Real-time trajectory resolution for a two-manipulator machining system

2006 ◽  
Vol 22 (S1) ◽  
pp. S51-S63 ◽  
Author(s):  
W. S. Owen ◽  
E. A. Croft ◽  
B. Benhabib
Keyword(s):  
Real Time ◽  
Machining System

Investigation on Wire Electrochemical Micro Machining

2007 ◽  
Author(s):  
Kun Wang ◽  
Di Zhu ◽  
Ningsong Qu
Keyword(s):  
Control System ◽  
Real Time ◽  
Machining Accuracy ◽  
Micro Machining ◽  
Wire Electrode ◽  
Micro Structure ◽  
Nanosecond Pulses ◽  
Machining System ◽  
Micrometer Scale ◽  
Micro Wire Electrode

Wire electrochemical micro machining (WEMM) using the online-fabricated micro wire electrode is proposed as a new method of micro machining. Based on electrochemical principle, the mechanism of nanosecond pulses WEMM was investigated. The hardware of the control system was founded using devices of virtual instruments, and the software of the system was designed based on Labwindows/CVI. The micrometer scale wire electrode was online fabricated, the diameter of wire electrode was real-time monitored by precisely measuring the variation in resistance of the electrode, and it is possible that accomplish the fabrication of wire electrode and the following processes continuously in the same machining system. The relations between the machining accuracy and parameters, such as velocity of feed forward and pulses parameters was experimentally studied, and a series of high-aspect-ration micro structure and multi-microgrooves were fabricated. The research of the paper sets up a firm foundation for application of the proposed wire electrochemical micro-machining.

Servo Scanning EDM for 3D Micro Structures

2007 ◽  
Author(s):  
Yong Li ◽  
Hao Tong ◽  
Jing Cui ◽  
Yang Wang
Keyword(s):  
Real Time ◽  
Servo Control ◽  
Machining Process ◽  
Machining Accuracy ◽  
Electrode Wear ◽  
Layer By Layer ◽  
Machining System ◽  
Scanning Path ◽  
Micro Structures ◽  
Discharge Gap

In electro discharge machining (EDM) for 3D micro structures, the electrode wear is serious and it needs to be compensated in process. To obtain a better balance of the machining accuracy and efficiency, a servo scanning EDM method is proposed for 3D micro structures, in which the electrode wear is compensated on real-time by controlling the discharge gap constant. It is supposed reasonably that the machining depth of each layer in servo scanning EDM is consistent if discharge gap is kept preferably. The servo scanning EDM strategies include the model design by Pro/Engineer (Pro/E), the plan and simulation of scanning path, and the machining process. The 3D micro structures are machined by scanning layer-by-layer under servo control of the electrode with monitoring discharge gap signal. The CAM, gap servo control, and real-time electrode wear compensating are integrated into the machining system. The evaluation experiments of servo scanning EDM and the typical machining experiments of 3D micro structures have been carried out. The machining results show that the electro discharge in the servo scanning EDM is more stable. Servo scanning micro EDM is propitious to improve machining accuracy and efficiency in 3D micro structures.

scholarly journals Development of a Real-Time Machining System for Metal Mold and Die.

1994 ◽  
Vol 60 (577) ◽  
pp. 2900-2905 ◽  
Author(s):  
Hiroshi Suzuki ◽  
Hiroshi Koresawa ◽  
Shinya Haramaki ◽  
Akihiro Hayashi
Keyword(s):  
Real Time ◽  
Metal Mold ◽  
Machining System

scholarly journals Novel electrical discharge machining system with real-time control and monitoring for preparing nanoiron colloid

2018 ◽  
Vol 10 (8) ◽  
pp. 168781401879170 ◽  
Author(s):  
Kuo-Hsiung Tseng ◽  
Chaur-Yang Chang ◽  
Mei-Jiun Chen ◽  
Yi-Kai Tseng
Keyword(s):  
Real Time ◽  
Electrical Discharge ◽  
Closed Loop ◽  
Electrical Discharge Machining ◽  
Proportional Integral Derivative ◽  
Proportional Integral Derivative Controller ◽  
Interelectrode Gap ◽  
Machining System ◽  
Arduino Microcontroller ◽  
Discharge Method

Nanoiron colloid is remarkably suitable for medical, engineering, and other applications because it exhibits excellent properties such as nontoxicity, biocompatibility, and high chemical stability. Because no studies have examined preparation of nanoiron colloid through electric spark discharge method, an electrical discharge machining system for preparing nanoiron colloid was developed in this study based on automated electric spark discharge method with real-time monitoring. An Arduino microcontroller, laser positioning technology, and closed-loop motor control were combined for automatic alignment of the two discharge electrodes. This electrode alignment method enabled achieving electrode alignment accuracy of 0.139 mm. The real-time monitoring applied the Ziegler–Nichols method with a proportional–integral–derivative controller for closed-loop control of the interelectrode gap that, compared with the manually tuned proportional–integral–derivative controller, increased the interelectrode gap discharge success rate from 22.25 to 28.99. A user-friendly interface and process parameters were realized through VisSim software, an Arduino microcontroller, and an RT/DAC4 PCI card. This design enabled obtaining data on process efficiency and providing real-time process diagnosis. Compared with colloids prepared using chemical methods, the nanoiron colloids prepared in this study contained only iron and oxygen; therefore, they would be safer for application in the human body. According to the UV-Vis and Zetasizer analyses, the absorbance peak of the nanoiron colloid prepared with this system ranged from 200 to 220 nm, and the zeta potential was approximately –11.6 mV with a diameter of approximately 155.9 nm. These results verified that this electrical discharge machining system can prepare nanoiron colloid featuring excellent suspension stability.

