A method and system for three-dimensional vibrotactile signal compression and transmission

Abstract

This invention discloses a method and system for compressing and transmitting three-dimensional vibration tactile signals, belonging to the field of human-computer interaction technology. The method includes: S1, sampling the three-dimensional vibration of an object surface using a sensor to obtain the time-domain coordinates of the three-dimensional vibration tactile signal; S2, constructing a three-dimensional perception dead zone model: calculating the current signal S... t =(x t ,y t ,z t The geometric distance L between the reference signal S0 = (x0, y0, z0) and the data source is determined. If L exceeds the dynamic threshold TS, data transmission is triggered; otherwise, the data is discarded. S3: The mapping relationship between the parameter DBP and the packet rate is dynamically adjusted by fitting a four-parameter logic curve model, and the rate budget s0 for the next time period is predicted based on the channel load. S4: Adaptive packet rate control. This invention provides a method and system for compressing and transmitting three-dimensional vibration tactile signals, which can effectively reduce the amount of transmitted data while maintaining high signal quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of human-computer interaction, and in particular to a three-dimensional vibration haptic signal compression and transmission method and system. BACKGROUND

[0002] Vibration haptic signals are a key source of information for human perception of physical environment surface texture and dynamic interaction, and play an important role in remote medical surgery robots, virtual reality interaction systems, industrial remote operation and other high-precision real-time control scenarios. For example, in remote surgery, doctors perceive the contact force of instruments and tissues through haptic feedback sensors; in industrial robot operation, haptic signals are used to accurately identify object materials and grasping force. With the advancement of three-dimensional haptic signal acquisition technology, its multi-dimensional characteristics have put forward higher requirements for transmission efficiency and signal quality.

[0003] Traditional haptic signal transmission technology is mostly based on one-dimensional signal design, using fixed perception thresholds and static compression strategies. The one-dimensional model cannot effectively capture the spatial directionality of three-dimensional signals, resulting in a significant decrease in perception quality when the signal is reconstructed. In addition, fixed thresholds are difficult to adapt to signal dynamics, and redundant data transmission exacerbates network load pressure; static rate control mechanisms are prone to data packet loss or delay under burst traffic, seriously affecting real-time interaction performance. Although some studies have attempted to introduce dynamic threshold optimization methods, they do not adjust in coordination with three-dimensional signal characteristics and channel load, making it difficult to balance compression efficiency and signal quality, limiting their practicality in complex scenarios. SUMMARY

[0004] The present application aims to provide a three-dimensional vibration haptic signal compression and transmission method and system to solve the problem that the existing haptic signal transmission method is only based on one-dimensional data processing, fixed perception thresholds and static compression strategies, which cannot fully capture the multi-dimensional characteristics of three-dimensional vibration haptic signals, and lacks real-time adaptive adjustment capability when network load changes dramatically, resulting in high data redundancy, poor real-time performance, large transmission delay and low signal reconstruction quality in high-precision real-time control scenarios such as remote medical treatment, virtual reality and industrial remote operation.

[0005] To achieve the above-mentioned purpose, the present application provides a three-dimensional vibration haptic signal compression and transmission method, comprising the following steps:

[0006] S1, sampling the three-dimensional vibration of the object surface using a sensor to obtain a three-dimensional vibration haptic signal time domain coordinate containing x, y and z direction components;

[0007] S2, constructing a three-dimensional perception dead zone model: based on a three-dimensional spherical region, dynamically determining the significance of signal changes, calculating the current signal S t =(x ty t ,z t geometric distance L with a reference signal S0=(x0,y0,z0), if L exceeds a dynamic threshold TS, data transmission is triggered, otherwise data is discarded;

[0008] S3, dynamic threshold optimization: a four-parameter logistic curve model is used to fit the mapping relationship between the dynamic adjustment parameter DBP and the packet rate, the rate budget s0 of the next period is predicted in combination with the channel load condition, and the optimal DBP is calculated reversely;

[0009] S4, adaptive packet rate control: the signal is segmented according to a preset period, the transmission parameter is independently adjusted in each period based on the target rate R0, and the signal consistent in objective quality with the original three-dimensional vibration haptic signal is restored, and the extended perceptual mean square error is used as the signal quality evaluation standard.

[0010] Preferably, the calculation formula of the geometric distance L in step S2 is:

[0011]

[0012] The calculation formula of the dynamic threshold TS is:

[0013] TS=DBP·||S0||;

[0014] wherein, is the amplitude of the reference signal.

[0015] Preferably, the four-parameter logistic curve model in step S3 is:

[0016]

[0017] wherein, b and c are fitting parameters optimized by the least square method.

[0018] Preferably, in step S3, the prediction formula of the rate budget s0 of the next period is:

[0019]

[0020] wherein, s -1 ,s -2 ,s -3 are the actual packet rates of the previous three periods; R0 is a preset target packet rate.

