Proximity Sensor Gap Measurement Without Aircraft Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Proximity sensors in pressurized access doors are difficult to mechanically test due to limited space constraints, leading to potential false indications and unnecessary flight delays, as existing solutions like mechanical gauges and electronic rigging aids face challenges with accuracy and power availability.
Innovation Solution
A portable, hand-held, self-powered proximity sensor interface device (PSID) that uses a frequency generator and RC circuit to electronically measure the air gap between proximity sensors and their targets, operating in Gap Measurement and Go/No-Go modes, allowing for accurate gap assessment without requiring aircraft power.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If mechanical gauges (feeler gauges) are used to measure the air gap, then mechanical placement can be verified, but the limited space constraints make it virtually impossible to insert hard feeler gauges into the space to successfully measure the gap
Solution Approach 1:
The patent replaces mechanical feeler gauges with an electronic measurement system consisting of a proximity sensor, frequency generator, and RC circuit. The electronic system measures the air gap through electrical signal timing rather than mechanical insertion, eliminating the space accessibility problem while maintaining measurement precision.
Solution Approach 2:
The patent introduces an intermediary electronic measurement device that can access the measurement space without physical contact. The proximity sensor and RC circuit act as intermediaries to measure the air gap indirectly through electrical fields and signal timing, avoiding the need to physically insert tools into the confined space.
2Measurement precision
If electronic rigging aids are used to measure the air gap, then accurate electronic measurement can be achieved, but these devices require aircraft power which may not be available at pre-integration sites
Solution Approach 1:
The patent makes the measurement device self-powered by incorporating a frequency generator and RC circuit within the device itself. The device generates its own test signals and measures the air gap using its internal power source, eliminating dependence on external aircraft power systems and enabling operation at pre-integration sites.
Solution Approach 2:
The patent segments the measurement system into self-contained functional modules (frequency generator, proximity sensor, RC circuit, processor) that operate independently with internal power. This segmentation allows the device to function without external power infrastructure, resolving the power availability contradiction.
3Ease of operation
If modified bent-up gauges are used for measurement, then some form of mechanical rigging can be attempted, but these gauges are not accurate and difficult to insert into the air gap
Solution Approach 1:
The patent replaces the inadequate mechanical bent-up gauges with an electronic measurement system that achieves both easy insertion (through non-contact sensing) and high measurement accuracy (through precise electrical signal timing and processing).
4Ease of manufacture
If clay or metrological rubber is used to model the air gap, then some measurement can be captured, but capturing the true air gap in a modeling medium is not very accurate
Solution Approach 1:
The patent replaces physical modeling methods (clay, metrological rubber) with an electronic measurement system that directly measures the air gap through electrical fields and signal timing, eliminating the inaccuracies inherent in physical modeling while maintaining ease of implementation.
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 PSID provides accurate and reliable gap measurements, reducing the need for mechanical rigging and ensuring proper sensor placement, thereby preventing false indications and enhancing the efficiency of aircraft door installation processes.
Implementation Method 1
a frequency generator, a processing device, a memory associated with the processing device, a display, and an RC circuit. The processing device is programmed to route a signal generated by the frequency generator through the proximity sensor and the RC circuit for a prescribed period of time.
Implementation Method 2
The processing device is further programmed to cause the display to provide an indication of whether the relative position of the proximity sensor and the target device are within prescribed tolerances, based on the discharge time.
Data Source
AI summary
A proximity sensor interface device (PSID) for determining if a proximity sensor is in an acceptable position with respect to a target device is described. The PSID includes a frequency generator, a processing device, a memory associated with the processing device, a display, and an RC circuit. The processing device is programmed to route a signal generated by the frequency generator through the proximity sensor and the RC circuit for a prescribed period of time and the processing device is programmed to measure a discharge time of the RC circuit. The processing device is further programmed to cause the display to provide an indication of whether the relative position of the proximity sensor and the target device are within prescribed tolerances, based on the discharge time.