Power Steering Abnormality Detection via Motor Rotation Analysis

Solution Overview

Problem

Conventional power steering apparatuses require a raindrop sensor to detect abnormalities, which increases costs and complexity.

Innovation Solution

The power steering apparatus detects abnormalities based on periodic changes in the number of rotations of an electric motor, steering speed, or steering torque, using existing sensors without the need for an additional abnormality detection sensor.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a raindrop sensor is used to detect abnormalities in the power steering apparatus, then the abnormality detection capability is improved, but the device complexity and cost increase

Engineering Contradiction:

Improveabnormality detection capabilityVSAvoiddevice complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies multi-functionality by enabling existing sensors (rotation sensor, torque sensor, speed sensor) to serve dual purposes: their original functions plus abnormality detection. The control unit analyzes periodic changes in rotation number, steering speed, or steering torque to detect rust or other abnormalities, eliminating the need for a dedicated raindrop sensor while maintaining abnormality detection capability

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system uses self-service by having the control unit independently analyze data from existing sensors to detect abnormalities. The control unit processes rotation numbers, steering speeds, and steering torques to identify periodic changes indicating rust, allowing the system to self-diagnose without external specialized sensors

Inventive Principle:

Principle #25Self-service

2Reliability

If a raindrop sensor is used to detect abnormalities in the power steering apparatus, then the abnormality detection capability is improved, but the manufacturing cost increases

Engineering Contradiction:

Improveabnormality detection capabilityVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent applies multi-functionality by enabling existing sensors (rotation sensor, torque sensor, speed sensor) to serve dual purposes: their original functions plus abnormality detection. The control unit analyzes periodic changes in rotation number, steering speed, or steering torque to detect rust or other abnormalities, eliminating the need for a dedicated raindrop sensor while maintaining abnormality detection capability

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system discards the need for additional specialized sensors (raindrop sensor) and recovers/repurposes existing sensors (rotation, torque, speed sensors) for abnormality detection, thereby reducing component count and manufacturing costs while maintaining detection functionality

Inventive Principle:

Principle #34Discarding and recovering

3Measurement precision

If additional sensors are added to detect abnormalities, then the detection accuracy is improved, but the device complexity increases

Engineering Contradiction:

Improvedetection accuracyVSAvoiddevice complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies feedback by continuously monitoring rotation numbers, steering speeds, and steering torques and analyzing periodic changes in these parameters. The control unit processes this feedback data to detect rust or other abnormalities, achieving accurate detection through data analysis rather than additional sensors

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

The system replaces the mechanical sensor-based detection approach with a signal processing and data analysis approach. Instead of using physical sensors to detect rust directly, the control unit analyzes periodic changes in electrical signals from existing sensors, substituting mechanical detection with electronic signal processing

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS10407092B2Power steering apparatus and control circuit for power steering apparatus

Publication Date: 2019.09.10 ASTEMO LTD

AI summary

A power steering apparatus and a control circuit for a power steering apparatus are provided. The power steering apparatus detects an abnormality in the power steering apparatus based on whether there is a periodic change within a predetermined frequency range with respect to the number of rotations of an electric motor, a steering velocity, or a steering torque.