scholarly journals Performance Evaluation of a Magnetically Actuated Capsule Microrobotic System for Medical Applications

Micromachines ◽  
2018 ◽  
Vol 9 (12) ◽  
pp. 641 ◽  
Author(s):  
Qiang Fu ◽  
Songyuan Zhang ◽  
Shuxiang Guo ◽  
Jian Guo

The paper aims to propose a magnetic actuated capsule microrobotic system, which is composed of a magnetically actuated microrobot with a screw jet mechanism, a driving system, and a positioning system. The magnetically actuated microrobot embedded an O-ring magnet as an actuator has potential for achieving a particular task, such as medical diagnose or drug delivery. The driving system composes of a three axes Helmholtz coils to generate a rotational magnetic field for controlling the magnetically actuated microrobot to realize the basic motion in pipe, e.g., forward/backward motion and upward/downward motion. The positioning system is used to detect the pose of the magnetically actuated microrobot in pipe. We will discuss the shape of the Helmholtz coils and the magnetic field around the O-ring magnet to obtain an optimal performance of the magnetically actuated microrobot. The experimental result indicated that the microrobot with screw jet motion has a flexible movement in pipe by adjusting the rotational magnetic field plane and the magnetic field changing frequency.

2018 ◽  
Vol 2 (4) ◽  
pp. 68 ◽  
Author(s):  
Emil Chibowski ◽  
Aleksandra Szcześ ◽  
Lucyna Hołysz

Using neodymium ring magnets (0.5–0.65 T), the experiments on the magnetic field (MF) effects on water evaporation rate and surface tension were performed at room temperature (22–24 °C). In accordance with the literature data, the enhanced evaporation rates were observed in the experiments conducted in a period of several days or weeks. However, the evaporated amounts of water (up to 440 mg over 150 min) in particular experiments differed. The evaporated amounts depended partially on which pole of the ring magnet was directed up. The relatively strong MF (0.65 T) caused a slight decrease in surface tension (−2.11 mN/m) which lasted longer than 60 min and the memory effect vanished slowly. The surface tension data reduced by the MF action are reported in the literature, although contrary results can be also found. The observed effects can be explained based on literature data of molecular simulations and the suggestion that MF affects the hydrogen bonds of intra- and inter-clusters of water molecules, possibly even causing breakage some of them. The Lorentz force influence is also considered. These mechanisms are discussed in the paper.


2016 ◽  
Vol 40 (23-24) ◽  
pp. 9835-9847 ◽  
Author(s):  
Ronald Hurtado-Velasco ◽  
Jesus Gonzalez-Llorente

Sensors ◽  
2021 ◽  
Vol 21 (17) ◽  
pp. 5707
Author(s):  
Ching-Han Chen ◽  
Pi-Wei Chen ◽  
Pi-Jhong Chen ◽  
Tzung-Hsin Liu

By collecting the magnetic field information of each spatial point, we can build a magnetic field fingerprint map. When the user is positioning, the magnetic field measured by the sensor is matched with the magnetic field fingerprint map to identify the user’s location. However, since the magnetic field is easily affected by external magnetic fields and magnetic storms, which can lead to “local temporal-spatial variation”, it is difficult to construct a stable and accurate magnetic field fingerprint map for indoor positioning. This research proposes a new magnetic indoor positioning method, which combines a magnetic sensor array composed of three magnetic sensors and a recurrent probabilistic neural network (RPNN) to realize a high-precision indoor positioning system. The magnetic sensor array can detect subtle magnetic anomalies and spatial variations to improve the stability and accuracy of magnetic field fingerprint maps, and the RPNN model is built for recognizing magnetic field fingerprint. We implement an embedded magnetic sensor array positioning system, which is evaluated in an experimental environment. Our method can reduce the noise caused by the spatial-temporal variation of the magnetic field, thus greatly improving the indoor positioning accuracy, reaching an average positioning accuracy of 0.78 m.


