Design and Analysis of a Novel Wall-Climbing Robot Mechanism

A novel wall-climbing robot mechanism designed for anti-hijacking task is presented. This mechanism consists of a negative pressure adhesion module, a vacuum suction module and a planetary-gear train. The design of biped-wheel hybrid locomotion mechanism, with the advantages of wheeled robots and legged robots, allows the robot to move fast and cross over obstacles easily. This design qualifies the robot for the motion of moving straight, turning in plane and crossing between inclined surfaces. Then the kinematics equations are derived and the locomotion modes are analyzed. Many experiments have been implemented and the results prove that the robot has such characteristics as rapid speed, excellent transition ability between inclined surfaces and curved surface adaptability. Therefore, this novel wall-climbing mechanism could be used for the application of inspection, surveillance and reconnaissance.

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Dynamic Modeling and Simulation of a Novel Wall-Climbing Robot

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.336-338.1180 ◽

2013 ◽

Vol 336-338 ◽

pp. 1180-1185 ◽

Cited By ~ 1

Author(s):

Wei Guang Dong ◽

Hong Guang Wang ◽

Yong Jiang

Keyword(s):

Modeling And Simulation ◽

Dynamic Model ◽

Dynamic Modeling ◽

Adhesion Force ◽

Great Influence ◽

The Novel ◽

Climbing Robot ◽

Motion Direction ◽

Inclined Surfaces ◽

Hybrid Locomotion

The dynamic modeling and simulation of a novel wall-climbing robot is presented. For the novel biped-wheel hybrid locomotion mechanism of the robot, its locomotion modes and typical state of motion are analyzed. Based on the description of the robots pose, the dynamic model for two typical states of motion, point turning in a flat surface and transition between two intersecting surfaces, is established. The equation for calculating adhesion force when the robot moves on arbitrary inclined surfaces is derived from the dynamic model. Simulations for the adhesion force are implemented with three typical examples. The results show that the tilt angle of the attachment surface and the motion direction of the robot have great influence on the adhesion force.

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Design and Kinematic Aspects of a Hybrid Locomotion Robot

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1036.764 ◽

2014 ◽

Vol 1036 ◽

pp. 764-769

Author(s):

Alina Conduraru Slatineanu ◽

Ioan Doroftei ◽

Ionel Conduraru

Keyword(s):

High Speed ◽

Mechanical Design ◽

Real Life ◽

Legged Robots ◽

Control Algorithms ◽

Wheeled Robots ◽

Flat Surfaces ◽

Difficult Terrain ◽

Hybrid Locomotion ◽

And Control

Comparing to wheeled robots, legged ones are more flexible and mobile on difficult terrain, where wheeled robots cannot go. Wheels excel on flat surfaces or specially prepared surfaces, where wheeled robots are faster than legged machines. Also, wheeled platforms have simpler mechanical architecture and control algorithms. But they do not perform well when terrain is uneven, which is the case in real life, legged robots becoming more interesting to research and explore. Hybrid locomotion systems were developed to exploit the terrain adaptability of legs in rough terrain and simpler control as well as high speed associated with wheels. In this paper some information about the mechanical design and kinematics of a small hybrid locomotion robot are presented.

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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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A New Technique Based on Loops to Investigate Displacement Isomorphism in Planetary Gear Trains

Journal of Mechanical Design ◽

10.1115/1.1503373 ◽

2002 ◽

Vol 124 (4) ◽

pp. 662-675 ◽

Cited By ~ 17

Author(s):

V. V. N. R. Prasad Raju Pathapati ◽

A. C. Rao

Keyword(s):

Graph Isomorphism ◽

Planetary Gear ◽

Degree Of Freedom ◽

Gear Train ◽

Graph Representation ◽

Kinematic Structure ◽

Graph Representations ◽

Planetary Gear Trains ◽

Gear Trains ◽

A New Technique

The most important step in the structural synthesis of planetary gear trains (PGTs) requires the identification of isomorphism (rotational as well as displacement) between the graphs which represent the kinematic structure of planetary gear train. Previously used methods for identifying graph isomorphism yielded incorrect results. Literature review in this area shows there is inconsistency in results from six link, one degree-of-freedom onwards. The purpose of this paper is to present an efficient methodology through the use of Loop concept and Hamming number concept to detect displacement and rotational isomorphism in PGTs in an unambiguous way. New invariants for rotational graphs and displacement graphs called geared chain hamming strings and geared chain loop hamming strings are developed respectively to identify rotational and displacement isomorphism. This paper also presents a procedure to redraw conventional graph representation that not only clarifies the kinematic structure of a PGT but also averts the problem of pseudo isomorphism. Finally a thorough analysis of existing methods is carried out using the proposed technique and the results in the category of six links one degree-of-freedom are established and an Atlas comprises of graph representations in conventional form as well as in new form is presented.

