Active Noise Cancellation Using Vibration Generators on Vehicle Knuckles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing active noise cancellation systems for vehicles are inefficient in reducing road noise due to their reliance on speakers for noise cancellation, which require high-speed arithmetic processing and are costly, and they do not effectively utilize multiple reference signals to reduce vibrations from multiple wheels, leading to incomplete noise reduction.
Innovation Solution
An active noise cancellation apparatus using multiple reference signal detectors on wheel knuckles, a vibration generator on a vehicle component in the vibration transmission path, and an error signal detector to perform adaptive controls and reduce vibrations, thereby effectively reducing road noise by targeting the source of noise generation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If speakers are used for noise cancellation in the vehicle interior, then noise cancellation effect can be achieved, but the system requires high-speed arithmetic processing and incurs high cost
Solution Approach 1:
The patent replaces the acoustic field approach (speakers generating control sound waves) with a mechanical vibration approach (vibration generators directly vibrating the floor panel). This substitution eliminates the need for complex high-speed arithmetic processing required for acoustic noise cancellation, while directly addressing the vibration source of road noise.
Solution Approach 2:
The patent extracts the vibration generation function from the speaker system and implements it separately through dedicated vibration generators mounted on the floor panel. This separation allows independent optimization of the vibration control system without the constraints of acoustic field requirements.
2Object-affected harmful factors
If a single reference signal from one wheel is used, then the system is simple, but road noise cannot be sufficiently reduced since multiple wheels generate vibrations
Solution Approach 1:
The patent merges multiple reference signals from acceleration sensors on different wheels (front left, front right, rear left, rear right) into a unified control signal for the vibration generator. This combination allows the system to address road noise from all wheels simultaneously, achieving sufficient noise reduction while maintaining system manageability.
3Object-affected harmful factors
If the vibration generator is placed on the floor panel, then it can directly reduce floor panel vibration, but the system requires high arithmetic processing speed and incurs high cost
Solution Approach 1:
The patent replaces the complex acoustic control system with a direct mechanical vibration control system. The vibration generator is placed on the floor panel to directly counteract vibrations, eliminating the need for high-speed arithmetic processing associated with acoustic field control while achieving the same noise reduction goal.
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
This solution reliably reduces road noise by using multiple reference signals to control the vibration generator, improving noise cancellation performance while reducing costs and power consumption, and allowing for a more compact design by placing the vibration generator on suspension members or wheel housings rather than floor panels.
Implementation Method 1
a vibration generator placed on a component part in a vibration transmission path from the wheels to the interior and applying vibration force to the component part
Data Source
AI summary
Provided is an active noise cancellation apparatus capable of reliably reducing road noise by reducing vibration of a vehicle component part which generates road noise by using a vibration generator. A plurality of reference signal detectors are placed respectively on right and left knuckles for respectively supporting right and left wheels. A vibration generator and an error signal detector are placed on a vehicle component part. A controller performs respective adaptive controls based on each of reference signals and an error signal so as to reduce the error signal, and controls the vibration generator based on a sum of respective output values of the adaptive controls.