Some Recent Results in Quiescent Prominence Spectrometry

1979 ◽  
Vol 44 ◽  
pp. 41-47
Author(s):  
Donald A. Landman
Keyword(s):  
Real Time ◽  
Computer System ◽  
Spectral Response ◽  
Absolute Intensity ◽  
Solar Observatory ◽  
Target Size ◽  
Small Target ◽  
Signal Averaging ◽  
Quiescent Prominence

This paper describes some recent results of our quiescent prominence spectrometry program at the Mees Solar Observatory on Haleakala. The observations were made with the 25 cm coronagraph/coudé spectrograph system using a silicon vidicon detector. This detector consists of 500 contiguous channels covering approximately 6 or 80 Å, depending on the grating used. The instrument is interfaced to the Observatory’s PDP 11/45 computer system, and has the important advantages of wide spectral response, linearity and signal-averaging with real-time display. Its principal drawback is the relatively small target size. For the present work, the aperture was about 3″ × 5″. Absolute intensity calibrations were made by measuring quiet regions near sun center.

Video real-time imaging of artificial membranes during freeze-drying by cryo-electron microscopy

1988 ◽  
Vol 46 ◽  
pp. 16-17
Author(s):  
Alan S. Rudolph ◽  
Ronald R. Price
Keyword(s):  
Real Time ◽  
Self Assembly ◽  
Freeze Drying ◽  
Video Capture ◽  
Drying Process ◽  
Artificial Membranes ◽  
The Past ◽  
Cryo Electron Microscopy ◽  
Spherical Structures ◽  
Capture Techniques

We have employed cryoelectron microscopy to visualize events that occur during the freeze-drying of artificial membranes by employing real time video capture techniques. Artificial membranes or liposomes which are spherical structures within internal aqueous space are stabilized by water which provides the driving force for spontaneous self-assembly of these structures. Previous assays of damage to these structures which are induced by freeze drying reveal that the two principal deleterious events that occur are 1) fusion of liposomes and 2) leakage of contents trapped within the liposome [1]. In the past the only way to access these events was to examine the liposomes following the dehydration event. This technique allows the event to be monitored in real time as the liposomes destabilize and as water is sublimed at cryo temperatures in the vacuum of the microscope. The method by which liposomes are compromised by freeze-drying are largely unknown. This technique has shown that cryo-protectants such as glycerol and carbohydrates are able to maintain liposomal structure throughout the drying process.

An Interactive Minicomputer Program for the Indexing and Simulation of Electron Diffraction Patterns

1976 ◽  
Vol 34 ◽  
pp. 542-543
Author(s):  
R.P. Goehner ◽  
W.T. Hatfield ◽  
Prakash Rao
Keyword(s):  
Electron Diffraction ◽  
Real Time ◽  
Pattern Analysis ◽  
Flow Diagram ◽  
Hard Copy ◽  
Time Analysis ◽  
Real Time Analysis ◽  
Transmission Electron ◽  
One Step ◽  
Diffraction Patterns

Computer programs are now available in various laboratories for the indexing and simulation of transmission electron diffraction patterns. Although these programs address themselves to the solution of various aspects of the indexing and simulation process, the ultimate goal is to perform real time diffraction pattern analysis directly off of the imaging screen of the transmission electron microscope. The program to be described in this paper represents one step prior to real time analysis. It involves the combination of two programs, described in an earlier paper(l), into a single program for use on an interactive basis with a minicomputer. In our case, the minicomputer is an INTERDATA 70 equipped with a Tektronix 4010-1 graphical display terminal and hard copy unit.A simplified flow diagram of the combined program, written in Fortran IV, is shown in Figure 1. It consists of two programs INDEX and TEDP which index and simulate electron diffraction patterns respectively. The user has the option of choosing either the indexing or simulating aspects of the combined program.

Microstructural investigation of surface roughness in MBE-grown AlAs

1995 ◽  
Vol 53 ◽  
pp. 454-455
Author(s):  
R. Rajesh ◽  
R. Droopad ◽  
C. H. Kuo ◽  
R. W. Carpenter ◽  
G. N. Maracas
Keyword(s):  
Thin Film ◽  
Real Time ◽  
Growth Control ◽  
Native Oxide ◽  
Effusion Cell ◽  
Surface Oxide Layer ◽  
Microstructural Investigation ◽  
Mbe Growth ◽  
Film Substrate ◽  
And Control

Knowledge of material pseudodielectric functions at MBE growth temperatures is essential for achieving in-situ, real time growth control. This allows us to accurately monitor and control thicknesses of the layers during growth. Undesired effusion cell temperature fluctuations during growth can thus be compensated for in real-time by spectroscopic ellipsometry. The accuracy in determining pseudodielectric functions is increased if one does not require applying a structure model to correct for the presence of an unknown surface layer such as a native oxide. Performing these measurements in an MBE reactor on as-grown material gives us this advantage. Thus, a simple three phase model (vacuum/thin film/substrate) can be used to obtain thin film data without uncertainties arising from a surface oxide layer of unknown composition and temperature dependence.In this study, we obtain the pseudodielectric functions of MBE-grown AlAs from growth temperature (650°C) to room temperature (30°C). The profile of the wavelength-dependent function from the ellipsometry data indicated a rough surface after growth of 0.5 μm of AlAs at a substrate temperature of 600°C, which is typical for MBE-growth of GaAs.

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