier to integrate into various contactless experiences. It is very suitable for providing implicit tactile cues for contactless activation solutions in various public service application scenarios, such as opening and closing doors, faucets, flushing toilets, and making payments. This can reduce the spread of diseases during use and is a more hygienic solution. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the system structure according to an embodiment of the present invention;

[0039] Figure 2 This is a schematic diagram of the control strategy for ultrasonic tactile sensing used to sense direction in an embodiment of the present invention;

[0040] Figure 3 This is a system control logic flowchart of an embodiment of the present invention.

[0041] In the diagram: 1-Host computer; 2-Support and bus; 3-Main controller; 4-Distance sensor; 5-Haptic feedback area; 6-User interaction hand; 7-Haptic point; 8-Ultrasonic transducer array; 9-Signal generator. Detailed Implementation

[0042] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0043] It should be noted that the following detailed descriptions are exemplary and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0044] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0045] like Figure 1 As shown, this embodiment provides a system for sensing direction based on phased array ultrasonic tactile feedback, including:

[0046] Host computer 1 is used to send haptic mode control commands that can sense direction;

[0047] Distance sensor 4 is used to acquire hand position information as a basis for judging the system status;

[0048] The main controller 3 is used to extract the tactile mode control parameters from the received instructions and calculate the corresponding time delay and modulation information, process the hand position information as the basis for the system status, and make corresponding adjustments to the system status display and tactile mode output.

[0049] Signal generator 9 is used to convert the received phase delay and modulation information into drive signals for each transmission channel;

[0050] The ultrasonic transducer array 8 is used to continuously emit ultrasonic waves according to the drive signal, and control the sound field distribution of the target area in real time to generate directional tactile feedback.

[0051] The bracket and bus 2 are 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 the components of the system.

[0052] The distance sensor 4 is connected to the main controller 3, which detects the position information of the user's hand in real time and sends it to the main controller for processing, thereby serving as the basis for judging the state of the haptic interaction system.

[0053] The main controller 3 is connected to the distance sensor 4, the signal generator 9, and the host computer 1 respectively. It receives the haptic mode control command with perceptible direction sent by the host computer, extracts the haptic mode control parameters in the command, calculates the corresponding phase delay and modulation information, and then sends it to the signal generator. The main controller also processes the information from the distance sensor, adjusts the system status and haptic mode output in real time according to the system settings, and provides auxiliary functions for system status display and recovery.

[0054] The signal generator 9 is connected to the main controller 3. Based on the phase delay and modulation signal information sent by the main controller, it calculates and generates the corresponding drive signal for each transmission channel, and amplifies the signal to excite the ultrasonic transducer array.

[0055] The ultrasonic transducer array 8 is connected to the signal generator 9 and is continuously excited by the drive 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 stay at different positions along the specified direction for a period of time, creating ultrasonic tactile feedback that allows the user to perceive the direction.

[0056] In the bracket and bus 2, the bracket sets the distance sensor and the ultrasonic transducer array in a centrally opposite position 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.

[0057] Figure 1 In the diagram, 5 represents the adjustable tactile feedback area with a certain range set by the system; 6 represents the user's interactive hand; and 7 represents the tactile point generated by modulated ultrasonic waves and can be manipulated by a set control strategy to give the user a sense of direction.

[0058] The host computer software 1 stores tactile commands pointing in different directions. The commands include parameters such as the height of the target area, the spatial position of the tactile point movement, and the time interval. In terms of usage, tactile commands in the corresponding direction can be sent according to the specific situation, and tactile commands in different directions can also be sent continuously in a certain order to adapt to more contactless application scenarios.

[0059] The haptic 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 it can be flexibly combined with different virtual experience systems.

[0060] The tactile point 7 is the focal point of the phased array ultrasound waves after amplitude modulation, and it is also the basic unit for ultrasonic tactile design to achieve direction perception, such as... Figure 2 As shown, this invention provides a control strategy for ultrasonic haptic feedback for direction perception. The palm area of ​​the human hand is used as the target area for haptic feedback. Two positions are set as the two endpoints representing the direction pointer. Single-point focused haptic feedback is used at the initial endpoint, and multi-point focused haptic feedback is generated at the final endpoint using a multi-point phase algorithm. At the same time, the duration of the haptic feedback at both endpoints and the switching time of the focus group are precisely controlled. Ultrasonic haptic feedback for the user to perceive direction is realized by controlling the movement mode of the haptic focus group.

