Active-Link Suspension With Switchable Cross-Vehicle Spring Constraint
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle suspension systems lack the ability to dynamically adjust wheel constraint strategies to accommodate different driving modes, such as comfort and race modes, due to limited displacement ranges and packaging constraints.
Innovation Solution
A vehicle suspension system incorporating a cross-vehicle spring and active links that can switch between modes to either permit or constrain the motion of suspension linkages, allowing for variable stiffness and enhanced wheel control, using a torsion bar with adjustable active links and fluid pathways to manage constraint and motion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the suspension linkage is designed to permit wheel motion to isolate the vehicle body from wheel displacements, then passenger comfort is improved, but the displacement range is limited due to packaging constraints
Solution Approach 1:
The active link incorporates a variable restriction mechanism that can dynamically change between restricted and unrestricted states, allowing the suspension system to adapt its characteristics in real-time. This enables the system to provide both comfort-oriented motion isolation and performance-oriented constraint as needed
Solution Approach 2:
The system changes the physical state of the fluid pathway restriction to alter the suspension behavior. By transitioning the variable restriction between open and closed positions, the system modifies the effective stiffness and motion characteristics of the suspension linkage
2Reliability
If a damper is used to constrain suspension linkage motion, then wheel motion control is improved, but the system cannot adapt to different driving modes
Solution Approach 1:
The active link with variable restriction provides dynamic adaptability by allowing the system to switch between different operational states. In comfort mode, the restriction is open allowing motion; in performance mode, the restriction closes to constrain motion, enabling adaptation to different driving requirements
Solution Approach 2:
The active link mechanism serves multiple functions: it acts as a mechanical connector, a motion constraint device, and a mode-switching element. This multi-functionality allows a single component to address both comfort and performance requirements across different driving scenarios
3Reliability
If the cross-vehicle spring is used to constrain motion of suspension linkages, then vehicle performance is improved, but passenger comfort deteriorates
Solution Approach 1:
The system dynamically activates or deactivates the cross-vehicle spring constraint through the active link mechanism. In performance mode, the spring is activated to provide rigid constraint; in comfort mode, the mechanism allows the spring to remain inactive, providing a softer ride
Solution Approach 2:
The system changes the effective stiffness parameter of the suspension by controlling whether the cross-vehicle spring is engaged. The variable restriction mechanism allows transition between a compliant state (comfort) and a rigid constrained state (performance)
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
Enables the suspension system to adapt to different driving conditions by providing tailored wheel constraint strategies, enhancing passenger comfort or vehicle performance as needed, while maintaining effective motion control.
Implementation Method 1
a cross-vehicle spring having a first attachment point coupled to the first suspension linkage and a second attachment point coupled to the second suspension linkage
Implementation Method 2
a fluid pathway connected between the first volume and the second volume, the fluid pathway comprising a variable restriction
Data Source
AI summary
A vehicle comprising: a vehicle body; first and second wheel assemblies each having a rotation axis; first and second suspension linkages, each suspension linkage coupling a respective wheel assembly to the vehicle body to permit motion of the rotation axis of that wheel assembly relative to the vehicle body; a cross-vehicle spring having a first attachment point coupled to the first suspension linkage and a second attachment point coupled to the second suspension linkage; and a first active link coupling the first attachment point to the first suspension linkage, the first active link being configured to have: (i) a first mode in which the first active link permits motion of the first suspension linkage relative to the first attachment point to prohibit the cross-vehicle spring from constraining motion of the first and second suspension linkages; and (ii) a second mode in which the active link fixes the motion of the first suspension linkage relative to the first attachment point so that the cross-vehicle spring constrains motion of the first and second suspension linkages during common motion of the first and second suspension linkages.