Dynamic Analysis and Simulation for Bionic Power-Assisted Legs of Hill Area Agricultural Machinery

2013 ◽  
Vol 675 ◽  
pp. 107-110
Author(s):  
Ke Dong Zhou ◽  
Jin Ge Wang ◽  
Jun Min Li ◽  
Jiang Mei Liao
Keyword(s):  
Dynamic Analysis ◽  
Intelligent Control ◽  
Driving Force ◽  
Design Principle ◽  
Inverse Dynamics ◽  
Hydraulic Cylinder ◽  
Structure Design ◽  
Agricultural Machinery ◽  
Hill Area ◽  
Dynamics Problems

According to a series of hill area issues, such as big steep gradients, small and disperse plots, agricultural machinery climbing restriction and so on, a new 2-DOF bionic power-assisted legs mechanism driven by hydraulic is proposed. This paper states the design principle of the bionic legs mechanism and its application in agricultural machinery. A dynamic model is used to show how the hind leg assisted agricultural machinery is established, and then deduce the dynamics equation, and solve the inverse dynamics problems. The result shows that agricultural machinery movement along slope is steady with the help of the hind leg, and driving force of hydraulic cylinder changes is slightly without any distinct impact to other devices, the actuated project is feasible and the structure design is reasonable, and it can be used to research on intelligent control of bionic legs and hill area agricultural machinery.

Dynamic Analysis on a Cable-Driven Interventional Active Catheter Using Kane's Method Combined with Screw Theory

2014 ◽  
Vol 527 ◽  
pp. 140-145
Author(s):  
Da Xu Zhao ◽  
Bai Chen ◽  
Guo Zhong Shou ◽  
Yu Qi Gu
Keyword(s):  
Mathematical Model ◽  
Dynamic Analysis ◽  
Motion Control ◽  
Screw Theory ◽  
Driving Forces ◽  
Structure Design ◽  
Kinematics And Dynamics ◽  
Existing Problems ◽  
Blind Area ◽  
The Mathematical Model

In view of the existing problems of traditional interventional catheters, particularly poor activity, operation difficulty and mass blind area, a novel interventional catheter with a cable-driven active head-end is proposed, and a prototype was built to verify the performance. This paper deals with the kinematics and dynamics of the cable-driven prototype, a dynamic model based on Kanes method combined with screw theory was presented in this paper. According the mathematical model and the prototypes structure, the analysis of kinematics and dynamics of active head-end-end is done in the environment of Mathematica. The needed driving forces of every joint when the system moving along planned trajectory are calculated. The results can provide a basis for the structure design and motion control of the interventional active catheter.

Experimental Validation of a Dynamic Simulation

1990 ◽  
Author(s):  
K. Harold Yae ◽  
Su-Tai Chern ◽  
Howyoung Hwang
Keyword(s):  
Dynamic Analysis ◽  
Dynamic Simulation ◽  
Time Domain ◽  
Experimental Validation ◽  
Initial Conditions ◽  
Hydraulic Cylinder ◽  
Force Output ◽  
Inverse Dynamic ◽  
Inverse Dynamic Analysis ◽  
The Time Domain

Abstract Using forward and inverse dynamic analysis, the dynamic simulation of a backhoe has been compared with experiments. In the experiment, recorded were the configuration and force histories; that is, velocity and position, and force output from the hydraulic cylinder-all were measured in the time domain. When the experimental force history is used as driving force in the simulation, forward dynamic analysis produces a corresponding motion history. And when the experimental motion history is used as if a prescribed trajectory, inverse dynamic analysis generates a corresponding force history. Therefore, these two sets of motion and force histories — one set from experiment, and the other from the simulation that is driven forward and backward with the experimental data — are compared in the time domain. The comparisons are discussed in regard to the effects of variations in initial conditions, friction, and viscous damping.

