A novel labyrinth seal with staggered helical teeth (SHT) structure is proposed in this paper. The influence of clearance, pressure drop, tooth number and eccentricity on the model studied by numerical simulation. In addition, differences static characteristics between SHT ordinary (OHT) are also compared analyzed. results show that for has better accuracy experimental results. leakage performance than OHT because former can induce higher turbulent energy dissipation at position. Besides,...

To study the lubrication performance of tilting-pad thrust bearing (TPTBs) during start-up in nuclear pump, a hydrodynamic model TPTBs was established based on computational fluid dynamics (CFD) method and fluid-structure interaction (FSI) technique. Further, mesh motion algorithm for transient calculation bearings developed user defined function (UDF). The result demonstrated that minimum film thickness increases first then decreases with rotational speed under condition. influence pad tilt...

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> In vapor compression cycle systems, it is desirable to effectively control the thermodynamic by controlling states of refrigerant. By with an inner loop, supervisory algorithms can manage critical functions and objectives such as maintaining superheat maximizing coefficient performance. practice, generally preferred tune multiple single-input–single-output (SISO) loops rather than a single...

Abstract In this study, the effect of Lode angle on failure and plasticity is considered, a new function developed. Meanwhile, temperature coefficient proposed in model, application model extended to range from room 650°C. The tensile specimens different shapes have been designed calibrate parameters model. tests are carried out situ micro‐tensile machine. For notched at validate constitutive numerical results consistent with experimental ones well, an error 7%. Then, calibrated applied FE...

A novel static model of planetary roller screw mechanisms (PRSMs) is proposed to obtain the load distribution over threads by an energy method. The method consists structural potential and optimization problem. calculated discretization. And problem, whose objective energy, obtained combining principle minimum with forces balance constraints. result finite element established for validation. Compared previous models, has lower complexity higher precision. To further verify reliability...

A reconfigurable modular snake robot has been developed, which can not only move on a plane but aIso achieve some f-dimensional motions while reconfigured. Control equations of 3-dimensional locomotion were established by the composition two bending in mutual orthogonal plane. Three types lateral rolling locomotion, flapping, linear and curved rolling, achieved controlling amplitudes number waves motions. Using three realize net translation, alternation its contact base over obstacles. The...

The mobile robots often perform the dangerous missions such as planetary exploration, reconnaissance, anti-terrorism, rescue, and so on. So it is required that should be able to move in complex unpredictable environment where ground might soft hard, even uneven. To access terrains, a novel robot (NEZA-I) with self-adaptive mechanism proposed developed. It consists of control system unit two symmetric transformable wheel-track (TWT) units. Each TWT driven only by one servo motor, can...

Self-powering mechanisms for synchronized switch harvesting on inductor circuits have been experimentally investigated to harvest low-frequency acoustic energy (∼200 Hz) using multiple lead zirconate titanate piezoelectric plates placed inside a quarter-wavelength straight-tube resonator. Unlike conventional circuits, the self-powered can perform alternating current/direct current conversion without externally powered controllers, which is beneficial in real applications. In harvester,...

A modular universal unit (MUU) is developed for snake-like robots, which has 3 d.o.f. with a series of passive rollers around its cylindrical shell. Among those d.o.f., pitching and yawing are actuated by means differential gears to accomplish large ratio propulsion mass. The the aluminum shell MUU form another wheel that can be used as driving mobile robots. robot composed MUUs more powerful higher mobility. By connecting in different forms, we also realize connected platform or manipulator...

A large class of human movements rely on the so-called hand-eye coordination for precise and versatile performance. Teleoperation agile robotic systems in three dimensional environments would benefit from a detailed understanding perceptual control mechanisms used by operator both design interfaces potentially use gaze information as part mechanism. The objective this work is to model role contribution operator's motion remote operation an vehicle. experiments were conducted using miniature...

Considering that NC machine tools are difficult to be excited, a novel method of executing the self-exciting structural vibration by applying tool movement, which is proved effective testing, presented in proposed study. The influence movement parameters on response studied testing designed under different and comparing characteristics signals time frequency domains. validated comparison frequencies those experimental modal analysis (EMA). As this does not need additional...

Establish a regional cloud account of hospital medical equipment based on dynamic two-dimensional code link.Establish data platform B/S architecture. Combined with mobile internet means such as WeChat and try the industrial 4.0 designed intelligent boxes.The problem no interface transmission integration information is solved. It dynamically collects data, operation cost efficiency. The real-time visualized.The management helps to standardize large improve utilization ratio equipment....

Polymer-derived-ceramic (PDC) route is an excellent strategy to tailor components at the molecular level, while existing synthetic methods face various problems such as complex preparation, multi-step reaction, and high conversion temperature, etc. Here, we propose approach prepare Zr-, Hf-, or Zr/Hf-containing metallocene-based ceramic precursors, which are constructed by alkylation reaction between cyclopentadienyl ligand methylene. Through homogeneous one-pot occurs, collect target...

With the development of mobile internet and intensification differentiated behaviour communication audiences, there are many challenges difficulties in content dissemination to younger generations about promoting Traditional Chinese Medicine (TCM) improving health-related behaviour. Current literature lacks information on association between knowledge, attitude, practice, campus culture construction. This article investigates relationship traditiona medicine construction attitudes, practices...