Analysis and Design of a Four-Bar Linkage Type of Vibratory Parts Feeder Driven by Piezoelectric Actuator

2002 ◽  
Author(s):  
Yung Ting ◽  
Min-Sheng Shin ◽  
Hong-Yuan Chang
Keyword(s):  
Dynamic Modeling ◽  
Piezoelectric Actuator ◽  
Good Accuracy ◽  
Experimental Result ◽  
Linkage Mechanism ◽  
Analysis And Design ◽  
Output Performance ◽  
Feedback Design ◽  
Analytical Result ◽  
Four Bar Linkage

In this article, vibratory parts feeder widely used in industrial automation with the structure of a symmetric four-bar linkage mechanism driven by piezoelectric actuator is investigated. The dynamic modeling and simulation of the system as well as the driving controller are developed. Experiment is carried out to measure the practical acceleration and force of the vibratory platform. In comparison the experimental result with the analytical result, both outcomes are quite matched, which indicates their good accuracy. Driving control circuitry with feedback design is instrumental to provide steady output performance. Finally, optimum design to improve the transport speed and keep the parts in order is discussed.

scholarly journals Design and Implementation of a Lizard-Inspired Robot

2021 ◽  
Vol 11 (17) ◽  
pp. 7898
Author(s):  
Shunsuke Nansai ◽  
Yuki Ando ◽  
Hiroshi Itoh ◽  
Norihiro Kamamichi
Keyword(s):  
Kinematic Analysis ◽  
Stride Length ◽  
Longitudinal Direction ◽  
Experimental Result ◽  
Linkage Mechanism ◽  
Turning Angle ◽  
Design And Implementation ◽  
The Third ◽  
Kinematic Analyses ◽  
Four Bar Linkage

The purpose of this paper is to design a lizard-inspired robot driven by a single actuator. Lizard-inspired robots in previous studies had the issue of slippage of their supporting legs. To overcome this issue, a lizard-inspired robot consisting of a four-bar linkage mechanism was designed. The purpose of this paper was achieved through three processes. The first process was kinematic analysis, where the turning angle and stride length of the robot were analyzed. The kinematic analysis results were verified via numerical simulations. The second process was the design and fabrication of the robot. For the robot’s design, both a shuffle-walking method utilizing a claw-shaped leg mechanism and a sliding-rod mechanism for equipping the actuator on the robot’s own coordinates were designed. The third process was experimental verification. The first experimental result was that the claw-shaped leg mechanism was capable of generating an 85.26 N difference in the static frictional force in the longitudinal direction. The other three experimental results were that the robot was capable of driving with 3.51%, 3.16%, and 3.53% error compared to the kinematic analyses, respectively.

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.

Hydrodynamics modeling of a piezoelectric micro-robotic fish with double caudal fins

2021 ◽  
pp. 1-24
Author(s):  
Quan-Liang Zhao ◽  
Jinghao Chen ◽  
Hongkuan Zhang ◽  
Zhonghai Zhang ◽  
Zhikai Liu ◽  
...  
Keyword(s):  
Piezoelectric Actuator ◽  
Robotic Fish ◽  
Caudal Fin ◽  
Four Bar Linkage ◽  
Kinetics Of ◽  
Blade Element

Abstract An analytical hydrodynamics model for a piezoelectric micro-robotic fish with double caudal fins is presented in this paper. The relation between displacement of the piezoelectric actuator and oscillating angle of the caudal fin is established based on the analysis of the flexible four-bar linkage transmission. The hydrodynamics of caudal fins are described by airfoil and blade element theories. Furthermore, the dynamics and kinetics of the whole micro-robotic fish are analyzed and validated by experiments.

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.

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.

KINETOSTATIC ANALYSIS FOR FOUR-BAR LINKAGE MECHANISM OF PROSTHETIC KNEE JOINT

2019 ◽  
Vol 19 (04) ◽  
pp. 1950018 ◽  
Author(s):  
XUHUI LIU ◽  
TIANTIAN GUO ◽  
JIAHAO ZHANG ◽  
GUANG YANG ◽  
LUCHAN SUN ◽  
...  
Keyword(s):  
Knee Joint ◽  
Group Method ◽  
Linkage Mechanism ◽  
Analysis Software ◽  
Prosthetic Knee ◽  
Damping Effect ◽  
D’Alembert Principle ◽  
Prosthetic Knee Joint ◽  
Four Bar Linkage ◽  
The Relationship

In this paper, a mathematical model of four-bar linkage mechanism is built to investigate the prosthetic knee joint, by means of the bar group method, and the motion of the prosthetic knee joint is simulated by motion analysis software. In the state of motion of the four linkage mechanism, to the moving component of the mechanism, the relationship between the moving displacement, velocity and acceleration are obtained. On the basis of the above investigation, dynamic statics analysis for the moving component of four-bar linkage mechanism are completed by the ‘D’Alembert principle. The research results show that, with the change of the rotating angle of the active part, the counter-force of rotating pair and the balance torque on active component are all changeable, which will provide a theoretical basis for the design of prosthetic knee joint mechanism with longer life and better damping effect.

Active Vibration Control for the Closed Loop Flexible Mechanisms Combined the Feedback and Feed-Forward Strategy: Part 2 — Control Design and Simulation

2000 ◽  
Author(s):  
Zhang Xianmin ◽  
Chao Changjian
Keyword(s):  
Equations Of Motion ◽  
Active Vibration Control ◽  
Elastic Vibration ◽  
Linkage Mechanism ◽  
Control Laws ◽  
Feed Forward ◽  
Feed Forward Control ◽  
Active Vibration ◽  
Four Bar Linkage ◽  
Flexible Mechanisms

Abstract On the basis of the complex mode theory and the equations of motion of the flexible mechanisms developed in part 1, a hybrid independent modal controller is presented, which is composed of state feedback and disturbance feed-forward control laws. As an illustrative example, the strategy is used to control the elastic vibration response of a four-bar linkage mechanism. The imitative computational result shows that the vibration is efficiently suppressed.

scholarly journals An investigation of various actuation mechanisms in robot arm

2019 ◽  
Vol 52 (9-10) ◽  
pp. 1299-1307 ◽  
Author(s):  
J Prakash ◽  
M Ilangkumaran
Keyword(s):  
Analytical Approach ◽  
Robot Arm ◽  
Force Analysis ◽  
Linkage Mechanism ◽  
Actuation Mechanism ◽  
Research Activities ◽  
Grasping Force ◽  
Object Shapes ◽  
End Effectors ◽  
Four Bar Linkage

Many research activities have been carried out to develop a simple mechanism for grasping irregular object shapes using two- or three-fingered robot end effectors. The idea behind this work is to develop three-fingered intelligent grippers that are capable of sensing different factors like weight, effort required, compactness, robustness, and stability of the object held during the manipulations. In this paper, five different actuation mechanisms, namely, edge-cam-operated actuation mechanism, toggle-linkage-based actuation mechanism, wedge-cam-operated gripper, sliding slotted pin–ball joint arrangement, and rack-and-pinion-operated four-bar linkage mechanism, are introduced. The actuation and grasping force of the gripper are to be determined using the analytical approach (static force analysis). Finally, the effective intelligent gripper mechanism is identified based on grasping force for grasping 1 kg weight of a prespecified object.

Sign in / Sign up

Export Citation Format

Share Document