Methods of Robotics and the Pseudoinverse to Obtain the Least-Squares Fit of Measured Points on Line-Profiles

2012 ◽  
Author(s):  
J. K. Davidson ◽  
S. B. Savaliya ◽  
Y. He ◽  
Jami J. Shah
Keyword(s):  
Quality Control ◽  
Least Squares ◽  
Line Profile ◽  
Manufacturing Process ◽  
Turbine Blades ◽  
Computational Method ◽  
Line Profiles ◽  
Cross Sectional ◽  
Least Squares Fit ◽  
On Line

Tolerances on line profiles are used to control cross-sectional shapes of parts, such as turbine blades. A full life cycle for many mechanical devices depends (i) on a wise assignment of tolerances during design and (ii) on careful quality control of the manufacturing process to ensure adherence to the specified tolerances. This paper describes a new method to improve the quality control of a manufacturing process by converting measured points on a part to a geometric entity that can be compared directly with tolerance specifications. The focus of this paper is the development of a new computational method for obtaining the least-squares fit of a set of points that have been measured with a coordinate measurement machine along a line-profile. The pseudo-inverse of a rectangular matrix is used to convert the measured points to the least-squares fit of the profile. A numerical example is included for a convex line-profile that is formed from line- and circular arc-segments.

Tolerance-Maps for Line-Profiles Constructed From Boolean Operations on Primitive T-Map Elements

2013 ◽  
Author(s):  
Y. He ◽  
J. K. Davidson ◽  
Jami J. Shah
Keyword(s):  
Line Profile ◽  
Line Profiles ◽  
Tolerance Zone ◽  
Compressor Blades ◽  
Cross Sectional ◽  
Math Model ◽  
True Profile ◽  
Profile Tolerance ◽  
On Line ◽  
Computer Automation

For purposes of automating the assignment of tolerances during design, a math model, called the Tolerance-Map (T-Map), has been produced for most of the tolerance classes that are used by designers. Each T-Map is a hypothetical point-space that represents the geometric variations of a feature in its tolerance-zone. Of the six tolerance classes defined in the ASME/ANSI/ISO Standards, only one attempt has been made at modeling line-profiles [1], and the method used is an intuitive kinematic description of the allowable displacements of the middle-sized profile within its tolerance-zone. The objective of this paper is to describe an alternative method of construction, one that is much more amenable to computer automation, to obtain the T-Map of any line-profile. Tolerances on line-profiles are used to control cross-sectional shapes of parts, even mildly twisted ones such as those on turbine or compressor blades. Such tolerances limit geometric manufacturing variations to a specified two-dimensional tolerance-zone, i.e. an area, the boundaries to which are curves parallel to the true profile. The single profile tolerance may be used to control position, orientation, and form of the profile. The new method requires decomposing a profile into segments, creating a solid-model T-Map primitive for each, and then combining these by the Boolean intersection to generate the T-Map for a complete line profile of any shape. To economize on length, the scope of this paper is limited to line-profiles having any polygonal shape.

scholarly journals Least-squares Fit of Measured Points for Square Line-profiles

Procedia CIRP ◽  
2013 ◽  
Vol 10 ◽  
pp. 203-210 ◽  
Author(s):  
J. Davidson ◽  
S. Savaliya ◽  
Jami J. Shah
Keyword(s):  
Least Squares ◽  
Line Profiles ◽  
Least Squares Fit

Using Planar Kinematics to Construct the Full 4-D Tolerance-Map for a Line-Profile

2013 ◽  
Author(s):  
S. B. Savaliya ◽  
J. K. Davidson ◽  
Jami J. Shah
Keyword(s):  
Companion Paper ◽  
Line Profiles ◽  
Tolerance Zone ◽  
Compressor Blades ◽  
Cross Sectional ◽  
Math Model ◽  
True Profile ◽  
Triangular Profile ◽  
On Line ◽  
The Common

Tolerances on line-profiles are used to control cross-sectional shapes of parts, even mildly twisted ones such as those on turbine or compressor blades. Such tolerances limit geometric manufacturing variations to a specified two-dimensional tolerance-zone, i.e. an area, the boundaries to which are curves parallel to the true profile. The single profile tolerance may be used to control position, orientation, and form of the profile. For purposes of automating the assignment of tolerances during design, a math model, called the Tolerance-Map (T-Map), has been produced for most of the tolerance classes that are used by designers. Each T-Map is a hypothetical point-space that represents the geometric variations of a feature in its tolerance-zone. Of the six tolerance classes defined in the ASME/ANSI/ISO Standards, only one attempt has been made at modeling line-profiles [1], and the method used is a kinematic description, based largely on intuition, of the allowable displacements of the middle-sized profile within its tolerance-zone. The result presented is a 4-D double pyramid having a 3-D shape for the common base. Allowable small changes in size represent the fourth dimension in the altitude-direction of the pyramids. However, that work is limited to square, rectangular, and right-triangular profile shapes for which the 3-D transverse sections (called hypersections) of the 4-D T-Map are all geometrically similar to the base because the boundaries are doubly traced. For more generally shaped profiles, [2] the hypersections are not geometrically similar to the base. The objective of this paper is to expand the kinematic description of a profile in its tolerance-zone to include the changing constraints that take place as size is incremented or decremented within the allowable tolerance-range. It provides validation of a different method that is described in a companion paper [3].