[0021] Preferably, in step S4, the evaluation formula of the signal quality Q is:

[0022] Q=100·exp(k q ·pmse);

[0023] wherein, k qis a preset constant; pmse is an extended perceptual mean square error, which is calculated as follows:

[0024]

[0025]

[0026] wherein P x ,P y ,P z are the perceptual values of the three-dimensional signal in the x, y and z dimensions respectively, k p is a constant determined by experiment; N represents the total number of samples; respectively represent the differences in the x, y and z dimensions of the three-dimensional original signal and the decoded signal; s x ,s y ,s z respectively represent the signal intensities of the three-dimensional signal in the x, y and z dimensions; respectively represent the perceptual values of the decoded signal in the x, y and z dimensions; S is the minimum perceptible amplitude (set as 0.001).

[0027] Preferably, in step S4, the preset period is 200 ms, and the transmission parameters in each period are independently adjusted.

[0028] Preferably, the three-dimensional perceptual dead zone model in step S2 is an isotropic spherical region, and the radius thereof is controlled by the dynamic threshold TS.

[0029] The application further provides a haptic communication system applied to the three-dimensional vibration haptic signal compression and transmission method, which comprises a master device, a slave device and a haptic signal transmission device, the master device is connected with the slave device through a communication link to realize compression and transmission of three-dimensional haptic signals.

[0030] Preferably, the haptic signal transmission device comprises:

[0031] a signal acquisition module for acquiring three-dimensional haptic signals;

[0032] a compression module for compressing the acquired signals in real time;

[0033] a transmission module for dynamically adjusting transmission parameters based on a segmented adaptive packet rate control strategy and sending the compressed data to a remote receiving end;

[0034] a signal reconstruction module for decoding and reconstructing the transmission data at the receiving end to restore three-dimensional vibration haptic signals.

[0035] Therefore, the application has the following beneficial effects by adopting the three-dimensional vibration haptic signal compression and transmission method and system:

[0036] (1) By constructing a three-dimensional perception-based spherical dead zone model, the isotropic perception characteristics of the human body in three-dimensional space are fully utilized, only the effective signals exceeding the human perception range are transmitted, the data compression rate is greatly improved, the transmission data volume is reduced, and the network load pressure is effectively alleviated;

[0037] (2) A dynamic threshold optimization method is adopted, a nonlinear regression model and a target packet rate prediction are used to adjust the dynamic parameter DBP in real time, so that when the network environment changes, the system can still maintain stable transmission rate and high signal reconstruction quality;

[0038] (3) The segmented adaptive packet rate control strategy can independently adjust the transmission parameters according to the network status in each period, significantly reducing the packet loss and delay caused by burst traffic, and ensuring the real-time performance and robustness of the entire haptic communication system;

[0039] (4) In the signal reconstruction process, by using the evaluation mechanism of extended perception mean square error pmse and standardized signal quality Q, the system can accurately quantify the difference between the reconstructed signal and the original signal, providing a reliable basis for subsequent parameter adjustment and optimization of the system.

[0040] The technical solutions of the present application will be described in further detail below with the aid of the accompanying drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0041] Figure 1 A flowchart of a three-dimensional vibration haptic signal compression and transmission method according to the present application;

[0042] Figure 2 A three-dimensional perception dead zone model according to an embodiment of the present application, wherein (a) is a signal change not significant; (b) is a signal change significant;

[0043] Figure 3 A fitting result diagram of a four-parameter logistic curve model according to an embodiment of the present application;

[0044] Figure 4 A segmented adaptive packet rate control strategy according to an embodiment of the present application. DETAILED DESCRIPTION

[0045] The following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0046] Please refer to Figure 1A method for three-dimensional vibrotactile signal compression and transmission, comprising the following steps:

[0047] S1, using an acceleration sensor, a vibration sensor or other tactile sensor to sample the three-dimensional vibration of the object surface, obtaining a three-dimensional vibration tactile signal time domain coordinate containing x, y, z three direction components, which reflects the vibration characteristics of the object surface texture, friction and operation process, providing the original data basis for subsequent data compression and transmission. The sampling frequency can be selected as 10000Hz to ensure high-precision data acquisition. The collected signal is used as the original input for subsequent processing and compression transmission.

