Vehicle Cruise Control Transition Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle cruise control systems cause driver discomfort when switching from an active to an inactive state, as the transition in target drive force can be abrupt and differ significantly between manual switch operations and brake operations, leading to inconsistent travel conditions.
Innovation Solution
A control device with a system stopper and travel controllers to manage target drive forces, allowing a third target drive force to smoothly transition from an active to an inactive state by varying the change rate based on whether the switch or brake is used, ensuring a comfortable transition by adjusting the power source control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If the target drive force is switched in the same manner both when the cruise control system is stopped by switch operation and brake operation, then the system structure is simple, but the driver may feel discomfort due to significantly different travel conditions
Solution Approach 1:
The patent applies local quality by making the change rate of target drive force specific to different stop conditions. When the follow-up system is stopped by switch operation, a first change rate is used, while when stopped by brake operation, a second change rate is used. This allows the system to have different local characteristics (change rates) for different stopping conditions, resolving the contradiction between simple structure and driver comfort.
Solution Approach 2:
The patent implements dynamics by making the change rate of target drive force variable based on the stop condition. The system dynamically adjusts the change rate according to whether the stop was initiated by switch operation or brake operation, allowing the transition characteristics to adapt to different driving scenarios and reduce driver discomfort.
2Speed
If the target drive force changes abruptly when switching from active to inactive state, then the response is fast, but driver discomfort increases
Solution Approach 1:
The patent applies beforehand cushioning by introducing a transition period with a controlled change rate when switching from active to inactive state. Instead of an abrupt change, the target drive force changes at a predetermined rate that is optimized for driver comfort. This cushioning effect prevents suddenjolts while maintaining reasonable response speed.
Solution Approach 2:
The patent uses parameter changes by adjusting the change rate of target drive force based on the stop condition. The system changes the parameter (change rate) from a fast rate during active operation to a comfort-oriented rate during transition to inactive state, resolving the contradiction between response speed and driver comfort.
Data Source
AI summary
A first travel controller of a control device for a vehicle sets a first target drive force based on preceding vehicle information to control a power source when a follow-up system is in an active state. A second travel controller sets a second target drive force based on a driver's operation to control the power source when the follow-up system is in an inactive state. A third travel controller sets a third target drive force that changes from the first target drive force toward to the second target drive force to control the power source when the follow-up system is switched from the active state to the inactive state. The third travel controller makes a difference between a change rate of the third target drive force set after the cancel operation and a change rate of the third target drive force set after the brake operation.