Steering Angle Control Interpolation Abnormal Value Detection

Solution Overview

Problem

Existing steering-angle control systems face challenges in smoothly changing steering angles, especially when there are large differences between consecutive steering-angle command values, and in preventing abnormal steering angles when state command values become abnormal.

Innovation Solution

A steering-angle control apparatus that interpolates between previous and current state command values to compute a target steering-angle value in a shorter interpolation period, determines if this value is abnormal, and controls the steering mechanism based on either the interpolated value or the current command value depending on its abnormality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If steering-angle control is based on state command values input in each predetermined period, then the steering mechanism can be controlled according to command values, but the steering angle cannot be smoothly changed when there are large differences between consecutive command values

Engineering Contradiction:

Improvesmoothness of steering angle changeVSAvoidprevention of abnormal steering angles

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The interpolation unit performs preliminary computation by interpolating between previous and current state command values to generate intermediate target steering-angle values before the actual steering control is executed. This preliminary action smooths out abrupt changes and prevents wobbling while maintaining control accuracy.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The interpolation unit acts as an intermediary between the state command values and the steering mechanism control. It computes intermediate target steering-angle values that bridge the gap between consecutive command values, ensuring smooth transitions and preventing direct transmission of abnormal values to the steering mechanism.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Speed

If the steering mechanism is controlled based on current state command values, then the steering angle responds to current commands, but abnormal steering angles may be controlled when state command values are abnormal

Engineering Contradiction:

Improveresponse speed to steering commandVSAvoidprevention of abnormal steering angle control

Core Design Contradiction:

SpeedVSReliability

Solution Approach 1:

The interpolation unit performs preliminary computation by interpolating between previous and current state command values to generate intermediate target steering-angle values before the actual steering control is executed. This preliminary action smooths out abrupt changes and prevents wobbling while maintaining control accuracy.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The interpolation unit acts as an intermediary between the state command values and the steering mechanism control. It computes intermediate target steering-angle values that bridge the gap between consecutive command values, ensuring smooth transitions and preventing direct transmission of abnormal values to the steering mechanism.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Ease of operation

If interpolation is performed between previous and current state command values, then smooth steering angle changes are achieved, but additional computation is required

Engineering Contradiction:

Improvesmoothness of steering angle changeVSAvoidcontrol apparatus structure

Core Design Contradiction:

Ease of operationVSDevice complexity

Solution Approach 1:

The interpolation unit utilizes the existing previous and current state command values to compute intermediate target steering-angle values through interpolation. This self-service approach leverages available data without requiring external complex processing, achieving smooth transitions with minimal additional computational overhead.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS12286170B2Steering-angle control apparatus

Publication Date: 2025.04.29 DENSO CORP

AI summary

A steering-angle control apparatus controls a steering mechanism based on a state command value, which is input in each predetermined period. An interpolation unit interpolates between a previous value and a current value of the input state command value to compute a state interpolation value in an interpolation period, which is shorter than the predetermined period. An interpolation-value determination unit determines whether the state interpolation value is an abnormal value. A control unit controls the steering mechanism based on the state interpolation value computed by the interpolation unit when the interpolation-value determination unit determines that the state interpolation value is not an abnormal value, and controls the steering mechanism based on the current value of the state command value when the interpolation-value determination unit determines that the state interpolation value is an abnormal value.