Design and Comparative Analysis of Linear Guides for Refreshable Braille Displays

Author(s):  
Varan Gupta ◽  
Pulkit Sapra ◽  
Suman Muralikrishnan ◽  
M. Balakrishnan ◽  
P. V. M. Rao

Linear guides are extensively employed in several industrial applications. Miniaturization, minimal friction, cost efficiency and low maintenance are the major challenges faced while developing a linear motion system. This paper presents design and realization of such systems, overcoming the aforementioned challenges. Linear guidance mechanisms, suitable for implementing latching in Refreshable Braille Displays are proposed, where uniform behavior under eccentric loading is required. Several low cost, reliable and efficient guide mechanisms with predetermined dimensional constraints have been designed. Seven mechanisms are illustrated and analyzed in this paper, which includes both, traditional contact-based mechanisms and compliant mechanisms that offer contact-less motion. The paper further compares the functionality, cost feasibility and ease of manufacturing and assembly of these mechanisms.


2019 ◽  
Vol 11 (8) ◽  
pp. 168781401987142 ◽  
Author(s):  
Eunho Sung ◽  
Chang-hoon Seo ◽  
Hyunmin Song ◽  
Byungjoo Choi ◽  
Yongho Jeon ◽  
...  

As a method for reducing the friction of high-precision system, air bearings have been widely used for various industrial applications. However, their small damping leads to poor in-position stability and therefore systems are susceptible to residual vibration and disturbance. In this study, a linear motion stage which is guided by air bearing for a noncontact eddy current damping module is proposed. The eddy current damping module consists of a Halbach array of permanent magnets and a fixed conductor plate. An eddy current is generated in the conductor in the direction opposing the change in the magnetic field when the magnets move, after which the resistivity in the conductor dissipates the kinetic energy of the moving part; therefore, the module has a damping effect without contact and system is shown good in-position stability. In order to specify the damping effect, the motion of the moving part was experimentally analyzed. The step response confirmed that the eddy current damping module can improve the performance of the positioning system: the settling time decreased by 36.8% and the resolution improved by 59.4%. These improvements verify that eddy current damping is a suitable method for application in precision industries.





Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1301
Author(s):  
Federico Cavedo ◽  
Parisa Esmaili ◽  
Michele Norgia

A low-cost optical reflectivity sensor is proposed in this paper, able to detect the presence of objects or surface optical properties variations, at a distance of up to 20 m. A collimated laser beam is pulsed at 10 kHz, and a synchronous digital detector coherently measures the back-diffused light collected through a 1-inch biconvex lens. The sensor is a cost-effective solution for punctual measurement of the surface reflection at different distances. To enhance the interference immunity, an algorithm based on a double-side digital baseline restorer is proposed and implemented to accurately detect the amplitude of the reflected light. As results show, the sensor is robust against ambient light and shows a strong sensitivity on a wide reflection range. The capability of the proposed sensor was evaluated experimentally for object detection and recognition, in addition to dedicated measurement systems, like remote encoders or keyphasors, realized far from the object to be measured.



Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2299
Author(s):  
Jéssica P. Silva ◽  
Alonso R. P. Ticona ◽  
Pedro R. V. Hamann ◽  
Betania F. Quirino ◽  
Eliane F. Noronha

Lignocellulosic residues are low-cost abundant feedstocks that can be used for industrial applications. However, their recalcitrance currently makes lignocellulose use limited. In natural environments, microbial communities can completely deconstruct lignocellulose by synergistic action of a set of enzymes and proteins. Microbial degradation of lignin by fungi, important lignin degraders in nature, has been intensively studied. More recently, bacteria have also been described as able to break down lignin, and to have a central role in recycling this plant polymer. Nevertheless, bacterial deconstruction of lignin has not been fully elucidated yet. Direct analysis of environmental samples using metagenomics, metatranscriptomics, and metaproteomics approaches is a powerful strategy to describe/discover enzymes, metabolic pathways, and microorganisms involved in lignin breakdown. Indeed, the use of these complementary techniques leads to a better understanding of the composition, function, and dynamics of microbial communities involved in lignin deconstruction. We focus on omics approaches and their contribution to the discovery of new enzymes and reactions that impact the development of lignin-based bioprocesses.



