Abstract — COMSOL Nerve Stimulation Model
Comsol Nerve Stimulation Model: Biomedical Engineering, Medical Electronics & Bio-Signal Modeling Integrated Clinical Investigation: Bio-Sensors · Analog Front-Ends (AFE) · Diagnostic Waveforms · DSP Algorithms · ~13781 Words Chapter 1: Electrophysiological Foundations, Action Potentials & Clinical Significance Transcutaneous electrical nerve stimulation is a non-invasive method of treating patients who have indication of pain. This therapy depends on electrical current and pulse duration applied to electrodes of device. To develop the medical device for pain relief, we investigated a numerical model of transcutaneous electrical nerve stimulation and sensory nerve fiber for a forearm with skin structure. The problem we wish to solve is the action potential of sensory nerve fiber based on electric potential of forearm applied electrical stimulation. The model of the sensory nerve fiber is based on the Hodgkin-Huxley model considering temperature-dependent parameters such as conductance, rest potential, opening and closing rates of ions to describe the temperature of human body 37 I. And the model of forearm consists of electrode, stratum corneum, epidermis, dermis, fat, muscle, cortical bone and bone marrow, whose governing equation is Maxwell equation. The electric potential in the model of forearm is coupled with the external current in model of sensory nerve fiber. We use the AC/DC Module and ODE and DAE interfaces in COMSOL Multiphysics ® software and solve the models with varied electric current and pulse duration of electrode in the models. The results showed that the threshold current of sensory nerve fiber increased with pulse duration of electrode in model of forearm, and the rise time of threshold voltage in nerve fiber decrease with electric current of electrodes. We need to study more the model by varying the diameter of sensory nerve fiber, the location and diameter of electrodes.
Sensor Interfacing & Analog Front-End Conditioning
In this keynote talk from COMSOL Day: Biomedical Technologies, Hyun-Joo Park of Abbott Neuromodulation covers how electrical stimulation is used to treat neurological diseases or disorders and discusses the biophysics involved in electrical stimulation. He also discusses how to model and simulate electrical and magnetic stimulation for neuromodulation. Academic publications on related topics, such as axon modeling and spinal cord stimulation systems and modeling, are shared throughout the talk.
Bio-Signal Waveform Analysis & Simulation Findings
Hyun-Joo Park is a staff research scientist at Abbott Neuromodulation, where he focuses on treating chronic pain and movement disorders with neuromodulation. Park holds BS and MS degrees in control and instrumentation engineering from Background: Computational modeling provides an important toolset for designing and analyzing neural stimulation devices to treat neurological disorders and diseases. Modeling enables efficient exploration of large parameter spaces, where preclinical and clinical studies would be infeasible. Current commercial finite element method software packages enable straightforward calculation of the potential distributions, but it is not always clear how to implement boundary conditions to appropriately represent metal stimulating electrodes. By quantifying the effects of different electrode representations on activation thresholds for model axons, we provide recommendations for accurate and efficient modeling of neural stimulating electrodes.
Scope & Clinical Applications
- Real-time multi-parameter vital signs telemetry (ECG, Heart Rate, SpO2, Temperature, Respiration)
- Low-noise Analog Front-End (AFE) conditioning with active Driven Right Leg (DRL) 50 Hz cancellation
- Digital signal processing in MATLAB: Pan-Tompkins QRS detection, FIR/IIR notch, and Continuous Wavelet Transforms
- Finite element tissue bio-electromagnetics and orthopedic mechanical simulations in COMSOL & ANSYS
- Complete Arduino firmware .INO sketches, circuit schematics, and university dissertation reports
Bio-Potential Sensors
ECG, EEG, EMG & PPG optical probes
Low-Noise AFE
INA128 / AD8232 instrumentation amps
Arduino Firmware
Real-time ADC interrupt sampling & BLE
MATLAB Bio-DSP
Pan-Tompkins QRS & wavelet transforms
COMSOL Multiphysics
Tissue electro-thermal & SAR simulation
IEC 60601-1 Safety
Galvanic optical & magnetic isolation
Biomedical Sensors, Electronics & Simulation Suites
Engineered using clinical-grade bio-transducers, low-noise analog amplifiers, and multi-physics simulation platforms.
| Subsystem / Software | Diagnostic & Engineering Role | Instrumentation Tier |
|---|---|---|
| Arduino / ESP32 MCU | High-speed SPI/I2C sensor polling, 500 Hz timer interrupt ADC sampling, BLE telemetry streaming | Embedded Hardware |
| MATLAB R2024b | Pan-Tompkins QRS detection, 50 Hz Butterworth notch filtering, wavelet decomposition, SpO2 ratio | Signal Analytics |
| COMSOL Multiphysics | Electromagnetic tissue absorption (SAR), bio-heat thermal transfer, acoustic transducer wave propagation | Tissue Physics |
| ANSYS Mechanical | Orthopedic bone-implant contact mechanics, prosthetic socket stress distribution, dental load FEA | Biomechanics FEA |
| AD8232 / ADS1298 AFE | Medical-grade 3-lead ECG front-end with built-in instrumentation amp, DRL feedback, and high CMRR | Clinical AFE IC |
Biomedical Acquisition & Multi-Physics Simulation Workflow
Comprehensive signal flow from human bio-potential electrodes and optical sensor probes to embedded Arduino firmware, MATLAB DSP, and COMSOL tissue modeling.
