Passive Infrared Sensor Network for Occupancy Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for monitoring the occupancy of spaces, such as office areas or conference rooms, face challenges including high infrastructure costs, privacy concerns, and limited resolution of data provided by traditional sensors like cameras and passive IR sensors.
Innovation Solution
A system utilizing a network of battery-operated passive infra-red motion sensors with overlapping footprints, coupled with a central server for data analysis, to monitor the state of occupancy in a facility. The sensors record movement events with timestamps and send logs to the server for synchronization and analysis, providing enhanced spatial and temporal resolution without compromising anonymity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If cameras are used for monitoring occupancy, then measurement precision is improved, but device complexity and cost increase due to power and data cables infrastructure
Solution Approach 1:
The patent replaces active camera-based monitoring systems with passive infrared sensors that detect thermal radiation from occupants. This substitution eliminates the need for complex power and data cable infrastructure while maintaining occupancy detection capability through thermal energy detection rather than optical imaging.
Solution Approach 2:
The system changes the detection parameter from optical imaging (cameras) to thermal radiation detection (infrared sensors). This parameter change allows for simplified infrastructure since passive IR sensors require minimal power and can transmit data through simpler wireless or low-power wired connections, resolving the infrastructure complexity issue.
2Measurement precision
If cameras are used for monitoring occupancy, then measurement precision is improved, but loss of information increases due to privacy concerns requiring identification
Solution Approach 1:
The patent substitutes camera-based visual identification systems with passive infrared thermal detection. This replacement inherently protects privacy by detecting only thermal signatures rather than visual images, thus preventing identification of individuals while still accurately monitoring occupancy status.
3Use of energy by moving object
If passive IR sensors are used for monitoring occupancy, then use of energy is reduced, but measurement precision deteriorates providing only 1 pixel of information
Solution Approach 1:
The patent divides the monitoring area into multiple overlapping zones, each monitored by a separate passive IR sensor. By segmenting the space and using multiple sensors with overlapping footprints, the system reconstructs detailed occupancy information from multiple 1-pixel measurements, effectively achieving high-resolution monitoring while maintaining low power consumption of individual sensors.
Solution Approach 2:
The system transitions from single-sensor spatial monitoring to multi-sensor temporal-spatial monitoring. By deploying multiple passive IR sensors that detect occupancy from different zones and combining their data over time, the system achieves high-resolution occupancy mapping without requiring each sensor to consume high power.
4Measurement precision
If multiple presence sensors are placed throughout a facility, then measurement precision is improved, but device complexity and cost increase
Solution Approach 1:
The patent merges data from multiple passive IR sensors with overlapping zones into a unified occupancy model. By combining the detection zones of multiple low-cost sensors and processing their combined output centrally, the system achieves facility-wide high-resolution occupancy monitoring without the complexity and cost of deploying expensive individual sensor systems throughout the facility.
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 system effectively monitors the occupancy of large facilities with high accuracy and low power consumption, allowing for efficient use of space and reducing costs associated with infrastructure and privacy concerns.
Implementation Method 1
battery-operated passive infra-red motion sensors
Data Source
Figure 1a~1b
Figure 2~3
Figure 4~5
AI summary
The present invention relates to the management of shared work spaces. A goal is to accurately reflect the actual status of a booking as close to real time as possible. Embodiments of the invention allow for low-power, battery operated, motion sensor devices to report the actual status of shared work spaces to a centralised server using existing wireless communications means in the environment where the shared work spaces are to be managed.