Lidar Control Method for Echo Pulse Overlay Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lidar systems using coaxial transceivers face accuracy issues due to overlap between echo pulses and stray light echoes, leading to blind areas and reduced ranging accuracy, especially when the echo pulses of the target object overlap with those of the optical window.
Innovation Solution
A control method for lidar that involves emitting a sequence of laser pulses, receiving echo pulses, determining if an overlay is present, and performing re-detection by emitting a second sequence of laser pulses when an overlay is detected, using specific time ranges and thresholds to differentiate between target echoes and stray light echoes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a coded double-pulse detection beam is used for lidar ranging, then the ranging capability is improved, but when the echo pulse overlaps with the echo pulse of stray light, a blind area is formed and ranging accuracy is reduced
Solution Approach 1:
The patent applies preliminary action by performing re-detection in the blind area before finalizing the ranging results. The control module identifies the blind area caused by overlap and conducts an additional detection sequence specifically targeted at this region, ensuring that no detection gaps remain in the final point cloud data.
Solution Approach 2:
The patent implements feedback by using the results from the initial coded double-pulse detection to guide subsequent re-detection. The control module analyzes the first point cloud data to identify blind areas, then uses this information to trigger targeted re-detection sequences, creating a closed-loop detection system that continuously improves coverage.
2Reliability
If re-detection is performed to eliminate blind areas, then detection coverage is improved, but the detection time and system complexity increase
Solution Approach 1:
The patent applies local quality by performing re-detection only in the specific blind area regions identified from the first detection, rather than conducting full-field re-detection. This localized approach minimizes the additional time required while maximizing the improvement in detection coverage where it is most needed.
Solution Approach 2:
The patent uses partial action by conducting re-detection only in the necessary blind area regions rather than performing complete redundant detection of the entire field of view. This selective re-detection approach achieves full coverage with minimal additional time investment.
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 method enhances ranging accuracy and achieves full coverage of the lidar's field of view by effectively addressing blind areas caused by echo pulse overlaps, ensuring accurate detection of target objects within the detection range.
Implementation Method 1
a receiving device not only can receive an echo generated though the laser reflected by an object, but also can receive an echo of stray light generated though the laser directly reflected by an optical window to the receiving device
Implementation Method 2
a coded double-pulse detection beam is used during lidar ranging
Data Source
AI summary
A method for controlling a lidar and a lidar are provided. The method includes: emitting a first sequence of laser pulses, the first sequence of laser pulses including at least a first detection pulse and a second detection pulse coded at a time interval T; receiving a plurality of echo pulses; determining whether an overlay is present among the plurality of echo pulses; and controlling the lidar to emit a second sequence of laser pulses to perform re-detection based on a determination of whether the overlay is present among the plurality of echo pulses.