[0048] S2, according to the multi-dimensional perception characteristics of human body to the vibration tactile signal, a isotropic spherical perception dead zone model is constructed in three-dimensional space: first, set the last transmission signal as the reference signal S0=(x0,y0,z0), and the amplitude ||S0|| as the reference of human tactile perception. For the signal S t =(x t ,y t ,z t ) collected at the current time, the geometric distance L between the current signal and the reference signal is calculated by the Euclidean distance calculation formula, and the calculation formula is:

[0049]

[0050] Then, according to the human perception threshold theory and Weber's law, the dynamic threshold TS is determined by using the dynamic threshold calculation formula, and the calculation formula is:

[0051] TS=DBP·||S0||;

[0052] Among them, is the amplitude of the reference signal. DBP is a dynamic adjustment parameter, which reflects the minimum perceptible proportion of human body to signal change. If L exceeds the dynamic threshold TS, data transmission is triggered, otherwise the signal change is not significant, and the data at this moment can not be transmitted, as shown in Figure 2 .

[0053] S3, dynamic threshold optimization: the mapping relationship between the dynamic adjustment parameter DBP and the packet rate is fitted by a four-parameter logistic curve model, and the rate budget s0 of the next period is predicted combined with the channel load condition. The four-parameter logistic curve model is:

[0054]

[0055] Among them, A, B, C, D are parameters fitted by least squares method, x represents the current DBP value, and f(x) represents the corresponding average packet rate. It can be simplified as:

[0056]

[0057] where b and c are fitting parameters optimized by least square method, as shown in Figure 3 .

[0058] Further, according to the actual packet rate data of the previous three periods, the target rate s0 of the next period is predicted by a rate prediction formula or other statistical methods, and the optimal DBP value that meets the target rate requirement is reversely calculated, which will be used to update the dynamic threshold; the prediction formula of the rate budget s0 of the next period is:

[0059]

[0060] where s -1 ,s -2 ,s -3 are the actual packet rates of the previous three periods; R0 is the preset target packet rate.

[0061] S4, adaptive packet rate control: the entire transmission process is segmented according to the preset period (200 ms), and in each period, the system independently adjusts the transmission parameters, including the data packet size, sending interval and transmission priority, etc., according to the actual channel load and the target packet rate of the next period obtained in step S3, so that the number of data packets transmitted by the system in the entire period is kept near the preset target, as shown in Figure 4 . In each period, only the data whose signal change exceeds the dynamic threshold TS is packaged and transmitted, and the remaining data is discarded or accumulated and sent in the subsequent period to reduce data redundancy and alleviate network congestion. The packet data is transmitted to the remote receiving end through a limited or wireless communication link, and the receiving end reconstructs the received data packet by using interpolation, compensation and other signal recovery algorithms according to the reference signal information pre-stored in the signal reconstruction module and the latest dynamic threshold TS, and restores the signal highly consistent with the original three-dimensional vibration haptic signal in objective quality. To quantify the error between the reconstructed signal and the original signal, the extended perceptual mean square error pmse is used as the signal quality evaluation index, and its calculation method is:

[0062]

[0063] where ΔP i represents the difference between the reconstructed value and the original value of the i-th sampling point in the three-dimensional perception space, respectively represent the differences in x, y and z dimensions of the three-dimensional original signal and the decoded signal, and N is the total number of samples. The formula for converting pmse to signal quality Q is:

[0064] Q = 100 · exp(k q · pmse);

[0065] wherein, k q is a preset constant; when pmse approaches 0, Q approaches 100, and as pmse increases, Q gradually decreases.

[0066] Through the above steps, efficient compression and stable transmission of three-dimensional vibration haptic signals can be achieved under the premise of ensuring human perception effect, which greatly reduces the transmission data volume and ensures the objective quality of the reconstructed signals.

[0067] The embodiment also provides a haptic communication system, which is applied to the above-mentioned method for three-dimensional vibration haptic signal compression and transmission and comprises a master device, a slave device, a haptic signal transmission device, a communication device and a control terminal. The master device is used for collecting three-dimensional vibration haptic signals and performing preliminary preprocessing. The slave device is configured with the haptic signal transmission device and is used for receiving compressed data transmitted by the master device and performing signal reconstruction. The communication device is used for establishing a stable wired or wireless communication link between the master device and the slave device. The control terminal is used for monitoring and adjusting transmission parameters and system running states. In the embodiment, the three-dimensional haptic signals collected by the master device are transmitted to the slave device through the communication device after being compressed. The slave device presents haptic feedback information to an operator after restoring the original signals by using the haptic signal transmission device, thereby realizing remote interaction and control. The system is particularly suitable for high-precision real-time control fields such as remote medical treatment, virtual reality and industrial remote operation.

[0068] The haptic signal transmission device comprises:

[0069] The signal acquisition module is used for collecting three-dimensional haptic signals and converting the collected analog signals into digital signals.

[0070] The compression module is used for performing real-time compression on the collected signals according to the method of steps S3-S4.

[0071] The transmission module is used for dynamically adjusting transmission parameters based on a segmented adaptive packet rate control strategy and sending the compressed data to a remote receiving end.

