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Full-Text Articles in Engineering
Discrete Cosine Transform Based Shift Estimation For Fringe Pattern Profilometry Using Generalized Analysis Model, Jose F. Chicharo, Jiangtao Xi, Yingsong Hu, Zongkai Yang, Enbang Li
Discrete Cosine Transform Based Shift Estimation For Fringe Pattern Profilometry Using Generalized Analysis Model, Jose F. Chicharo, Jiangtao Xi, Yingsong Hu, Zongkai Yang, Enbang Li
Faculty of Engineering - Papers (Archive)
This paper presents a new analysis algorithm to carry out profile measure- ment with low computational complexity and less noise-sensitivity. Firstly, a discrete cosine transform (DCT) based representation method is introduced to express the height distribution of the three-dimensional surface. Then, a novel shift estimation algorithm, called DCT based shift estimation (DCT-SE) is presented to reconstruct three-dimensional object surfaces by using the proposed expression and the generalized analysis model. The advantage of DCT-SE is that without loss of measurement precise it provides lower computational complexity to implement three-dimensional reconstruction from distorted fringe patterns and at the same time survives from …
A Microslip Model Of The Bonding Process In Ultrasonic Wire Bonders Part I: Transient Response, C M. Hu, N Guo, H Du, W H. Li, M Chen
A Microslip Model Of The Bonding Process In Ultrasonic Wire Bonders Part I: Transient Response, C M. Hu, N Guo, H Du, W H. Li, M Chen
Faculty of Engineering - Papers (Archive)
Ultrasonic wire bonders with precision capillary tips are widely used for bonding electrical wires to IC chips and circuits. The industry is driving wire-bonding technology towards increased yields, decreased pitch, and ever decreasing cost. However, many technical and material issues will be involved in achieving these goals, such as bond quality monitoring, new failure modes, reliability problems in new plastic mold compounds, and increasing wire sweep problems, in particular lack of the quantitative understanding and validated mathematical model of the bonding process. In this paper, a microslip model is proposed for the bonding process based on the bonding pattern observed, …
Dynamic Model Simplification Of Serial Manipulators, Subir Kumar Saha, Bijan Shirinzadeh, Gursel Alici
Dynamic Model Simplification Of Serial Manipulators, Subir Kumar Saha, Bijan Shirinzadeh, Gursel Alici
Faculty of Engineering - Papers (Archive)
Simplicity in the dynamics model of a serial robot manipulator greatly enhances the speed of its control and the associated hardware implementation. Since the motion of one link influences the torque or force required at the other joints, the control becomes difficult. This is referred as dynamic coupling. In this paper, it is proposed to simplify the robot's dynamic coupling by suitably choosing the manipulator’s kinematic and dynamic parameters. The intention is to make the Generalized Inertia Matrix (GIM) of the serial manipulator associated with its dynamic equations of motion diagonal and/or constant. Such choice automatically ensures the associated convective …
A New Model For Thermal Conductivity In Nanofluids, Pei Tillman, James M. Hill
A New Model For Thermal Conductivity In Nanofluids, Pei Tillman, James M. Hill
Faculty of Engineering - Papers (Archive)
Nanofluids exhibit enhanced thermal conductivity superior to traditional heat transfer fluids. The conventional theoretical models cannot explain the large enhancement of the thermal conductivity of nanofluids. It has been proposed that an interfacial structure formed by liquid molecular layering might play an important role. To date there is no known procedure to properly calculate the nanolayer thickness, and all previous investigators arbitrarily adopt a layer thickness which is consistent with experimental results. Here we investigate the thermal conductivity structure of this interfacial layer and its impact on the effective thermal conductivity and an expression for the thermal conductivity profile in …