Shift by Wire Parking Control via Electronic Brake Relay
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing shift by wire (SBW) devices in vehicles increase manufacturing cost and weight, making them less competitive and less fuel-efficient, and complicate the parking process due to the need for multiple shift stages and mechanical connections.
Innovation Solution
A system that omits the transmission parking configuration by using cooperative control between an electronic shift by wire device and an electronic parking brake, allowing for direct operation of the brake via a relay when the electronic parking brake fails, and includes a backup communication line for secure operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a shift by wire (SBW) device is applied to replace mechanical transmission components, then the parking process is simplified and mechanical connections are reduced, but manufacturing cost and vehicle weight increase
Solution Approach 1:
The patent combines the parking control function with the electronic parking brake system. The SBW device sends a parking control request to the electronic parking brake controller, which then actuates the parking brake to hold the vehicle. This merging of functions eliminates the need for a separate transmission parking mechanism, simplifying the parking process while avoiding additional weight from redundant mechanical components.
Solution Approach 2:
The electronic parking brake system is designed to serve multiple functions: it acts as both a service brake and a parking brake mechanism. The same electronic parking brake controller and actuator that provide stopping force during driving are also used to maintain parking position, eliminating the need for dedicated parking-specific mechanical components that would increase weight.
2Ease of operation
If a shift by wire (SBW) device is applied to replace mechanical transmission components, then the parking process is simplified and mechanical connections are reduced, but manufacturing cost increases
Solution Approach 1:
The patent merges the parking control function with the existing electronic parking brake system, eliminating the need for separate parking control hardware. The SBW device communicates with the electronic parking brake controller through existing communication buses, and the same actuators are used for both service braking and parking, thereby reducing component count and manufacturing costs despite adopting SBW technology.
Solution Approach 2:
The electronic parking brake system is designed with multi-functionality, serving both as a service brake and parking brake mechanism. This universal design allows a single system to perform multiple functions that would traditionally require separate mechanical components, thereby reducing overall system cost while enabling simplified SBW-based parking control.
3Weight of moving object
If the electronic parking brake is used to replace transmission parking configuration, then vehicle weight and manufacturing cost are reduced, but system reliability may be compromised due to potential failure events
Solution Approach 1:
The patent implements a backup communication line between the SBW device and the electronic parking brake controller, independent of the central gateway. This redundant communication path ensures that parking control requests can still reach the electronic parking brake even if the primary communication through the central gateway fails, thereby maintaining system reliability without requiring additional mechanical backup components that would increase weight.
Solution Approach 2:
The patent introduces a relay as an intermediary component in the communication path between the SBW device and the electronic parking brake controller. The relay can directly transmit parking control requests when the electronic parking brake controller is unavailable or fails, ensuring that the parking function remains operational. This intermediary mechanism provides reliability assurance without requiring heavy mechanical backup systems.
Data Source
AI summary
A system for parking control of a vehicle in which a transmission parking configuration is omitted is provided. The system includes a shift by wire device that requests a parking control of the vehicle when a parking stage is input by an operation of a driver. An electronic parking brake operates a brake installed on a drive wheel via a relay which is connected to be in a parking brake state when the electronic parking brake receives the parking control request from the shift by wire device. The shift by wire device switches the relay to directly operate the brake to be in the parking brake state when the shift by wire device receives a failure event, which indicates that a normal operation of the electronic parking brake is impossible, from the electronic parking brake.