New Angular Transmission Design Based on a Four-Bar Linkage Mechanism

2015 ◽  
Author(s):  
Jong-Won Kim ◽  
Jeongae Bak ◽  
TaeWon Seo ◽  
Jongwon Kim
Keyword(s):  
Simulation Analysis ◽  
New Method ◽  
Linkage Mechanism ◽  
Mechanical Loads ◽  
New Device ◽  
Space Efficiency ◽  
Input And Output ◽  
Linkage Design ◽  
Transmission Design ◽  
Four Bar Linkage

This paper presents a new angular transmission device based on a four-bar linkage mechanism. This mechanism consists of a four-bar linkage and an output gear similar to the Geneva drive. When the input link of the four-bar linkage is rotated once, the trajectory of the coupler point is generated. Then, the coupler point drives the motion of the output gear. To rotate the output gear by a specific angle, the design of the four-bar linkage is very important. The mechanism was generated using a new method for four-bar linkage design. Unlike some conventional methods, the new method can consider both the trajectory and the velocity of a coupler point. The new device has two advantages compared to the Geneva drive. Firstly, because the positions of the input and output axes are close to each other, the space efficiency of the new device is higher than that of the Geneva drive. Secondly, the duty factor of the new device is larger than that of the Geneva drive, and the mechanical loads applied to the output gear, such as that from acceleration, are much lower. Kinematic and dynamic simulation analysis was conducted to verify the advantages of the new device.

A New Method for Determining the Effects of Structural Flexibility on the Dynamic Behavior of High Speed Mechanisms

1999 ◽  
Author(s):  
L. Yuan ◽  
J. Rastegar
Keyword(s):  
Dynamic Behavior ◽  
High Speed ◽  
New Method ◽  
Structural Flexibility ◽  
Structural Elements ◽  
Dynamics Modeling ◽  
Linkage Mechanism ◽  
Active Materials ◽  
Response Characteristics ◽  
Four Bar Linkage

Abstract A new method for the analysis of the effects of structural flexibility on the dynamic behavior of mechanical systems is presented. The developed method is in most part based on “tracing” the “propagation” of the effects of the high frequency motion requirements on the dynamic response characteristics of machines with structural flexibilities, particularly those with closed-loop kinematic structures. The method considers the “filtering” action of structural elements with flexibility. Such filtering of higher frequency motions is shown to have a predictable effect on the steady state motion of such mechanical system. The main advantage of the developed method is that the effects of such flexibilities can be determined without the need to perform the usual dynamics modeling and computer simulations. The method is shown to be very simple and readily implementable. The method is applied to a four-bar linkage mechanism with a longitudinally flexible coupler link. The obtained results are shown to be highly accurate as compared to those obtained by computer simulation. The application of the method to systematic design of machines with structural flexibility for high speed and precision operation, optimal integration of smart (active) materials into the structure of such machines, and some related issues are discussed.

Research on Design and Simulation of Four-Bar Linkage Mechanism of Hydraulic Support Based on Virtual Prototype Technology

2012 ◽  
Vol 170-173 ◽  
pp. 3539-3542 ◽  
Author(s):  
Yue Kan Zhang ◽  
Lin Jing Xiao
Keyword(s):  
Simulation Analysis ◽  
Graphical Method ◽  
Motion Path ◽  
Linkage Mechanism ◽  
Hydraulic Support ◽  
Work Requirements ◽  
3D Kinematics ◽  
The Real ◽  
Set Up ◽  
Four Bar Linkage

Four-bar linkage mechanism of the hydraulic support is designed by means of analytical and graphical method. A 3D kinematics model with Pro/E software is set up for the hydraulic support. The simulation analysis and interference of the hydraulic support is carried out and the motion path of the four-bar linkage mechanism under the real project condition is shown. The simulation result shows that the design of the four-bar linkage mechanism is reasonable and the designed hydraulic support meets its actual work requirements.