(ECG/EEG/PPG/Temp)
(INA128 / DRL Loop)
500Hz ADC Sampling
& QRS Detection
Tissue FEA Models
& EHR Dashboard
Verified Medical Waveforms, Diagnostic Images & Sensor Circuits
Advantages of the COMSOL Nerve Stimulation Model Project
Why this biomedical engineering project delivers superior academic grades and provides high technical evaluation standing.
Clinical Diagnostic Precision
Combines high-CMRR analog front-ends with precision digital filtering to extract microvolt bio-potentials with high SNR (> 35 dB).
Rigorous IEC 60601-1 Patient Safety
Incorporates dual galvanic isolation barriers (optical/magnetic) ensuring patient auxiliary leakage currents remain strictly under 10 μA.
Multi-Sensor Vital Signs Fusion
Simultaneously captures ECG, PPG, SpO2, Core Temperature, and Respiration for comprehensive physiological health monitoring.
Real-Time Arduino Embedded Firmware
Features optimized C++ interrupt-driven ADC sampling routines ready for immediate deployment on Arduino, ESP32, and STM32.
Validated Pan-Tompkins QRS Algorithm
Executes derivative, squaring, moving-window integration, and dual-threshold peak detection with > 99% R-peak accuracy.
COMSOL & ANSYS Multi-Physics Coupling
Models complex anatomical tissue structures, bio-electromagnetic Specific Absorption Rates (SAR), and prosthetic stress fields.
Driven Right Leg (DRL) Noise Suppression
Actively senses and neutralizes 50/60 Hz powerline hum and common-mode displacement currents without loading patient electrodes.
DICOM Medical Imaging Pipeline
Processes clinical MRI, CT, and Ultrasound scans using MATLAB contrast enhancement and morphological lesion boundary segmentation.
Direct Telehealth & Hospital IoT Readiness
Streams validated vital signs to mobile dashboards and electronic health records over encrypted BLE and MQTT protocols.
Complete Turnkey Project Package
Delivered with full Arduino .INO sketches, circuit schematics, MATLAB .m algorithms, university-format report, and viva defense slides.
Sample Arduino Firmware, ECG Waves & Sensor Telemetry
Representative excerpts illustrating the embedded sensor acquisition loop, live physiological waveform traces, and clinical parameter schedules.
[*] Initializing Analog Front-End (AFE) Signal Acquisition... [✓] Driven Right Leg (DRL) Active Feedback: 50 Hz Hum Attenuated by 42 dB ──────────────────────────────────────────────────────────────────────── [10:14:02.102] TRACE ECG Lead-II: ---__/\_/\_/\___ (Baseline: 0.02 mV | Normal ST Segment) [10:14:02.115] QRS R-Peak Registered (Fiducial Trigger: 1.24 mV | R-R Interval: 832 ms) [10:14:02.128] VITALS Heart Rate: 72.1 BPM | SpO2: 98.5% | PR Interval: 156 ms [10:14:02.140] TRACE ECG Lead-II: ---__/\_/\_/\___ (Baseline Stable | SNR = 36.8 dB) ──────────────────────────────────────────────────────────────────────── [✓] Diagnostic Evaluation: Sinus Rhythm Verified. Zero Ectopic Ventricular Beats.
[*] Synchronizing vital signs telemetry stream across bio-sensor channels...
| Physiological Parameter | Primary Transducer | Measured Amplitude | Sampling Bandwidth | Clinical Status |
|---|---|---|---|---|
| Cardiac Electrocardiogram (ECG) | Ag/AgCl + AD8232 AFE | 1.24 mV (R-Peak) | 0.05 Hz - 150 Hz | NORMAL SINUS |
| Pulse Oximetry (SpO₂) | MAX30102 Dual Red/IR | 98.5% Saturation | 100 Hz Optical | OPTIMAL |
| Heart Rate (HR) | R-R Peak Derivative | 72.1 BPM | 30 - 220 BPM range | EUKINETIC |
| Core Body Temperature | NTC Medical Thermistor | 36.8 °C | 0.1 Hz Thermal | AFEBRILE |
[✓] Diagnostic Evaluation: Patient physiological parameters within verified clinical tolerance band.
Frequently Asked Questions
Project Deliverables & Support
Everything needed from project inception to final viva defense — delivered with expert biomedical support.
.INO Sketches
Schematics
Algorithms
Report
Slides
Models
Datasets
Q&A
Support
Extension