Engine Auto-Stop Control Under Vehicle Speed Sensor Failure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle control systems that rely on vehicle speed sensors for determining stopped states may incorrectly stop the engine when the sensor fails, leading to increased fuel consumption and emissions due to the engine not being turned off when the vehicle is not actually stopped.
Innovation Solution
A vehicle control device that includes a vehicle speed detection unit and an automatic engine stop unit, which prohibits automatic engine stop when a failure of the vehicle speed detection unit is detected, and provides distinct notification modes to alert the driver when engine stop is prohibited.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If automatic engine stop is implemented based on vehicle speed detection, then fuel consumption is reduced, but reliability deteriorates due to sensor failure causing unintended shutdowns
Solution Approach 1:
The system performs beforehand cushioning by detecting sensor failures in advance and prohibiting automatic engine stop when failures are detected. The failure detection unit continuously monitors the vehicle speed detection unit, and when a failure is detected, the system preemptively disables the automatic stop function to prevent unintended engine shutdowns, thus cushioning against reliability issues before they occur
Solution Approach 2:
The failure detection unit acts as an intermediary between the vehicle speed detection unit and the automatic engine stop unit. It monitors the detection unit's output and mediates by prohibiting the stop unit from operating when sensor failures are detected, thus preventing the transmission of erroneous stop commands while allowing normal operation when sensors function correctly
2Extent of automation
If vehicle speed detection is used to determine stopped state, then automation is improved, but measurement precision deteriorates when sensor fails
Solution Approach 1:
The system implements feedback by having the failure detection unit continuously monitor the vehicle speed detection unit's output signals. When the detection unit fails to provide valid speed information or provides abnormal readings, the feedback mechanism triggers a prohibition of automatic engine stop, thus maintaining measurement precision by relying on feedback from the monitoring system
Solution Approach 2:
The vehicle speed detection unit performs self-service by including an integrated failure detection capability. The detection unit monitors its own operational status and automatically provides failure information to the control unit, enabling the system to self-diagnose and self-protect without external intervention
Data Source
AI summary
The present invention is applied to a control device for controlling a vehicle that travels using a driving force of an engine. The control device for the vehicle includes the vehicle speed detection unit that detects the vehicle speed, and the automatic engine stop unit that performs the automatic engine stop after a prescribed time elapses from when the vehicle speed detection unit detects that the vehicle is in the stopped state. When a failure of the vehicle speed detection unit is detected, the automatic engine stop by the automatic engine stop unit is prohibited.