Infrared Object Detection Using Reflection Change Thresholds
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Active infrared sensors face limitations in object detection due to the dependence of reflection magnitude on both distance and object surface reflectivity, leading to inaccurate or missed detections when only reflectivity is considered.
Innovation Solution
A system that uses a computer to receive and analyze reflection magnitude changes from active infrared sensors, determining object presence by comparing these changes to a threshold, independent of object material, and adjusts movement of platforms like vehicle seats based on distance and object location.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If active infrared sensor uses only reflection magnitude for object detection, then the detection process is simple, but the detection accuracy deteriorates due to dependence on object surface reflectivity
Solution Approach 1:
The patent changes the detection parameter from absolute reflection magnitude to change in reflection magnitude (ΔIR). By detecting the change in infrared light reflection rather than the absolute value, the system eliminates dependence on object surface reflectivity properties, thereby improving detection accuracy across different materials while maintaining simple processing logic.
2Ease of operation
If active infrared sensor detects only magnitude of reflected infrared light, then the sensor operation is simple, but detection reliability deteriorates when object material varies
Solution Approach 1:
The system transitions from using absolute reflection magnitude to using the change in reflection magnitude (ΔIR) as the detection parameter. This parameter change makes the detection reliable across different object materials (fabric, leather, metal, etc.) while keeping the sensor operation simple, as the computer only needs to compare ΔIR values against a threshold.
3Length of stationary object
If active infrared sensor uses reflection magnitude independent of distance, then the detection range is extended, but the detection accuracy deteriorates due to distance-dependent reflection variations
Solution Approach 1:
The system performs preliminary action by moving the platform (e.g., vehicle seat) before or during object detection. By intentionally creating a known distance change, the system generates a measurable change in reflection magnitude that is independent of the absolute distance to the object. This allows accurate detection across extended ranges while compensating for distance-dependent attenuation.
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
Improves the accuracy of object detection by focusing on changes in reflection magnitude with respect to distance, enabling effective detection and movement control of platforms to avoid obstacles, enhancing safety and operational efficiency in environments like vehicles.
Implementation Method 1
An active infrared sensor transmits infrared light to the field of view of the sensor and can detect reflections of the transmitted infrared light from an object within the sensor field of view
Implementation Method 2
An infrared sensor can detect a magnitude of infrared light received from a sensor field of view
Data Source
AI summary
A system includes a computer including a processor and a memory. The memory stores instructions executable by the processor to receive a reflection magnitude from an infrared sensor during a movement of an object relative to the infrared sensor, to determine a change of the reflection magnitude, and to detect the object based on comparing the determined change of the received reflection magnitude to a change threshold.