MYaccess Research Observation Series
Experiment ID: EXP-021
Study Description
This experimental evaluation focused on validating baseline piezoelectric excitation and measurable signal acquisition using PWM-controlled stimulation under simplified benchtop conditions.
The purpose of this study was not to develop a complete ultrasound imaging platform, but rather to establish foundational electromechanical signal behavior relevant to future wearable ultrasound system development.
The experiment evaluated whether controlled PWM excitation could reproducibly generate detectable signal activity within a simplified TX/RX piezoelectric configuration.
This work represents part of an ongoing iterative engineering and feasibility validation process associated with the MYaccess™ wearable ultrasound research platform.
Research Question
Can a piezoelectric element excited through PWM-controlled stimulation generate measurable and reproducible signal responses detectable through a simplified TX/RX acquisition configuration?
Secondary questions included:
Does the proposed signal pathway demonstrate preliminary feasibility for future wearable ultrasound-oriented architectures?
Does duty cycle influence observable signal behavior?
Can stable baseline signal acquisition be achieved?
Can reproducible waveform activity be detected under controlled conditions?
Objective
To validate whether PWM-controlled excitation can reproducibly generate measurable piezoelectric signal activity within a simplified benchtop TX/RX configuration.
Additional objectives included:
Supporting early-stage engineering risk reduction relevant to wearable ultrasound system development
Evaluating baseline signal acquisition behavior
Observing duty cycle-dependent waveform variation
Establishing repeatable signal detection conditions
Assessing preliminary feasibility of the proposed signal pathway
Materials Used
- PWM signal generator
- DC power source
- Power driver stage
- Piezoelectric transmitting element (TX)
- Piezoelectric receiving/acquisition configuration (RX)
- Portable digital oscilloscope (FNIRSI)
- Mechanical stabilization structures
- Direct coupling and open-air experimental conditions
- Wiring, connectors, and benchtop support platform
Controlled Experimental Setup
A simplified benchtop experimental platform was assembled to evaluate controlled piezoelectric excitation and baseline signal detection.
The transmitting element was stimulated using adjustable PWM excitation parameters while signal behavior was monitored in real time through oscilloscope acquisition.
Mechanical stabilization structures were used to minimize uncontrolled movement and improve repeatability during testing.
The setup was intentionally designed to isolate fundamental signal-generation behavior before progressing toward advanced analog front-end optimization and wearable integration.
The experimental configuration evaluated direct TX/RX interaction under controlled excitation conditions while observing waveform behavior, signal stability, and baseline acquisition characteristics.
Signal Behavior Observations
Under controlled excitation conditions, measurable electrical activity was consistently observed during piezoelectric stimulation.
Observed responses demonstrated:
- Detectable oscillatory signal behavior
- Repeatable waveform acquisition
- Duty cycle-dependent activity variation
- Stable baseline signal acquisition
- Increased oscillatory behavior under higher excitation conditions
Signal amplitude remained measurable within the millivolt range across multiple excitation configurations.
These observations support the ability to generate controlled stimulus-driven signal behavior under simplified benchtop conditions.
Observed waveform responses were directly influenced by excitation parameters, including frequency variation, duty cycle adjustment, and mechanical stabilization of the TX/RX configuration.
Documentation
Three representative images from the experimental platform are included within this report.
In addition, the complete experimental sequence was continuously recorded without interruption and archived as part of the internal MYaccess™ technical development documentation.
The recorded sequence includes waveform acquisition, PWM excitation adjustments, TX/RX interaction behavior, and baseline signal observation under controlled experimental conditions.
Key Preliminary Finding
This experiment demonstrated that controlled PWM excitation can generate measurable and reproducible piezoelectric signal activity within a simplified TX/RX acquisition configuration.
Observed waveform behavior remained detectable across multiple excitation conditions, supporting the feasibility of controlled baseline signal generation and acquisition relevant to future wearable ultrasound-oriented system development.
The experimental observations also suggest that excitation parameters directly influence waveform behavior, signal stability, and oscillatory response characteristics.
Conclusion
This preliminary benchtop experiment demonstrated measurable signal responses during controlled PWM-driven piezoelectric excitation under simplified TX/RX conditions.
The observed waveform activity supports the feasibility of controlled signal generation and baseline acquisition behavior relevant to future wearable ultrasound system development.
These findings establish an early technical foundation for continued iterative engineering development associated with the MYaccess™ research platform.
Future experimental phases may include advanced signal conditioning, analog front-end optimization, tissue-mimicking interface evaluation, and wearable coupling analysis.
Figure captions
Figure 1. Direct baseline PWM-to-piezoelectric excitation configuration used to isolate and evaluate primary signal-generation behavior prior to advanced signal conditioning and system integration.
Figure 2. Intermediate TX/RX acquisition setup demonstrating controlled excitation testing conditions during benchtop waveform evaluation.
Figure 3. Oscilloscope waveform acquisition during PWM-controlled excitation showing measurable oscillatory signal behavior under stabilized experimental conditions.
Documentation note
Images shown here represent selected frames from the experiment.
Additional continuous video documentation of the test is maintained in MYaccess internal records.
