Non-contact force haptic feedback system and method based on ultrasonic transducer array

Abstract

The application discloses a kind of non-contact force tactile feedback system and method based on ultrasonic transducer array, including ultrasonic transducer array, FPGA signal conversion and driving module, and data processing and control module being arranged on computer;Ultrasonic transducer array is composed of circuit board and shell;FPGA signal conversion and driving module signal output end is connected to the circuit board of ultrasonic transducer array;Data processing and control module are connected to the signal input end of FPGA signal conversion and driving module.The application designs a kind of non-contact force tactile feedback system, which can realize non-contact touch feeling and realize real-time automatic adjustment of ultrasonic focusing position, solves the problem that ultrasonic focusing point cannot be automatically tracked and adjusted according to the change of finger position in existing non-contact force tactile system.

Description

Technical Field

[0001] The present invention relates to the field of tactile feedback technology, and in particular to a non-contact force tactile feedback system and method based on an ultrasonic transducer array. Background Art

[0002] Ultrasonic phased array technology utilizes an array of multiple ultrasonic transmitters and receivers, controlling the phase and amplitude of each unit to achieve focused and directional transmission of ultrasound. Non-contact ultrasonic tactile feedback systems are a recently emerging human-computer interaction technology that utilizes ultrasonic phased array technology to provide tactile feedback to users without physical contact. Research on this technology aims to enhance the naturalness, convenience, and multisensory experience of human-computer interaction.

[0003] Existing ultrasonic tactile feedback systems can generate touch sensations for fingers at a fixed height, but the system cannot obtain the movement of the finger and therefore cannot automatically adjust the ultrasonic focus position to track the direction of the finger movement. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art. To achieve the above purpose, a non-contact force tactile feedback system and method based on an ultrasonic transducer array is adopted to solve the problems raised in the above background technology.

[0005] A non-contact force tactile feedback system based on an ultrasonic transducer array, comprising an ultrasonic transducer array, an FPGA signal conversion and drive module, and a data processing and control module arranged on a computer;

[0006] The ultrasonic transducer array consists of a circuit board and a housing;

[0007] The circuit board is provided with a plurality of array-distributed ultrasonic working array elements, which are composed of a plurality of ultrasonic sensor arrays and are capable of transmitting and receiving ultrasonic waves;

[0008] The ultrasonic working array element includes a first ultrasonic transducer unit and a second ultrasonic transducer unit distributed around the first ultrasonic transducer unit. Each ultrasonic transducer unit includes an ultrasonic sensor. The first ultrasonic transducer unit has the functions of transmitting and receiving ultrasonic waves, and the second ultrasonic transducer unit only has the function of transmitting ultrasonic waves. The first ultrasonic transducer unit and the second ultrasonic transducer unit are both embedded in the sound source hole provided in the housing.

[0009] The first ultrasonic transducer unit is located at the center of the ultrasonic working array element and is used to measure the distance from the skin surface to the array element center in real time;

[0010] The ultrasonic waves generated by the second ultrasonic transducer unit are used to form ultrasonic focusing, and non-contact tactile sensation is generated when the skin is contacted, and a different operating frequency is used than the first ultrasonic transducer unit;

[0011] When the ultrasonic transducer array is in operation, all the first ultrasonic transducer units on it work at the same time to measure the distance of the skin above the measuring unit, and the first ultrasonic transducer units transmit the distance measurement information to the computer, and the computer takes the lowest point of the measured skin as the focusing point of the ultrasonic waves emitted by the second ultrasonic transducer unit; when the finger moves, the computer adjusts the parameters of the second ultrasonic transducer unit to form a new focusing position according to the distance measurement information;

[0012] The signal output end of the FPGA signal conversion and driving module is connected to the circuit board of the ultrasonic transducer array;

[0013] The computer is connected to the signal input end of the FPGA signal conversion and driving module.

[0014] As a further technical solution of the application: the FPGA signal conversion and driving module is installed in a separate housing, and the two ends are connected to the ultrasonic transducer array and the computer.

[0015] As a further technical solution of the application: the data processing and control module provided on the computer is used for system control and ultrasonic parameter setting and adjustment.

[0016] As a further technical solution of the application: the signal output end of the FPGA signal conversion and driving module and the ultrasonic transducer array adopt a wired connection mode.

[0017] As a further technical solution of the application: the computer provided with the data processing and control module is connected to the signal input end of the FPGA signal conversion and driving module through a wireless connection or a wired connection.

