Vehicle Powertrain Freewheeling Control for Brake-Assisted Engine Restart
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional internal combustion engine vehicles consume unnecessary fuel and emit excess pollutants due to continuous operation during idling and inactivity, and existing stop-and-start systems lack reliability in restarting the engine during emergency braking on slippery surfaces while maintaining vehicle control.
Innovation Solution
A computer system controls a powertrain system to operate in a freewheeling mode with engine shutdown, utilizing energy from drive wheels for reliable engine restart by delaying brake activation, especially during emergency braking, and using a controllable clutch for torque transfer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If the engine is shut down during freewheeling mode to save fuel and reduce emissions, then fuel consumption and pollution are reduced, but the reliability of engine restart during emergency braking deteriorates
Solution Approach 1:
The system dynamically switches between engine stop and engine running states based on detected braking situations. When emergency braking is detected, the system transitions from engine stop state to engine running state, making the system adaptable to different operational conditions while maintaining fuel efficiency during normal freewheeling operation
Solution Approach 2:
The control system continuously monitors braking system activation signals and uses this feedback to determine whether to restart the engine. When a braking situation is detected through the braking system signal, the control system triggers engine restart, creating a closed-loop control mechanism that responds to real-time operational needs
2Reliability
If the engine is restarted during emergency braking on slippery surfaces, then vehicle control and power steering effectiveness are maintained, but simultaneous brake activation and engine restart cause reduced vehicle control
Solution Approach 1:
The system delays brake activation until after the engine has successfully restarted. This preliminary engine restart action ensures that the engine is running and providing power steering effectiveness before the braking force is applied, preventing the simultaneous activation problem that would compromise vehicle control on slippery surfaces
Solution Approach 2:
The system prepares the engine for restart before applying brake force by detecting the braking situation in advance and initiating the restart sequence. This beforehand preparation cushions against the potential harm of simultaneous activation by ensuring the engine is ready to provide power steering support when braking begins
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Improves engine startup reliability on slippery surfaces, maintains vehicle stability, and enhances drivability and safety by effectively using drive wheel energy for restart, avoiding simultaneous brake activation issues.
Implementation Method 1
restarting the engine by using a controllable clutch
Implementation Method 2
identify, in the freewheeling mode, a braking situation for the vehicle requiring an activation of braking of the one or more drive wheels
Data Source
AI summary
The present disclosure relates to a computer system for controlling a powertrain system of a vehicle, the powertrain system including an internal combustion engine connectable to one or more drive wheels, the computer system including processing circuitry configured to selectively operate the powertrain system in at least a freewheeling mode (ES-FM), the processing circuitry further being in communication with a braking system for the vehicle, wherein the processing circuitry is configured to: determine, in the freewheeling mode, a need for restarting the engine; identify, in the freewheeling mode, a braking situation for the vehicle requiring an activation of braking of the one or more drive wheels; cancel the activation of braking of the one or more drive wheels or determine to decrease the braking operation in response to the determined need for restarting the engine; and restart the engine in response to the cancelation or the decreased braking operation.