An upsurge in interest in the area of robust robotic sensors has occurred in recent years, owing to human intervention in dangerous situations, even those potentially leading to death. Here, a mechanically robust boron nitride nanotube (BNNT)-based contact electrification-assisted piezoelectric nanogenerator (BCPENG) was fabricated and tested for its applicability as a robotic sensor with the aid of a triboelectric nanogenerator. High electrical outputs were observed when BNNTs were mixed with carbon nanotubes (CNTs) between the two copper electrode layers of the nanogenerator. The open-circuit voltage of 43.5 V and short-circuit current of 638 nA were generated at the optimized concentrations of 0.5 wt % BNNTs mixed with 0.1 wt % CNTs. Additionally, the energy band diagram and voltage–force relationship are used to analyze the piezoelectric output. This simple operation of the device using a three-dimensional printed finger as an application demonstrates the possibility of successful utilization of this device in kinematic sensors.

A rotating-disk-based triboelectric nanogenerator (TENG) generating electrical energy from wind usually includes a propeller. TENGs are widely used because their high frequency of rotation allows them to generate a relatively high output current. Deep analysis of the gas flow in a TENG is essential to improve its energy conversion efficiency. However, previous studies have isolated the propeller and the TENG as separate entities that harvest wind energy and generate electrical energy, respectively. Most studies focused on each entity because considering both the dynamics and the TENG operation together is an intricate process. This paper introduces a dynamic analysis of the gas flow by dividing it into four vertical and horizontal directions and carrying out a COMSOL simulation to verify the pressure on the propeller and the flow of the gas. The electrical outputs are measured while varying the height and angle of the inlet and the number of wings on the propeller. After optimization, the P-TENG generated a high output power density of 283.95 mW/m 2 , which can light up 205 light-emitting diodes and drive a commercial small electronic appliance. In addition, optimizing the P-TENG through a variety of analyses allowed it to provide sustainable power to a self-powered wireless sensor system.

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With the great development of the Internet of Things (IoT), the use of sensors have increased rapidly because of the importance in the connection between machines and people. A huge number of IoT sensors consume vast amounts of electrical power for stable operation and they are also used for a wide range of applications. Therefore, sensors need to operate independently, sustainably, and wirelessly to improve their capabilities. In this paper, we propose an orientation and the tilt triboelectric sensor (OT-TES) as a self-powered active sensor, which can simultaneously sense the tilting direction and angle by using the two classical principles of triboelectrification and electrostatic induction. The OT-TES device consists of a rectangular acrylic box containing polytetrafluoroethylene (PTFE) balls moved by gravity. The output voltage and current were 2 V and 20 nA, respectively, with a PTFE ball and Al electrode. The multi-channel system was adopted for measuring the degree and direction of tilt by integrating the results of measured electrical signals from the eight electrodes. This OT-TES can be attached on the equipment for drones or divers to measure their stability. As a result, this proposed device is expected to expand the field of TES, as a sensor for sky and the underwater.