[0018] Another technical solution: a method using the non-contact force tactile feedback system based on the ultrasonic transducer array of any one of the above, comprising the following steps:

[0019] Step S1, power on and start the non-contact force tactile feedback system based on the ultrasonic transducer array;

[0020] Step S2, initialize the data processing and control module and the FPGA signal conversion and driving module on the computer;

[0021] Step S3, input the frequency of the ultrasonic waves generated by the first ultrasonic transducer unit and the second ultrasonic transducer unit and the initial position of the focusing point on the data processing and control module, respectively;

[0022] Step S4: starting the ultrasonic transducer array, which generates ultrasonic waves according to input parameters and forms an ultrasonic focus in a predetermined area;

[0023] Step S5: placing a finger or palm above the ultrasonic transducer array;

[0024] Step S6: The first ultrasonic transducer unit detects the finger and transmits the distance measurement information to the system, and the system adjusts the parameters of the second ultrasonic transducer unit to form a new focal point at the lowest point of the skin;

[0025] Step S7: The finger continues to move downward through the focal point, and the computer determines that the finger has passed the ultrasonic focal point;

[0026] Step S8: The finger or palm moves, and the ultrasonic focus automatically follows the finger or palm to maintain a non-contact touch.

[0027] Compared with the prior art, the present invention has the following technical effects:

[0028] Using the above technical solution, a tactile feedback system was designed that not only provides non-contact tactile sensations but also detects finger position in real time and adjusts the ultrasonic focus position. The system primarily comprises an ultrasonic transducer array, an FPGA signal conversion and driver module, and a computer-based data processing and control module. It generates ultrasonic waves, forming a focal point, and receives reflected ultrasonic waves, performing real-time distance measurement of the finger above the ultrasonic transducer array and subsequently adjusting the ultrasonic focus position. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings:

[0030] Figure 1 This is a schematic structural diagram of a tactile feedback system according to an embodiment disclosed in this application;

[0031] Figure 2 Schematic diagram and plan view of the structure of the ultrasonic transducer array according to the embodiment disclosed in this application;

[0032] Figure 3 A plan view of a working element on an ultrasonic transducer array according to an embodiment disclosed in the present application and a schematic view of the working element generating ultrasonic waves and receiving echoes;

[0033] Figure 4 This is a schematic diagram of focusing the ultrasonic waves generated by the ultrasonic transducer array according to the embodiment disclosed in the present application when in operation.

[0034] Fig. 1: 1, ultrasonic transducer array; 2, FPGA signal conversion and driving module; 3, computer; 4, working element on the ultrasonic transducer array; 5, internal circuit board of the ultrasonic transducer array; 6, sound source hole; 7, ultrasonic transducer array shell; 8, first ultrasonic transducer unit; 9, second ultrasonic transducer unit. DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0036] Please refer to Figure 1 In the embodiments of the present application, a non-contact force haptic feedback system based on an ultrasonic transducer array includes an ultrasonic transducer array 1, an FPGA signal conversion and driving module 2, and a computer 3, wherein a data processing and control module is arranged on the computer 3.

[0037] In the present embodiment, the ultrasonic transducer array 1 is composed of a circuit board 5 and a shell 7 in structure, and the external features include a plurality of arrayed ultrasonic working elements 4.

[0038] In the present embodiment, the FPGA signal conversion and driving module 2 is placed in an external independent square box, and the signal output end of the FPGA signal conversion and driving module 2 is connected to the ultrasonic transducer array 1 in a wired manner.

[0039] In the present embodiment, the signal input end of the FPGA signal conversion and driving module 2 is connected to the computer 3 provided with a data processing and control program in a wireless or wired manner.

[0040] In the present embodiment, the data processing and control module on the computer 3 can artificially operate or automatically control the parameters of the ultrasonic transducer array 1 to generate ultrasonic waves and adjust the position of the focal point.

[0041] Please refer to Figure 2 In the present embodiment, the ultrasonic transducer array 1 is composed of a circuit board 5 and a shell 7 in structure, and the circuit board 5 contains a plurality of sensors for transmitting and receiving ultrasonic waves, the circuit board 5 is provided with a plurality of arrayed ultrasonic working elements 4, and 16 working elements 4 are arranged on the circuit board 5 in a symmetrical arrangement of 4 rows and 4 columns; the circuit board 5 is installed inside the shell 7 and connected to the signal output end of the FPGA signal conversion and driving module 2.

[0042] In this embodiment, the upper plate of the shell 7 of the ultrasonic transducer array is provided with sound source holes 6, and the sound source holes 6 are also arranged on the upper plate of the shell in a symmetrical arrangement of 4 rows and 4 columns. The ultrasonic working array element 4 on the internal circuit board includes a first ultrasonic transducer unit and a second ultrasonic transducer unit distributed in an array manner around the first ultrasonic transducer unit; the number of sound source holes is the same as that of the ultrasonic transducer unit, each sound source hole 6 corresponds to a first ultrasonic transducer unit or a second ultrasonic transducer unit, and the sound source hole and the ultrasonic transducer unit are embedded together.

