scholarly journals Research on reliable sealing technology of spacecraft rectangular hatch based on boundary control

2021 ◽  
Vol 2085 (1) ◽  
pp. 012019
Author(s):  
Yan Wang ◽  
Yun Li ◽  
Yuan Zhuang ◽  
Benhua Zhao ◽  
Huaxing Ren ◽  
...  
Keyword(s):  
Boundary Control ◽  
Large Diameter ◽  
Degree Of Freedom ◽  
Linkage Mechanism ◽  
Door Opening ◽  
Large Size ◽  
Compression Mechanism ◽  
Long Life ◽  
Opening And Closing ◽  
Multiple Compression

Abstract In view of the large size of the sealing surface of the space large diameter rectangular cabin door, the large number of locking mechanisms and long service life, it is difficult to adjust the multi degree of freedom attitude in the assembly process, the complex assembly and adjustment of the mechanism, the synchronization accuracy is not easy to ensure, the consistency of the multi-point seal compression rate is high, and it is not easy to control. Based on the rotation law of the spatial linkage mechanism, the precise dimension chain control of the hatch is carried out, and the attitude of the multi degree of freedom linkage is adjusted to realize the synchronous compression of multiple compression units of the compression mechanism; Based on the minimum and maximum operating force as the boundary, through the sealing stress simulation, the “boundary control” coupling assembly and adjustment technology is proposed to optimize the sealing structure and realize rapid and efficient assembly. The results show that the vacuum leakage rate is still less than 2.5×10−3 PaL/s after 2000 door opening and closing tests and sealing compression ratio are better than 15%. The long-life test verifies the feasibility and effectiveness of this method, and forms a set of high reliable and long-life sealing assembly and adjustment method of space hatch, which provides technical guidance and reference for the subsequent assembly of similar space hatch mechanisms.

Design Optimization of RML Glove for Improved Grasp Performance

2018 ◽  
Author(s):  
Teja Vanteddu ◽  
Bijo Sebastian ◽  
Pinhas Ben-Tzvi
Keyword(s):  
Design Optimization ◽  
Daily Living ◽  
Experimental Validation ◽  
Large Diameter ◽  
Future Research ◽  
Linkage Mechanism ◽  
Design Variables ◽  
Wide Range ◽  
Optimal Values ◽  
Optimal Set

This paper describes the design optimization of the RML Glove in order to improve its grasp performance. The existing design is limited to grasping objects of large diameter (> 110mm) due to its inability in attaining high bending angles. For an exoskeleton glove to be effective in its use as an assistive and rehabilitation device for Activities of Daily Living (ADL), it should be able to interact with objects over a wide range of sizes. Motivated by these limitations, the kinematics of the existing linkage mechanism was analyzed in detail and the design variables were identified. Two different cost functions were formulated and compared in their ability to yield optimal values for the design variables. The optimal set of design variables was chosen based on the grasp angles achieved and the resulting mechanism was simulated in CAD for feasibility testing. An exoskeleton mechanism corresponding to the index finger was manufactured with the chosen design variables and detailed experimental validation was performed to illustrate the improvement in grasp performance over the existing design. The paper ends with a summary of the experimental results and directions for future research.

Design of a Teaching Robot with Three Degrees of Freedom

2012 ◽  
Vol 619 ◽  
pp. 325-328
Author(s):  
You Jun Huang ◽  
Ze Lun Li ◽  
Zhi Cheng Huang
Keyword(s):  
Degrees Of Freedom ◽  
Low Cost ◽  
Degree Of Freedom ◽  
Good Repeatability ◽  
Main Components ◽  
Opening And Closing ◽  
Three Degree Of Freedom ◽  
Three Degrees Of Freedom ◽  
Application Prospects

A teaching robot with three degree of freedom is designed. The three degrees of freedom are: waist rotation, lifting and stretching of the arm and opening and closing of the gripper. The designs of the main components are: a mobile chassis, parallel rails, horizontal rails and manipulator. The teaching robot designed has the features of low cost, easy to regulation, good repeatability and it has good promotion and application prospects in the field of teaching.

scholarly journals Sistem Pintu Otomatis Menggunakan E-KTP Berbasis Internet of Things (IoT) pada Kamar Hotel

2021 ◽  
Vol 1 (2) ◽  
pp. 85-91
Author(s):  
Yulisman ◽  
Naziful Iman ◽  
Eka Sabna ◽  
Hendry Fonda
Keyword(s):  
Research Method ◽  
Prototype Model ◽  
Card Reader ◽  
Hotel Room ◽  
Door Opening ◽  
A Value ◽  
Door Lock ◽  
Hotel Security ◽  
Opening And Closing ◽  
Internet Of Thing

