Adaptive Duty-Cycle Heated Sensor for Low-Power Accurate Sensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Heated sensing devices, such as thermal conductivity gas sensing devices, face a tradeoff between power consumption and accuracy, with a desire to reduce power levels to extend battery life in portable devices.
Innovation Solution
The implementation of an adaptive duty cycle in sensing devices, where power is applied to the sensing element for both steady-state and non-steady-state time periods, allowing the processor to control power application based on measured responses and adjust between fixed and adaptive duty cycles as needed.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If power is continuously applied to the sensing element to maintain steady state, then measurement accuracy is improved, but power consumption increases
Solution Approach 1:
The patent applies periodic action by implementing a duty cycle approach where power is applied intermittently rather than continuously. The sensing element is powered for a steady-state time period to achieve accurate measurements, then powered down to reduce consumption. This cyclic on-off pattern resolves the contradiction between maintaining measurement accuracy and reducing power consumption.
Solution Approach 2:
The patent implements dynamics by making the duty cycle adaptive rather than fixed. The processor dynamically adjusts the duty cycle parameters (steady-state time period, non-steady-state time period, and number of non-steady-state applications) based on detected changes in the measured response. This allows the system to optimize the balance between accuracy and power consumption in real-time based on environmental conditions.
2Use of energy by moving object
If power is applied for shorter non-steady-state time periods, then power consumption is reduced, but measurement accuracy deteriorates
Solution Approach 1:
The patent applies partial action by using non-steady-state time periods that are intentionally shorter than the full steady-state duration. These partial power applications consume less energy while still providing useful measurement data, especially when combined with multiple sequential applications and averaging. The system accepts that individual partial measurements may be less accurate but compensates through multiple samples.
Solution Approach 2:
The patent implements preliminary action by applying power multiple times for non-steady-state time periods before a full steady-state measurement is taken. These preliminary partial measurements help detect changes early and can trigger or supplement the full steady-state measurement, reducing the overall need for continuous full-power operation.
3Reliability
If the sensing element is heated to operating temperature, then sensing capability is improved, but power consumption increases
Solution Approach 1:
The patent applies periodic action by heating the sensing element intermittently according to the adaptive duty cycle rather than maintaining continuous heating. The element is heated to operating temperature during steady-state time periods when accurate sensing is needed, then allowed to cool during non-steady-state periods to reduce power consumption while maintaining sensing capability when required.
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
This approach reduces power consumption while maintaining desired accuracy and response speed, allowing for substantial power savings without compromising performance.
Implementation Method 1
the sensing element comprises a thermopile and the measured temperature of the sensing element is based on a voltage output of the thermopile
Implementation Method 2
Heated sensing devices, such as thermal conductivity gas sensing devices, require power to raise the sensing element to the desired operating temperature
Data Source
Figure 1
Figure 2
Figure 3A
AI summary
A sensing device is provided. For example, a sensing device may include a sensing element, a power supply, and a processor that controls application of power from the power supply to the sensing element and measures a response of the sensing element. The processor controls the application of power from the power supply to the sensing element according to an adaptive duty cycle in which power is applied to the sensing element repeatedly for a steady-state time period and, for each application of power for a steady-state time period, power is applied to the sensing element two or more times for a non-steady-state time period. The steady-state time period is a time period which is long enough for the sensing element to reach a steady state response. The non-steady-state time period is a time period which is not long enough for the sensing element to reach a steady state response.