Optical Fibre Queue Detection From Roadway Acoustic Signatures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing traffic sensing technologies, such as inductive loops and radar detectors, struggle to effectively monitor dynamic and extended traffic features like traffic queues due to their limited detection capabilities, often requiring multiple sensors to cover larger areas.
Innovation Solution
Utilizing distributed optical fibre sensing, particularly distributed acoustic sensing, to generate and analyze signals representing acoustic vibrations along roadways, allowing for the detection and estimation of traffic queue boundaries, including front and rear boundaries, by identifying vehicle speed changes and patterns in the acoustic signal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Difficulty of detecting and measuring
If distributed optical fibre sensing is used to detect traffic queues along extended roadways, then the detection capability for extended traffic features is improved, but the device complexity increases
Solution Approach 1:
The optical fibre sensing system divides the extended roadway into multiple detectable segments along its length. Each segment of the fibre independently detects acoustic vibrations from vehicles passing through that location, enabling comprehensive monitoring of traffic queues across the entire roadway stretch without requiring a single complex sensor.
Solution Approach 2:
The optical fibre acts as an intermediary medium that converts acoustic vibrations from vehicles into detectable optical signals. The fibre's acoustic sensitivity allows it to mediate between the mechanical vibrations of passing vehicles and the optical detection system, enabling indirect but effective detection of traffic features.
2Area of stationary object
If multiple sensors are deployed to cover larger roadway areas, then the coverage area increases, but the device complexity and installation requirements increase
Solution Approach 1:
A single optical fibre serves multiple functions simultaneously: it acts as a structural element, a sensing medium for acoustic vibrations, and a data transmission channel. This multi-functionality eliminates the need for separate sensors at multiple locations, as the continuous fibre provides comprehensive monitoring coverage along its entire length.
Solution Approach 2:
The patent merges the functions of multiple distributed sensors into a single continuous optical fibre system. By combining the sensing capabilities along the entire fibre length, the system achieves extended coverage without requiring multiple discrete sensor deployments, thereby reducing overall system complexity.
3Measurement precision
If distributed acoustic sensing is used to detect vehicle speed changes, then the measurement precision for traffic queue boundaries is improved, but the loss of information in noisy acoustic environments increases
Solution Approach 1:
The system uses feedback from multiple acoustic detection points along the fibre to continuously refine queue boundary detection. By monitoring acoustic vibrations at numerous locations and comparing the signals, the system can identify patterns that confirm queue boundaries, thereby maintaining high measurement precision while compensating for noise through collective signal analysis.
Solution Approach 2:
The patent transitions from single-point acoustic detection to distributed spatial detection along the fibre length. This adds a spatial dimension to the detection, allowing the system to distinguish true queue boundary signals from noise by analyzing the spatial distribution and propagation characteristics of acoustic vibrations across multiple fibre segments.
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 detection and monitoring of traffic queues, facilitating improved traffic management through real-time estimation of queue positions and properties, enhancing safety and efficiency by controlling traffic signals and signage.
Implementation Method 1
detecting acoustic vibration using a sensing optical fibre disposed along the roadway
Implementation Method 2
generating a signal representing acoustic vibration along the sensing optical fibre using distributed acoustic sensing
Data Source
AI summary
Methods and apparatus for estimating a position of a boundary of a queue of traffic are disclosed, the queue extending along a roadway. Distributed acoustic sensing is used to generate, as a function of time and of position along the roadway, a signal representing acoustic vibration at a sensing optical fibre that extends along the roadway. A queue signature is detected in the signal of either the slowing down of a plurality of vehicles as they approach the boundary of the queue, or speeding up of a plurality of vehicles as they advance from the departed boundary of the queue. A position of the boundary of the queue is then estimated from the detected queue signature. Methods and apparatus are also disclosed for controlling one or more road traffic signals by using distributed acoustic sensing to detect acoustic vibration at one or more sensing optical fibres disposed along a roadway, as a function of time and of position along a roadway, and controlling the one or more road traffic signals responsive to the detected acoustic vibration.