Dynamics Analysis of planetary Gear Train with Two Degrees of Freedom

Dynamic Characteristics of Double Helical Planetary Gear Train With Tooth Friction

Volume 10: ASME 2015 Power Transmission and Gearing Conference; 23rd Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2015-48022 ◽

2015 ◽

Cited By ~ 1

Author(s):

Fengxia Lu ◽

Rupeng Zhu ◽

Haofei Wang ◽

Heyun Bao ◽

Miaomiao Li

Keyword(s):

Degrees Of Freedom ◽

Sliding Friction ◽

Planetary Gear ◽

Gear Train ◽

Variable Step Size ◽

Step Size ◽

Planetary Gear Train ◽

Gear Mesh ◽

Meshing Stiffness ◽

Nonlinear Dynamics Model

A new nonlinear dynamics model of the double helical planetary gear train with 44 degrees of freedom is developed, and the coupling effects of the sliding friction, time-varying meshing stiffness, gear backlashes, axial stagger as well as gear mesh errors, are taken into consideration. The solution of the differential governing equation of motion is solved by variable step-size Runge-Kutta numerical integration method. The influence of tooth friction on the periodic vibration and nonlinear vibration are investigated. The results show that tooth friction makes the system motion become stable by the effects of the periodic attractor under the specific meshing frequency and leads to the frequency delay for the bifurcation behavior and jump phenomenon in the system.

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Conceptual Design of Gear Differentials for Automotive Vehicles

Journal of Mechanical Design ◽

10.1115/1.2919415 ◽

1994 ◽

Vol 116 (2) ◽

pp. 565-570 ◽

Cited By ~ 16

Author(s):

Hong-Sen Yan ◽

Long-Chang Hsieh

Keyword(s):

Conceptual Design ◽

Degrees Of Freedom ◽

Planetary Gear ◽

Gear Train ◽

Design Constraints ◽

Two Degrees Of Freedom ◽

Design Concepts ◽

Planetary Gear Trains ◽

Gear Trains ◽

Gear Differential

An automotive gear differential is a joint-fractionated planetary gear train with two degrees-of-freedom. We summarize the characteristics of planetary gear trains and the design constraints of noncoupled automotive gear differentials to synthesize their corresponding kinematic graphs. Based on these graphs and the proposed respecializing process, we generate the atlas of design concepts for automotive gear differentials with any types of gear pairs. As a result, there are 4, 25, and 156 design concepts for five-, six-, and seven-bar automotive gear differentials, respectively.

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EMBODIMENT DESIGN OF NOVEL 5-SPEED REAR DRIVE HUBS FOR BICYCLES

Transactions of the Canadian Society for Mechanical Engineering ◽

10.1139/tcsme-2015-0032 ◽

2015 ◽

Vol 39 (3) ◽

pp. 431-441 ◽

Cited By ~ 1

Author(s):

Yi-Chang Wu ◽

Tze-Cheng Wu

Keyword(s):

Power Flow ◽

Degrees Of Freedom ◽

Planetary Gear ◽

Gear Train ◽

Main Body ◽

Direct Drive ◽

Drive Gear ◽

Planetary Gear Train ◽

Embodiment Design ◽

The Relationship

This paper presents embodiment design of 5-speed rear drive hubs for bicycles. A 7-link, 2-degrees of freedom (DOF) compound planetary gear train as the main body of a rear drive hub is introduced. The relationship between the number of coaxial links of a planetary gear train and the number of gear stages that a drive hub can provide with is discussed. By means of kinematic analysis, four speed ratios of the planetary gear train are derived, which represents four forward gears of the rear drive hub. By adding a direct-drive gear, five forward gears can be provided and two feasible clutching sequence tables are synthesized. Manual translational-type gear-shifting mechanisms are further designed to incorporate with the planetary gear train for appropriately controlling the gear stage. The power-flow path at each gear stage is checked to verify the feasibility of the proposed design. Finally, two novel 5-speed bicycle rear drive hubs are presented.

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Work of the planetary gear trains as differentials and their capabilities

MATEC Web of Conferences ◽

10.1051/matecconf/201928704001 ◽

2019 ◽

Vol 287 ◽

pp. 04001

Author(s):

Kiril Arnaudov ◽

Stefan Petrov ◽

Emiliyan Hristov

Keyword(s):

Degrees Of Freedom ◽

Planetary Gear ◽

Gear Ratio ◽

Gear Train ◽

Motor Drive ◽

Planetary Gear Train ◽

Maximum Security ◽

Single Carrier ◽

Planetary Gear Trains ◽

Gear Trains

Planetary gear trains can work differently, namely, with F=1 degree of freedom, i.e. as reducers or multipliers, and also with F=2 degrees of freedom, i.e. as differentials. Moreover, with a two-motor drive they work as a summation planetary gear train and with a one-motor drive, they work as a division planetary gear train. The most popular application of planetary gear trains is as a differential which is bevel and is produced globally in millions of pieces. Some of the cylindrical planetary gear trains can also be used as differentials. Although less often, they are used in heavy wheeled and chain vehicles such as trailer trucks, tractors and tanks. They are also very suitable for lifting machines with a two-motor drive which provides maximum security for the most responsible cranes, such as the metallurgical ones. Initially the paper presents some simple, i.e. single-carrier cylindrical planetary gear trains, both with external and internal meshing, driven by 2 motors. Their kinematic capabilities and velocity, respectively, are considered to realize the necessary gear ratio. Finally, the case of a compound two-carrier planetary gear train is considered, which is composed of 2 simple planetary gear trains. This shows that not only the simple planetary gear trains, i.e. the single-carrier ones, can work as differentials.