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Dynamic Load Sharing Behavior of Planetary Gear Train with Backlashes

2009 International Conference on Engineering Computation ◽

10.1109/icec.2009.13 ◽

2009 ◽

Cited By ~ 2

Author(s):

Yan-feng Chen ◽

Xing-yue Wu

Keyword(s):

Dynamic Load ◽

Planetary Gear ◽

Load Sharing ◽

Gear Train ◽

Planetary Gear Train ◽

Dynamic Load Sharing ◽

Sharing Behavior

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Dynamics of the Gear Train Set in Wind Turbine

Materials Science Forum ◽

10.4028/www.scientific.net/msf.697-698.701 ◽

2011 ◽

Vol 697-698 ◽

pp. 701-705

Author(s):

D.D. Ji ◽

Y.M. Song ◽

J. Zhang

Keyword(s):

Wind Turbine ◽

Dynamic Model ◽

Harmonic Balance Method ◽

Planetary Gear ◽

Gear Train ◽

Dynamic Responses ◽

Multi Stage ◽

Lumped Parameter ◽

Cartesian Coordinate ◽

The Impact

A lumped-parameter dynamic model for gear train set in wind turbine is proposed to investigate the dynamics of the speed-increasing gear box. The proposed model is developed in a universal Cartesian coordinate, which includes transversal and torsional deflections of each component, time-varying mesh stiffness, gear profile errors and external excitations. By solving the dynamic model, a modal analysis is performed. The results indicate that the modal properties of the multi-stage gear train in wind turbine are similar to those of a single-stage planetary gear set. A harmonic balance method (HBM) is used to obtain the dynamic responses of the gearing system. The responses give insight into the impact of excitations on the vibrations.

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Analysis of Models for Torsional Vibration of Shaft System With Planetary Gearing

Volume 1B: 16th Biennial Conference on Mechanical Vibration and Noise ◽

10.1115/detc97/vib-4036 ◽

1997 ◽

Author(s):

Jinghui Sun ◽

Lee Liu ◽

William N. Patten

Keyword(s):

Torsional Vibration ◽

Planetary Gear ◽

Gear Train ◽

Mathematical Treatment ◽

Dynamic Parameters ◽

Mass Model ◽

Planar Model ◽

Shaft System ◽

Effective Dynamic ◽

Single Mass

Abstract The kinematics of planetary gearing are complex; thus, making it difficult to build an effective dynamic model. In this paper, a single-mass model of a planetary gear and shaft system is developed to study the torsional vibration of the mechanism. Two new models of the system are proposed: (a) a fictitious co-planar model and (b) an equivalent shaft model. The results from the calculations and analyses using these models indicate that: 1) the single-mass model and the general rotary model are both limited, either mathematically or geometrically; 2) the fictitious co-planar model includes all of the geometric and dynamic parameters of the general rotary model, and it can be connected with the shaft system easily; and 3) using a mathematical treatment, the equivalent shaft model is demonstrated to be the most useful and most effective model for the calculation of torsional vibration of a shaft and planetary gear train.

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Vibrational Monitoring of Nested Planetary Geartrain with Unground Pinion

INTER-NOISE and NOISE-CON Congress and Conference Proceedings ◽

10.3397/in-2021-1852 ◽

2021 ◽

Vol 263 (5) ◽

pp. 1471-1487

Author(s):

Jianxiong Feng ◽

Yangfan Liu ◽

Kai Ming Li

Keyword(s):

Frequency Spectrum ◽

Spectrum Analysis ◽

Time History ◽

Critical Factor ◽

Planetary Gear ◽

Gear Train ◽

Frequency Spectrum Analysis ◽

Vibration Strength ◽

Automobile Transmissions ◽

Modulation Sideband

The nested planetary gear train, which has two integrated single-stage planetary gearsets, is one of the newly developed compound gear train that has been successfully applied to the automobile transmissions. In the current study, a certain type of gear fault in the nested gear train, ungrounded pinion, is investigated using a non-destructive approach monitoring its vibration levels. A novel experimental test stand with open and vertical setup has been designed to collect the vibrational data by mounting the accelerometer directly to the gear clutches. Each of the two layers of the compound gear was tested separately. The measured vibrational data were processed with several signal processing techniques, which includes (a) frequency spectrum analysis, (b) time synchronous averaging (TSA) and (c) modulation sideband analysis. The experimental results show that the existence of the ungrounded pinion can be identified with the frequency spectrum analysis of the vibrational data. In addition, the modulation sidebands are also modeled using a modified version of the traditional technique of physical signal modeling. It is shown that the relative phase of the planet and the meshing vibration strength changed by the unground gear is the critical factor for determining the modulation sideband behavior. In addition, the location of the ungrounded pinion can also be determined by the time history processed by TSA.

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