Shared-Shaft Steer-By-Wire Packaging for Redundant Rack Actuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mechanical steering systems in vehicles require a mechanical linkage between the steering wheel and road wheels, which can be replaced by electrically driven steer-by-wire systems to eliminate physical connections and provide advanced steering features, but these systems need to replicate the steering feel and functionality of conventional systems.
Innovation Solution
A steer-by-wire system with first and second motor assemblies sharing a common shaft, a rotary-to-linear conversion mechanism, and a single package with a seal to accommodate both motors, along with belt and gear configurations to ensure reliable operation and feedback, including inductive and magnetic sensors for position detection.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple motor assemblies are used in steer-by-wire system, then reliability and redundancy are improved, but device complexity and space requirements increase
Solution Approach 1:
The patent combines multiple motor assemblies (first and second motor assemblies) to share a common shaft, thereby achieving redundancy and improved reliability while reducing overall system complexity and space requirements compared to using completely separate motor systems
Solution Approach 2:
The common shaft serves multiple functions by being coupled to both the first and second motor assemblies simultaneously, allowing a single component to perform multiple roles in the steer-by-wire system and reducing the total number of parts needed
2Volume of moving object
If motor assemblies are placed in single package, then space efficiency is improved, but manufacturing precision and sealing requirements increase
Solution Approach 1:
The first and second motor assemblies are merged into a single package housing, improving space efficiency and volume utilization while maintaining functional separation through internal sealing mechanisms
Solution Approach 2:
A seal is introduced as an intermediary component between the first and second motor assemblies within the single package, preventing contamination and maintaining precise operational boundaries despite the close proximity of multiple motor components
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
The system provides accurate steering feel and feedback, even in electronic failures, with redundant mechanisms to ensure continuous operation and precise control of road wheel movement.
Implementation Method 1
an inductive sensor configured to sense a position of the common shaft
Implementation Method 2
a magnetic sensor configured to sense a position of the common shaft
Data Source
AI summary
A steer-by-wire system may comprise: first and second motor assemblies having one common shaft; a single package having an inside space accommodating the first and second motor assemblies; a steering rack configured to be linearly movable in response to rotation of the one common shaft of the first and second motor assemblies; and a rotary-to-linear conversion mechanism operably connected between the one common shaft of the first and second motor assemblies and the steering rack and configured to convert a rotary motion of the one common shaft of the first and second motor assemblies into a linear motion for linearly moving the steering rack. A seal may be positioned between the first motor assembly and the second motor assembly in the inside space of the single package.