[0061] This invention addresses the current lack of a high-performance, simple, highly scalable, and convenient external hand input detection solution for relatively simple ultrasonic haptic applications. It proposes a method based on a distance sensor and microcontroller, combined with a state machine design pattern, to achieve three one-dimensional gesture recognitions within a designated target area. This can be integrated into the ultrasonic haptic interaction system as a trigger condition for external input detection. Furthermore, it addresses the lack of rendering direction awareness in ultrasonic haptic design by proposing a novel control strategy for rendering direction-aware ultrasonic haptics. This strategy involves precisely controlling the dynamic switching of single-focus to multi-focus motion modes. A complete control scheme for rendering direction-aware ultrasonic haptics is provided, and based on this, a system for experiencing direction-aware ultrasonic haptic feedback is proposed.

[0062] (a) Implementation of detecting hand position to obtain hand position information

[0063] First, a detection area for tactile interaction is set above the ultrasonic transducer array, consisting of two distance intervals at different heights parallel to the array plane. Then, the height position information of the target user's hand relative to the ultrasonic transducer array plane is detected in real time by a distance sensor. Finally, the data is filtered by a recursive averaging algorithm in the main controller to obtain more stable position data that meets the requirements of acceptable delay.

[0064] Then, using a state machine design pattern, four identifiable hand states are constructed based on the real-time positional relationship between the hand and the detection area: idle state, single-click state, double-click state, and long-press state. Each of the four states has its own identifier for subsequent use by the system. In the main controller, the system first determines whether to switch from the idle state to one of the other three states by judging whether the real-time position of the hand intersects with the detection area. When an intersection is detected, a software timer is used to obtain the length of time the hand stays in the detection area, thereby distinguishing whether to switch to the long-press state or one of the other two states. Then, by setting a timer with a fixed time interval, the system determines whether to switch to the single-click state or double-click state by judging the number of times the intersection is detected within this interval. At the same time, after switching to the single-click state or double-click state, the system will immediately switch back to the idle state, while the long-press state will remain until the user's hand leaves the detection area before switching back to the idle state.

[0065] Finally, the filtered hand position data is input into the state machine, where three types of one-dimensional gesture recognition inputs from the user are detected. Different gestures are then used as trigger conditions for different functions of the system.

[0066] (II) Implementation of the control strategy for rendering direction-aware ultrasonic haptics

[0067] First, the control strategy of the ultrasonic phased array for the direction pointer presented in the palm area is written into the host computer. Then, the host computer calculates and converts it into various control parameters of the first and last ends of the direction pointer, including focusing mode, modulation frequency, focusing time period, and spatial coordinates of the focal point.

[0068] Then, the host computer edits the control parameters into instructions and sends them to the main controller via serial port. After the main controller waits for the instructions to be received, it stores them in the system buffer. Then, it identifies and verifies the validity of the received instructions to prevent illegal instruction input. Then, it extracts the parameters from the verified instructions and converts them into system control parameters for the directional sensing tactile feedback ultrasonic phased array.

[0069] The main controller embeds phase algorithms for multi-point and single-point focusing, algorithms for converting amplitude modulation frequency into clock count values, and software timers for controlling the focusing duration period. By inputting corresponding parameters into the corresponding algorithms, the phase delay and modulation control information of the first and last focus groups of the direction pointer are obtained. Then, the system timer is used to precisely control the focusing time period of the first and last ends and the switching time of the end focus group. Based on the obtained information and functions, the embedded system of the main controller first transmits information to control the first end to continuously perform single-point focusing for a specified time limit. Then, when the system time reaches the first and last end switching time point, information is transmitted again to control the last end to continuously perform multi-point focusing for a specified time limit and position. By completing the transmission conversion of control information for different tactile focus groups of the first and last ends within the constrained time limit, the signal generator generates corresponding signals based on the received data to excite the ultrasonic array to emit ultrasonic waves, thus completing a directional ultrasonic tactile feedback within the target area.

