Model-Free Reinforcement Learning for Autonomous Vehicle Navigation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Traditional planning and control methods for autonomous vehicles fail to find feasible trajectories in dense traffic scenarios due to the small obstacle-free volume in space-time, making it difficult for them to navigate effectively.

Innovation Solution

A model-free reinforcement learning system is developed, utilizing a processor and memory to simulate traffic scenarios with an actor-critic network, which includes a kinematic bicycle model for vehicles and traffic participants, and uses occupancy, relative velocity, displacement, and heading maps to generate policies for autonomous vehicle navigation, allowing for continuous control and smoother motion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional planning and control methods are used for autonomous vehicle navigation, then the system structure is simple and easy to implement, but the system fails to find feasible trajectories in dense traffic scenarios due to small obstacle-free volume

Engineering Contradiction:
Improveability to find feasible trajectoryVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces traditional mechanical planning and control methods with a model-free reinforcement learning system. The autonomous vehicle uses neural networks (actor-critic architecture) to learn optimal navigation policies from simulated traffic scenarios, substituting deterministic algorithms with data-driven learning approaches that can adapt to dense traffic conditions where traditional methods fail

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The system performs preliminary training in a simulated environment before real-world deployment. Extensive simulations generate training data that pre-trains the reinforcement learning models, allowing the vehicle to learn complex navigation strategies in advance. This preliminary action in simulation enables the system to handle real dense traffic scenarios effectively without requiring complex real-time computation

Inventive Principle:
Principle #10Preliminary action

2Reliability

If model-free reinforcement learning is used to navigate dense traffic, then the ability to find feasible trajectories improves, but the computational cost and complexity of the system increases

Engineering Contradiction:
Improvenavigation feasibilityVSAvoidcomputational complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent creates a simplified copy of the real traffic environment through simulation. The simulated traffic scenario replicates essential dynamics and interactions without the full complexity of real-world conditions. This copying approach allows extensive training data generation at low computational cost, enabling the reinforcement learning system to learn complex policies offline before deployment

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The system uses periodic training updates where the reinforcement learning models are retrained at intervals using newly collected simulation or real-world data. This periodic action allows the system to adapt to changing traffic patterns and improve performance over time without requiring continuous complex computation during normal operation

Inventive Principle:
Principle #19Periodic action

3Ease of operation

If continuous control policies are used for autonomous vehicle navigation, then the smoothness of motion improves, but the difficulty of detecting and measuring optimal control actions increases

Engineering Contradiction:
Improvesmoothness of motionVSAvoiddifficulty of determining optimal control
Core Design Contradiction:
Ease of operationVSDifficulty of detecting and measuring

Solution Approach 1:

The actor-critic reinforcement learning architecture implements continuous feedback mechanisms. The critic network evaluates the quality of actions taken by the actor network, providing gradient feedback that guides policy improvement. This feedback loop enables the system to learn optimal continuous control policies that produce smooth motion while systematically improving performance through evaluated feedback from simulated and real-world operations

Inventive Principle:
Principle #23Feedback

Data Source

PatentUS11465650B2Model-free reinforcement learning
Publication Date: 2022.10.11 HONDA MOTOR CO LTD
  • US11465650B2 patent drawing
  • US11465650B2 patent drawing
  • US11465650B2 patent drawing

AI summary

A system for generating a model-free reinforcement learning policy may include a processor, a memory, and a simulator. The simulator may be implemented via the processor and the memory. The simulator may generate a simulated traffic scenario including two or more lanes, an ego-vehicle, a dead end position, and one or more traffic participants. The dead end position may be a position by which a lane change for the ego-vehicle may be desired. The simulated traffic scenario may be associated with an occupancy map, a relative velocity map, a relative displacement map, and a relative heading map at each time step within the simulated traffic scenario. The simulator may model the ego-vehicle and one or more of the traffic participants using a kinematic bicycle model. The simulator may build a policy based on the simulated traffic scenario using an actor-critic network. The policy may be implemented on an autonomous vehicle.