1989 ◽  
Vol 169 ◽  
Author(s):  
F. Mizuno ◽  
H. Masuda ◽  
I. Hirabayashi ◽  
S. Tanaka

AbstractFlux pinning and weak link structure were studied on the effect of Ca doping in LnBa2Cu3O7-y system (Ln=La and Y). The magnitude and the magnetic field dependence of the critical current density were improved by Ca doping. A small amount of impurity phase of such as Ca2Cu1O3 may work as a desirable flux pinning center. Moreover, it was found that the current-temperature characteristics for Ca-doped samples showed the evidence of two kinds of superconducting phases which have different transition temperature Tc and Tc'. The experimental result agrees well with the Ambegaokar-Baratoff theory for asymmetric Josephson junctions (S-I-S') in the temperature range of T < Tc' and with the proximity junction theory (S-N-S) in the range of Tc'<T<Tc.


Author(s):  
V.M. Polunin ◽  
◽  
P.A. Ryapolov ◽  
V.G. Bashtovoy ◽  
E.B. Postnikov ◽  
...  

An experimental setup has been developed for studying magnetophoresis in a layer of a magnetic fluid several millimeters thick by the method of transmission and reflection of light. In the experiment, we used the region of a ring magnet changing in sign of the magnetic field. The clarification of the central portion of the magnetic fluid layer, which is observed for several days, is interpreted by the fact that the concentration of particles is redistributed due to the processes of magnetophoresis of microparticles and diffusion of nanoparticles in an inhomogeneous magnetic field.


2018 ◽  
Vol 160 ◽  
pp. 01006 ◽  
Author(s):  
Ivan Zatonov ◽  
Pavel Baranov ◽  
Andrey Kolomeycev

The article considers the calibration system computation with the inhomogeneity of magnetic field less than 0.1 %. Method of calculation is described. The numerical simulation using finite-element analyze was made for such system as: Helmholtz coils, improved Helmholtz coils, four and six coils system. Authors made the calculation of the magnetic field homogeneity toward axial direction. Based on procure results, authors analyzed magnetic field homogeneity and compared different types of coil systems.


2015 ◽  
Vol 10 (1) ◽  
Author(s):  
Fredy Munoz ◽  
Gursel Alici ◽  
Weihua Li

There is an increasing need to incorporate an actively controlled drug delivery system (DDS) into the next generation of capsule endoscopy in order to treat diseases in the gastrointestinal tract in a noninvasive way. Despite a number of attempts to magnetically actuate drug delivery mechanisms embedded in endoscopic capsules, longer operating distances and further miniaturization of on-board components are still drawbacks of such systems. In this paper, we propose an innovative magnetic system that consists of an array of magnets, which activates a DDS, based on an overly miniaturized slider–crank mechanism. We use analytical models to compare the magnetic fields generated by cylindrical and arc-shaped magnets. Our experimental results, which are in agreement with the analytical results, show that an optimally configured array of the magnets enhances the magnetic field and also the driving magnetic torque and subsequently, it imposes a high enough force on the piston of the DDS to expel a required dose of a drug out of a reservoir. We conclude that the proposed magnetic field optimization method is effective in establishing an active DDS that is designed to deliver drug profiles with accurate control of the release rate, release amount, and number of doses.


2019 ◽  
Author(s):  
Yaşar Erdoğan ◽  
Mahir Murat Cengiz

ABSTRACTGeomagnetic field can be used by different magnetoreception mechanisms, for navigation and orientation by honeybees. The present study analyzed the effects of magnetic field on honeybees. This study was carried out in 2017 at the Bayburt University Beekeeping Application Station. In this study, the effect of Electro Magnetic field (EMF) and electric field (EF) on the time of finding the source of food of honeybees and the time of staying there were determined. The honeybees behaviors were analyzed in the presence of external magnetic fields generated by Helmholtz coils equipment. The Electro Magnetic field values of the coils were fixed to 0 μT (90mV/m), 50 μT (118 mV/m), 100 μT (151 mV/m), 150 μT (211 mV/m), 200 μT (264 mV/m). Petri dishes filled with sugar syrup were placed in the center of the coils. According to the study, honeybees visited at most U1 (mean =21.0±17.89 bees) and at least U5 (mean =10.82±11.77 bees). Honeybees waited for the longest time in U1 (mean =35.27±6.97 seconds) and at least in U5 (mean =12.28±5.58 seconds). According to the results obtained from this first study showed that honeybees are highly affected by electromagnetic radiation and electric field.SummaryHoneybees uses the magnetic field of the earth to to determine their direction. Nowadays, the rapid spread of electrical devices and mobile towers leads to an increase in man-made EMF. This causes honeybees to lose their orientation and thus lose their hives.


Sign in / Sign up

Export Citation Format

Share Document