[0070] (III) Realization of directional perception and tactile experience

[0071] The three recognizable one-dimensional gestures implemented in (I) – single click, double click, and long press – are used as trigger gestures for system activation, system deactivation, and system haptic feedback state, respectively, ensuring that the target user's hand correctly remains within the detection area when the system is activated. Then, the ultrasonic haptic control strategy for direction perception implemented in (II) is used to apply the user-defined directional haptic feedback. The entire haptic experience control process is scheduled by the embedded system of the main controller, with system indicator lights and buttons used to assist in displaying and switching system states.

[0072] like Figure 3 As shown, the control logic of the phased array ultrasonic tactile sensing direction system provided in this embodiment is as follows:

[0073] First, the system power is turned on. The system initializes the hardware and software 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 lights 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.

[0074] Then, the distance sensor detects the target user's hand position in real time to determine whether the target user has made a click gesture. If so, the system initializes the parameters and the haptic experience officially begins; otherwise, it waits until the user makes a click gesture.

[0075] Based on this, it continues to determine 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 at the same time, the host computer software sends the first instruction of the haptic instruction sequence to the main controller. The main controller uses a phase optimization algorithm to calculate the phase delay of the haptic point to be generated, and sends it along with the modulation information to the signal generator continuously according to the set control strategy. If not, it waits for the user to use a long press gesture.

[0076] The signal generator processes the continuously received phase delay and modulation information to generate a drive signal for each ultrasonic transducer channel, which continuously excites the ultrasonic transducer array, thereby inducing the user to generate directional perception by controlling the motion mode of the tactile focus group as a direction pointer in the tactile interaction area.

[0077] Each time a tactile interaction is completed, the system will detect whether the user's hand has left the tactile interaction area. If not, the system will change the direction of the tactile perception mode and generate the corresponding tactile command, and the system will continue to be in the interactive state. If the hand has left the interactive state, the system will enter the sleep state and the system status indicator will switch to the initial state.

[0078] Then it determines whether the target user has performed a double-tap gesture. If not, it waits for the main controller's button function to restore the system for the next round of tactile interaction. If so, it declares the end of this round of directional tactile experience.

[0079] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A system for sensing direction using phased array ultrasonic tactile feedback, characterized in that, include: The host computer is used to send haptic control commands that can sense direction. A distance sensor is used to acquire hand position information as a basis for judging the system status; The main controller is used to extract the haptic mode control parameters from the received instructions and calculate the corresponding time delay and modulation information, process the hand position information as the basis for the system status, and make corresponding adjustments to the system status display and haptic mode output. A signal generator is used to convert the received phase delay and modulation information into drive signals for each transmission channel; An ultrasonic transducer array is used to continuously emit ultrasonic waves according to a drive signal, and control the sound field distribution of the target area in real time to generate directional tactile feedback. The system includes a support bracket and a bus, where the support bracket ensures that the distance sensor and the ultrasonic transducer array are in a suitable relative position, and the bus is used to transmit control signals between the various components of the system. The implementation method of the control strategy for ultrasonic haptics used to sense direction is as follows: First, the control strategy of the ultrasonic phased array for the direction pointer presented in the palm area is written into the host computer. Then, the host computer calculates and converts it into various control parameters of the first and last ends 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 serial port. After the main controller waits for the instructions to be received, it stores them in the system buffer. Then, it identifies and verifies the validity of the received instructions to prevent illegal instruction input. Then, it extracts the parameters from the verified instructions and converts them into system control parameters for the directional sensing tactile feedback ultrasonic phased array. The main controller embeds phase algorithms for multi-point and single-point focusing, algorithms for converting amplitude modulation frequency into clock count values, and software timers for controlling the focusing duration period. By inputting corresponding parameters into the corresponding algorithms, the phase delay and modulation control information of the first and last focus groups of the direction pointer are obtained. Then, the system timer is used to precisely control the focusing time period of the first and last ends and the switching time of the end focus group. Based on the obtained information and functions, the embedded system of the main controller first transmits information to control the first end to continuously perform single-point focusing for a specified time limit. Then, when the system time reaches the first and last end switching time point, information is transmitted again to control the last end to continuously perform multi-point focusing for a specified time limit and position. By completing the transmission conversion of control information for different tactile focus groups of the first and last ends within the constrained time limit, the signal generator generates corresponding signals based on the received data to excite the ultrasonic array to emit ultrasonic waves, thus completing a directional ultrasonic tactile feedback within the target area.

