Active Vibration Control for Smart Glasses Audio

The patent uses the harmful vibrations generated by speakers and captured by microphones as useful reference signals for active noise control. By treating the vibration-coupled audio as a measurable disturbance rather than merely unwanted noise, the system can generate anti-phase signals to cancel these vibrations, converting the harmful mechanical coupling into a controllable parameter for active vibration reduction.

The patent implements feedback control by continuously monitoring vibrations through microphones and IMUs, processing these signals to determine anti-vibration commands, and applying corrective forces through piezoelectric transducers. This closed-loop feedback mechanism dynamically adjusts the anti-vibration signals based on real-time vibration measurements, effectively reducing the mechanical vibrations generated by speakers.

The patent replaces complex mechanical isolation structures with an active control system using piezoelectric transducers and digital signal processing. Instead of relying on passive mechanical decoupling that would require bulky dampers and isolated mounting structures, the system uses electronically generated anti-vibration signals applied through piezoelectric elements, achieving vibration reduction without increasing mechanical complexity.

The patent changes the approach from passive structural parameter optimization to active control parameter adjustment. By using piezoelectric transducers with adjustable voltage inputs and digital signal processing with adaptive filters, the system can dynamically adjust vibration cancellation parameters without changing the physical structure, thereby reducing device complexity while maintaining effective vibration noise reduction.

The patent applies preliminary anti-action by generating anti-vibration signals before the vibration-distorted audio reaches the microphone. The system proactively counteracts the mechanical vibrations through piezoelectric transducers that apply equal and opposite forces, preventing the vibrations from coupling into the audio path. This preliminary cancellation allows higher amplification gains without introducing feedback or distortion.

The patent introduces piezoelectric transducers as intermediary elements between the speaker-generated vibrations and the microphone. These transducers act as active mediators that convert electrical anti-vibration signals into mechanical counter-forces, isolating the microphone from direct mechanical coupling with the speaker while allowing audio signal transmission, thereby enabling higher stable gain without vibration distortion.