Active headrest device based on infrared positioning

Abstract

The invention discloses an active headrest device based on infrared positioning. The device comprises a secondary sound source, a reference microphone and a control system. The device also comprises at least three infrared range finders and a positioning system. The controller comprises an optimal control coefficient database. The positioning system determines the position of the head of a personin an activity region according to distance information provided by the infrared range finders, sends the position to the control system, and acquires an optimal controller coefficient from the optimal control coefficient database according to the position of the head of the person. According to coefficient, references signals acquired by the reference microphone are filtered and then sent to thesecondary sound source, so the secondary sound source is allowed to give out sound, thereby achieving noise control. According to the invention, by acquiring a control target position, a pre-designedoptimal controller coefficient is selected in the current position, so it is ensured that when the head of the person is moving, stable and consistent noise control effects can be acquired.

Description

technical field [0001] The invention relates to the field of active noise control, in particular to an active headrest device based on infrared positioning. Background technique [0002] In the field of traditional noise control, sound insulation and sound absorption materials are usually used to reduce the noise in the space. This method has a good control effect on high-frequency noise, but if the same control effect is also required on low-frequency noise, a larger volume is required. , weight, such a method increases the cost and is not practical in actual situations. Therefore, for low-frequency noise, the method of active noise control is usually used to reduce low-frequency noise, that is, the speaker emits reverse sound waves to offset the original noise at the current position to achieve noise reduction. These speakers are called secondary sound sources. Active noise control is also called "active noise control" (Active noise control, ANC) in some literatures. [...

AI Technical Summary

Problems solved by technology

[0005] U.S. Patent No. 8,325,934 and U.S. Patent No. 9,640,167, etc. have all mentioned the method of using the method of active headrest system to control the noise at the ears of the head in the prone position, but considering that in the real environment, the position of the head will change. , the position of the human ears (target point) will change, and the secondary pathway will also change accordingly. At this time, the control effect of the system will decrease

The University of Southampton in the UK proposed to use some commercial kits for VR systems to accurately locate the head position, but the system volume and space occupied are large, the cost is high, and the system complexity increases accordingly.

[0006] To sum up, the current active headrest system using active noise control has a general control effect when the position of the head changes, while the use of third-party commercial software makes the system larger and less flexible

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