Radar and Optical Sensor Fusion for Vehicle Tracking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radar systems for monitoring vehicles on roads face limitations such as false detections due to multiple bounces, low angular resolution, and difficulty in tracking stationary vehicles, leading to inefficiencies and missed violations.
Innovation Solution
A system combining a radar sensor with a time-of-flight optical sensor or optical image sensor for improved vehicle tracking, where radar and optical data are synchronized and compared to eliminate false positives and enhance tracking accuracy, particularly for stationary vehicles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If radar sensor is used for vehicle monitoring, then detection range and speed measurement precision are improved, but false detections increase due to multiple bounces
Solution Approach 1:
The patent combines radar sensor data with optical sensor data (camera or LIDAR) to create a fused detection system. The optical sensor provides visual confirmation of detected objects, allowing the system to distinguish between real vehicles and false detections caused by multiple bounces. This merging of complementary sensor modalities resolves the contradiction by maintaining radar's precise speed measurement capability while using optical data to filter false positives.
Solution Approach 2:
The optical sensor acts as an intermediary that validates radar detections. When the radar detects a potential target, the optical sensor captures imagery or range data of the same spatial location to confirm whether a actual vehicle is present. This intermediary verification process eliminates false detections while preserving the radar's accurate speed measurements.
2Area of stationary object
If radar sensor operates in wide detection range, then coverage area is improved, but angular resolution deteriorates
Solution Approach 1:
The patent merges radar's wide-area coverage capability with optical sensor's high angular resolution. The radar sensor provides broad detection coverage and initial target acquisition, while the optical sensor delivers precise angular positioning and vehicle identification. This combination allows the system to maintain wide detection range while achieving high angular resolution through the optical component.
Solution Approach 2:
The system transitions from relying solely on radar's angular measurements to incorporating optical imagery or LIDAR data that provides precise spatial positioning in two or three dimensions. This dimensional enhancement allows accurate angular resolution to be achieved alongside wide coverage by using the optical sensor's superior spatial discrimination capabilities.
3Speed
If radar tracking is used for moving vehicles, then speed detection is improved, but tracking of stationary vehicles deteriorates
Solution Approach 1:
The patent combines radar's speed detection excellence with optical sensor's ability to detect stationary objects. The radar continues to provide accurate speed measurements for moving vehicles, while the optical sensor independently detects and tracks stationary vehicles that produce no Doppler signal. This merging allows the system to maintain superior speed detection while adding reliable stationary vehicle tracking capability.
Solution Approach 2:
The optical sensor provides multi-functionality by serving both as a validator for radar detections of moving vehicles and as a primary detector for stationary vehicles. This universal detection capability ensures that both moving and stationary vehicles are reliably tracked, with the optical sensor compensating for radar's inability to detect stationary targets.
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 combination improves detection reliability by reducing false positives and enabling more precise monitoring of vehicle speed and position, including stationary vehicles, while maintaining the precision of radar speed measurements.
Implementation Method 1
A radar uses the principle of the Doppler effect to measure speed. It emits a sustained (or continuous) wave into a radar detection range which is reflected by any object located in the radar detection range. Due to the Doppler effect, this reflected wave has a slightly different frequency to that emitted
Implementation Method 2
A position measurement is provided by the measurement of the time of flight of the wave, which makes it possible to obtain the distance between the radar and the target vehicle which reflected the wave
Implementation Method 3
the second remote sensor being an optical sensor, in particular a time-of-flight optical sensor or an optical image sensor
Data Source
AI summary
The invention relates to a process for monitoring vehicles on a road by a system comprising at least one radar sensor and a second sensor different from the radar sensor, wherein the second remote sensor is a time-of-flight optical sensor or optical image sensor, the process comprising a temporal readjustment and a spatial matching in order to obtain a set of measurement points each assigned to first characteristics derived from the radar data and second characteristics derived from the optical data, the determination of the radar vehicle trackings and of the optical vehicle trackings, a comparison of similarity between the radar vehicle trackings and the optical vehicle trackings, the elimination of the radar vehicle trackings for which no optical vehicle tracking is similar, the process comprising monitoring a parameter derived from first characteristics of a retained radar vehicle tracking.