[0072] The signal reconstruction module is used for decoding and reconstructing the transmission data at the receiving end, restoring the original signals by using a pre-stored reference signal and the latest dynamic threshold, and outputting the original signals for subsequent application. The modules can be interconnected through a high-speed data bus or a wireless communication link to realize collaborative work and ensure that the system has low latency and high stability.

[0073] Meanwhile, the embodiment also provides a machine-readable storage medium which stores executable instructions, and the executable instructions are executed by a processor to perform the above-mentioned method for three-dimensional vibration haptic signal compression and transmission.

[0074] Therefore, the application adopts the above-mentioned method and system for three-dimensional vibration tactile signal compression and transmission, has strong compatibility and applicability, can be widely applied to remote medical treatment, virtual reality, human-computer interaction, industrial remote operation and the like, and can flexibly adjust the sampling frequency, packet rate and dynamic threshold value parameters according to specific scenes, and meet high requirements on real-time performance and signal quality in different application scenes.

[0075] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them, although the present application has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that: it can still modify or equivalently replace the technical solutions of the present application, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present application.

Claims

1. A method for compressing and transmitting three-dimensional vibration tactile signals, characterized in that, Includes the following steps: S1. Use sensors to sample the three-dimensional vibration of the object surface to obtain the time-domain coordinates of the three-dimensional vibration tactile signal containing x, y, and z directional components; S2. Construct a three-dimensional sensing dead zone model: Based on the dynamic determination of the significance of signal changes within a three-dimensional spherical region, calculate the current signal S. t =(x t ,y t ,z t The geometric distance L between the reference signal S0 = (x0, y0, z0) and the reference signal S0 = (x0, y0, z0) is determined. If L exceeds the dynamic threshold TS, data transmission is triggered; otherwise, the data is discarded. S3. Dynamic Threshold Optimization: The mapping relationship between the parameter DBP and the packet rate is dynamically adjusted by fitting a four-parameter logistic curve model, and the rate budget s0 for the next time period is predicted in combination with the channel load condition, and the optimal DBP is calculated in reverse. The four-parameter logic curve model is as follows: Where b and c are both fitting parameters optimized by the least squares method; The prediction formula for the rate budget s0 in the next time period is: Among them, s -1 ,s -2 ,s -3 R0 represents the actual packet rate for the first three time periods; R0 represents the preset target packet rate. S4. Adaptive Packet Rate Control: The signal is divided into preset time periods. Within each time period, the transmission parameters are independently adjusted based on the target rate R0. Then, the signal is restored to be consistent with the original three-dimensional vibration tactile signal in terms of objective quality. Extended sensing mean square error is used as the signal quality evaluation standard.

2. The method for compressing and transmitting three-dimensional vibration tactile signals according to claim 1, characterized in that, The formula for calculating the geometric distance L in step S2 is: The formula for calculating the dynamic threshold TS is: TS = DBP·||S0||; in, The amplitude of the reference signal.

3. The method for compressing and transmitting three-dimensional vibration tactile signals according to claim 1, characterized in that, In step S4, the formula for evaluating signal quality Q is: Q=100·exp(k q ·pmse); Where, k q This is a preset constant; pmse is the extended sensing mean square error, which is calculated as follows: Among them, P x ,P y ,P z Let k be the perceived values ​​of the three-dimensional signal in the x, y, and z dimensions, respectively. p A constant determined experimentally; N represents the total sample size; These represent the differences between the original 3D signal and the decoded signal in the x, y, and z dimensions, respectively; s x s y s z These represent the signal strength of the three-dimensional signal in the x, y, and z dimensions, respectively. These represent the perceived values ​​of the decoded signal in the x, y, and z dimensions, respectively; S is the minimum perceptible amplitude.

4. The method for compressing and transmitting three-dimensional vibration tactile signals according to claim 1, characterized in that: In step S4, the preset time period is 200ms, and the transmission parameters are adjusted independently within each time period.

5. The method for compression and transmission of three-dimensional vibration tactile signals according to claim 1, characterized in that: The three-dimensional perception dead zone model in step S2 is an isotropic spherical region, the radius of which is controlled by the dynamic threshold TS.

6. A tactile communication system, applied to the method for three-dimensional vibration tactile signal compression and transmission as described in any one of claims 1-5, characterized in that, include: The system consists of a master device, a slave device, and a tactile signal transmission device. The master device is connected to the slave device via a communication link to achieve compressed transmission of three-dimensional tactile signals.

7. A tactile communication system according to claim 6, characterized in that, The tactile signal transmission device includes: Signal acquisition module: used to acquire three-dimensional tactile signals; Compression module: performs real-time compression on the acquired signals; Transmission module: Based on a segmented adaptive packet rate control strategy, it dynamically adjusts transmission parameters to send compressed data to the remote receiving end; Signal reconstruction module: Decodes and reconstructs the transmitted data at the receiving end to recover the three-dimensional vibration tactile signal.

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