Article
Multidisciplinary Sciences
Gal Ribak, Roi Gurka
Summary: Waterfowl, such as ducks, use their webbed feet not only for swimming underwater, but also for generating lift and drag. This study investigated the hydrodynamic characteristics of a diving duck's foot and found that drag provided forward thrust during most of the power phase, while lift dominated thrust production at the end of the power stroke. The transfer of momentum from the foot to the water peaked at specific angles of attack.
SCIENTIFIC REPORTS
(2023)
Article
Engineering, Aerospace
Oliver Jia-Richards, Trevor Lafleur
Summary: In this paper, a comprehensive audit of an iodine-based gridded ion thruster is conducted. The thrust estimates from various methods are compared to demonstrate consistency and complete the thrust audit. The results show the agreement of thrust estimates from all four methods and highlight the importance of the study for future mission applications and low-thrust maneuver analysis.
JOURNAL OF PROPULSION AND POWER
(2023)
Article
Instruments & Instrumentation
Asimanshu Das, Matthew Styslinger, Daniel M. Harris, Roberto Zenit
Summary: This letter describes the development of an autonomous swimming robot with a helical tail that operates in a viscous-dominated environment. The flow fields were studied to understand wall effects and hydrodynamic interactions among swimmers. The experimental results were compared with analytical predictions, showing that this robot mimics bacterial swimming strategy and has potential for future applications.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Engineering, Aerospace
Khaled Jarrah, Yazen Alali, Alyssa Lalko, Osamah Rawashdeh
Summary: This paper proposes a novel hybrid multirotor drone design that combines two gasoline engines and four electric motors, significantly extending flight time.
Article
Engineering, Aerospace
Maxime Monette, Matthias Koessling, Martin Tajmar
Summary: This study discusses experiments on propellantless propulsion systems regarding measuring fluctuating mass and using it to generate efficient propellantless thrust. The observed effect is concluded to be the result of coupled vibrations on the torsion balance.
Article
Engineering, Aerospace
Jeongmoo Huh, Ki Sun Park
Summary: This paper investigates the impact of structural materials on the heat loss-related degradation of propulsion performance in micro-scale monopropellant thrusters. A numerical study on conjugate heat transfer is conducted to examine the effect of fabrication materials on heat loss, propellant flow characteristics, and propulsion performance. The results show that thermal diffusivity of the materials leads to different propulsion performance and inner nozzle flow characteristics, particularly in the range of low thermal diffusivity. The materials used for microfabrication affect the degradation of thrust production, with glass exhibiting the least degradation and copper exhibiting the greatest amount of degradation.
Article
Engineering, Aerospace
Ari Rubinsztejn, Carrie Grace Sandel, Rohan Sood, Frank E. Laipert
Summary: This paper explores the use of expected thrust fraction to design resilient trajectories for low-thrust propulsion systems, comparing their performance with traditionally designed trajectories and those with forced terminal coast. Results show that trajectories designed using expected thrust fraction have significantly less arrival delay compared to traditionally designed trajectories, with minimal change in payload mass.
AEROSPACE SCIENCE AND TECHNOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Charlie Pretot, Remi Carmigniani, Loup Hasbroucq, Romain Labbe, Jean-Philippe Boucher, Christophe Clanet
Summary: This article measures the propulsion force of a kayaker using sensors on the paddle and links it to the boat's velocity. A general model for K1 kayak motion is proposed, and three on-water trials are conducted to validate the model and evaluate physics parameters. The results show that the approach can effectively evaluate important parameters for describing a kayak race and monitor athlete performances.
APPLIED SCIENCES-BASEL
(2022)
Article
Remote Sensing
Jiacheng Li, Jie Yang, Haibo Zhang
Summary: Distributed electric propulsion (DEP) aircrafts have the potential for high propulsion efficiency and low fuel consumption, but the redundant thrusters increase the risk of propulsion system faults. In this study, a mathematical model of DEP aircrafts was built and coordinated thrust control and fault-tolerant control methods were designed. Simulation results showed that the controller could control thrust to the prefault level.
Article
Engineering, Electrical & Electronic
Mick Wijnen, Jaume Navarro-Cavalle, Pablo Fajardo
Summary: In this study, a new thrust balance based on Variable Amplitude Hanging Pendulum with Extended Range (VAHPER) concept was developed to measure thrust and specific impulse in electrodeless plasma thrusters. The thrust balance system showed optimized performance characteristics using Lagrangian mechanics and included special features to accommodate the peculiarities of medium power electrodeless plasma thrusters. Testing on a 500-W Helicon Plasma Thruster model showed the system's measured stiffness and thrust range.
IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT
(2021)
Article
Engineering, Marine
Pengcheng Gao, Guanshan Liu, Qiaogao Huang, Dong Song, Guang Pan, Yunlong Ma
Summary: This study investigates the thrust variation, efficiency, and wake evolution of a flapping foil and finds that the addition of perturbations increases the thrust but reduces the propulsion efficiency. Analysis of the wake structure reveals that the changes are closely related to the waveform, base frequency, and perturbation frequency magnitudes of the perturbation signal.
Article
Engineering, Aerospace
Francesco Barato
Summary: In recent years, advancements in commercial hardware technology have made small satellites increasingly important in the Space ecosystem. This paper investigates the optimal alignment of deployable solar panels on satellites in very low Earth orbit, especially when using electric propulsion. The results show that sun-synchronous Dawn-Dusk (or Dusk-Dawn) orbit is preferable for electric propulsion, while small inclinations of the solar panels relative to the velocity vector have a significant impact on drag and power consumption.
Article
Automation & Control Systems
Shengbin Wang, Zheng Chen
Summary: This article presents the design, modeling, and experimental characterization of a two-dimensionally maneuverable jellyfish robot. The robot utilizes a DE membrane to generate periodic contraction on its fins for propulsion and an IPMC for controlling the heading angle. The preliminary results show that the robot can swim effectively underwater in the vertical direction and change its direction by bending the IPMC.
IEEE-ASME TRANSACTIONS ON MECHATRONICS
(2022)
Article
Engineering, Mechanical
Xiaobo Bi, Qiang Zhu
Summary: A novel pulsed-jet propulsive system with a deformable body and affixed nozzle is proposed and studied numerically. The study reveals that the thrust generation is mainly determined by the exit size of the nozzle, with jet flux momentum being the dominant component of thrust.
JOURNAL OF FLUIDS AND STRUCTURES
(2021)
Article
Engineering, Aerospace
Oliver Neunzig, Marcel Weikert, Martin Tajmar
Summary: Propellantless propulsion concepts based on electromagnetic waves, such as the EMDrive, claim to be far superior in spacecraft propulsion systems but lack experimental evidence to support these theories.