Sound collecting device, and method of controlling sound collecting device
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Solution Overview
Problem
Conventional sound collecting devices for vehicles require a position detector to physically detect the rear-view mirror or seat position, leading to increased component complexity and number, making it difficult to obtain high-precision audio while keeping the structure simple.
Innovation Solution
A sound collecting device with a judging unit to determine the current state and a controlling unit that adjusts the microphone array's directionality to focus on the speaking person, eliminating the need for a dedicated position detector by using ambient noise and reflected sound for audio processing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a position detector is used to physically detect the rear-view mirror or seat position, then the position of the speaking person can be detected, but the number of component parts increases and the structure becomes complicated
Solution Approach 1:
The microphone array performs self-position detection by analyzing ambient noise and reflected sound waves. The judging unit determines the speaking person's position based on acoustic signals captured by the microphones themselves, eliminating the need for separate position detectors. This self-service approach resolves the contradiction by maintaining measurement precision while reducing device complexity.
Solution Approach 2:
The microphone array serves dual functions: both audio collection and position detection. By utilizing the same microphones for both sound capture and spatial analysis through ambient noise and reflected sound, the system eliminates the need for dedicated position detection hardware, thereby reducing component count while maintaining detection capability.
2Measurement precision
If the microphone array directionality is always directed toward the speaking person, then audio precision is improved, but the system cannot effectively capture ambient noise or perform position identification
Solution Approach 1:
The microphone array directionality is dynamically adjusted based on the current operational state. The judging unit determines whether the system is in audio collection mode or position identification mode, and the controlling unit accordingly adjusts the beam forming direction. This dynamic adaptability resolves the contradiction by allowing the system to optimize for audio precision when needed while maintaining versatility for other functions.
Solution Approach 2:
The system changes the directional parameters of the microphone array based on operational requirements. By modifying the beam forming control parameters according to the judged state, the system can switch between focused audio capture and omnidirectional ambient noise collection, thereby maintaining both precision and adaptability.
Data Source
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AI summary
An object is to provide a sound collecting device and a method of controlling a sound collecting device with which it is possible to easily obtain audio of a speaking person with a high level of precision while keeping the number of component parts small and preventing the structure from becoming complicated. An audio processing unit 35 judges whether or not the current mode is an operation mode (a speech mode or a conversation mode) in which audio of an occupant of the vehicle serving as a speaking person is obtained (step S1A). When the current mode is another operation mode (an audio playback mode or a head position measuring mode), the audio processing unit 35 sets the directionality of a microphone array to be directed toward the outside of the occupant or to be non-directional (steps S4A and S5A) and obtains input audio of the microphone array. In contrast, when the current mode is an operation mode (the speech mode or the conversation mode) in which audio of the occupant is obtained, the audio processing unit 35 arranges the directionality of the microphone array to be directed toward the occupant (step S2A).