Acoustic Pulse Envelope Analysis for Stationary Object Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for detecting changes in transportation systems, such as elevator cars, are inadequate in detecting stationary objects and people, and are not suitable for environments with transparent walls or floors, and often require movement to function effectively.
Innovation Solution
A method using a sound sensor and evaluation unit that emits an acoustic pulse, records the response signal, determines the envelope, and analyzes the spectrum to detect changes, allowing for reliable detection of stationary objects and people, independent of the pulse frequency, and compares actual measurements to reference measurements to determine changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If Doppler-based ultrasound sensors are used for person detection, then movement detection capability is improved, but stationary objects and people cannot be detected
Solution Approach 1:
The patent changes the detection parameter from Doppler frequency shift (motion-based) to acoustic echo time-of-flight and amplitude characteristics (position-based). By measuring the time for acoustic pulses to travel to and from objects, and analyzing the amplitude of returned echoes, the system can detect both stationary and moving objects equally effectively.
2Loss of information
If optical sensors are used for change detection, then visual information is obtained, but the system fails in environments with transparent walls or floors
Solution Approach 1:
The patent replaces optical detection systems with acoustic detection systems. Acoustic waves interact with all materials differently than light - they reflect off transparent materials and can detect objects behind transparent barriers. This substitution makes the detection system universally applicable regardless of wall or floor transparency.
3Measurement precision
If optical image analysis is used for change detection, then visual changes are detected, but moving content on screens causes inaccurate detection
Solution Approach 1:
The patent replaces optical image analysis with acoustic echo analysis. Acoustic waves reflect off physical objects and surfaces, and the returned echo patterns provide information about object presence and movement. This acoustic approach is immune to interference from visual displays or screen content, as sound waves interact with the physical environment rather than visual information.
4Reliability
If acoustic pulse emission is used for detection, then detection capability is improved, but the system must distinguish between frequency variations and actual changes
Solution Approach 1:
The patent extracts and analyzes only the envelope of the acoustic signal, which contains the amplitude modulation information related to object presence and movement. By focusing on the envelope rather than the entire frequency spectrum, the system simplifies the analysis while retaining the essential detection information, eliminating the need to distinguish between frequency variations and actual object changes.
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 method enables robust and reliable detection of changes in transportation systems, including elevator cars, by accurately identifying the presence or absence of people and objects, and is effective in environments with transparent components, improving safety and operational efficiency.
Implementation Method 1
Emitting an acoustic pulse into the area to be monitored, recording an acoustic response signal of the pulse as the actual signal
Implementation Method 2
determining an envelope of the actual signal, detecting changes based on the envelope
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Disclosed is a method for detecting changes in an area to be monitored of a conveying system. For this purpose, said conveying system has a sound sensor and an evaluation unit connected to the sound sensor. The method is characterized by emitting an acoustic pulse (62) into the area to be monitored, recording an acoustic response signal of the pulse (62) as an actual signal (64), determining an envelope (66) of the actual signal (64), detecting changes on the basis of the envelope (66).