Vehicle Control Circuit Restart Synchronization During Power Latch

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In steer-by-wire steering systems, the mismatched recognition of vehicle power-on timings by control arithmetic units during power latch control can lead to unintended arithmetic results and state transitions, causing inappropriate control of reaction and turning actuators, which may discomfort the driver.

Innovation Solution

A control device with multiple control circuits that synchronize their starting after all units recognize power-on, using flags to confirm synchronization and reducing direct communication paths to match starting timings, ensuring coordinated control of reaction and turning motors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If control arithmetic units individually perform power latch control and restart after powering on, then each unit operates independently, but mismatched recognition timings cause unintended arithmetic results and state transitions

Engineering Contradiction:
Improvecontrol synchronizationVSAvoidcontrol circuit coordination
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent merges the power-on recognition and restart control of multiple control arithmetic units into a unified process. By requiring all units to recognize power-on and complete restart before system operation begins, the invention ensures synchronized control while maintaining individual unit independence during the recognition phase.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The invention implements preliminary synchronization action by requiring all control arithmetic units to complete their power-on recognition and restart processes before the system transitions to normal operation. This preliminary coordination prevents mismatched timing issues that would otherwise cause unintended arithmetic results and state transitions during actual control operations.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If control arithmetic units restart at different timings due to wiring resistance differences, then individual unit operation is maintained, but control coordination and driver comfort are compromised

Engineering Contradiction:
Improvecontrol coordinationVSAvoiddriver comfort
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The patent merges the operation timing of multiple control arithmetic units by implementing a unified restart condition. All units must complete their individual power-on recognition and restart processes before the system allows normal operation to begin, ensuring that control coordination is maintained while preserving the ease of operation for the driver.

Inventive Principle:
Principle #5Merging (Combining)

3Device complexity

If power latch control is performed individually by each control arithmetic unit, then unit independence is maintained, but synchronized control and system reliability are reduced

Engineering Contradiction:
Improvecontrol circuit independenceVSAvoidsystem control reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The invention implements preliminary synchronized action by requiring all control arithmetic units to complete their power-on recognition and restart processes before the system transitions to normal operation. This preliminary coordination ensures that while units maintain their operational independence, they all reach a synchronized state before control operations begin, thereby ensuring system reliability.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4166422B1Control device for vehicle
Publication Date: 2025.11.05 JTEKT CORP
  • EP4166422B1 patent drawingFigure 1
  • EP4166422B1 patent drawingFigure 2
  • EP4166422B1 patent drawingFigure 3

AI summary

A control device for a vehicle includes a plurality of control circuits (41A, 42A, 51A, 52A) configured to control a control object by starting in response to powering-on of a vehicle and to perform power latch control for continuing to be supplied with electric power in a predetermined period in response to powering-off of the vehicle. Each of the control circuits (41A, 42A, 51A, 52A) is configured to perform starting after all of the control circuits (41A, 42A, 51A, 52A) have recognized the powering-on of the vehicle in a case where the vehicle is powered on while the power latch control is being performed after the vehicle has been powered off.