The system of opening and closing the hotel room doors is already using RFID but its use is still not optimal because the card used is very expensive and the card used can only be one card for each room, so if the card is lost, you have to re-enter the card id. Therefore, digital electronic technology systems and devices are needed to make it easier to open the door and close the hotel room so that it can facilitate the hotel security system with automatic locks. This system and device uses an E-KTP and an Internet of Thing (IoT)-based Keypad and which functions to control the device using a NodeMCU while for a card reader with an RFID engine. The research method uses a model, namely with a prototype model for making systems and automatic room door locking system tools. The results and conclusions of the manufacture of hotel room automatic door locking systems and devices using an Internet of Thing (IoT)-based E-KTP equipped with a message LCD and keypad as a door opening solution if the RFID machine does not work. The security of hotel guests who stay is more guaranteed and can also make it easier for guests and hotel staff with an automatic hotel room door lock system. The results of the user's assessment of the work of a series of systems and tools to open and lock this automatic hotel room door are very good with a value of 88.7%.

scholarly journals DEVELOPMENT OF A NEW DESIGN METHODOLOGY FOR LARGE SIZE PRODUCTS BASED ON DSM AND DFMA

2020 ◽  
Vol 1 ◽  
pp. 2315-2324
Author(s):  
B. Mora ◽  
I. Retolaza ◽  
M. A. Campos ◽  
A. Remirez ◽  
M. J. Cabello ◽  
...  
Keyword(s):  
Conceptual Design ◽  
Design Methodology ◽  
Design For Manufacturing ◽  
Design Structure Matrix ◽  
Structure Matrix ◽  
Large Size ◽  
Design Structure ◽  
Long Life

AbstractA new design methodology for long life and large size (Ll-Ls) products called Design for Installation (DfI) is proposed. Ll-Ls products are usually made up of large parts that need to be assembled on field. The proposed methodology, based on adapted Design Structure Matrix (DSM) and Design for Manufacturing and Assembly (DfMA) methods, enables to optimize the design of a Ll-Ls product in order to reduce time and cost of the installation process. The new methodology works with a conceptual design of the product and the weight and size restrictions given by logistic factors as inputs.

Energy Saving Method for Operating CNC Machine Door

2017 ◽  
Vol 867 ◽  
pp. 272-279
Author(s):  
N. Gayathri ◽  
V.K. Shanmuganathan ◽  
K.G. Karthigayan ◽  
S. Manesh Kumar
Keyword(s):  
Energy Saving ◽  
Electric Energy ◽  
Energy Crisis ◽  
Single System ◽  
Cnc Machine ◽  
Door Opening ◽  
Different Types ◽  
Energy Consuming ◽  
Save Energy ◽  
Opening And Closing

Energy is an important aspect in our day to day life. It is important to save energy wherever possible that to electric energy. We are suffering from electric energy crisis now-a-days. In order to save electric energy alternate system is chosen and it is implemented which would save electric energy. Wasting energy for supplementary or supporting works like machine door opening and closing considered as uneconomical. Energy consuming system consumes lot of energy for supporting works. In this energy saving concept two different types of system can be coupled to work as a single system which would save much energy than before. Our concept discusses about the same. Energy wastage for operating CNC machine door is taken for consideration in our work and analysis has been done on it. A new hydraulic operating system is proposed to overcome the difficulties.

scholarly journals Demonstration of the Use of Remote Temperature Monitoring Devices in Vaccine Refrigerators in Haiti

2017 ◽  
Vol 133 (1) ◽  
pp. 39-44 ◽  
Author(s):  
Kathleen F. Cavallaro ◽  
Jeannot Francois ◽  
Roody Jacques ◽  
Derline Mentor ◽  
Idrissa Yalcouye ◽  
...  
Keyword(s):  
Heat Exposure ◽  
Temperature Monitoring ◽  
Cold Chain ◽  
Solar Panels ◽  
Door Opening ◽  
Start Up ◽  
Data Gaps ◽  
Opening And Closing ◽  
Monitoring Devices ◽  
Routine Immunization Schedule

