Application of Alternative Support Fixture System in Vibration Suppression of Thin-Walled Parts

Author(s):  
Ze Liu ◽  
Yu Sun ◽  
Yu Wang

Abstract The machining vibration of thin-walled parts affects the quality of the products. Thus, this paper proposes a new alternative support fixture system for vibration suppression of thin-walled parts. The system includes two movable supporting heads, which are periodically repositioned along the machining path in the form of alternating support to support the area close to the cutter, so as to improve the rigidity of the actual machining position of the thin-walled part. Around this new system, a dynamic model is established to analyze the workpiece vibration. Takeing as an example simply suppoted thin-plate, the influence of the supporting head’s location, stiffness coefficient and damping coefficient on vibration suppression are numerically analyzed in this paper. The result of the simulation demonstrates the alternative support fixture system is effective in vibration suppression of thin-walled parts.

2019 ◽  
Vol 214 ◽  
pp. 05001 ◽  
Author(s):  
Stefan-Gabriel Chitic ◽  
Ben Couturier ◽  
Marco Clemencic ◽  
Joel Closier

A continuous integration system is crucial to maintain the quality of the 6 millions lines of C++ and Python source code of the LHCb software in order to ensure consistent builds of the software as well as to run the unit and integration tests. Jenkins automation server is used for this purpose. It builds and tests around 100 configurations and produces in the order of 1500 built artifacts per day which are installed on the CVMFS file system or potentially on the developers’ machines. Faced with a large and growing number of configurations built every day, and in order to ease inter-operation between the continuous integration system and the developers, we decided to put in place a flexible messaging system. As soon as the built artifacts have been produced, the distributed system allows their deployment based on the priority of the configurations. We will describe the architecture of the new system, which is based on RabbitMQ messaging system (and the pika Python client library), and uses priority queues to start the LHCb software integration tests and to drive the installation of the nightly builds on the CVMFS file system. We will also show how the introduction of an event based system can help with the communication of results to developers.


2010 ◽  
Vol 97-101 ◽  
pp. 1841-1844
Author(s):  
Shi Huan Wang ◽  
Zhi Gang Cai ◽  
Li Fang Lin

Surface machining system based on spherical coordinate is present for the large thin-walled director sphere part turning, to improve the efficiency and quality of part machining. In this system, a thickness surface B-spline model is set up based on spherical coordinates, the space spiral path generation method is planned, row spacing angle is determined by scallop height and blunt radius of cutting tool, and back cutting depth optimization treatment and space spiral interpolation algorithm are present.


2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
A. B. Usakli ◽  
S. Gurkan ◽  
F. Aloise ◽  
G. Vecchiato ◽  
F. Babiloni

The aim of this study is to present electrooculogram signals that can be used for human computer interface efficiently. Establishing an efficient alternative channel for communication without overt speech and hand movements is important to increase the quality of life for patients suffering from Amyotrophic Lateral Sclerosis or other illnesses that prevent correct limb and facial muscular responses. We have made several experiments to compare the P300-based BCI speller and EOG-based new system. A five-letter word can be written on average in 25 seconds and in 105 seconds with the EEG-based device. Giving message such as “clean-up” could be performed in 3 seconds with the new system. The new system is more efficient than P300-based BCI system in terms of accuracy, speed, applicability, and cost efficiency. Using EOG signals, it is possible to improve the communication abilities of those patients who can move their eyes.


2016 ◽  
Vol 24 (4) ◽  
pp. 797-807 ◽  
Author(s):  
Saikat Dutta ◽  
Seung-Bok Choi

Vehicle stability largely depends on the vibration of the steering system. A four degrees of freedom dynamic model of an automotive steering system with a magneto-rheological damper is presented in this study. Firstly, an equivalent mathematical model of the steering system is developed. The nonlinear equation of motion obtained from the dynamic model is then linearized around its equilibrium point to make it suitable for the design of an appropriate controller for vibration suppression. In this work, a new type of adaptive sliding mode controller is designed for control of the magneto-rheological damper and hence to control unwanted vibration. It is shown that the proposed control logic is very effective for settling steering motion near the equilibrium position. The shimmy vibrations of the wheels are reduced by a considerable amount and the steering system becomes stable. In addition, a comparative work is undertaken between the proposed controller and an ordinary sliding mode controller to demonstrate the advantage of the proposed methodology.


