Identical Double Wishbone Suspension Arms for Kinematic Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional double wishbone suspension systems require different length upper and lower wishbones to achieve appropriate camber angles and minimize halftrack change, leading to increased component complexity and costs, while also potentially causing excessive tyre wear and undesirable drive feel.

Innovation Solution

The use of identical upper and lower control arms with carefully chosen mounting points and arc positions to control wheel kinematics, reducing the need for different components and minimizing halftrack change, thereby achieving suitable camber angles and dynamic performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If different length upper and lower wishbones are used to achieve appropriate camber angles, then wheel contact with surface is improved, but component complexity and costs increase

Engineering Contradiction:
Improvewheel contact with surfaceVSAvoidcomponent complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent applies homogeneity by making the upper and lower control arms identical in shape, construction, and material. This single-type control arm design maintains appropriate camber angles and wheel contact with the surface while eliminating the complexity of managing different component specifications, inventory, and assembly procedures for multiple control arm types

Inventive Principle:
Principle #33Homogeneity

2Manufacturing precision

If different length upper and lower wishbones are used to control wheel arc travel, then camber angle control is improved, but manufacturing costs increase

Engineering Contradiction:
Improvecamber angle controlVSAvoidmanufacturing costs
Core Design Contradiction:
Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The patent changes the mounting parameters (positions and orientations) of the identical control arms on the chassis to achieve the desired camber angle control and wheel arc travel. By adjusting where and how the control arms are mounted rather than changing their dimensions, the system maintains precise camber control while using a single, easier-to-manufacture control arm design

Inventive Principle:
Principle #35Parameter changes

3Device complexity

If short wishbones traveling on small arcs are used, then device simplicity is improved, but halftrack change increases causing tyre wear

Engineering Contradiction:
Improvedevice simplicityVSAvoidtyre wear
Core Design Contradiction:
Device complexityVSObject-generated harmful factors

Solution Approach 1:

The patent resolves the contradiction by moving from varying control arm lengths (one-dimensional solution) to optimizing mounting point positions and orientations in three-dimensional space. The identical control arms are mounted at specific locations and angles on the chassis that create the appropriate arc travel paths, achieving large enough arcs to minimize halftrack change and tyre wear while maintaining device simplicity

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

4Device complexity

If identical upper and lower control arms are used, then component inventory is reduced, but achieving appropriate wheel kinematics becomes more difficult

Engineering Contradiction:
Improvecomponent inventoryVSAvoidwheel kinematics optimization
Core Design Contradiction:
Device complexityVSDifficulty of detecting and measuring

Solution Approach 1:

The patent addresses the difficulty of optimizing wheel kinematics with identical control arms by systematically varying mounting parameters including the vertical and horizontal positions of upper and lower mounting points, the orientation angles of the control arms, and the length of the support member. These parameter adjustments allow precise control of wheel arc travel, camber gain, and halftrack change while maintaining the simplicity of using identical control arms

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3478520A1Vehicle suspension system
Publication Date: 2019.05.08 ARRIVAL UK LTD

AI summary

A vehicle chassis having upper and lower mounting points thereon and an independent double control arm suspension arrangement for mounting a wheel to the chassis. The independent double control arm suspension arrangement comprises an upper control arm and a lower control arm each having an identical shape and construction. The upper control arm has an upper pivot end and the lower control arm has a lower pivot end. The upper pivot end is attached to the upper mounting point and the lower pivot end is attached to the lower mounting point such that the upper control arm and upper control arm can pivot relative to the chassis and an upper oscillatory end and a lower oscillatory end are capable of oscillating along a fixed arc defined by the upper control arm and lower control arm respectively. A support for the wheel is connected to the upper oscillatory end and the lower oscillatory end.