Lane Network Graph for Vehicle Tracking Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Two-dimensional tracking systems face instability and tuning challenges due to arbitrary target motion, making it difficult to model and implement effectively, especially in automotive applications where sensors provide asynchronous data with varying characteristics.

Innovation Solution

A lane network graph is used to restrain target motion, integrating data from lidar and radar sensors by projecting observations onto a graph network, leveraging sensor characteristics to filter out noise and estimate target position using a Kalman filter, while synchronizing observations and correcting for time delays.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a two-dimensional tracking system is used to track targets in open space, then the system can detect targets at any position, but the system becomes unstable and difficult to tune due to arbitrary motion patterns

Engineering Contradiction:
Improvetarget position coverageVSAvoidtracking stability
Core Design Contradiction:
Adaptability or versatilityVSReliability

Solution Approach 1:

The patent segments the two-dimensional tracking space into one-dimensional lane segments based on road network graphs. Instead of tracking targets in continuous 2D space, the system divides the space into discrete lane segments that targets must follow, making the tracking problem more manageable and stable while preserving the ability to detect targets at various positions along these segments

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces a road network graph as an intermediary structure between the sensors and the tracking algorithm. This graph serves as a mediator that constrains and organizes target positions along realistic vehicle paths, transforming the arbitrary 2D motion problem into a structured 1D motion problem along graph edges while maintaining versatility in detecting targets at different locations

Inventive Principle:
Principle #24Intermediary (Mediator)

2Adaptability or versatility

If data from multiple sensors with different modalities is integrated, then the tracking system can leverage diverse sensor characteristics, but the system becomes complex in handling asynchronous data with varying time delays and accuracy

Engineering Contradiction:
Improvesensor data integrationVSAvoiddata integration complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent performs preliminary actions by predicting target positions at standardized timestamps before integrating sensor data. The system uses motion models to predict where targets should be at specific time points, then compares these predictions with actual sensor observations. This preliminary prediction step simplifies the integration of asynchronous data from multiple sensors by providing a common reference framework

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes the temporal parameters of sensor data by resampling asynchronous observations to synchronized timestamps. Instead of dealing with the original asynchronous timing of each sensor, the system transforms all sensor inputs to a common time reference frame using prediction and interpolation, thereby simplifying the integration process while preserving the complementary information from different sensor modalities

Inventive Principle:
Principle #35Parameter changes

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 approach results in a more efficient and robust tracking system that correctly integrates sensor data, reduces false targets, and enables accurate obstacle detection and collision avoidance in autonomous vehicles.

Implementation Method 1

The first sensor can be a lidar sensor

Methodology Applied
Scientific EffectLight: Light

Implementation Method 2

The second sensor can be a radar sensor

Methodology Applied
Scientific EffectRadar: Radar

Data Source

PatentUS9255989B2Tracking on-road vehicles with sensors of different modalities
Publication Date: 2016.02.09 TOYOTA JIDOSHA KK
  • US9255989B2 patent drawing
  • US9255989B2 patent drawing
  • US9255989B2 patent drawing

AI summary

A vehicle system includes a first sensor and a second sensor, each having, respectively, different first and second modalities. A controller includes a processor configured to: receive a first sensor input from the first sensor and a second sensor input from the second sensor; detect, synchronously, first and second observations from, respectively, the first and second sensor inputs; project the detected first and second observations onto a graph network; associate the first and second observations with a target on the graph network, the target having a trajectory on the graph network; select either the first or the second observation as a best observation based on characteristics of the first and second sensors; and estimate a current position of the target by performing a prediction based on the best observation and a current timestamp.