Constraint Coordination for the Single Motion State

1973 ◽  
Vol 95 (2) ◽  
pp. 641-647
Author(s):  
P. W. Eschenbach ◽  
D. Tesar
Keyword(s):  
Input Constraint ◽  
Motion State ◽  
Transmission Angle ◽  
Secondary Constraint ◽  
Industrial Problem ◽  
Planar Body

The methods of constraint coordination are derived and applied to an industrial problem to synthesize a mechanism solution. The motion of an input constraint of unknown proportions is coordinated with the motion of a planar body to yield constraint dimensions. The motion of a secondary constraint is chosen to optimize the transmission angle over a cycle of motion.

Research on an axial-mounted dual magnetostrictive material rods-based electro-hydrostatic actuator

2021 ◽  
pp. 1045389X2110145
Author(s):  
Yuchuan Zhu ◽  
Chang Liu ◽  
Yunze Song ◽  
Long Chen ◽  
Yulei Jiang ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Flow Rate ◽  
Flow Distribution ◽  
Maximum Flow ◽  
Magnetostrictive Material ◽  
Simulation Techniques ◽  
Motion State ◽  
New Type ◽  
Output Characteristics ◽  
Active Rectification

In this paper, an electro-hydrostatic actuator driven by dual axial-mounted magnetostrictive material rods-based pumps (MMPs) with a new type of active rectification valve is designed in the current study. Based on flow distribution of the active rectification valve and driving energy provided by two MMPs, the actuator can output continuous and bidirectional displacement. By establishing a mathematical model of the actuating system, using simulation techniques, the change rule of hydraulic cylinder’s motion state caused by different driving signals are studied and analyzed. Test equipment platform is constructed in the laboratory to test the output characteristics and confirm the feasibility of the new concept. The experimental results indicate that the maximum flow rate can reach approximately 2.7 L·min−1, while the operating frequency is 180 Hz.

scholarly journals Molecular dynamics simulation of sI methane hydrate under compression and tension

2020 ◽  
Vol 18 (1) ◽  
pp. 69-76
Author(s):  
Qiang Wang ◽  
Qizhong Tang ◽  
Sen Tian
Keyword(s):  
Molecular Dynamics ◽  
Methane Hydrate ◽  
Fracture Process ◽  
Md Simulation ◽  
Maximum Stress ◽  
Dynamics Simulation ◽  
Tensile Fracture ◽  
Maximum Compressive Stress ◽  
Motion State ◽  
Stress States

AbstractMolecular dynamics (MD) analysis of methane hydrate is important for the application of methane hydrate technology. This study investigated the microstructure changes of sI methane hydrate and the laws of stress–strain evolution under the condition of compression and tension by using MD simulation. This study further explored the mechanical property and stability of sI methane hydrate under different stress states. Results showed that tensile and compressive failures produced an obvious size effect under a certain condition. At low temperature and high pressure, most of the clathrate hydrate maintained a stable structure in the tensile fracture process, during which only a small amount of unstable methane broke the structure, thereby, presenting a free-motion state. The methane hydrate cracked when the system reached the maximum stress in the loading process, in which the maximum compressive stress is larger than the tensile stress under the same experimental condition. This study provides a basis for understanding the microscopic stress characteristics of methane hydrate.

A Statistical Approach to Improve Wafer Fabrication Yield

2002 ◽  
Author(s):  
Nael Barakat ◽  
Hesham Enshasy
Keyword(s):  
Statistical Approach ◽  
Product Yield ◽  
Wafer Fabrication ◽  
Statistical Process ◽  
Control Approach ◽  
Yield Increase ◽  
Cost Cutting ◽  
Knowing That ◽  
The Individual ◽  
Industrial Problem

In spite of the recent advancements in wafer fabrication techniques, devices are still being individually checked and modified. This is due to the fact that the general manufacturing processes involved in wafer production have their inherent inconsistencies. As a consequence, individual devices show differences in characteristics that would render a big group of them operating out of the range of the pre-set spec limits. Therefore they would require types of modifications specific to the individual device. Knowing that the resources spent on checking and eliminating out-of-spec devices before they reach the customer are very significant, the manufacturing operation becomes hardly profitable. These wafers normally carry devices in the range of a thousand or so, making a statistical approach very attractive. In this paper, an actual industrial problem in wafer fabrication to the desired specifications is presented. The problem shows in passive filters built using Surface Acoustic Wave (SAW) theory. A solution considering a statistical process control approach to the population of devices on the wafer is proposed. The results of applying this solution are realized in significant product yield increase, huge cost cutting, and automation promotion and application.

