Results 141 to 150 of about 284,887 (285)

Analysis of Drill String Coupled Vibration and Drilling Fluid Pressure in Downhole Section

Shiyou jixie, 2021
To address the problem of nonlinear coupled vibration of the drill string in the axial, lateral and torsional direction in the downhole section of deepwater drilling, a mathematical model of nonlinear coupled vibration of the drill string in the downhole
Liu Jing, Wang Chuan, Hao Chen, Du Qingyun, Wang Tao, Zhang Cheng   +5 more
doaj  

Development of Heat Engines Powered by Twisted and Coiled Polymer Fiber Actuators

Advanced Materials Technologies, EarlyView.
Continuously rotating engines driven by thermally responsive actuating materials can turn waste heat into useful energy. For the first time heat engines operated by twisted and coiled polymer fiber actuators are demonstrated with engine design guided by two simple analytical models.
Geoffrey M. Spinks, Burhan Bin Asghar Abbasi, Zhen Jiang   +2 more
wiley   +1 more source

A Proof‐of‐Concept Assessment of a Novel Wearable Eyelid Muscle Device: A Pre‐Clinical Animal Cadaver Study for Eyelid Closure Restoration

Advanced Robotics Research, EarlyView.
This article introduces a soft wearable eyelid sling device incorporating a hydraulic soft artificial muscle (SAM) for achieving complete closure of an eyelid. The SAM is driven by a cam mechanism that provides a displacement profile closely matched with those of a healthy eyelid.
Patrick Pruscino, Phuoc Thien Phan, James Davies, Bibhu Sharma, Tianruo Guo, Chi Cong Nguyen, Nigel H. Lovell, Thanh Nho Do   +7 more
wiley   +1 more source

Multi‐Material Additive Manufacturing of Soft Robotic Systems: A Comprehensive Review

Advanced Robotics Research, EarlyView.
This review explores the transformative role of multi‐material additive manufacturing (MMAM) in the development of soft robotic systems. It presents current techniques, materials, and design strategies that enable functionally graded and adaptive structures.
Ritik Raj, Quan‐Chen Song, Jia‐Yang Juang   +2 more
wiley   +1 more source

Null Energy Condition Violation and Classical Stability in the Bianchi I Metric

, 2009
The stability of isotropic cosmological solutions in the Bianchi I model is considered. We prove that the stability of isotropic solutions in the Bianchi I metric for a positive Hubble parameter follows from their stability in the Friedmann-Robertson ...
A. A. Starobinsky, A. A. Starobinsky, A. M. Lyapunov, A. M. Lyapunov, D. J. Mulryne, D. M. Grobman, G. F. R. Ellis, I. Ya. Aref’eva, I. G. Petrovsky, I. Ya. Aref’eva, I. Ya. Aref’eva, L. V. Joukovskaya, L. S. Pontryagin, N. V. Bulatov, P. Hartman, P. Hartman, S. Yu. Vernov, S. W. Hawking, S. Yu. Vernov   +18 more
core   +1 more source

TreeSpider: In‐Canopy Exploration With Tether‐Based Aerial Modular Arms

Advanced Robotics Research, EarlyView.
A tethered drone with perching arms and a 360° ring enables unprecedented maneuverability within dense forest canopies. By dynamically adjusting tether length and decoupling pitch from the frame, it navigates between branches, senses multiple trees, and interacts physically with foliage.
Luca Romanello, Tian Lan, Salaheldin Hassan, Maximilian Leutschafft, Erdem Ekinci, Sophie F. Armanini, Mirko Kovac, Basaran Bahadir Kocer   +7 more
wiley   +1 more source

Nonsingular Terminal Sliding Mode Control for Vehicular Platoon Systems with Measurement Delays and Noise

Computation
Platooning of vehicular systems has been considered an effective solution for alleviating traffic congestion and reducing energy consumption. Because of limitations in onboard sensors, the measurement system inevitably suffers from measurement delays and
Mengjie Li, Shaobao Li, Xiaoyuan Luo, Zhizhong Bai   +3 more
doaj   +1 more source

Enabling Real‐Time Shape‐Sensing in Soft Robots via a Miniaturized, Single‐Signal, Color‐Tuned Soft Optical Sensor

Advanced Robotics Research, EarlyView.
A miniaturized soft optical sensor that uses thin film color tuning enables real‐time 3D shape‐sensing from a single red–green–blue (RGB) signal. When integrated into a soft robot, it enables closed‐loop control and autonomous navigation in a phantom lung environment without the need for onboard electronics, achieving sub‐millimeter accuracy through ...
Frank Juliá Wise, Yitong Lu, Daniel Van Lewen, Riley Applebaum, Bianca Andrada, Johnathan Reamer, Sheila Russo   +6 more
wiley   +1 more source

Mechanical Stability of Cylindrical Thin-Shell Wormholes

, 2013
In this paper, we apply the cut and paste procedure to charged black string for the construction of thin-shell wormhole. We consider the Darmois-Israel formalism to determine the surface stresses of the shell.
Azam, M., Sharif, M.
core   +1 more source

Nanomaterial‐Based Muscle Cell/Neural Tissue Biohybrid Robots: From Actuation to Biomedical Applications

Advanced Robotics Research, EarlyView.
Muscle cell‐based biohybrid robot using nanomaterials for function enhancement and neural function for biomedical applications. Biohybrid robotics, an emerging field combining biological tissues with artificial systems, has made significant progress in developing various biohybrid constructs, including muscle‐cell‐driven biorobots and microbots.
Minkyu Shin, Sangeun Lee, Su Ryon Shin, Jin‐Ha Choi, Jeong‐Woo Choi   +4 more
wiley   +1 more source