scholarly journals A Novel Method to Reduce the Laser Drilling Time for Hole Cluster considering the Influence of Residual Vibration of the Sample Stage

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Xiaodong Wang ◽  
Bin Liu ◽  
Xuesong Mei ◽  
Jun Yang ◽  
Xialun Yun ◽  
...  
Keyword(s):  
Laser Irradiation ◽  
Delay Time ◽  
Laser Drilling ◽  
Residual Vibration ◽  
Processing Efficiency ◽  
Common Solution ◽  
Vibration Attenuation ◽  
Novel Method ◽  
Point To Point ◽  
Drilling Time

In large areas of laser drilling, the residual vibration occurs when the sample stage moves in PTP (Point to Point) movement. It affects the surface quality and processing efficiency of the holes. The common solution for this problem is to set the laser irradiation delay time by the controller to wait for the residual vibration attenuation, but the whole drilling circle will increase. In this paper, a new method is introduced to reduce the laser drilling circle. By setting the allowable threshold of the residual vibration for the subsequent process, the sum of the time in deceleration segment of the trapezoidal moving profile, and the time when the residual vibration attenuates below the amplitude threshold (ST) can be minimized as the optimization goal. The results show that for a given operating speed, there is always an optimum acceleration value for the deceleration segment of the trapezoidal moving profile, which minimizes the ST value. Further, the delay time for laser irradiation can also be estimated according to the optimal acceleration during laser drilling.

Influence of the Laser Irradiation on the Delay Time of Start of Ar-Hg Discharge

2005 ◽  
Vol 125 (3) ◽  
pp. 235-240
Author(s):  
Terukazu Matsugi ◽  
Katsunori Arase ◽  
Hideki Motomura ◽  
Masafumi Jinno ◽  
Masaharu Aono
Keyword(s):  
Laser Irradiation ◽  
Delay Time

scholarly journals Robotic Control by Teleoperation and Delay Time Issues Using the Internet

2020 ◽  
Vol 14 ◽  
pp. 01-08
Author(s):  
Anuntachai Machim ◽  
Murray John Lawn ◽  
Ikuo Yamamoto
Keyword(s):  
Delay Time ◽  
Virtual Private Network ◽  
Critical Systems ◽  
Robotic Control ◽  
Daily Lives ◽  
Average Transmission ◽  
Set Up ◽  
Point To Point ◽  
Private Network ◽  
Internet Networks

Internet usage has become an essential part of our daily lives, it has become universal. The aim of this research is to consider existing Internet-based networks with regard to their support for the remote operation of robotic technology, in particular, looking at transmission speed and delay time as it relates to teleoperation. Currently dedicated connections are typically used when a high Quality of Service (QoS) is required for mission critical services or safety-critical systems (SCS), however such connections are very expensive to set up and maintain. Therefore, this study focuses on modifying existing internet networks in a manner to provide a better QoS with little additional cost. Using a number of microcontrollers, computers, and routers, two different protocols were used to control a robotic device remotely. Use of the Point-to-Point Tunnelling Protocol (PPTP) used for implementing a Virtual Private Network (VPN) was found to provide higher average transmission speeds compared to the using a Uniform Resource Locator (URL) which is a regular internet connection.

Friction-Compensating Command Shaping for Vibration Reduction

2004 ◽  
Vol 127 (4) ◽  
pp. 307-314 ◽  
Author(s):  
Jason Lawrence ◽  
William Singhose ◽  
Keith Hekman
Keyword(s):  
Steady State ◽  
Coulomb Friction ◽  
Vibration Reduction ◽  
Input Shaping ◽  
Residual Vibration ◽  
Command Shaping ◽  
Point Motion ◽  
Common Operation ◽  
Point To Point ◽  
Theoretical Developments

Fast and accurate point-to-point motion is a common operation for industrial machines, but vibration will frequently corrupt such motion. This paper develops commands that can move machines without vibration, even in the presence of Coulomb friction. Previous studies have shown that input shaping can be used on linear systems to produce point-to-point motion with no residual vibration. This paper extends command-shaping theory to nonlinear systems, specifically systems with Coulomb friction. This idea is applied to a PD-controlled mass with Coulomb friction to ground. The theoretical developments are experimentally verified on a solder cell machine. The results show that the new commands allow the proportional gain to be increased, resulting in reduced rise time, settling time, and steady-state error.