Simulation of Valve Position Feedback Mechanism Based on Pro/E and ADAMS

2014 ◽  
Vol 721 ◽  
pp. 244-248
Author(s):  
You Jun Fan ◽  
Fei Li ◽  
Hua Tian Zhao
Keyword(s):  
Feedback Mechanism ◽  
Dynamics Model ◽  
Joint Simulation ◽  
Force And Motion ◽  
Motion State ◽  
Position Feedback ◽  
Displacement Angle ◽  
Valve Position ◽  
Relationship Of ◽  
The Relationship

In traditional valve position feedback mechanism design, it is tested repeatedly and improvement after processing prototype, the process is complex and workload. Using Pro/E and ADAMS, the overall mechanical structure of the valve position feedback mechanism for joint simulation, and an analysis of the kinematics and dynamics model, simplified the design process of the repeated calculation, get the relationship of stem displacement-angle between gear, gear meshing force and motion state of the stem, the simulation value compared with the theoretical value, tallies with the data and shows that the simulation is reasonable.

scholarly journals Slow-motion state of mind

Science ◽  
2016 ◽  
Vol 353 (6302) ◽  
pp. 883-884
Author(s):  
G. Riddihough
Keyword(s):  
Slow Motion ◽  
Motion State ◽  
State Of Mind

scholarly journals Ego-Motion Estimation Using Recurrent Convolutional Neural Networks through Optical Flow Learning

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 222
Author(s):  
Baigan Zhao ◽  
Yingping Huang ◽  
Hongjian Wei ◽  
Xing Hu
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Motion Estimation ◽  
Optical Flow ◽  
Feature Representation ◽  
Sequential Learning ◽  
Navigation Systems ◽  
Motion State ◽  
Training Schemes ◽  
Sequential Images

Visual odometry (VO) refers to incremental estimation of the motion state of an agent (e.g., vehicle and robot) by using image information, and is a key component of modern localization and navigation systems. Addressing the monocular VO problem, this paper presents a novel end-to-end network for estimation of camera ego-motion. The network learns the latent subspace of optical flow (OF) and models sequential dynamics so that the motion estimation is constrained by the relations between sequential images. We compute the OF field of consecutive images and extract the latent OF representation in a self-encoding manner. A Recurrent Neural Network is then followed to examine the OF changes, i.e., to conduct sequential learning. The extracted sequential OF subspace is used to compute the regression of the 6-dimensional pose vector. We derive three models with different network structures and different training schemes: LS-CNN-VO, LS-AE-VO, and LS-RCNN-VO. Particularly, we separately train the encoder in an unsupervised manner. By this means, we avoid non-convergence during the training of the whole network and allow more generalized and effective feature representation. Substantial experiments have been conducted on KITTI and Malaga datasets, and the results demonstrate that our LS-RCNN-VO outperforms the existing learning-based VO approaches.

Design of Midcourse Trajectory for Tactical Ballistic Missile Intercept on the Basis of Zero Effort Miss

2013 ◽  
Vol 397-400 ◽  
pp. 536-545
Author(s):  
Luo Gang Li ◽  
Wu Xing Jing ◽  
Chang Sheng Gao
Keyword(s):  
Relative Motion ◽  
Design Method ◽  
Ballistic Missile ◽  
Prediction Methods ◽  
Trajectory Design ◽  
Motion State ◽  
Simulating Calculation ◽  
Analytical Expressions ◽  
Maximal Principle ◽  
Computing Method

Since the maneuverability of the tactical ballistic missile, the midcourse trajectory of interception missile needs design online. Firstly, this paper reasonably simplifies the models and explores the analytical expressions of their relative motion state to obtain a kind of rapid and high-precision computing method of zero effort miss. Secondly, it applies constant thrust for the interception missile, burns out shut-down solid engine, reflects on the index requirement of overloaded interception missile, and designs midcourse trajectory of the interception missile with Pontryagin maximal principle, in accordance with the analytical expressions of zero effort miss. Finally, with the simulating calculation, the prediction methods of zero effort miss and trajectory design method provided by this paper are applied to a situation simulation which is close to the fact as much as possible so as to verify the applicability in the interception of tactical ballistic missile.

Sign in / Sign up

Export Citation Format

Share Document