Map Matching Trajectories Using Planned Route Biasing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Map matching processes in transport systems often inaccurately identify road segments due to interference in GPS signals and incorrect or incomplete map data, leading to incorrect route identification and transit information.
Innovation Solution
The transport service system adjusts transition probabilities based on a planned route to determine the most likely map-matched route by penalizing or boosting probabilities of candidate road segments, using algorithms like the Viterbi algorithm and Hidden Markov Model to align GPS data with the planned route, thereby improving the accuracy of route tracking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If map matching is performed using raw GPS coordinates and map data, then the process can identify road segments for vehicle location, but the accuracy of road segment identification deteriorates due to GPS interference and incorrect map data
Solution Approach 1:
The patent introduces planned route information as an intermediary element to bridge the gap between GPS data and map data. This planned route serves as a mediator that helps resolve conflicts between noisy GPS signals and potentially incorrect map data, enabling more accurate road segment identification by providing an additional reference framework
Solution Approach 2:
The patent changes the parameter space by incorporating transition probabilities and planned route constraints into the map matching process. Instead of relying solely on spatial proximity between GPS points and road segments, the system modifies the matching criteria to include temporal and contextual parameters from the planned route, thereby improving identification accuracy
2Measurement precision
If map matching relies solely on GPS location signals and map data, then the system can process location data, but the accuracy deteriorates due to incorrect location coordinates in map data and GPS interference from buildings, vehicles, and weather
Solution Approach 1:
The patent implements a feedback mechanism where the planned route information continuously guides the map matching process. The system uses the planned route as a reference to validate and correct GPS location coordinates, creating a feedback loop that compensates for GPS signal interference from buildings, vehicles, and weather conditions
Solution Approach 2:
The system performs preliminary action by pre-establishing the planned route before executing the map matching process. This advance preparation of route information provides a reference framework that helps correct GPS errors and select accurate road segments even when GPS signals are interfered with by external factors
3Ease of operation
If the map matching process selects road segments based only on spatial proximity to GPS points, then the process is simple, but the selected road segments may not reflect the actual roads traveled by the vehicle
Solution Approach 1:
The patent introduces dynamics by incorporating temporal information and transition probabilities into the map matching process. Instead of a static spatial matching approach, the system dynamically evaluates road segment selections based on the vehicle's planned route and expected transitions, making the matching process adaptive to the actual travel context while maintaining computational feasibility
Data Source
AI summary
A transport service system identifies a map matched trajectory for a transport vehicle based on planned route information and location data associated with a trip. The system receives planned route information and location data for a transport vehicle. For each location data point, the transport service system identifies a set of candidate road segments. Sequential pairs of candidate road segments represent transitions. The system uses a map of the corresponding area to calculate a transition probability, the likelihood of traversing from the first candidate road segment to the second candidate road segment. The system identifies transitions that correspond to the planned route and adjusts the transition probabilities based on the identified planned route transitions. Based on the adjusted probabilities, the transport service system determines a most-likely traversed path for the transport vehicle.