Wearable Smart Silicone Belt for Human Motion Monitoring and Power Generation.

Human physical activity monitoring plays a crucial role in promoting personalized health management. In this work, inspired by an ancient Chinese belt, a belt-type wearable sensor (BWS) based on a triboelectric nanogenerator (TENG) is presented to monitor daily movements and collect the body motion mechanical energy. The developed BWS consists of a soft silicone sheet and systematically connected sensing units made from triboelectric polymer materials including polytetrafluoroethylene (PTFE) and polyamide (PA).

A Wind Bell Inspired Triboelectric Nanogenerator for Extremely Low‑Speed and Omnidirectional Wind Energy Harvesting.

As one of the most promising renewable energies, wind energy is abundant in the natural environment. However, it is still challenging to effectively collect wind energy because of its variable wind speed and unpredictable direction. Here, a triboelectric nanogenerator, which is inspired by ancient Chinese wind bells, has been developed to collect energy from variable-speed and multi-directional wind.

Autonomous Landing of Quadrotor Unmanned Aerial Vehicles Based on Multi-Level Marker and Linear Active Disturbance Reject Control.

Landing on unmanned surface vehicles (USV) autonomously is a critical task for unmanned aerial vehicles (UAV) due to complex environments. To solve this problem, an autonomous landing method is proposed based on a multi-level marker and linear active disturbance rejection control (LADRC) in this study. A specially designed landing board is placed on the USV, and ArUco codes with different scales are employed.

A hybrid energy harvester inspired by bionic flapping wing structure based on magnetic levitation.

A hybrid energy harvester based on magnetic levitation is inspired by the structure of the flapping wing, which consists of two parts: one is a flapping wing structure mounted with a piezoelectric sheet, which can achieve piezoelectric energy harvesting; the other is an intermediate muscle unit, which is vertically arranged by three groups of permanent magnets to achieve magnetic levitation electromagnetic energy harvesting. An electromechanical-electromagnetic coupling model of this harvester is established based on electromechanical coupling characteristics. The simulation analysis can evaluate the magnetic field distribution and nonlinear magnetic properties and also analyze its effects on the output performance.

Design of a multi-direction piezoelectric and electromagnetic hybrid energy harvester used for ocean wave energy harvesting.

Ocean waves contain a great deal of energy, and the collection and utilization of wave energy is of great significance for sustainable development. In this paper, a multi-direction piezoelectric and electromagnetic hybrid energy harvester (PEHEH) based on magnetic coupling is proposed that can collect low frequency vibration energy from multiple directions. The proposed PEHEH combines piezoelectricity and electromagnetism through magnetic coupling to collect energy in the same excitation.

Simulation and Experiment of Active Vibration Control Based on Flexible Piezoelectric MFC Composed of PZT and PI Layer.

In order to improve the vibration suppression effect of the flexible beam system, active control based on soft piezoelectric macro-fiber composites (MFCs) consisting of polyimide (PI) sheet and lead zirconate titanate (PZT) is used to reduce the vibration. The vibration control system is composed of a flexible beam, a sensing piezoelectric MFC plate, and an actuated piezoelectric MFC plate. The dynamic coupling model of the flexible beam system is established according to the theory of structural mechanics and the piezoelectric stress equation.

Fuzzy sliding mode control of piezo-driven stage.

The motion stage with flexible hinges as a guiding mechanism can realize nanometer-level precision positioning. This stage uses a piezoelectric (PZT) actuator as the driving unit. In order to describe the mechanical characteristics of this piezo-driven stage, a double-parallel four-bar mechanism based on eight flexible hinges is analyzed.

Electrochemical Coupled Analysis of a Micro Piezo-Driven Focusing Mechanism.

In order to improve the response speed and output force of the camera focusing mechanism, the authors proposed a novelty micro focusing mechanism based on piezoelectric driving, which has the characteristics of rapid response, high precision positioning and large displacement focusing. In this paper, the operating principle of the proposed focusing mechanism is presented. Using the piezoelectric output characteristic, the movable tooth drive theory and the screw drive theory, the electromechanical coupling mechanical model and equations of the piezoelectric focusing mechanism are established.

A Compound Control Based on the Piezo-Actuated Stage with Bouc-Wen Model.

The piezoelectric actuator (PA) is one of the most commonly used actuators in a micro-positioning stage. But its hysteresis non-linearity can cause error in the piezo-actuated stage. A modified Bouc-Wen model is presented in this paper to describe the hysteresis non-linearity of the piezo-actuated stage.

Nonlinear Vibration of a Micro Piezoelectric Precision Drive System.

A micro piezoelectric precision drive system is proposed, which is advantageous due its small size, large transmission ratio, and large output torque. The working principle of the proposed piezoelectric precision drive system is presented, and the nonlinear dynamic model and equations of the system are established. Using the Linz Ted-Poincaré and perturbation methods, the nonlinear approximate solutions of the dynamic equations are calculated.

Fuzzy adaptive multi-mode sliding mode control for precision linear stage based on floating stator.

This paper outlines a precision motion stage actuated by using a voice coil motor with a floating stator. For getting good performance, a multi-mode sliding mode control (MMSMC) was designed to operate this linear motion stage. MMSMC contains two sliding mode controllers: a sliding-mode control (SMC) and an integral sliding-mode control.

Development of a Contactless Air Conveyor System for Transporting and Positioning Planar Objects.

In this study, we developed a completely contactless air conveyor system for transporting and positioning planar objects. The air conveyor forms a thin film underneath the object for support and simultaneously generates a controlled airflow that results in viscous traction. It is potentially applicable in the manufacturing process for semiconductor wafer or flat foodstuffs, where mechanical contact is expected to be avoided during transportation of the products to minimize contamination.

Hysteresis compensation of the Prandtl-Ishlinskii model for piezoelectric actuators using modified particle swarm optimization with chaotic map.

Piezoelectric actuators invariably exhibit hysteresis nonlinearities that tend to become significant under the open-loop condition and could cause oscillations and errors in nanometer-positioning tasks. Chaotic map modified particle swarm optimization (MPSO) is proposed and implemented to identify the Prandtl-Ishlinskii model for piezoelectric actuators. Hysteresis compensation is attained through application of an inverse Prandtl-Ishlinskii model, in which the parameters are formulated based on the original model with chaotic map MPSO.

Multi-mode sliding mode control for precision linear stage based on fixed or floating stator.

This paper presents the control performance of a linear motion stage driven by Voice Coil Motor (VCM). Unlike the conventional VCM, the stator of this VCM is regulated, which means it can be adjusted as a floating-stator or fixed-stator. A Multi-Mode Sliding Mode Control (MMSMC), including a conventional Sliding Mode Control (SMC) and an Integral Sliding Mode Control (ISMC), is designed to control the linear motion stage.