Capacitive Patient Monitoring Bed with Electrode Matrix
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Capacitive sensing for cardio pulmonary monitoring is prone to variations due to patient motion, sweat, contact intimacy, and distance, and is vulnerable to parasitic signals, making it unreliable for home use without direct skin contact.
Innovation Solution
A capacitive patient monitoring system with a matrix of electrodes integrated into a bed, allowing for individual electrode selection based on capacitance measurements, using a dielectric material that changes capacitance with patient position, and optionally using the patient's body as a counter electrode, with shielding to filter out parasitic signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If capacitive sensing is used for non-contact monitoring, then the system becomes unobtrusive and suitable for home use, but the measurement reliability deteriorates due to variations from patient motion, sweat, and parasitic signals
Solution Approach 1:
The system divides the monitoring function into multiple independent electrodes arranged in a matrix, where each electrode can be individually selected and evaluated. This segmentation allows the system to identify and use only the most reliable electrodes for measurement, rather than relying on a single contact point that is vulnerable to motion and sweat interference.
Solution Approach 2:
The bed sheet with integrated electrodes serves multiple functions: it provides a comfortable sleeping surface while simultaneously enabling capacitive sensing for cardio-pulmonary monitoring. The electrodes can detect various physiological parameters including respiration rate, heart rate, and ECG signals, making the system versatile for different monitoring needs.
2Device complexity
If a single electrode or small number of electrodes is used, then the system complexity is reduced, but the ability to accommodate arbitrary patient positions deteriorates
Solution Approach 1:
The system transitions from using a single electrode or small array to a two-dimensional matrix of electrodes distributed across the bed surface. This dimensional expansion allows the system to cover a larger area and detect signals from patients in various positions, effectively adding spatial redundancy to overcome position-dependent signal variability.
Solution Approach 2:
The system performs preliminary evaluation of electrode capacitance values before actual monitoring begins. By pre-identifying electrodes with optimal coupling to the patient's body based on their capacitance characteristics, the system prepares the best possible measurement configuration in advance, ensuring reliable signals regardless of patient position.
3Adaptability or versatility
If more electrodes are used in a matrix arrangement, then patient position adaptability improves, but the device complexity and electrode selection requirements increase
Solution Approach 1:
The system automatically evaluates and selects the most suitable electrodes based on their capacitance values without requiring manual intervention. The control unit autonomously processes the capacitance measurements from all electrodes in the matrix, identifies those with optimal coupling to the patient, and configures the monitoring signal accordingly, eliminating the need for complex manual electrode selection procedures.
Solution Approach 2:
The system uses real-time capacitance measurements as feedback to dynamically select and adjust which electrodes are used for monitoring. By continuously evaluating the coupling quality through capacitance sensing and adjusting the electrode selection based on this feedback, the system maintains optimal measurement conditions even as patient position changes during sleep.
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 reliable, non-contact cardio pulmonary monitoring that is unobtrusive and suitable for home use, with improved signal quality and reduced interference, allowing for accurate detection of bio-signals like ECG and bio-impedance measurements.
Implementation Method 1
capacitive sensing of bio signals inherently relies on the capacitive coupling of the 'body electrode' to the sensing capacitance
Implementation Method 2
capacitive coupling of the 'body electrode' to the sensing capacitance
Data Source
AI summary
The present invention relates to a patient monitoring system for monitoring cardio pulmonary performance or the like by means of capacitive measurement. Further the invention relates to a method for monitoring cardio pulmonary performance or the like by means of a capacitive measurement. In order to provide a reliable technique for monitoring cardio pulmonary performance or the like, which technique is particularly suitable for home use, a patient monitoring system (1) for monitoring cardio pulmonary performance or the like by means of capacitive measurement is suggested, said system (1) comprising a number of electrodes (2) arranged in the form of a matrix (3), said electrodes (2) being adapted to be integrated with a bed (4) or the like, each electrode (2) being individually selectable, means (5) for determining a number of electrodes (2) depending on the position of the patient on the bed (4) or the like, said means (5) being adapted to determine the number of electrodes (2) by determining the capacitance of a number of electrodes (2), and means (5) for selecting a number of said determined electrodes (2) for carrying out a capacitive measurement.