Vehicle Control Device Shift Position Abnormality Handling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shift-by-wire vehicle control systems face limitations when an abnormality occurs, as they fail to release the parking lock effectively, leading to restricted vehicle movement due to unresolved sensor discrepancies, which can result in unintended immobilization.
Innovation Solution
A vehicle control device with an actuator that includes an abnormality detection mechanism, shift-operation determination, and movement prevention control, allowing the actuator to release movement prevention when the shift operating device is operated by the driver, even if there is an abnormality in the shift position detection sensors, ensuring safe and intentional vehicle movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the vehicle control device executes fail-safe processing by switching the driving range to P range when sensor detection results do not coincide, then the reliability of the control system is improved, but the vehicle movement is restricted due to the parking lock being applied and unable to be released
Solution Approach 1:
The control device changes the control parameter (parking lock state) based on the detected abnormality condition. When sensor discrepancies are detected, the system transitions to a fail-safe mode where the parking lock is applied and subsequently released based on shift operating device position, rather than maintaining normal control logic. This parameter change resolves the contradiction by adapting the control strategy to the abnormal condition.
Solution Approach 2:
The system dynamically adjusts the parking lock control based on the shift operating device's detected position. The parking lock is released when the shift operating device is detected at a position other than the parking position, even during fail-safe processing. This dynamic adjustment allows the vehicle to be moved for diagnostic purposes while maintaining reliability improvements from the fail-safe processing.
2Object-affected harmful factors
If the parking lock mechanism is activated to prevent vehicle movement during abnormality, then the safety is improved, but the vehicle becomes immobilized and cannot be moved for diagnostic or recovery purposes
Solution Approach 1:
The control device changes the parking lock control parameter based on the shift operating device position detection. When an abnormality is detected and fail-safe processing is executed, the system monitors the shift operating device position and releases the parking lock when a specific position (non-parking position) is detected. This allows the vehicle to be moved under controlled conditions even during abnormality, resolving the contradiction between safety and adaptability.
Solution Approach 2:
The shift operating device position detection acts as an intermediary condition for controlling the parking lock release during fail-safe processing. Rather than directly allowing or preventing vehicle movement, the system uses the shift operating device position as a mediator to determine when the parking lock should be released, enabling controlled mobility during abnormality while maintaining safety.
3Measurement precision
If the control device requires coincidence of detection results from multiple sensors to operate, then the measurement precision is improved, but the system complexity increases and may lead to false abnormality detection
Solution Approach 1:
The control device changes the control logic parameter when sensor discrepancies are detected. Instead of requiring continuous coincidence of all sensor readings, the system transitions to a mode where the shift operating device position becomes the primary control parameter for parking lock release decisions. This parameter change reduces the impact of sensor complexity while maintaining adequate detection precision for safe operation.
Data Source
AI summary
A vehicle control device includes: an abnormality detecting portion that detects an abnormality in at least part of a shift position detection portion detecting a shift position; a shift-operatoin determining portion that determines, based on a detection signal from the shift position detection portion, whether a shift operating device is shift-operated or not by a driver, and a vehicle movement prevention control portion that, in a case where a movement of a vehicle is prevented by an actuator and in a case where the abnormality in part of the shift position detection portion is detected by the abnormality detecting portion, permits the actuator to release the prevention of the movement of the vehicle if it is determined by the shift-operation determining portion that the shift operating device is shift-operated by the driver.