scholarly journals Rest-to-Rest Motion of an Experimental Flexible Structure Subject to Friction: Linear Programming Approach

2010 ◽  
Vol 132 (1) ◽  
Author(s):  
Rajaey Kased ◽  
Tarunraj Singh
Keyword(s):  
Linear Programming ◽  
Controller Design ◽  
Open Loop ◽  
Programming Approach ◽  
Pulse Control ◽  
Test Bed ◽  
Residual Vibration ◽  
Linear Programming Approach ◽  
Point To Point ◽  
Harmonic System

A linear programming approach designed to eliminate the residual vibration of the two-mass harmonic system subject to friction and undergoing a point-to-point maneuver is proposed and implemented on an experimental test bed. Techniques for design of positive pulse control profiles for nonrobust and robust open loop controller design are explored, where the positive pulses initiate motion and the friction force brings the system to rest. It is shown that consistent results can be obtained from experiments and the robustness against frequency uncertainty results in the reduction in residual vibration as well as steady-state error.

Sensitivity Analysis of Vibration Suppression Based on the Multiple-Mode Negative Impulses Input Shapers

2012 ◽  
Vol 189 ◽  
pp. 312-316
Author(s):  
Yue Zhan Wang ◽  
Qi Bo Yan ◽  
Bing Li ◽  
Yu Lan Wei
Keyword(s):  
Sensitivity Analysis ◽  
Numerical Simulations ◽  
Delay Time ◽  
Parallel Manipulator ◽  
Vibration Suppression ◽  
System Response ◽  
Input Shaping ◽  
Residual Vibration ◽  
Multiple Mode

The structure of a 3-DOF parallel manipulator is presented. The methodologies of multiple-mode negative impulses input shaping is introduced, which can decrease the delay time of the system response while the residual vibration is suppressed. The parameters of two-mode negative impulses and positive impulses input shapers of the 3-DOF manipulator are presented. The sensitivity analysis of these input shapers are carried out through numerical simulations, and the robust of the input shapers are presented and compared.

Experimental Study on Light Intensity Profile in an Axisymmetric Thin Shell Irradiated by a Light

2013 ◽  
Vol 740 ◽  
pp. 640-643
Author(s):  
Ching Yen Ho ◽  
C. Ma
Keyword(s):  
Experimental Study ◽  
Solar Energy ◽  
Light Intensity ◽  
Intensity Distribution ◽  
Thin Shell ◽  
Laser Light ◽  
Laser Drilling ◽  
Geometric Optics ◽  
Light Intensity Distribution ◽  
Novel Method

This paper experimentally investigates light intensity distribution in a paraboloid of thin shell irradiated by a laser. Light intensity distribution needs to be understood for solar energy heat receiver or laser drilling cavity. A novel method is utilized to measure the light intensity distribution in a paraboloid of thin shell irradiated by a laser. The results are explained by simple geometric optics.

scholarly journals An Efficient and Fast Partial Template Matching Technique – Enhancement in Normalized Cross Correlation

2019 ◽  
Vol 9 (1) ◽  
pp. 7232-7237
Keyword(s):  
Image Processing ◽  
Execution Time ◽  
Template Matching ◽  
Absolute Difference ◽  
Processing Efficiency ◽  
Memory Space ◽  
Matching Technique ◽  
Speed Up ◽  
Novel Method ◽  
Window Approach