2021 ◽  
Vol 731 (1) ◽  
pp. 012024
Author(s):  
M N Cahyadi ◽  
E Y Handoko ◽  
R Mardiyanto ◽  
I M Anjasmara ◽  
Khomsin ◽  
...  


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Guhankumar Ponnusamy ◽  
Hajar Farzaneh ◽  
Yongfeng Tong ◽  
Jenny Lawler ◽  
Zhaoyang Liu ◽  
...  

AbstractHeterogeneous catalytic ozonation is an effective approach to degrade refractory organic pollutants in water. However, ozonation catalysts with combined merits of high activity, good reusability and low cost for practical industrial applications are still rare. This study aims to develop an efficient, stable and economic ozonation catalyst for the degradation of Ibuprofen, a pharmaceutical compound frequently detected as a refractory pollutant in treated wastewaters. The novel three-dimensional network-structured catalyst, comprising of δ-MnO2 nanosheets grown on woven carbon microfibers (MnO2 nanosheets/carbon microfiber), was synthesized via a facile hydrothermal approach. Catalytic ozonation performance of Ibuprofen removal in water using the new catalyst proves a significant enhancement, where Ibuprofen removal efficiency of close to 90% was achieved with a catalyst loading of 1% (w/v). In contrast, conventional ozonation was only able to achieve 65% removal efficiency under the same operating condition. The enhanced performance with the new catalyst could be attributed to its significantly increased available surface active sites and improved mass transfer of reaction media, as a result of the special surface and structure properties of this new three-dimensional network-structured catalyst. Moreover, the new catalyst displays excellent stability and reusability for ibuprofen degradation over successive reaction cycles. The facile synthesis method and low-cost materials render the new catalyst high potential for industrial scaling up. With the combined advantages of high efficiency, high stability, and low cost, this study sheds new light for industrial applications of ozonation catalysts.



e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 613-623
Author(s):  
José Manuel Sandoval-Díaz ◽  
Francisco Javier Rivera-Gálvez ◽  
Marta Fernández-García ◽  
Carlos Federico Jasso-Gastinel

AbstractIn this work, for a semicontinuous emulsion polymerization reaction, it is shown that using a redox initiation system at 40°C, substantial modifications in copolymer chain composition with conversion can be easily obtained. To test controllable trajectories for comonomer feeding, linear and parabolic profiles were chosen to get different types of chain composition variations for the 50/50 w/w styrene/n-butyl acrylate system. For the “forced composition copolymers,” the molecular weight averages and distribution were obtained by size exclusion chromatography. The composition along conversion was followed by proton nuclear magnetic resonance to determine the weight composition distribution (WCD) of the copolymer chains. Mechanodynamic (dynamic-mechanical analysis), tensile, and hardness tests exhibited consistent results depending on the WCD that outcomes from the respective feeding profile. The results confirm that this methodology is of great potential for industrial applications when looking for synergy in copolymer properties, and low-cost processes.



Author(s):  
G A Parker ◽  
Y B Sun

The work presented in this paper deals mainly with a mechatronic approach to compact disc valve design and concentrates on improvements to the disc valve electromagnetic characteristics, the diaphragm design and the dynamic performance. A novel diaphragm-disc force motor has been successfully developed incorporating a pair of permanent ring magnets. It has the advantages of low electric power consumption at the null position, dual-lane electrical structure for fail-safe operation, high control accuracy and should be competitive with existing torque motors due to its low cost and simple construction. The research involved designing and testing a prototype disc pilot valve with a dual-lane operating mode. The test results showed that the valve has satisfactory static and dynamic characteristics for industrial applications.



Sign in / Sign up

Export Citation Format

Share Document