Active Pulse Sensor Vibration for Low Perfusion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pulse oximetry and blood parameter monitoring systems face challenges in obtaining valid measurements when there is low blood perfusion, resulting in weak sensor signals.
Innovation Solution
A disposable active pulse sensor is designed with an emitter, detector, and an unbalanced electric motor that induces pulsatile blood flow by vibrating, allowing for the transmission of optical radiation and generation of a sensor signal even in low perfusion conditions, ensuring sufficient blood flow for accurate measurements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If passive pulse oximetry is used, then device complexity is reduced, but measurement reliability deteriorates in low perfusion conditions
Solution Approach 1:
The patent applies mechanical vibration through an electric motor that vibrates at a frequency matching the heart rate, mechanically inducing pulsatile blood flow in the tissue site. This vibration-based approach strengthens the sensor signal by creating artificial pulsations that enhance optical detection, thereby improving measurement reliability in low perfusion conditions without requiring complex active control systems.
Solution Approach 2:
The system uses the patient's own heart rate to drive the vibration frequency of the electric motor, creating a self-regulating mechanism. The motor vibrates at the detected heart rate frequency, automatically adapting to the patient's physiological state. This self-service approach improves reliability by synchronizing with natural physiology while avoiding the need for external control systems.
2Measurement precision
If active pulse induction is applied, then sensor signal strength is improved, but device complexity increases
Solution Approach 1:
The patent employs mechanical vibration through a simple electric motor that generates oscillations at the heart rate frequency. This mechanical approach directly strengthens the sensor signal by creating pulsatile blood flow, improving measurement precision while maintaining relatively simple device architecture through the use of conventional vibration mechanisms.
Solution Approach 2:
The system implements periodic action by vibrating the tissue site at repeated cycles matching the heart rate frequency. This periodic mechanical stimulation creates consistent pulsatile blood flow patterns that enhance optical detection. The periodic nature of the vibration allows for predictable and reliable signal generation without requiring complex variable control systems.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The active pulse sensor effectively enhances sensor signal strength, enabling reliable measurements of blood constituents by artificially inducing pulsatile blood flow, thereby overcoming the limitations of low perfusion scenarios.
Implementation Method 1
an unbalanced electrical motor that vibrates when energized... vibration from the unbalanced electrical motor induces pulsatile blood flow within the tissue site
Implementation Method 2
the emitter transmits the optical radiation into the tissue site and the detector generates a sensor signal responsive to the intensity of the optical radiation after attenuation by the pulsatile blood flow
Data Source
AI summary
A disposable active pulse sensor has an emitter that generates optical radiation having a plurality of wavelengths, a detector that is responsive to the optical radiation and an unbalanced electrical motor that vibrates when energized. A tape assembly removably attaches the emitter, the detector and the unbalanced electrical motor to a tissue site. The tape assembly also physically mounts the emitter, the detector and the unbalanced electrical motor in a spatial arrangement so that vibration from the unbalanced electrical motor induces pulsatile blood flow within the tissue site, the emitter transmits the optical radiation into the tissue site and the detector generates a sensor signal responsive to the intensity of the optical radiation after attenuation by the pulsatile blood flow within the tissue site.