Vehicle Coasting Control via Deceleration Rate Comparison
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vehicle coasting control systems can implement coasting contrary to the driver's intention, causing anxiety or discomfort, especially in varying traveling environments such as steep hills or traffic conditions.
Innovation Solution
A vehicle control device that determines whether to implement coasting by comparing the required deceleration rate with the coasting deceleration rate, cutting off power transmission between the engine and drive wheels when coasting is deemed appropriate, and maintaining power transmission otherwise, using sensors and infrastructure information to assess deceleration needs and road conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If coasting control is implemented based on conventional techniques (accelerator depression amount and clutch revolution speed), then fuel consumption is reduced, but driver comfort deteriorates due to unexpected deceleration contrary to driver intention
Solution Approach 1:
The system continuously monitors accelerator depression amount, brake operation state, and vehicle speed to dynamically determine whether coasting should be executed. This feedback mechanism allows the system to adapt to driver intentions and road conditions, preventing unwanted coasting while maintaining fuel efficiency benefits
Solution Approach 2:
The coasting control determination is made dynamic by considering multiple varying parameters including accelerator depression amount, brake operation state, and vehicle speed. The system adjusts coasting execution in real-time based on the combination of these parameters, rather than using fixed thresholds
2Use of energy by moving object
If coasting is executed without considering required deceleration rate, then fuel economy improves, but deceleration performance deteriorates when driver intends faster deceleration
Solution Approach 1:
The system calculates the required deceleration rate in advance by considering road gradient, vehicle speed, and brake operation state before executing coasting. This preliminary assessment ensures that coasting is only performed when it will not compromise the required deceleration performance
Solution Approach 2:
The system prevents coasting execution when the calculated required deceleration rate indicates that the driver intends to decelerate faster than what coasting alone can provide. This preliminary anti-action blocks the coasting control before it can negatively impact deceleration performance
Data Source
AI summary
A vehicle control device is a vehicle control device for a vehicle capable of coasting, in which when there is no acceleration or deceleration request to the vehicle while traveling, power transmission between an engine and drive wheels is cut off and the vehicle is allowed to travel by inertia, wherein in a state in which there is no acceleration or deceleration request to the vehicle while traveling and power is transmitted between the engine and the drive wheels, whether or not to implement the coasting is determined by comparing a required deceleration rate Dt which is estimated as a deceleration rate to be later required of the vehicle and a coasting deceleration rate Dn which is estimated as a deceleration rate during the coasting. Where it is determined to implement the coasting, power transmission between the engine and the drive wheels is cut off and the coasting is implemented, and where it is determined not to implement the coasting, power transmission between the engine and the drive wheels is maintained. As a result, the implementation of coasting that can provide a sense of anxiety or discomfort to the driver can be suppressed.