[0043] Please refer to Figure 3 A working array element 4 on the ultrasonic transducer array consists of 9 ultrasonic transducer units, which are arranged symmetrically in 3 rows and 3 columns. The working array element includes two types of ultrasonic transducer units, each of which includes an ultrasonic sensor; the first ultrasonic transducer unit 8 contains an ultrasonic transmitter and receiver, which can transmit and receive ultrasonic waves and is located at the center of the working array element; the second ultrasonic transducer unit 9 can only transmit ultrasonic waves for focusing and is evenly distributed around the first ultrasonic transducer unit 8.

[0044] In this embodiment, the first ultrasonic transducer unit 8 and the second ultrasonic transducer unit 9 are both arranged on a circuit board inside the ultrasonic transducer array. The first ultrasonic transducer unit 8 transmits and receives ultrasonic waves for real-time measurement of the distance from the skin surface to the center of the array element.

[0045] In this embodiment, the second ultrasonic transducer unit 9 around the center of the array element emits ultrasonic waves, focusing on a certain position above the ultrasonic transducer array 1, producing a non-contact touch when the skin touches it, and adopts a different operating frequency from the first ultrasonic transducer unit.

[0046] In this embodiment, the first ultrasonic transducer unit can transmit and receive ultrasonic waves and is insensitive to the ultrasonic frequency transmitted by the second ultrasonic transducer unit;

[0047] The second ultrasonic transducer unit only transmits ultrasonic waves, does not receive ultrasonic echoes, and uses a different operating frequency from the first ultrasonic transducer unit;

[0048] Please refer to Figure 4, the ultrasonic transducer uses phased array technology, and the ultrasonic waves emitted by each second ultrasonic transducer unit can be set to have the same phase when reaching the touch point, thereby achieving superposition of ultrasonic waves at the touch point. When the ultrasonic transducer array is working, all the first ultrasonic transducer units on it work at the same time, measuring the distance to the skin above the unit. The first ultrasonic transducer unit transmits the ranging information to the computer, and the computer uses the measured lowest point of the skin as the focal point for the second ultrasonic transducer unit to emit ultrasonic waves; when the finger moves, the computer adjusts the parameters of the second ultrasonic transducer unit according to the ranging information to form a new focal position. The use of phased array technology enhances the signal at the touch point and enhances the sense of touch;

[0049] Working principle:

[0050] Please refer to Figure 1 , Figure 1 This is a schematic structural diagram of a tactile feedback system according to an embodiment disclosed in this application;

[0051] The operating principle of the ultrasonic tactile feedback system is based on the transmission and reception of ultrasonic waves, the conversion of electrical signals, and phase setting. First, the data processing and control module on computer 3 sets the parameters for the generation and transmission of ultrasonic waves by the first and second ultrasonic transducer units. These parameters define the frequency of ultrasonic waves generated by the ultrasonic transducer units and the coordinate parameters of the initial focal point formed by the second ultrasonic transducer unit's transmission of ultrasonic waves. After the ultrasonic transducer array is activated, computer 3 transmits the parameter information to FPGA signal conversion and drive module 2. FPGA signal conversion and drive module 2 converts the parameter information into drive signals for the sensors in the ultrasonic transducer units to generate and transmit ultrasonic waves. These signals include phase period, synchronous clock, and modulation signal. FPGA signal conversion and drive module 2 transmits the drive signals to the circuit board within the ultrasonic transducer array 1. The drive signals are amplified and accurately output by the circuit board to ensure that each working element on the circuit board operates according to the predetermined requirements.

[0052] The ultrasonic sensor of the second ultrasonic transducer unit on the circuit board receives the drive signal transmitted by the circuit board and generates ultrasonic waves according to predetermined parameters, focusing them in a specific area. The first ultrasonic transducer unit receives the drive signal, emits ultrasonic waves, and also receives its own ultrasonic echo reflected from the skin surface. The received echo signal is transmitted via the circuit board inside the ultrasonic transducer array to the FPGA signal conversion and drive module 2. After processing by the FPGA signal conversion and drive module 2, it is transmitted to the data processing and control module on the computer 3. When a person's finger or palm is placed above the ultrasonic transducer array, the first ultrasonic transducer unit detects the finger and transmits the distance measurement information to the system. The system then adjusts the parameters of the second ultrasonic transducer unit to form a focal point at the lowest point of the skin. As the finger or palm moves, the computer adjusts the position of the focal point based on the real-time detection of the finger's position.