Design and Manufacturing of Cylinder-Beam Integrated Hydraulic Press

2013 ◽  
Vol 397-400 ◽  
pp. 157-161
Author(s):  
Wei Wei Zhang ◽  
Xiao Song Wang ◽  
Shi Jian Yuan ◽  
Zhong Ren Wang
Keyword(s):  
Driving Force ◽  
Geometric Dimension ◽  
Hydraulic Cylinder ◽  
Hydraulic Press ◽  
Force Distribution ◽  
Section Modulus ◽  
The Press ◽  
The World ◽  
Design And Manufacturing ◽  
Institute Of Technology

For a cylinder-beam integrated hydraulic press (CBIHP), the hydraulic cylinder is also functioned as an upper beam. It is the key structural component that outputs the driving force to forge parts. Compared with the traditional three-beam and four-column hydraulic press which has a cylindrical hydraulic cylinder, the structure and force distribution are significantly different for CBIHP. It is able to have higher nominal force and larger section of plunger which the pressure is applied on when the contour geometric dimension is the same. Also, CBIHP has lighter weight and larger section modulus when the nominal force is the same than the traditional hydraulic press. Finally, a 6300KN cylinder-beam integrated hydraulic press, which is the first CBIHP in the world and designed by Harbin Institute of Technology (HIT) in 2012, is also introduced in this paper. It can be seen from the results of numerical simulation for the CBIHP that both of the stresses and displacements on the press in the loading process are allowable.

Inverse Dynamic Analysis and Linearisation of a High Speed Parallel Mechanism

2005 ◽  
Author(s):  
M. Necip Sahinkaya ◽  
Yanzhi Li
Keyword(s):  
Dynamic Analysis ◽  
Parallel Mechanism ◽  
High Speed ◽  
Inverse Dynamics ◽  
Motion Path ◽  
Model Parameters ◽  
Control Input ◽  
Inverse Dynamic ◽  
Inverse Dynamic Analysis ◽  
Dynamics Models

Inverse dynamic analysis of a three degree of freedom parallel mechanism driven by three electrical motors is carried out to study the effect of motion speed on the system dynamics and control input requirements. Availability of inverse dynamics models offer many advantages, but controllers based on real-time inverse dynamic simulations are not practical for many applications due to computational limitations. An off-line linearisation of system and error dynamics based on the inverse dynamic analysis is developed. It is shown that accurate linear models can be obtained even at high motion speeds eliminating the need to use computationally intensive inverse dynamics models. A point-to-point motion path for the mechanism platform is formulated by using a third order exponential function. It is shown that the linearised model parameters vary significantly at high motion speeds, hence it is necessary to use adaptive controllers for high performance.

scholarly journals Structure design and reliability analysis of Al-Ti lugs

2021 ◽  
Vol 39 (1) ◽  
pp. 1-8
Author(s):  
Yunwen Feng ◽  
Jiale Zhang ◽  
Xiaofeng Xue ◽  
Xiaoping Zhong ◽  
Wei Xie
Keyword(s):  
Reliability Analysis ◽  
Structural Design ◽  
Design Principle ◽  
Load Transfer ◽  
Design Method ◽  
Static Strength ◽  
Structure Design ◽  
Safety Design ◽  
Design Requirements ◽  
Metal Materials

Aircraft lug joint is the key part of load transfer. In order to improve the safety of lug joint, on the premise of meeting the design requirements of static strength and fatigue, the composite connection lug structure design technology of different metal materials is proposed in this paper. Firstly, the damage safety design and life reliability analysis of the lug structure are studied theoretically. Secondly, based on the concept of damage safety design and the design principle of deformation coordination, the design method of composite connection lug with deformation coordination is proposed, and the thickness ratio of single ear is 0.8:1:0.8. Finally, the reliability of the composite lug is analyzed. The results show that the structural design scheme of aluminum-titanium composite ear piece can meet the requirements of static strength and damage tolerance, and compared with the conventional ear structure, the failure probability of structure mission life is greatly reduced when the weight of the composite connection lug is only increased by 4.9%. The proposed method can effectively guide the structural design of composite ear piece.

scholarly journals A Novel Capacitive Sensing Principle for Microdevices

2015 ◽  
Author(s):  
Jian Zhou ◽  
Ronald N. Miles ◽  
Shahrzad Towfighian
Keyword(s):  
Electric Field ◽  
Driving Force ◽  
Design Principle ◽  
Electrostatic Force ◽  
Low Cost ◽  
Repulsive Force ◽  
Attractive Force ◽  
Sensor Design ◽  
Capacitive Sensing

Conventional capacitive sensing places significant limitations on the sensor design due to the pull-in instability caused by the electrostatic force. The main purpose of this study is to examine a low-cost novel capacitive sensing principle based on electrostatic balance which promises to avoid these design limitations. The approach uses an asymmetric electric field on a structure with fingers that can generate a repulsive force while the gap is low and create an attractive force while the gap is large. The size and thickness of the fingers are also responsible for creating repulsive or attractive forces on the structure. This approach has recently been applied successfully in the design of capacitive actuators to provide a repulsive driving force. A new design principle for capacitive sensing is described that avoids pull-in instability by designing the fingers such that the structure is at the equilibrium.

