ON THE POSSIBILITY OF THE POSTTRANSITION STATE CLASSICAL TRAJECTORY PREDICTIONS OF ENERGY DEPOSITION IN THE REACTION PRODUCTS' DEGREES OF FREEDOM

2020 ◽  
Author(s):  
B. I. Loukhovitski ◽  
◽  
A. S. Sharipov ◽  
Keyword(s):  
Energy Distribution ◽  
Degrees Of Freedom ◽  
Energy Deposition ◽  
Classical Trajectory ◽  
Reaction Products ◽  
Dynamic Simulations ◽  
Bimolecular Reactions

The possibility of applying the method of posttransition state classical trajectory dynamic simulations to study the nascent energy distribution among the molecular degrees of freedom of the reaction products on the example of a number of bimolecular reactions is considered.

Energy distribution among reaction products. H + NOCl, H + ICl

1974 ◽  
Vol 29 (4) ◽  
pp. 473-479 ◽  
Author(s):  
M.A. Nazar ◽  
J.C. Polanyi ◽  
W.J. Skrlac
Keyword(s):  
Energy Distribution ◽  
Reaction Products

Estimation of Nanometer-Sized EB Patterning Using Energy Deposition Distribution in Monte Carlo Simulation

2011 ◽  
Vol 497 ◽  
pp. 127-132 ◽  
Author(s):  
Hui Zhang ◽  
Takuro Tamura ◽  
You Yin ◽  
Sumio Hosaka
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Electron Beam ◽  
Energy Distribution ◽  
Electron Energy ◽  
Electron Beam Lithography ◽  
Energy Deposition ◽  
Si Substrate ◽  
Positive Resist

We have studied on theoretical electron energy deposition in thin resist layer on Si substrate for electron beam lithography. We made Monte Carlo simulation to calculate the energy distribution and to consider formation of nanometer sized pattern regarding electron energy, resist thickness and resist type. The energy distribution in 100 nm-thick resist on Si substrate were calculated for small pattern. The calculations show that 4 nm-wide pattern will be formed when resist thickness is less than 30 nm. Furthermore, a negative resist is more suitable than positive resist by the estimation of a shape of the energy distribution.

scholarly journals Jumping in frogs: assessing the design of the skeletal system by anatomically realistic modeling and forward dynamic simulation

2002 ◽  
Vol 205 (12) ◽  
pp. 1683-1702 ◽  
Author(s):  
William J. Kargo ◽  
Frank Nelson ◽  
Lawrence C. Rome
Keyword(s):  
Degrees Of Freedom ◽  
The Body ◽  
Joint Torque ◽  
Rotational Degree ◽  
Skeletal System ◽  
Dynamic Simulations ◽  
Inverse Dynamic ◽  
Maximal Distance ◽  
Out Of Plane ◽  
Rotational Degrees Of Freedom

SUMMARY Comparative musculoskeletal modeling represents a tool to understand better how motor system parameters are fine-tuned for specific behaviors. Frog jumping is a behavior in which the physical properties of the body and musculotendon actuators may have evolved specifically to extend the limits of performance. Little is known about how the joints of the frog contribute to and limit jumping performance. To address these issues, we developed a skeletal model of the frog Rana pipiens that contained realistic bones, joints and body-segment properties. We performed forward dynamic simulations of jumping to determine the minimal number of joint degrees of freedom required to produce maximal-distance jumps and to produce jumps of varied take-off angles. The forward dynamics of the models was driven with joint torque patterns determined from inverse dynamic analysis of jumping in experimental frogs. When the joints were constrained to rotate in the extension—flexion plane, the simulations produced short jumps with a fixed angle of take-off. We found that, to produce maximal-distance jumping,the skeletal system of the frog must minimally include a gimbal joint at the hip (three rotational degrees of freedom), a universal Hooke's joint at the knee (two rotational degrees of freedom) and pin joints at the ankle,tarsometatarsal, metatarsophalangeal and iliosacral joints (one rotational degree of freedom). One of the knee degrees of freedom represented a unique kinematic mechanism (internal rotation about the long axis of the tibiofibula)and played a crucial role in bringing the feet under the body so that maximal jump distances could be attained. Finally, the out-of-plane degrees of freedom were found to be essential to enable the frog to alter the angle of take-off and thereby permit flexible neuromotor control. The results of this study form a foundation upon which additional model subsystems (e.g. musculotendon and neural) can be added to test the integrative action of the neuromusculoskeletal system during frog jumping.