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Capturing Assembly Constraints of Experimental Setups in a Virtual Laboratory Environment

Volume 5: Education and Globalization; General Topics ◽

10.1115/imece2012-87828 ◽

2012 ◽

Cited By ~ 2

Author(s):

El-Sayed Aziz ◽

Yizhe Chang ◽

Sven K. Esche ◽

Constantin Chassapis

Keyword(s):

Degrees Of Freedom ◽

Planetary Gear ◽

Gear Train ◽

Virtual Laboratory ◽

Assembly Process ◽

Laboratory Equipment ◽

Planetary Gear Train ◽

Laboratory Environment ◽

Assembly Constraints ◽

Train System

Recently, multi-player game engines have been explored regarding their potential for implementing virtual laboratory environments for engineering and science education. In these developments, the virtual assembly process of the laboratory equipment is a critical step, and a detailed formalized description of how different components of the experimental equipment are to be joined in the assembly process is necessary. This description includes the joint types (lower and upper kinematic pairs) and the associated degrees of freedom, the resulting mobility of the assembly as well as the joint fit requirements. In this paper, a formalized representation of the assembly process that captures the information on the joint kinematics and the components’ degrees of freedom generated when assembling laboratory equipment in a virtual laboratory environment will be discussed. A planetary gear train system will be used as an example to illustrate the proposed method. In particular, the structure of the assembly of a planetary gear train system involves assembly constraints between a group of components (sun, planet and ring gears, shafts, planet carrier assembly, etc.) that generate the desired relationship between the input and output motions. This paper will identify important requirements for modeling different configurations of planetary gear train assemblies within a game-based virtual laboratory environment. These requirements include the positioning and the orienting of the components, the verification of the kinematic joints, the propagation of the mating constraints and the capturing of the joint attributes.

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On the Design of Three Links Robot for Drawing Epicycloid and Hypocycloid Curves

Volume 1: Advanced Energy Systems, Advanced Materials, Aerospace, Automation and Robotics, Noise Control and Acoustics, and Systems Engineering ◽

10.1115/esda2006-95546 ◽

2006 ◽

Author(s):

Meng-Hui Hsu ◽

Zong-You Tsai ◽

Long-Chang Hsieh ◽

Jen-Yu Liu

Keyword(s):

Degrees Of Freedom ◽

Design Method ◽

Planetary Gear ◽

Degree Of Freedom ◽

Gear Train ◽

Major Type ◽

Design Constraints ◽

Two Degrees Of Freedom ◽

Singular Link ◽

Angular Velocities

An epicycloid or hypocycloid mechanism is capable of drawing an exact epicycloid or hypocycloid curve. Similar mechanism designs can be found abundantly in industrial machines or educational equipment. Currently, the major type of epicycloid or hypocycloid configurations is planetary gear trains, which contain a binary link that has one fixed and one moving pivot, and a singular link adjacent to the moving pivot. The main feature of the configurations is that any point on the singular link may describe an epicycloid or hypocycloid curve when the binary link is rotated. Presently, the major types of configurations of epicycloid (hypocycloid) mechanisms have one degree of freedom. However, at present, as far as the authors are concerned, there appears to be no approach in designing epicycloid (hypocycloid) mechanisms with two degrees of freedom. Thus, the main aim of this paper is to develop a new design method in designing new configurations of epicycloid (hypocycloid) mechanisms. This paper analyses the characteristics of the topological structures of existing planetary gear train type epicycloid (hypocycloid) mechanisms with one degree of freedom. The equation of motion and kinematical model of the mechanism was derived and appropriate design constraints and criteria were implemented. Subsequently, using the design constraints and criteria, this work designs a new and simple epicycloid (hypocycloid) mechanism that is a three-links robot and has two degrees of freedom. We can easily control the angular velocities of the binary and singular links to satisfy the criterion to draw an epicycloid (hypocycloid) curve. Additionally, an epicycloid (hypocycloid) path of a point on the three links robot is simulated by computer drawing to prove the feasibility of proposed theory. Finally, a prototype of three links robot for drawing an epicycloid (hypocycloid) path is done well. We know the methods of design and manufacture of the proposed epicycloid or hypocycloid mechanism in linkage is easily done.

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