After the 2010 earthquake, Haiti committed to introducing 4 new antigens into its routine immunization schedule, which required improving its cold chain (ie, temperature-controlled supply chain) and increasing vaccine storage capacity by installing new refrigerators. We tested the feasibility of using remote temperature monitoring devices (RTMDs) in Haiti in a sample of vaccine refrigerators fueled by solar panels, propane gas, or electricity. We analyzed data from 16 RTMDs monitoring 24 refrigerators in 15 sites from March through August 2014. Although 5 of the 16 RTMDs exhibited intermittent data gaps, we identified typical temperature patterns consistent with refrigerator door opening and closing, propane depletion, thermostat insufficiency, and overstocking. Actual start-up, annual maintenance, and annual electricity costs for using RTMDs were $686, $179, and $9 per refrigerator, respectively. In Haiti, RTMD use was feasible. RTMDs could be prioritized for use with existing refrigerators with high volumes of vaccines and new refrigerators to certify their functionality before use. Vaccine vial monitors could provide additional useful information about cumulative heat exposure and possible vaccine denaturation.

The biology of Gammarus (Crustacea, Amphipoda) in the northwestern Atlantic. V. Gammarus oceanicus Segerstråle

1972 ◽  
Vol 50 (6) ◽  
pp. 801-813 ◽  
Author(s):  
V. J. Steele ◽  
D. H. Steele
Keyword(s):  
Body Length ◽  
Long Island ◽  
Reproductive Potential ◽  
Long Island Sound ◽  
Size At Maturity ◽  
Foxe Basin ◽  
Large Size ◽  
Mean Size ◽  
Long Life ◽  
Island Sound

Gammarus oceanicus is an intertidal species found between Long Island Sound and southern Foxe Basin in the northwestern Atlantic. Fifty percent maturity of the females is attained at 11 and 13.8 mm body length in the January–May and June–August periods, respectively, at Holyrood, Nfld., and at 11.4 and 13.7 mm at St. Andrews, N.B. In the laboratory females matured in the 13th molt at a mean size of 12 mm in an average of 329 and 230 days at 3 and 12 °C, respectively. Females produce successive broods except between August and November when they enter the resting stage. Relatively few young are released in the winter months. Fecundity increases with the size of the female and the large size at maturity, continued growth, and long life give this species a high reproductive potential.

Long-life Na-rich nickel hexacyanoferrate capable of working under stringent conditions

2021 ◽  
Vol 9 (37) ◽  
pp. 21228-21240
Author(s):  
Yunpo Sun ◽  
Yunli Xu ◽  
Zheng Xu ◽  
Yu Sun ◽  
Xiongwen Xu ◽  
...  
Keyword(s):  
Cycle Life ◽  
Nickel Hexacyanoferrate ◽  
Large Size ◽  
Rate Capacity ◽  
Long Life

Na-rich, large-size NiHCF exhibits an ultralong cycle life and excellent rate capacity, and is capable of working under stringent conditions.

scholarly journals Morphology of Anemone sylvestris L. flower (Ranunculaceae)

2016 ◽  
Vol 75 (1) ◽  
pp. 74-80 ◽  
Author(s):  
Bożena Denisow ◽  
Sebastian Antoń ◽  
Małgorzata Wrzesień
Keyword(s):  
Seed Set ◽  
Pollen Dispersal ◽  
Pollen Grains ◽  
Starch Accumulation ◽  
Pollination Syndrome ◽  
Wind Pollination ◽  
Intermediate Form ◽  
Protected Species ◽  
Large Size ◽  
Opening And Closing

Abstract During the monitoring of populations of Anemone sylvestris L. (Ranunculaceae), a protected species in Poland, we found that the seed set is impaired. The flower is considered an adaptation that has coevolved to achieve effective pollination and successful fertilization. Therefore we have focused on the morphological and anatomical characteristics of the flowers of A. sylvestris L. as a prelude to the study of the species’ pollination biology and plant breeding system. The large size of the flower (50.6 ± 16.4 mm in dimensions) and its bowl shape fulfil both the biotic pollination syndrome and the aerodynamic requirements for pollen dispersal and capture. The opening and closing of the perianth provide a shelter for beetles. The odourless perianth, absence of nectar, scarcity of pollen (approximately 200 000 pollen grains per flower) and its traits - small size (axis P = 18.52 ± 1.0 μm; E = 16.59 ± 0.9 μm), lack of balsam on the exine surface, starch accumulation in more than 95% of pollen grains correspond to the specialization in anemophily. The stigma is papillous, the dense hairs are situated between single carpels indicating adaptation to capturing dry pollen and specialization in the wind pollination syndrome. The flower of A. sylvestris is an example for an intermediate form between entomophily and anemophily, i.e. a secondary and more advanced feature among Ranunculaceae.

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