Through-Article Optical Sensing for Movement-Resilient Vital Signs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solutions for measuring heart rate and respiratory rate require sensors to be placed directly on the skin, which can be uncomfortable for extended wear and prone to errors due to movement, leading to inaccurate or unmeasurable readings.
Innovation Solution
A sensor system is placed outside an article, such as a diaper, that pulses light through the article to measure light returned from the skin, using optical methods and inertial sensors to determine heart and respiratory rates, and compensates for movement and thickness changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a sensor is placed directly on the skin to measure heart rate and respiratory rate, then measurement precision is improved, but comfort and ease of operation deteriorate due to extended wear discomfort
Solution Approach 1:
The patent introduces an intermediary article (such as a diaper or clothing item) that contains the optical transmitter and sensor. This intermediary allows the sensor system to measure physiological parameters without direct skin contact, combining the benefits of accurate measurement with comfort during extended wear. The article acts as a mediator between the measurement system and the infant's skin.
2Measurement precision
If a sensor is placed directly on the skin to obtain measurements, then measurement capability is improved, but reliability deteriorates when the wearer is moving due to sensor misalignment
Solution Approach 1:
The patent employs dynamic compensation mechanisms that adapt to movement in real-time. The system uses motion detection sensors (accelerometers, gyroscopes) to detect movement and dynamically adjusts the optical measurement parameters or compensates for the movement effects. This allows reliable measurements to be obtained even when the infant is moving, as the system continuously adapts to the changing conditions.
Solution Approach 2:
The system incorporates feedback from motion detection sensors to monitor and compensate for movement effects on the optical measurements. By continuously monitoring movement and adjusting the measurement process accordingly, the system maintains measurement reliability during activity. The feedback loop allows the system to distinguish between signal changes caused by physiology versus those caused by movement.
3Reliability
If existing optical sensing solutions are used with movement compensation, then reliability during movement is improved, but device complexity increases due to multiple sensors and processing requirements
Solution Approach 1:
The patent combines multiple sensing functions (optical measurement, motion detection, temperature sensing) into a single integrated article. Rather than using separate devices for each function, the system merges these capabilities into one unified platform, reducing overall system complexity while maintaining the benefits of movement compensation and accurate physiological measurement.
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
Enables accurate and continuous measurement of heart and respiratory rates without direct skin contact, minimizing discomfort and improving measurement reliability by adjusting to wearer movement and diaper thickness changes.
Implementation Method 1
causes a light source to transmit a pulse of light through an article to an area of skin and determines a measurement of light returned from the article
Data Source
Figure 1
Figure 2
Figure 3~3B
AI summary
Various examples are described for detecting heart rate and respiratory rate by using measurements of light applied to skin through an article. For example, a sensor application obtains a set of measurements of light. The application compensates for a contribution of the article based on one or more known optical properties of the article. The sensor application further determines, from the set of measurements of light, a periodic change in amplitude. The sensor application identifies the periodic change in amplitude as a heart rate having an identical periodicity. The sensor application identifies a respiratory rate as equal to the rate of change of the heart rate.