SUB-keV ATOM INDUCED SPUTTERING OF CONDENSED N2: A MOLECULAR DYNAMICS STUDY

1993 ◽  
Vol 07 (13n14) ◽  
pp. 857-863 ◽  
Author(s):  
HEINO KAFEMANN ◽  
HERBERT M. URBASSEK
Keyword(s):  
Molecular Dynamics ◽  
Energy Distribution ◽  
Time Dependence ◽  
Degrees Of Freedom ◽  
Center Of Mass ◽  
Translational Motion ◽  
Original Position ◽  
Time And Space

By molecular dynamics, the sputtering of a condensed N 2 sample due to 100 eV N atom bombardment is studied. The features observed in general parallel those of previous studies of Ar sputtering. Time- and space-resolved measurements give novel information on the original position of sputtered molecules and the time dependence of their energy distribution. Rotational and vibrational degrees of freedom are underpopulated with respect to center-of-mass translational motion.

Using a Redundant Planar Hip Exoskeleton to Reduce Human-Device Interface Forces

2017 ◽  
Author(s):  
David Schmitthenner ◽  
Samuel H. Shoemaker ◽  
Anne E. Martin
Keyword(s):  
Soft Tissue ◽  
Hip Joint ◽  
Degrees Of Freedom ◽  
Shear Forces ◽  
Dynamic Simulations ◽  
Lower Shear ◽  
Human Soft Tissue ◽  
Priority Method ◽  
Joint Center ◽  
Human Device

Robotic exoskeletons have the potential to improve gait rehabilitation. Currently, most exoskeletons use revolute joints that must be exactly aligned with the user’s joints to prevent uncomfortable shear forces at the human-device interface. This paper presents an alternative design for a planar hip exoskeleton based on a planar Stewart platform. In theory, this mechanism does not require exact knowledge of the human hip joint center of rotation to prevent large shear forces. The total human-device system has four degrees of freedom if the human soft tissue is neglected, which does complicate the control of the system compared to a rotational exoskeleton. To find a mapping between the desired human hip angle and the four actuated joints, the task priority method is used. To determine how well the proposed device can guide the hip through a step, dynamic simulations were conducted and compared to the results for a rotational exoskeleton. The compliance in the human soft tissue was included in the simulations because it can play a significant role in both the motion of the system and the human-device forces. Both the ideal case of exact hip joint alignment and the more likely case of hip joint misalignment were considered. In addition, the effects of differing levels of human effort were compared. In all cases, both exoskeletons were well able to guide the human hip in the desired motion. In addition, the novel exoskeleton has significantly lower shear forces at the thigh human-device connection point.

Design and locomotion analysis of a novel deformable mobile robot with two spatial reconfigurable platforms and three kinematic chains

2016 ◽  
Vol 231 (8) ◽  
pp. 1481-1499 ◽  
Author(s):  
Wan Ding ◽  
Qiang Ruan ◽  
Yan-an Yao
Keyword(s):  
Mobile Robot ◽  
Degrees Of Freedom ◽  
Three Dimensional ◽  
Three Dimensional Model ◽  
Dynamic Simulations ◽  
Gait Planning ◽  
Plane Symmetric ◽  
Kinematic Chains ◽  
Reconfigurable Platforms ◽  
Actuation Systems

A novel five degrees of freedom deformable mobile robot composed of two spatial reconfigurable platforms and three revolute–prismatic–spherical kinematic chains acting in parallel to link the two platforms is proposed to realize large deformation capabilities and multiple locomotion modes. Each platform is an improved deployable single degrees of freedom three-plane-symmetric Bricard linkage. By taking advantage of locomotion collaborating among platforms and kinematic chains, the mobile robot can fold into stick-like shape and possess omnidirectional rolling and worm-like motions. The mechanism design, kinematics, and locomotion feasibility are the main focus. Through kinematics and gait planning, the robot is analyzed to have the capabilities of rolling and turning. Based on its deformation, the worm-like motion performs the ability to overcome narrow passages (such as pipes, holes, gaps, etc.) with large range of variable size. Dynamic simulations with detailed three-dimensional model are carried out to verify the gait planning and provide the variations of essential motion and dynamic parameters in each mode. An experimental robotic system with servo and pneumatic actuation systems is built, experiments are carried out to verify the validity of the theoretical analysis and the feasibility of the different locomotion functions, and its motion performances are compared and analyzed with collected data.

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