Analysis of Hybrid Programming Simulation Based on the Variable Stiffness Ring With Expanding Loop SMA Actuator

2017 ◽  
Author(s):  
Lei Wang ◽  
Zong-quan Deng ◽  
Hao-di Wang ◽  
Hong-hao Yue
Keyword(s):  
Thermal Stress ◽  
Elastic Modulus ◽  
Active Control ◽  
Driving Force ◽  
Structure Design ◽  
Smart Structure ◽  
Space Craft ◽  
Stiffness Variation ◽  
Sma Actuator ◽  
Driving Source

In the development of space craft design index, the requirements of hypersonic space craft control accuracy has been increasingly rigorous. Thin-walled structure is often employed in hypersonic craft to reduce the weight of the load and to save the room. During the flight of the craft, temperature field is produced along the surface and the dynamic properties of the craft structure are obviously changed. The decreasing elastic modulus of the structure material and the appearance of thermal stress lead to the decrease of integral rigidity and stability of the structure, then the thermal flutter appears and control difficulties increase. Shape Memory Alloy (SMA) has the advantages of the considerable driving force in the compact volume and the simple driving method. By the combination of actuator structure design and stiffness control, the smart structure is able to make active control to the thermal stiffness variation. In this paper, the apex high-temperature area is equivalent to a ring structure. Finite difference method is employed firstly to transform the governing partial differential equation into discrete finite difference equations. Then the elastic modulus change, thermal stress and tension along the circumference are considered comprehensively to propose the calculation formulas of equivalent young’s modulus. The discrete dynamic matrix model is obtained containing the control terms of SMA. To solve the big-matrix calculation and multiple iterated large data problem, hybrid program is developed with C++ and MATLAB. Finite element software is employed to make optimization analysis to design an expanding loop actuator containing SMA as driving source, variable thickness loops of spring steel as expanding units, and universal-ball pre-loading units. On the basis of that, the thermal stiffness variation active control system with smart structure is developed based on expanding loop SMA actuator. After the analysis of examples, the variation law of the needed SMA driving force is obtained. The distribution position and quantity of the driving source is optimized. This research provides reference for the Theoretical Analysis and Simulation of structure stiffness active control and adaptive control of the aircraft employing smart material. The research results have guiding significance for the smart structure design of hypersonic aircraft in the future.

The Research and Application on Optimization Design of Lifting Mechanism - The Hydraulic Cylinder Structure Design

2014 ◽  
Vol 945-949 ◽  
pp. 503-508
Author(s):  
Li Xie ◽  
Qi Sun
Keyword(s):  
Optimization Design ◽  
Lower Cost ◽  
Hydraulic Cylinder ◽  
Structure Design ◽  
Optimal Parameters ◽  
Modern Computer ◽  
Optimal Value ◽  
Design Cycle ◽  
General Mechanic ◽  
Modern Computer Technology

As general mechanic designing methods take long design cycle and consume many resources, though it could find a good design, it could not get the optimal one.Optimization design is the fruit of the combination of optimization mathematical method and modern computer technology, which enables to get the optimal parameters under various constrains, so that the optimal value could be achieved. Optimization design is a method to ensure better usability, lower cost and reducing weight and volume when normally use it. This method can also shorten the design cycle and enhance the design efficiency.

Dynamic Analysis on the Principle and General Research Situation of Band Conveyor

2014 ◽  
Vol 525 ◽  
pp. 210-213
Author(s):  
Mei Wang
Keyword(s):  
Dynamic Analysis ◽  
Design Principle ◽  
Belt Conveyor ◽  
Analysis Software ◽  
The Status ◽  
Status Analysis ◽  
Research Situation

The process of large belt conveyor operation must be more accurate by using dynamic analysis. Dynamic analysis and complex, not easy to grasp, needanalysis software -- conveyor dynamic analysis. Based on the status analysis of the domestic belt conveyor dynamic, about software overview of belt conveyor dynamic analysis, the design principle and the belt conveyor dynamic, analysis and applicationof dynamic analysis software.

Sign in / Sign up

Export Citation Format

Share Document