Moving Body Path Control on Slippery Road Surfaces

Solution Overview

Problem

Existing systems for controlling a moving body to follow a target path on slippery road surfaces suffer from decreased position estimation accuracy due to skidding or wheelspin, leading to potential departure from the target path.

Innovation Solution

A moving body control system that estimates position based on steering angle and speed, acquires road surface slipperiness information, and dynamically adjusts control parameters to suppress departure from the target path.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If position estimation is performed based on steering angle and speed, then the moving body can follow the target path, but position estimation accuracy decreases on slippery road surfaces due to skid or wheelspin

Engineering Contradiction:

Improvetravel control accuracyVSAvoidposition estimation accuracy

Core Design Contradiction:

ReliabilityVSMeasurement precision

Solution Approach 1:

The system performs preliminary acquisition of road surface condition information before executing the travel control process. By obtaining slipperiness data in advance and adjusting control parameters proactively, the system prevents position estimation errors from occurring in the first place, rather than attempting to correct them after they happen.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system incorporates road surface condition information into the control loop, using detected slipperiness levels to dynamically adjust control parameters. This feedback mechanism allows the system to adapt to changing road conditions and maintain accurate position estimation even when skid or wheelspin occurs.

Inventive Principle:

Principle #23Feedback

2Reliability

If control parameters are kept constant, then the control system is simple to operate, but the moving body may depart from the target path on slippery road surfaces

Engineering Contradiction:

Improvepath following accuracyVSAvoidcontrol system complexity

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The system dynamically adjusts control parameters based on real-time road surface condition information. By making the control system adaptive to changing conditions rather than static, the system maintains high path following accuracy on varying road surfaces without requiring complex manual intervention.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The system changes control parameters according to detected road surface slipperiness levels. By modifying operational parameters based on environmental conditions, the system achieves reliable path following on both dry and slippery surfaces while keeping the underlying control logic relatively simple.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If road surface condition information is acquired and control parameters are dynamically adjusted, then departure from target path is suppressed, but the control system becomes more complex

Engineering Contradiction:

Improvetravel control accuracyVSAvoidcontrol system complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The system performs preliminary acquisition of road surface condition information before executing the travel control process. By obtaining slipperiness data in advance and adjusting control parameters proactively, the system prevents position estimation errors from occurring in the first place, rather than attempting to correct them after they happen.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system incorporates road surface condition information into the control loop, using detected slipperiness levels to dynamically adjust control parameters. This feedback mechanism allows the system to adapt to changing road conditions and maintain accurate position estimation even when skid or wheelspin occurs.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS12589743B2Moving body control system and moving body control method

Publication Date: 2026.03.31 TOYOTA JIDOSHA KK

AI summary

A moving body control system controls travel of a moving body in a predetermined. The moving body control system executes: a position estimation process that estimates a position of the moving body based on a steering angle and a speed of the moving body; a travel control process that controls travel of the moving body so as to follow a target path based on the estimated position of the moving body; a road surface condition acquisition process that acquires road surface condition information indicating slipperiness of a target road surface on the target path at least around the moving body; and a departure suppression process that dynamically changes a control parameter used in the travel control process according to the slipperiness of the target road surface such that departure of the moving body from the target path is suppressed.