Laser Scanner Road Alignment via Reflection Signals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for aligning the scan plane of a laser scanner with a roadway surface are error-prone and require known transmitter height or additional aids, limiting their automation and applicability.
Innovation Solution
An automatic method that aligns the laser scanner's scan plane parallel to the road surface by eliminating unknown inclination angles and determining height through reflection signal measurements, using a motorized tilting unit to adjust the scanner axes based on measured data, without requiring additional aids or known transmitter height.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Extent of automation
If manual alignment using an inclinometer is used, then alignment can be performed without additional aids, but the process is error-prone and cannot be automated
Solution Approach 1:
The patent replaces the manual mechanical inclinometer alignment process with an automated optical measurement system. The laser scanner automatically measures reflection signals from the road surface to determine inclination angles, substituting mechanical manual alignment with an optical-electronic automated system that eliminates human error while maintaining alignment capability without additional physical aids.
Solution Approach 2:
The laser scanner performs self-alignment by automatically measuring the road surface geometry through its own reflection signals. The system uses its measurement capability to determine the inclination angles and automatically adjusts its scan plane orientation, making the alignment process self-service without requiring external inclinometers or additional alignment aids.
2Extent of automation
If automatic alignment using two well-defined bodies is used, then alignment can be automated, but the height of the transmitter must be known and special aids are required
Solution Approach 1:
The patent extracts the alignment function from the laser scanner's physical setup requirements. Instead of needing known transmitter height or special alignment bodies, the system extracts only the necessary measurement data from the road surface reflection signals and computationally determines the inclination angles, eliminating the need for additional physical aids or pre-known parameters.
Solution Approach 2:
The laser scanner performs multiple functions: it both measures traffic parameters and simultaneously performs self-alignment by analyzing the geometry of the road surface from its reflection signals. This multi-functionality eliminates the need for separate alignment tools or procedures, reducing device complexity while maintaining automation.
3Measurement precision
If the scan plane is not aligned parallel to the road surface, then measurement data cannot be recorded in one plane, but manual alignment is error-prone
Solution Approach 1:
The system uses feedback from the laser scanner's own reflection signals to automatically determine the road surface inclination and adjust the scan plane orientation accordingly. The measurement data from the road surface geometry feeds back into the alignment calculation, enabling precise alignment without complex manual operations.
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 fully automated and accurate alignment of the laser scanner's scan plane relative to the road surface, allowing for precise measurement data collection regardless of the installation location's evenness or level, without the need for special aids or known height information.
Implementation Method 1
The distance of an object located in the scan area is determined from the reflection signals via the pulse transit time measurement
Implementation Method 2
The distance of an object located in the scan area is determined from the reflection signals via the pulse transit time measurement
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The method involves fixing a scanning mirror in a scanning angular position and deriving a displacement value from a reflection signal. A laser scanner (1) is inclined at a scanner longitudinal axis (x') at a predetermined tilting angle, and another displacement value is derived from another reflection signal. A lateral inclination angle is determined from the values and the tilting angle by a trigonometric calculation for reversely tilting the scanner at the tilting angle and tilting the inclination angle, where a scanning plane is aligned parallel to a road plane.