Template matching forms the basis of many image processing algorithms and hence the computer vision algorithms. There are many existing template matching algorithms like Sum of Absolute Difference (SAD), Normalized SAD (NSAD), Correlation methods (CORR), Normalized CORR(NCORR), Sum of Squared Difference (SSD), and Normalized SSD(NSSD). In general, as image requires more memory space for storage and much time for processing. The above said methods involves much computation. In any processing, efficiency constraints include many factors, especially accuracy of the results and speed of processing. An approach to reduce the execution time is always most appreciated. As a result of this, a novel method of partial NCC (PNCC) template matching technique is proposed in this paper. A block window approach is used to reduce the number of operations and hence to speed up the processing. A comparative study between existing NCC algorithm and the proposed partial NCC, PNCC algorithm is done. It is experimented and results proves that the execution time is reduced by 8 - 47 times approximately based on the various template images for different main images in PNCC. The accuracy of the result obtained is 100%. This proposed algorithm works for various types of images. The experiment is repeated for various sizes of templates and different sizes of main image. Further improvement in the speed of execution can be achieved by implementation of the proposed algorithm using parallel processors. It may find its importance in the real time image processing

Trajectory Synthesis for Selective Elimination of High Frequency Actuating Torque Harmonics

1998 ◽  
Author(s):  
Q. J. Ge ◽  
J. Rastegar ◽  
M. Mattice
Keyword(s):  
High Frequency ◽  
Settling Time ◽  
Residual Vibration ◽  
Harmonic Content ◽  
Selective Elimination ◽  
Computer Controlled ◽  
Point To Point ◽  
High Frequency Harmonic ◽  
Frequency Harmonic

Abstract This paper deals with the problem of synthesizing joint trajectories of computer controlled machinery with tailored harmonic content for the actuating torques required to track the trajectories. For point-to-point motions with zero initial and final velocities and accelerations, a method is presented for shaping the harmonic content of the joint trajectories for the purpose of eliminating a specified high-frequency harmonic from the actuating torques. With such trajectories, the machine can perform the synthesized tasks with less residual vibration and increased settling time.

Vibration attenuation analysis of compressional gas cushion press nanoimprint lithography system

2013 ◽  
Vol 228 (9) ◽  
pp. 1634-1642 ◽  
Author(s):  
Liu Chaoran ◽  
Yue Jinzhao ◽  
Li Tianhao ◽  
Xia Weiwei ◽  
Li Dongxue ◽  
...  
Keyword(s):  
Nanoimprint Lithography ◽  
Theoretical Models ◽  
Physical Parameters ◽  
Attenuation Effect ◽  
Internal Structures ◽  
Vibration Attenuation ◽  
System Vibration ◽  
Novel Method ◽  
Lithography System ◽  
Great Development

Nanoimprint lithography has a great development in decades. Compressional gas cushion press is a novel method in improving the uniformity in nanoimprint lithography process. Based on compressional gas cushion press nanoimprint lithography system, an attenuation ring is added between the chamber wall and the pedestal. The attenuation ring decreases the influence of system vibration on the fidelity of patterning. The physical parameters of the attenuation material are optimized based on the theoretical models of the vibration attenuation and mechanical calculation. According to the optimization physical parameters, Young's modulus of a perfect material of attenuation ring should be smaller than 8 MPa, and Poisson's ratio should be close to 0.5. Therefore, natural rubber is employed as the material of attenuation ring. The simulation results based on COMSOL indicate that nested rectangular structure has the best attenuation effect among the four simulated internal structures. It provides technological supporting for the establishment of attenuation ring in compressional gas cushion press nanoimprint lithography system.

Command Shaping Slewing Motions for Tower Cranes

2010 ◽  
Vol 132 (1) ◽  
Author(s):  
Jason Lawrence ◽  
William Singhose
Keyword(s):  
Nonlinear Dynamics ◽  
Rotational Motion ◽  
Effective Control ◽  
Input Shaping ◽  
Residual Vibration ◽  
Command Shaping ◽  
Tower Crane ◽  
Control Scheme ◽  
Point To Point ◽  
Gantry Cranes

Input shaping has been shown to be a practical and effective control scheme for reducing payload swing on industrial bridge and gantry cranes. However, when applied to tower cranes, standard input shapers will have degraded performance due to the nonlinear dynamics of rotational motion. To alleviate this problem, two new command generators for tower cranes are developed for a point-to-point slewing motion. It is shown that standard shaping techniques greatly reduce oscillation and the new tower crane command generators cause even less residual vibration. Simulations and experiments verify the results.

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