CN-121987951-A - Self-adaptive functional electrical stimulation system based on bimodal feedback and control method

CN121987951ACN 121987951 ACN121987951 ACN 121987951ACN-121987951-A

Abstract

The invention relates to the technical field of medical rehabilitation and discloses a self-adaptive functional electrical stimulation system based on bimodal feedback and a control method. The system comprises a main control module, a stimulation output module, a nerve electric signal detection module, a biological impedance test module and a safety isolation module. The main control module comprises a safe current determining unit, a stimulation control unit and a dynamic calibration unit, which are respectively used for determining an individualized initial safe current based on nerve action potential feedback, controlling treatment stimulation output and dynamically calibrating the upper limit of the safe current according to biological impedance changes before and after stimulation. According to the invention, through bimodal feedback of the nerve electric signal and the biological impedance, individuation calibration and real-time dynamic optimization of the stimulation parameters are realized, the problems that the traditional functional electric stimulation depends on experience setting and the treatment effect and safety caused by lack of physiological feedback are difficult to ensure are solved, and the accuracy, safety and adaptability of rehabilitation therapy are remarkably improved.

Inventors

ZHANG GUANGJU
MA MINGHUI
YANG XIAOLI
QI RENLONG
ZHAO XIJUN
YANG KUN
MENG LIN
SUN SHIRU
LI DAHAI

Assignees

郑州科技学院

Dates

Publication Date: 20260508
Application Date: 20260129

Claims (10)

1. An adaptive functional electrical stimulation system based on bimodal feedback, comprising: the main control module is used for executing control logic; The stimulation output module is used for generating and outputting electric stimulation pulses according to the control of the main control module; a nerve electrical signal detection module for detecting a nerve action potential signal induced by the electrical stimulation pulse; the biological impedance testing module is used for measuring the impedance of biological tissues before and after the output of the electric stimulation pulse; The safety isolation module is connected between the stimulation output module and the human body electrode and is used for realizing electric isolation; Wherein, the main control module includes: The safe current determining unit is used for controlling the stimulation output module to output a series of stimulation pulses with increasing amplitude, and determining the corresponding stimulation pulse current amplitude as initial safe current when the nerve action potential is induced for the first time based on the feedback of the nerve electric signal detecting module; A stimulation control unit for controlling the stimulation output module to output a therapeutic stimulation based on the initial safe current; The dynamic calibration unit is used for controlling the biological impedance test module to respectively acquire a first biological impedance value and a second biological impedance value before and after outputting single treatment stimulation, and carrying out real-time calibration on the initial safe current according to the variation of the first biological impedance value and the second biological impedance value so as to update the current amplitude safety upper limit of the subsequent treatment stimulation.
2. The electrical stimulation system of claim 1, wherein the dynamic calibration unit is configured to: When the increase of the second bio-impedance value relative to the first bio-impedance value exceeds a safety-priority positive threshold When the safety current upper limit is lower than the safety current upper limit, generating a down-regulating instruction; When the increase is negative and its absolute value exceeds a negative threshold for performance optimization When the safety current upper limit is not exceeded, an up-regulating instruction is generated to increase the safety current upper limit.
3. The electrical stimulation system according to claim 1, wherein the safety current determination unit is configured to determine the initial safety current using an iterative incremental algorithm, which satisfies the relation: Wherein The excitation pulse current amplitude for the kth output, Increasing the step length for the preset current, and continuing the iterative process until the induced neural action potential amplitude is detected , Is a preset threshold voltage.
4. The electrical stimulation system of claim 1, wherein the stimulation output module comprises: The input end of the digital-to-analog converter is connected with the main control module and is used for receiving digital control signals; The control end of the voltage-controlled constant current source is connected with the output end of the digital-to-analog converter; And the power amplifying circuit is connected between the output end of the voltage-controlled constant current source and the safety isolation module.
5. The electro-stimulation system of claim 1, wherein the nerve electrical signal detection module comprises a low noise preamplifier, a band pass filter and an analog-to-digital converter connected in sequence, wherein the band pass range of the band pass filter is set to 10Hz to 3000Hz.
6. The electrical stimulation system of claim 1, wherein the bioimpedance testing module employs a four electrode measurement method comprising: A test signal generator for injecting an alternating current test signal into the biological tissue through the first electrode; A voltage measuring unit for measuring a response voltage generated on the biological tissue through the second electrode pair; And the impedance calculating unit is used for calculating the impedance value of the biological tissue according to the test signal and the response voltage.
7. The electrical stimulation system of claim 1, wherein the safety isolation module comprises: The signal isolation unit is connected between the control ends of the main control module and the stimulation output module by adopting a photoelectric coupler; And the power isolation unit adopts an isolated DC-DC converter and is used for providing isolated driving voltage for the stimulation output module.
8. A method for controlling adaptive functional electrical stimulation based on bimodal feedback, characterized in that it comprises the following steps: S1, a safety starting point determining stage, wherein the stimulation output module is controlled to output a series of stimulation pulses with increasing amplitude, and the corresponding current amplitude is determined to be initial safety current when the nerve action potential is induced for the first time based on the feedback of the nerve electric signal detection module; s2, pre-treatment reference measurement, wherein before the treatment stimulus is output, the biological impedance testing module is controlled to obtain a first biological impedance value; S3, outputting therapeutic stimulation, namely controlling the stimulation output module to output the therapeutic stimulation in a way that the amplitude of the initial safe current is not exceeded; S4, measuring a state after treatment, namely controlling the biological impedance testing module to acquire a second biological impedance value after the treatment stimulation is finished; And S5, dynamically calibrating the initial safe current based on the variation of the second biological impedance value and the first biological impedance value, and taking the calibrated value as a new safe current upper limit of the next treatment cycle.
9. The control method according to claim 8, wherein in step S5, the dynamic calibration includes calculating an impedance variation amount Wherein For the value of the second bioimpedance, Is a first bioimpedance value; If it is Then press Down-regulating the safety current; If it is And the present safety current is below the absolute upper safety limit Then press Up-regulating the safety current; Wherein, the A positive threshold value for safety priority, The negative threshold is optimized for the performance, 、 Is a preset adjustment coefficient.
10. The control method according to claim 8, wherein in step S1, the nerve action potential is detected by iteratively increasing the amplitude of the excitation pulse and simultaneously until the peak voltage of the nerve action potential reaches or exceeds a preset response threshold voltage Thereby determining the initial safe current.

