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In a daily environment, several vibration energies have low amplitude and broad range of frequencies, and it is crucial to harvest them efficiently in a single triboelectric nanogenerator (TENG). Here, a multi‐degree of freedom (DOF) vibration system is coupled with TENG to make several resonant frequencies in a single device. When the number of DOF increases in the system, the number of resonant frequencies also increases. These resonant frequencies are calculated by MATLAB software using the masses and spring constant of DOF vibration system. With the masses of 20 g and the spring constant of 82.712 N m−1, it is found that 1‐DOF has one resonant frequency (20.47 Hz), 2‐DOF has two resonant frequencies (12.63 and 33.17 Hz), and 3‐DOF has three resonant frequencies (9.12, 25.55, and 36.87 Hz). At each resonant frequency, the displacement of all weight layers increases due to the constructive interference of resonance, resulting in higher output than other frequencies at the frequency sweep experiment. In addition, the magnitude and phase of output signals obtained in friction regions are evaluated through COMSOL simulation. A self‐powered wireless sensor module with 3‐DOF TENGs to detect the humidity/temperature and transmit the data every 30 min by harvesting vibration energy is demonstrated. [ABSTRACT FROM AUTHOR]

With the rapid development of information and communication technology, intelligent wireless systems have a huge demand for devices with multi‐function integration and multi‐degree of freedom electromagnetic control. In this paper, a multifunctional folded transmitarray antenna (MFTA) using a reconfigurable metasurface is proposed to achieve simultaneous and independent modulation of beam and polarization. The beam scanning, arbitrary wave generator, and polarization conversion functions can be achieved only by adjusting the PIN diode bias on the reconfigurable metasurface. In order to prove the feasibility of the proposed method, a prototype is fabricated and verified by experiments. Both simulated and measured results verify the excellent performance of the MFTA. This work opens a door to multi‐functional integration and multi‐degree of freedom electromagnetic manipulate devices, which have great prospects in areas such as radar detection and wireless communication. [ABSTRACT FROM AUTHOR]