Planar Linkage Synthesis for Function Generation Using Poles and Rotation Angles

2015 ◽  
Author(s):  
Ronald A. Zimmerman
Keyword(s):  
Analytical Solution ◽  
Graphical Solution ◽  
Function Generation ◽  
Design Time ◽  
Input And Output ◽  
Linkage Design ◽  
Pass Through ◽  
Solution Mechanism ◽  
Four Bar Linkage ◽  
Selection Of

Function Generation is a long standing linkage design problem. It is possible to design a planar four bar linkage whose input and output links will pass through seven coordinated positions. This paper discloses the first graphical solution to this problem. The approach is to consider the constraints imposed by the target positions on the linkage through the poles and rotation angles. This approach enables the designer to explore the range of possible solutions when fewer than seven positions are specified by dragging a fixed or moving pivot in the plane. The selection of free choices is made at the end of the process and the complete mechanism is visible when the choices are made. The constraints only need to be made once which eliminates the repetitive construction required by previous methods to consider multiple pivot locations. Since it is so easy to consider multiple pivot locations and the solution mechanism is visible, the required design time is greatly reduced. A corresponding analytical solution is also developed and solved based on the same constraints. This is a new analytical solution and is defined by a system of 20 nonlinear equations with 20 unknowns.

A Method for Adjustable Planar and Spherical Four-Bar Linkage Synthesis

2004 ◽  
Vol 127 (3) ◽  
pp. 456-463 ◽  
Author(s):  
Boyang Hong ◽  
Arthur G. Erdman
Keyword(s):  
Synthesis Method ◽  
New Method ◽  
Spherical Form ◽  
Numerical Example ◽  
Input And Output ◽  
Special Cases ◽  
Position Synthesis ◽  
Four Bar Linkage ◽  
Linkage Synthesis

This paper describes a new method to synthesize adjustable four-bar linkages, both in planar and spherical form. This method uses fixed ground pivots and an adjustable length for input and output links. A new application of Burmester curves for adjustable linkages is introduced, and a numerical example is discussed. This paper also compares a conventional synthesis method (nonadjustable linkage) to the new method. Nonadjustable four-bar linkages provide limited solutions for five-position synthesis. Adjustable linkages generate one infinity of solution choices. This paper also shows that the nonadjustable solutions are special cases of adjustable solutions. This new method can be extended to six position synthesis, with adjustable ground pivots locations.

ON THE HYBRID-DRIVEN LINKAGE MECHANISM WITH ONE INPUT CYCLE CORRESPONDING TO TWO OUTPUT CYCLES

2015 ◽  
Vol 39 (3) ◽  
pp. 637-646
Author(s):  
Ren-Chung Soong
Keyword(s):  
Kinematic Analysis ◽  
Angular Speed ◽  
Motion Trajectory ◽  
Dimensional Synthesis ◽  
Reciprocating Motion ◽  
Linkage Mechanism ◽  
Output Link ◽  
Input And Output ◽  
Single Input ◽  
Selection Of

A hybrid-driven five-bar linkage mechanism with one input cycle corresponding to two output cycles is presented. The proposed linkage mechanism is driven by a constant-speed motor and a linear motor, respectively. The output link can generate two same required output cycles during a single input cycle, while the rotational input link rotates with a constant angular speed, and the linear input link follows a reciprocating motion along a specified linear guide fixed on the rotational input link. The configuration, displacement relationship between the input and output links, and conditions of mobility of this proposed mechanism were studied, and a kinematic analysis was performed. The selection of the instantaneous motion trajectory of the linear input link and an optimal dimensional synthesis are also described. An example is provided to verify the feasibility and effectiveness of this methodology.