Description

Self-adaptive functional electrical stimulation system based on bimodal feedback and control method Technical Field The invention relates to the technical field of medical rehabilitation, in particular to a self-adaptive functional electrical stimulation system based on bimodal feedback and a control method. Background The functional electrical stimulation technology excites neuromuscular activity through external current pulses, and is widely applied to the fields of cerebral apoplexy rehabilitation, functional reconstruction after spinal cord injury, pain management and the like. With the development of clinical practice, therapeutic goals have gradually turned from inducing basal muscle contractions to precise reconstructions of complex, fine, and personalized functional activities. This trend places higher demands on stimulation devices, in that the treatment parameters need to be matched with the individual physiological characteristics of the patient not only at the initial stage of treatment, but also in response to the dynamic changes of tissue states induced by electrical stimulation in real time during the course of continuous treatment, so as to achieve a long-term optimal balance of safety and efficacy. Currently, the parameter setting of the traditional functional electrical stimulation system mostly depends on the experience of operators, and lacks of real-time physiological signal feedback, so that the safety margin and the effective dosage of treatment are difficult to objectively guarantee. Specifically, two progressive core problems are faced in clinic, namely, how to objectively and individually determine a safe stimulation current starting point which can reliably activate a target nerve channel and cannot cause tissue injury or discomfort in the initial stage of treatment, and how to monitor local tissue physiological state change caused by electric stimulation in real time in the continuous treatment process and dynamically adjust output parameters according to the local tissue physiological state change so as to maintain the consistency of treatment response and avoid accumulated risks. In the prior art, although the existing devices integrate myoelectricity, electrocardiograph or electroencephalogram and other biological signal feedback mechanisms for realizing parameter adjustment, the feedback signals are mostly used for evaluating the overall physiological state, such as anesthesia depth, pain level or sleep stage, and the control logic and the closed-loop control requirement for accurate dose adjustment based on real-time physiological response of local tissues, which are required by functional electrical stimulation, have essential differences. Disclosure of Invention In order to solve the problems that in the prior art, functional electrical stimulation equipment lacks a closed-loop regulation mechanism interacting with a treatment part in real time, so that treatment parameters are insufficient in individuation, safety depends on experience, tissue state changes cannot be dynamically tracked and responded, and the like, the invention provides a self-adaptive functional electrical stimulation system based on bimodal feedback and a control method. The method comprises the steps of establishing a safe starting point of individualized treatment through nerve electric feedback, solving the objective calibration problem of initial stimulation intensity, and further realizing real-time dynamic calibration of stimulation parameters in the treatment process through biological impedance feedback, thereby constructing a self-adaptive closed-loop treatment system capable of continuously adapting to the change of physiological states of tissues. In order to achieve the above purpose, the invention adopts the following technical scheme: in a first aspect, the present invention provides an adaptive functional electrical stimulation system based on bimodal feedback, comprising: the main control module is used for executing control logic; The stimulation output module is used for generating and outputting electric stimulation pulses according to the control of the main control module; a nerve electrical signal detection module for detecting a nerve action potential signal induced by the electrical stimulation pulse; the biological impedance testing module is used for measuring the impedance of biological tissues before and after the output of the electric stimulation pulse; The safety isolation module is connected between the stimulation output module and the human body electrode and is used for realizing electric isolation; Wherein, the main control module includes: The safe current determining unit is used for controlling the stimulation output module to output a series of stimulation pulses with increasing amplitude, and determining the corresponding stimulation pulse current amplitude as initial safe current when the nerve action potential is induced for the first time based on the feedbac