AC Coupled Skin Temperature Control System

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing transcutaneous CO2 monitoring systems face challenges in accurately controlling skin temperature for reliable arterialization, with risks of skin burns and potential electronic failures leading to uncontrollable heater currents, necessitating improved miniaturized and safe temperature control solutions.

Innovation Solution

A system comprising a temperature sensor module, microcontroller module generating AC heating pulse signals through sequential code steps, a coupling module transforming these signals to eliminate DC components, and a heating module producing controlled heat pulses, ensuring safe and precise temperature control with reduced risk of software hang-ups.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If DC coupled heating is used to maintain skin temperature for arterialization, then heating effectiveness is improved, but risk of uncontrollable heater currents and skin burns increases

Engineering Contradiction:
Improveskin temperatureVSAvoidheater current control
Core Design Contradiction:
TemperatureVSReliability

Solution Approach 1:

The patent applies periodic AC heating pulses instead of continuous DC heating. The heater is controlled to deliver periodic heating pulses with duty cycles between 1% and 100%, creating an AC-coupled system that periodically heats the skin to maintain arterialization while inherently limiting maximum current exposure and eliminating the risk of runaway DC currents.

Inventive Principle:
Principle #19Periodic action

2Reliability

If hardware safety circuits are added to prevent uncontrollable heater currents, then safety is improved, but device complexity increases

Engineering Contradiction:
Improveheater current controlVSAvoidhardware safety circuits
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces complex hardware safety circuits with a software-based control approach. A microcontroller executes safety-checking code that monitors heater current and temperature, eliminating the need for substantial additional hardware safety circuits while maintaining reliable protection against uncontrollable heating.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Volume of moving object

If miniaturized controller design is implemented, then device portability is improved, but thermal management precision may deteriorate

Engineering Contradiction:
Improvecontroller sizeVSAvoidtemperature control precision
Core Design Contradiction:
Volume of moving objectVSManufacturing precision

Solution Approach 1:

The periodic AC pulse heating approach enables miniaturization while maintaining precision by using short, controlled heating bursts followed by measurement intervals. This pulsed operation reduces average power consumption and heat accumulation, allowing smaller thermal masses and compact design without sacrificing temperature control accuracy.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The system uses feedback control where the microcontroller continuously monitors skin temperature and adjusts the heating pulse duty cycle accordingly. This closed-loop control maintains precise temperature regulation even in the miniaturized design, compensating for reduced thermal mass and faster temperature dynamics.

Inventive Principle:
Principle #23Feedback

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 system provides enhanced safety and precision in skin temperature control, minimizing the risk of skin burns and electronic failures, while allowing for miniaturization and adaptability to various healthcare applications beyond transcutaneous sensing.

Implementation Method 1

a heating module, which is coupled to the coupling module and which is configured to generate heat according to the transformed AC heating pulse signals

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 2

a temperature sensor module, which is configured to measure a skin temperature value

Methodology Applied
Scientific EffectThermal sensing:

Data Source

PatentEP3212136B1System and method for controlling a temperature
Publication Date: 2020.10.07 KONINKLIJKE PHILIPS NV
  • EP3212136B1 patent drawingFigure 1
  • EP3212136B1 patent drawingFigure 2
  • EP3212136B1 patent drawingFigure 3

AI summary

The present invention relates to a system (100) for controlling a temperature, the system (100) comprising: a temperature sensor module (10), which is configured to measure a temperature value; a microcontroller module (20), which is coupled to the temperature sensor module (10) and which is configured to generate AC heating pulse signals by separate sequential code steps based on the measured temperature value; a coupling module (30) which is coupled to the microcontroller module (20) and which is configured to transform the generated AC heating pulse signals into transformed AC heating pulse signals using a transfer function which is substantially zero for DC signal components; and a heating module (40) which is coupled to the coupling module (30) and which is configured to generate heat according to the transformed AC heating pulse signals.