Non-Contact Biometric Sensing via Laser Doppler Vibrometry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
First responders face challenges in assessing victims' vital signs during emergency responses due to protective equipment and hazardous conditions that prevent contact, and existing non-contact solutions are inadequate for standoff measurements.
Innovation Solution
A non-contact biometric sensing device combining laser Doppler vibrometry and infrared imaging, which measures mechanical motion and temperature distribution from a safe distance, allowing for the assessment of vital signs such as pulse rate and breathing rate without physical contact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If contact-based triage methods are used to measure vital signs, then measurement accuracy is improved, but responder safety deteriorates due to protective equipment and hazardous conditions
Solution Approach 1:
The patent replaces mechanical contact-based measurement systems with optical sensing systems. Laser Doppler vibrometry and infrared imaging capture physiological signals (pulse, respiration, temperature) through non-contact optical fields, eliminating the need for physical contact while maintaining measurement capability. This substitution resolves the contradiction by preserving measurement accuracy through advanced optical detection while removing the safety risk associated with contact in hazardous environments.
Solution Approach 2:
The patent introduces optical fields (laser beams and infrared radiation) as intermediaries between the responder and the victim. These electromagnetic fields serve as mediators that can penetrate or bypass protective equipment barriers, carrying physiological information from the victim to the sensing device without requiring direct physical contact. This intermediary approach maintains measurement precision while ensuring responder safety by keeping the responder at a safe distance.
2Object-affected harmful factors
If non-contact sensing methods are used to ensure responder safety, then responder safety is improved, but measurement precision deteriorates due to inability to detect subtle physiological signals
Solution Approach 1:
The patent employs laser Doppler vibrometry to detect minute mechanical vibrations of the victim's body surface caused by physiological activities such as pulse waves and respiration. The laser beam interacts with these subtle vibrations, and the Doppler shift in the reflected light frequency provides precise measurement of the vibrations. This approach maintains measurement precision by detecting extremely small mechanical movements from a distance, resolving the contradiction between non-contact safety and accurate detection.
Solution Approach 2:
The patent utilizes infrared imaging to detect changes in thermal parameters of the victim's body. By measuring temperature distribution and thermal radiation patterns, the system can infer physiological states such as blood flow changes, respiration rate, and overall metabolic status. This parameter-based approach (using thermal parameters instead of direct mechanical contact) enables accurate vital signs detection while maintaining responder safety through non-contact measurement.
3Object-affected harmful factors
If protective equipment is worn to protect responders, then responder safety is improved, but ease of operation deteriorates due to inability to physically examine victims
Solution Approach 1:
The patent replaces manual mechanical examination procedures with automated optical sensing systems. The laser Doppler vibrometer and infrared camera automatically capture and process physiological signals without requiring the responder to physically touch or closely approach the victim. This substitution maintains ease of operation by providing automated measurement capabilities that work effectively through protective equipment, resolving the contradiction between protection and operational effectiveness.
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
Enables accurate and safe assessment of victims' physiological parameters from a standoff distance, minimizing risk to first responders and overcoming limitations of existing contact-based triage methods.
Implementation Method 1
measuring mechanical motion with a laser
Implementation Method 2
measuring temperature distribution with an infrared camera
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A non-contact biometric sensing device is described. The device includes a processing device, a user interface communicatively coupled to the processing device, a display communicatively coupled to the processing device, a laser doppler vibrometer sensor communicatively coupled to the processing device, and an infrared camera communicatively coupled to the processing device. The processing device is programmed to utilize mechanical motion data received from the laser doppler vibrometer sensor and thermal distributions data from the infrared camera to calculate biometric data, when signals originating from the laser doppler vibrometer sensor and the infrared camera are reflected back towards the device from a target.