scholarly journals Overloaded and fractured stellar winds

2003 ◽  
Vol 212 ◽  
pp. 56-60 ◽  
Author(s):  
Achim Feldmeier ◽  
Lida M. Oskinova ◽  
Wolf-Rainer Hamann ◽  
Stanley P. Owocki
Keyword(s):  
Wind Speed ◽  
Line Profile ◽  
Propagation Speed ◽  
Stellar Winds ◽  
Line Profiles ◽  
X Ray ◽  
On Line

We discuss the connection between wind overloading and discrete absorption components in P-Cygni line profiles from O-type stars. Overloading can create horizontal plateaus in the radial wind speed that cause the extra absorption in the line profile. The upstream propagation speed of these velocity plateaus is analyzed. The second part of the paper deals with X-ray emission from O-type stars. X-ray line profiles observed with Chandra and XMM-Newton are often symmetric, contrary to what is expected for lines from a homogeneous wind. We discuss the influence on line symmetry of photon escape channels in a strongly clumped wind.

Application of partial least squares methods to a terephthalic acid manufacturing process for product quality control

2003 ◽  
Vol 20 (6) ◽  
pp. 977-984 ◽  
Author(s):  
In-Su Han ◽  
Minjin Kim ◽  
Chang-Hyun Lee ◽  
Woonou Cha ◽  
Byoung-Kyoung Ham ◽  
...  
Keyword(s):  
Quality Control ◽  
Product Quality ◽  
Least Squares ◽  
Partial Least Squares ◽  
Manufacturing Process ◽  
Terephthalic Acid ◽  
Product Quality Control

Emerging Techniques for the Characterization of Nano-Mechanical Properties of Integrated Circuit Components

2008 ◽  
Author(s):  
Nicholas Randall ◽  
Rahul Premachandran Nair
Keyword(s):  
Mechanical Properties ◽  
Quality Control ◽  
Integrated Circuits ◽  
Integrated Circuit ◽  
Manufacturing Process ◽  
Solder Bumps ◽  
Initial Work ◽  
Circuit Components ◽  
Materials Used

Abstract With the growing complexity of integrated circuits (IC) comes the issue of quality control during the manufacturing process. In order to avoid late realization of design flaws which could be very expensive, the characterization of the mechanical properties of the IC components needs to be carried out in a more efficient and standardized manner. The effects of changes in the manufacturing process and materials used on the functioning and reliability of the final device also need to be addressed. Initial work on accurately determining several key mechanical properties of bonding pads, solder bumps and coatings using a combination of different methods and equipment has been summarized.

scholarly journals Fractal Nature of Advanced Ni-Based Superalloys Solidified on Board the International Space Station

2021 ◽  
Vol 13 (9) ◽  
pp. 1724
Author(s):  
Vojislav Mitić ◽  
Cristina Serpa ◽  
Ivana Ilić ◽  
Markus Mohr ◽  
Hans-Jörg Fecht
Keyword(s):  
International Space Station ◽  
Fractal Analysis ◽  
Power Plants ◽  
Materials Science ◽  
Structural Characteristics ◽  
Turbine Blades ◽  
Space Station ◽  
Casting Process ◽  
Cross Sectional ◽  
International Space

Materials science is highly significant in space program investigation, energy production and others. Therefore, designing, improving and predicting advanced material properties is a crucial necessity. The high temperature creep and corrosion resistance of Ni-based superalloys makes them important materials for turbine blades in aircraft engines and land-based power plants. The investment casting process of turbine blades is costly and time consuming, which makes process simulations a necessity. These simulations require fundamental models for the microstructure formation. In this paper, we present advanced analytical techniques in describing the microstructures obtained experimentally and analyzed on different sample’s cross-sectional images. The samples have been processed on board the International Space Station using the MSL-EML device based on electromagnetic levitation principles. We applied several aspects of fractal analysis and obtained important results regarding fractals and Hausdorff dimensions related to the surface and structural characteristics of CMSX-10 samples. Using scanning electron microscopy (SEM), Zeiss LEO 1550, we analyzed the microstructure of samples solidified in space and successfully performed the fractal reconstruction of the sample’s morphology. We extended the fractal analysis on the microscopic images based on samples solidified on earth and established new frontiers on the advanced structures prediction.

Analysis of the information management system in the manufacturing process of cigarette enterprises using fuzzy AHP

2021 ◽  
pp. 1-11
Author(s):  
Song Gang ◽  
Wang Xiaoming ◽  
Wu Junfeng ◽  
Li Shufang ◽  
Liu Zhuowen ◽  
...  
Keyword(s):  
Quality Control ◽  
Production Process ◽  
Information Management ◽  
Manufacturing Process ◽  
Management System ◽  
Fuzzy Ahp ◽  
Control Process ◽  
Information Management System ◽  
Manufacturing Execution System ◽  
Quality Control Process

In view of the production quality management of filter rods in the manufacturing and execution process of cigarette enterprises, this paper analyzes the necessity of implementing the manufacturing execution system (MES) in the production process of filter rods. In this paper, the filter rod quality system of cigarette enterprise based on MES is fully studied, and the constructive information management system demand analysis, cigarette quality control process, system function module design, implementation and test effect are given. This paper utilizes the Fuzzy analytic hierarchy process to find the optimal system for processing the manufacturing of cigarette. The implementation of MSE based filter rod quality information management system for a cigarette enterprise ensures the quality control in the cigarette production process. Through visualization, real-time and dynamic way, the information management of cigarette production is completed, which greatly improves the quality of cigarette enterprise manufacturing process.

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