Optimal Control of a Flexible Mechanism Using a Combined Feedforward-Feedback Strategy: Simulation and Experiment

1999 ◽  
Author(s):  
Hubertus v. Stein ◽  
Heinz Ulbrich
Keyword(s):  
Optimal Control ◽  
Control Strategy ◽  
System Performance ◽  
High Speed ◽  
Time Varying ◽  
Linkage Mechanism ◽  
Additional Degree ◽  
Control Approach ◽  
Feedback Optimal Control ◽  
Four Bar Linkage

Abstract Due to the elasticity of the links in modern high speed mechanisms, increasing operating speeds often lead to undesirable vibrations, which may render a required accuracy unattainable or, even worse, lead to a failure of the whole process. The dynamic effects e.g. may lead to intolerable deviations from the reference path or even to the instability of the system. Instead of suppressing the vibration by a stiffer design, active control methods may greatly improve the system performance and lead the way to a reduction of the mechanism’s weight. We investigate a four-bar-linkage mechanism and show that by introducing an additional degree of freedom for a controlled actuator and providing a suitable control strategy, the dynamically induced inaccuracies can be substantially reduced. The modelling of the four-bar-linkage mechanism as a hybrid multi body system and the modelling of the complete system (including the actuator) is briefly explained. From the combined feedforward-feedback optimal control approach presented in (v. Stein, Ulbrich, 1998) a time-varying output control law is derived that leads to a very good system performance for this linear discrete time-varying system. The experimental results show the effectiveness of the applied control strategy.

A New Method of Torque Compensation for High Speed Indexing Cam Mechanism

1999 ◽  
Vol 121 (2) ◽  
pp. 319-323 ◽  
Author(s):  
Teng Guilan ◽  
Fu Haibo ◽  
Zhou Weiyi
Keyword(s):  
Kinetic Energy ◽  
High Speed ◽  
Output Shaft ◽  
New Method ◽  
Linkage Mechanism ◽  
Energy Fluctuation ◽  
Positioning Accuracy ◽  
Input Shaft ◽  
Cam Mechanism

Severe vibration and poor positioning accuracy may occur in an indexing cam mechanism operating at a high speed. Torque fluctuation of the input shaft and the resulting fluctuation of kinetic energy of the mechanism may be the major cause of the vibration. In this paper a method is proposed to minimize the fluctuation by using a so-called “speed-varying flywheel” that produces an opposite kinetic energy fluctuation that can counteract the effect of the energy fluctuation. The flywheel is installed on the output shaft of an additional cam-linkage mechanism. The parameter of the cam-linkage mechanism is optimized. An example is given to demonstrate the effectiveness of this method.

scholarly journals Feeding mechanics and bite force modelling of the skull of Dunkleosteus terrelli , an ancient apex predator

2006 ◽  
Vol 3 (1) ◽  
pp. 77-80 ◽  
Author(s):  
Philip S.L Anderson ◽  
Mark W Westneat
Keyword(s):  
High Speed ◽  
Prey Capture ◽  
Mouth Opening ◽  
Biomechanical Model ◽  
Bite Force ◽  
Rapid Expansion ◽  
Large Individual ◽  
Linkage Mechanism ◽  
Feeding Mechanics ◽  
Four Bar Linkage

Placoderms are a diverse group of armoured fishes that dominated the aquatic ecosystems of the Devonian Period, 415–360 million years ago. The bladed jaws of predators such as Dunkleosteus suggest that these animals were the first vertebrates to use rapid mouth opening and a powerful bite to capture and fragment evasive prey items prior to ingestion. Here, we develop a biomechanical model of force and motion during feeding in Dunkleosteus terrelli that reveals a highly kinetic skull driven by a unique four-bar linkage mechanism. The linkage system has a high-speed transmission for jaw opening, producing a rapid expansion phase similar to modern fishes that use suction during prey capture. Jaw closing muscles power an extraordinarily strong bite, with an estimated maximal bite force of over 4400 N at the jaw tip and more than 5300 N at the rear dental plates, for a large individual (6 m in total length). This bite force capability is the greatest of all living or fossil fishes and is among the most powerful bites in animals.

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