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

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

4. The system for direction sensing based on phased array ultrasonic tactile perception according to claim 1, characterized in that, The signal generator is connected to the main controller. Based on the phase delay and modulation signal information sent by the main controller, it calculates and generates the corresponding drive signal for each transmission channel, and amplifies the signal to excite the ultrasonic transducer array.

5. A system for sensing direction based on phased array ultrasonic tactile perception according to claim 1, characterized in that, The ultrasonic transducer array is connected to the signal generator and is continuously excited by the drive 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 stay at different positions along the specified direction for a period of time, creating ultrasonic tactile feedback that allows the user to perceive direction.

6. The system for direction sensing based on phased array ultrasonic tactile perception according to claim 1, characterized in that, The bracket positions the distance sensor and the ultrasonic transducer array in a centrally opposite manner 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. A system for sensing direction based on phased array ultrasonic tactile perception according to claim 1, characterized in that, The method for detecting hand position to obtain hand position information is as follows: First, a detection area for tactile interaction is set above the ultrasonic transducer array, consisting of two distance intervals at different heights and parallel to the array plane. Then, the height position information of the target user's hand relative to the ultrasonic transducer array plane is detected in real time by a distance sensor. Finally, the data is filtered by a recursive averaging algorithm in the main controller to obtain more stable position data that meets the requirements of acceptable delay. Then, using a state machine design pattern, four identifiable hand states are constructed based on the real-time positional relationship between the hand and the detection area: idle state, single-click state, double-click state, and long-press state. Each of the four states has its own identifier for subsequent use by the system. In the main controller, the system first determines whether to switch from the idle state to one of the other three states by judging whether the real-time position of the hand intersects with the detection area. When an intersection is detected, a software timer is used to obtain the length of time the hand stays in the detection area, thereby distinguishing whether to switch to the long-press state or one of the other two states. Then, by setting a timer with a fixed time interval, the system determines whether to switch to the single-click state or double-click state by judging the number of intersection detections within this interval. After switching to the single-click state or double-click state, the system immediately switches back to the idle state, while the long-press state is maintained until the user's hand leaves the detection area before switching back to the idle state. Finally, the filtered hand position data is input into the state machine, where three types of one-dimensional gesture recognition inputs from the user are detected. Different gestures are then used as trigger conditions for different functions of the system.

8. A system for sensing direction based on phased array ultrasonic tactile perception according to claim 1, characterized in that, The method for achieving directional tactile experience is as follows: Using three recognizable one-dimensional gestures—single, double, and long press—as trigger gestures for system on, system off, and system in haptic feedback state, respectively, the system ensures that the target user's hand is correctly positioned within the detection area when the system is on. Then, an ultrasonic haptic control strategy for sensing direction is used to apply the user's set directional haptic feedback. The entire haptic experience control process is scheduled by the embedded system of the main controller, and system indicator lights and buttons are used to assist in displaying and switching system states.

9. A system for sensing direction based on phased array ultrasonic tactile perception according to claim 1, characterized in that, The control logic of this system is as follows: First, the system power is turned on. The system initializes the hardware and software 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 lights 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 detects the target user's hand position in real time to determine whether the target user has made a click gesture. If so, the system initializes the parameters and the haptic experience officially begins; otherwise, it waits until the user makes a click gesture. Based on this, it continues to determine 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 at the same time, the host computer software sends the first instruction of the haptic instruction sequence to the main controller. The main controller uses a phase optimization algorithm to calculate the phase delay of the haptic point to be generated, and sends it along with the modulation information to the signal generator in accordance with the set control strategy. If not, it waits for the user to use a long press gesture. The signal generator processes the continuously received phase delay and modulation information to generate a drive signal for each ultrasonic transducer channel, which continuously excites the ultrasonic transducer array, thereby controlling the motion mode of the tactile focus group as a direction pointer in the tactile interaction area to induce the user to generate direction perception. Each time a tactile interaction is completed, the system will detect whether the user's hand has left the tactile interaction area. If not, the system will change the direction of the tactile perception mode and generate the corresponding tactile command, 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 it determines whether the target user has performed a double-tap gesture. If not, it waits for the main controller's button function to restore the system for the next round of tactile interaction. If so, it declares the end of this round of directional tactile experience.

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