[0053] Another technical solution is a method for using any of the above-mentioned non-contact force tactile feedback systems based on an ultrasonic transducer array, comprising the following steps:

[0054] Step S1, powering on and starting a non-contact force tactile feedback system based on an ultrasonic transducer array;

[0055] Step S2, initializing the data processing and control module and the FPGA signal conversion and driving module on the computer;

[0056] Step S3: inputting the frequency of the ultrasonic wave generated by the first ultrasonic transducer unit and the initial position of the focus point of the second ultrasonic transducer unit into the data processing and control module respectively;

[0057] Step S4: starting the ultrasonic transducer array, which generates ultrasonic waves according to input parameters and forms an ultrasonic focus in a predetermined area;

[0058] Step S5: placing a finger or palm above the ultrasonic transducer array;

[0059] Step S6: The first ultrasonic transducer unit detects the finger and transmits the distance measurement information to the system, and the system adjusts the parameters of the second ultrasonic transducer unit to form a new focal point at the lowest point of the skin;

[0060] Step S7: The finger continues to move downward through the focal point, and the computer determines that the finger has passed the ultrasonic focal point;

[0061] Step S8: The finger or palm moves, and the ultrasonic focus automatically follows the finger or palm to maintain a non-contact touch.

[0062] Although the embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents, and all should be included within the scope of protection of the present invention.

Claims

1. A non-contact force tactile feedback system based on an ultrasonic transducer array, characterized in that: It includes an ultrasonic transducer array, an FPGA signal conversion and driving module, and a data processing and control module set on a computer; The ultrasonic transducer array consists of a circuit board and a housing; The circuit board is provided with a plurality of array-distributed ultrasonic working array elements, which are composed of a plurality of ultrasonic sensor arrays and are capable of transmitting and receiving ultrasonic waves; The ultrasonic working array element includes a first ultrasonic transducer unit and a second ultrasonic transducer unit distributed around the first ultrasonic transducer unit. Each ultrasonic transducer unit includes an ultrasonic sensor. The first ultrasonic transducer unit has the functions of transmitting and receiving ultrasonic waves, and the second ultrasonic transducer unit only has the function of transmitting ultrasonic waves. The first ultrasonic transducer unit and the second ultrasonic transducer unit are both embedded in the sound source hole provided in the housing. The first ultrasonic transducer unit is located at the center of the ultrasonic working array element and is used to measure the distance from the skin surface to the array element center in real time; The ultrasonic wave generated by the second ultrasonic transducer unit is used to form an ultrasonic focus, which produces a non-contact tactile sensation when the skin comes into contact with the ultrasonic wave, and uses a different operating frequency from that of the first ultrasonic transducer unit; When the ultrasonic transducer array is in operation, all first ultrasonic transducer units thereon operate simultaneously to measure the distance to the skin above the unit. The first ultrasonic transducer unit transmits the distance measurement information to the computer, and the computer uses the measured lowest point of the skin as the focal point for the second ultrasonic transducer unit to transmit the ultrasonic wave. When the finger moves, the computer adjusts the parameters of the second ultrasonic transducer unit according to the distance measurement information to form a new focal position. The signal output end of the FPGA signal conversion and driving module is connected to the circuit board of the ultrasonic transducer array; The computer is connected to the signal input end of the FPGA signal conversion and driving module.

2. The non-contact force tactile feedback system based on an ultrasonic transducer array according to claim 1, characterized in that: The FPGA signal conversion and driving module is installed in an independent shell, and its two ends are connected to the ultrasonic transducer array and the computer.

3. The non-contact force tactile feedback system based on an ultrasonic transducer array according to claim 1, characterized in that: The data processing and control module provided on the computer is used for performing system control and setting and adjusting ultrasonic parameters.

4. The non-contact force tactile feedback system based on an ultrasonic transducer array according to claim 1, characterized in that: The signal output end of the FPGA signal conversion and driving module and the ultrasonic transducer array are connected by wire.

5. The non-contact force tactile feedback system based on an ultrasonic transducer array according to claim 4, characterized in that: The computer provided with the data processing and control module is connected to the signal input end of the FPGA signal conversion and driving module through a wireless connection or a wired connection.

6. A method using a non-contact force tactile feedback system based on an ultrasonic transducer array according to any one of claims 1 to 5, characterized in that: The following steps are involved: Step S1, powering on and starting a non-contact force tactile feedback system based on an ultrasonic transducer array; Step S2, initializing the data processing and control module and the FPGA signal conversion and driving module on the computer; Step S3: inputting the frequency of the ultrasonic wave generated by the first ultrasonic transducer unit and the initial position of the focus point of the second ultrasonic transducer unit into the data processing and control module respectively; Step S4: starting the ultrasonic transducer array, which generates ultrasonic waves according to input parameters and forms an ultrasonic focus in a predetermined area; Step S5: placing a finger or palm above the ultrasonic transducer array; Step S6: The first ultrasonic transducer unit detects the finger and transmits the distance measurement information to the system, and the system adjusts the parameters of the second ultrasonic transducer unit to form a new focal point at the lowest point of the skin; Step S7: The finger continues to move downward through the focal point, and the computer determines that the finger has passed the ultrasonic focal point; Step S8: The finger or palm moves, and the ultrasonic focus automatically follows the finger or palm to maintain a non-contact touch.

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