KOMTEKINFO ◽  
2020 ◽  
Vol 7 (2) ◽  
pp. 171-175
Author(s):  
Rima Liana Gema ◽  
Mutiana Pratiwi ◽  
Shary Lusinia ◽  
Devia Kartika ◽  
Ulya Ilhami Arsyah

The use of computers in people's lives is growing as is the case with companies that provide scholarships for the children of employees who work at the company. The scholarship selection system is still done manually so it is ineffective and inefficient and requires a long time. By using a new system design to assist in data processing of spare part goods, producing a desired system a system is created. In this study the authors used the method of field research, interviews, library research and laboratory research, in conducting analysis using UML (Unified Model Language). The new system will be implemented later to improve the quality of information generated so that these designs can be useful for the company concerned.


2019 ◽  
Vol 10 (11) ◽  
pp. 1131-1135
Author(s):  
Tomas Hambili Paulo Sanjuluca ◽  
◽  
Ricardo Correia ◽  
Anabela Antunes de Almeida ◽  
Ana Gloria Diaz Martinez ◽  
...  

Introduction: In order to have a good assessment of the quality of maternal and child health care, it is essential that there is up-to-date and reliable information. Objective: To evaluate the impact of the implementation of a computerized database of clinical processes in the admission, archive and medical statistics section, of Maternity hospital Irene Neto/Lubango-Angola. Methodology: A descriptive study with a quantitative and qualitative approach to carry out a retrospective case study deliveries and newborns, records from 2014 to 2017. Final considerations: The implementation of this project may contribute to the improvement of clinical management support management of the hospital as well as facilitating access to information for research and scientific production.


2020 ◽  
Vol 2020 (4) ◽  
pp. 25-32
Author(s):  
Viktor Zheltov ◽  
Viktor Chembaev

The article has considered the calculation of the unified glare rating (UGR) based on the luminance spatial-angular distribution (LSAD). The method of local estimations of the Monte Carlo method is proposed as a method for modeling LSAD. On the basis of LSAD, it becomes possible to evaluate the quality of lighting by many criteria, including the generally accepted UGR. UGR allows preliminary assessment of the level of comfort for performing a visual task in a lighting system. A new method of "pixel-by-pixel" calculation of UGR based on LSAD is proposed.


Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1522
Author(s):  
Fuli Zhang ◽  
Zhaohui Yuan

The flexible manipulato is widely used in the aerospace industry and various other special fields. Control accuracy is affected by the flexibility, joint friction, and terminal load. Therefore, this paper establishes a robot dynamics model under the coupling effect of flexibility, friction, and terminal load, and analyzes and studies its control. First of all, taking the structure of the central rigid body, the flexible beam, and load as the research object, the dynamic model of a flexible manipulator with terminal load is established by using the hypothesis mode and the Lagrange method. Based on the balance principle of the force and moment, the friction under the influence of flexibility and load is recalculated, and the dynamic model of the manipulator is further improved. Secondly, the coupled dynamic system is decomposed and the controller is designed by the multivariable feedback controller. Finally, using MATLAB as the simulation platform, the feasibility of dynamic simulation is verified through simulation comparison. The results show that the vibration amplitude can be reduced with the increase of friction coefficient. As the load increases, the vibration can increase further. The trajectory tracking and vibration suppression of the manipulator are effective under the control method of multi-feedback moment calculation. The research is of great significance to the control of flexible robots under the influence of multiple factors.


2021 ◽  
Vol 15 ◽  
pp. 174830262110080
Author(s):  
Changjun Zha* ◽  
Qian Zhang* ◽  
Huimin Duan

Traditional single-pixel imaging systems are aimed mainly at relatively static or slowly changing targets. When there is relative motion between the imaging system and the target, sizable deviations between the measurement values and the real values can occur and result in poor image quality of the reconstructed target. To solve this problem, a novel dynamic compressive imaging system is proposed. In this system, a single-column digital micro-mirror device is used to modulate the target image, and the compressive measurement values are obtained for each column of the image. Based on analysis of the measurement values, a new recovery model of dynamic compressive imaging is given. Differing from traditional reconstruction results, the measurement values of any column of vectors in the target image can be used to reconstruct the vectors of two adjacent columns at the same time. Contingent upon characteristics of the results, a method of image quality enhancement based on an overlapping average algorithm is proposed. Simulation experiments and analysis show that the proposed dynamic compressive imaging can effectively reconstruct the target image; and that when the moving speed of the system changes within a certain range, the system reconstructs a better original image. The system overcomes the impact of dynamically changing speeds, and affords significantly better performance than traditional compressive imaging.


Sign in / Sign up

Export Citation Format

Share Document