Highly sensitive, source-tracking acoustic sensing is essential for effective and natural human-machine interaction based on voice. It is a known challenge to omnidirectionally track sound sources under a hypersensitive rate with low noise interference using a compact sensor. Here, we present a unibody acoustic metamaterial spherical shell with equidistant defected piezoelectric cavities, referred to as the metasphere beamforming acoustic sensor (MBAS). It demonstrates a wave-confining capability and low self-noise, simultaneously achieving an outstanding intrinsic signal-to-noise ratio (72 dB) and an ultrahigh sensitivity (137 mV _pp /Pa or −26.3 dBV), with a range spanning the daily phonetic frequencies (0 to 1500 Hz) and omnidirectional beamforming for the perception and spatial filtering of sound sources. Moreover, the MBAS-based auditory system is shown for high-performance audio cloning, source localization, and speech recognition in a noisy environment without any signal enhancement, revealing its promising applications in various voice interaction systems.

Incorporating soft actuation with soft yet durable textiles could effectively endow the latter with active and flexible shape morphing and motion like mollusks and plants. However, creating highly programmable and customizable soft robots based on textiles faces a longstanding design and manufacturing challenge. Here, we report a methodology of encoded sewing constraints for efficiently constructing three-dimensional (3D) soft textile robots through a simple 2D sewing process. By encoding heterogeneous stretching properties into three spatial seams of the sewed 3D textile shells, nonlinear inflation of the inner bladder can be guided to follow the predefined spatial shape and actuation sequence, for example, tendril-like shape morphing, tentacle-like sequential manipulation, and bioinspired locomotion only controlled by single pressure source. Such flexible, efficient, scalable, and low-cost design and formation methodology will accelerate the development and iteration of soft robots and also open up more opportunities for safe human-robot interactions, tailored wearable devices, and health care.

This paper reports a novel mode-localized resonant accelerometer, which can keep high sensitivity even over a wide range. To improve the adjustability of sensitivity, a new four degree of freedom (4-DoF) series-parallel resonator array is proposed. Three sensing resonators are mechanically coupled together in series by folding beams and the fourth sensitivity-tuning resonator is electrically coupled in parallel with the sensing system. When the stiffness perturbation caused by acceleration occurs, a change of modal amplitude ratio due to the mode localization phenomenon can be detected. By tuning the voltage on the sensitivity-tuning resonator, the sensitivity of the accelerometer can be altered to keep the amplitude ratio within a reasonable range. The theoretical model of the accelerometer is established and analyzed by numerical method. To confirm the feasibility of the design, a device fabricated by SOI-MEMS technology is tested under open-loop circuit. The measured amplitude ratio sensitivity varies from 1.14/g to 23.37/g with the change of the tuning voltage, and the sensitivity adjustment range reaches 2050%. [2019-0199]