Soft actuators that exhibit large deformation and can move at a fast speed in response to external stimuli have been high demand for biomimetic applications. In this paper, we propose convenient approach fabricate reversible thermal-responsive composite hydrogel. Under the irradiation of visible light, striped hydrogel bend up 65.72°/s with carbon nanotubes loaded concentration 3 mg/mL. A jellyfish-like miniature soft robot is made using When driven by maximum 3.37 mm/s. Besides swimming,...

The YOLOv4 neural network is employed for underwater target recognition. To improve the accuracy and speed of recognition, structure modified by replacing upsampling module with a deconvolution incorporating depthwise separable convolution into network. Moreover, training set used in YOLO preprocessed using mosaic augmentation, which gray world algorithm to derive two images when performing augmentation. recognition results comparison other detectors demonstrate effectiveness proposed method...

Human-machine interface(HMI) technology has gradually become a research hotspot with the continuous development of computer and Internet Things (IOT) technology. Hand gesture recognition (HGR) as an important part HMI been widely concerned. Among many technical routes HGR technology, wearable based on A-mode ultrasound shows great application potential due to its advantages such lightweight device, free from sensors' constraint etc. However, in process processing ultrasonic signal, amplitude...

At present, the research on gesture recognition based ultrasonic signals is mostly about static gestures. Compared with gestures, dynamic gestures reflect human intent more intuitively. However, speed difference of will cause a mismatch in time series. To tackle this problem, we proposed scheme warping (DTW) algorithm. First, forearm muscles were acquired by four A-mode transducers. Second, original underwent Gaussian filtering, feature extraction, normalization, and principal component...

A model of a submerged angular cavitation nozzle is established, which consists contraction part, parallel middle and expansion part. Based on the CFD technique, numerical simulation flow field carried out, in multiphase mixture model, renormalization group (RNG) k-ε turbulence are applied. Considering influence density cavitation, effects inlet outlet part velocity vapor volume fraction studied. The results show that essential jet. When diameter d fixed, designed with angle α = 13.5°,...

In response to the new requirements for face gear transmissions in latest heavy-load helicopters, this paper investigates impact of pressure angle variations on geometric contact and performance asymmetric gears. Firstly, using meshing theory, tooth surface equations rack cutter, shaper, are derived, parameterized 3D models created. Secondly, line action (LOA), ratio, point curvature, load sharing ratio considering multi-pair (MPC) under different angles analyzed. Then, a wear calculation...

The wires and ground on transmission towers cannot be straight lines, but present different sizes of arcs, which directly affect the safety quality line. In response to this, a research proposes an online monitoring system for based computer video algorithms. collects environment mechanism parameters lines by installing sensors towers, monitors them through algorithms, combines grey wolf algorithm deep learning models predict sag, thereby achieving crisis warning power grid around towers....

Abstract Toroidal drives combine a planetary gear drive with worm drive. Furthermore, in toroidal drives, the teeth are movable. The motion of spherical movable for gears affects friction, wear and transmission efficiency meshing surface, but this effect has not been thoroughly studied to date. This study involved kinematic analysis teeth. Frenet-fram was first introduced into describe A contact carried out, mathematical model rolling–sliding between central spiral groove established via...

Abstract In the past two decades, micro/nanomotor is emerging as a critical domain of nanoscale research. Light-driven micro/nanomotors have gained wealth attention from academics because their potential applications in various fields such environment remediation, biomedical field and cargo delivery at microscale. order to perform some more challenging complex tasks, higher actuation force precise control are both indispensable for light-driven micro/nanomotors. this review, we discussed...

A-mode ultrasound has the advantages of high resolution, easy calculation and low cost in predicting dexterous gestures. In order to accelerate popularization gesture recognition technology, we designed a human-machine interface that can interact with user real-time. Data processing includes Gaussian filtering, feature extraction PCA dimensionality reduction. The NB, LDA SVM algorithms were selected train machine learning models. whole process was written C++ classify gestures This paper...

The purpose of this paper is to propose a pair external and internal spiral bevel gears with double circular-arc in the nutation drive. Based on movement nutation, develops equations tooth profiles for gear set, leading mathematical modeling constant helical angle alignment curve, enabling surface be generated, permitting theoretical contacting lines produced light meshing function. Simulation verification are carried out prove equations. Numerical control (NC) simulation machining...

Terahertz time-domain spectroscopy is a contactless and nondestructive testing technique that often used to measure the thickness of layered materials. However, presents limited detection resolution, especially in thin thermally grown oxide (TGO) thermal barrier coatings whose below 30 µm. In this study, an SWT-BP algorithm combining stationary wavelet transform (SWT) backpropagation (BP) neural network was proposed, regression coefficient SWT-detailed results 0.92. The prediction were good...