A unified structure theory of multibody open-, closed-, and mixed-loop mechanical systems with simple and multiple joint kinematic chains

2016 ◽  
Vol 100 ◽  
pp. 1-16 ◽  
Author(s):  
Vladimir Pozhbelko
Keyword(s):  
Mechanical Systems ◽  
Structure Theory ◽  
Joint Kinematic ◽  
Kinematic Chains

Automatic Generation of Equations of Motion of Mechanical Systems

2014 ◽  
Vol 611 ◽  
pp. 40-45
Author(s):  
Darina Hroncová ◽  
Jozef Filas
Keyword(s):  
Computer Simulation ◽  
Degrees Of Freedom ◽  
Equations Of Motion ◽  
Mechanical Systems ◽  
Automatic Generation ◽  
Lagrange Equations ◽  
Kinematic Chains ◽  
Transformation Matrices

The paper describes an algorithm for automatic compilation of equations of motion. Lagrange equations of the second kind and the transformation matrices of basic movements are used by this algorithm. This approach is useful for computer simulation of open kinematic chains with any number of degrees of freedom as well as any combination of bonds.

Application of the Vector-Network Method to Constrained Mechanical Systems

1986 ◽  
Vol 108 (4) ◽  
pp. 471-480 ◽  
Author(s):  
Tai-Wai Li ◽  
Gordon C. Andrews
Keyword(s):  
Equations Of Motion ◽  
Mechanical Systems ◽  
Computer Applications ◽  
Kinematic Chains ◽  
Constrained Mechanical Systems ◽  
3 Dimensional ◽  
Methodical Approach ◽  
Dynamic Formulation ◽  
Reaction Forces ◽  
New Formulation

The vector-network technique is a methodical approach to formulating equations of motion for unconstrained dynamic systems, utilizing concepts from graph theory and vectorial mechanics; it is ideally suited to computer applications. In this paper, the vector-network theory is significantly improved and extended to include constrained mechanical systems with both open and closed kinematic chains. A new formulation procedure is developed in which new kinematic constraint elements are incorporated. The formulation is based on a modified tree/cotree classification, which deviates significantly from previous work, and reduces the number of equations of motions to be solved. The dynamic equations of motion are derived, with generalized accelerations and a subset of the reaction forces as solution variables, and a general kinematic analysis procedure is also developed, similar to that of the dynamic formulation. Although this paper restricts most discussions to two-dimensional (planar) systems, the new method is equally applicable to 3-dimensional systems.

Analysis of Proportional—Derivative and Nonlinear Control of Mechanical Systems with Dynamic Backlash

2003 ◽  
Vol 9 (1-2) ◽  
pp. 119-155 ◽  
Author(s):  
M. T. Mata-Jiménez ◽  
B. Brogliato
Keyword(s):  
Rigid Body ◽  
Mechanical System ◽  
Hybrid Control ◽  
Mechanical Systems ◽  
Unilateral Constraints ◽  
Discrete Events ◽  
Complete Proof ◽  
Kinematic Chains ◽  
Constrained Mechanical Systems ◽  
Treat All

In this paper, we focus on the analysis and control of a simple rigid-body mechanical system with clearance. Contrary to most of the existing works in the literature concerning control, we explicitly treat all the nonlinear non-smooth characteristics of this system considered as a rigid-body mechanical system with unilateral constraints and impacts (dynamic backlash). The model is therefore a hybrid dynamical system, mixing discrete events as well as continuous states. The regulation and tracking capabilities of the proportional—derivative (PD) scheme are investigated. In particular, a complete proof of the existence of a limit cycle for non-collocated PD control is provided, including viability constraints. It is concluded that tracking requires the development of specific control schemes. Consequently, we propose a hybrid control that may be used to track some desired trajectories in conjunction with a PD input. Throughout the paper, the particular features of unilaterally constrained mechanical systems are taken into account, such as the fundamental viability property of closed-loop solutions and controls. This work is a new approach to be considered for application in several areas including the control of kinematic chains with joint clearance and vibro-impact systems, as well as liquid slosh control. Numerical results are presented to illustrate the possible performance of the proposed control scheme and its robustness properties.

The Establishment of Novel Structure Representation Models for Several Kinds of Mechanisms

2009 ◽  
Author(s):  
Huafeng Ding ◽  
Jing Zhao ◽  
Zhen Huang
Keyword(s):  
Topological Graph ◽  
Planar Mechanisms ◽  
Topological Graphs ◽  
Structure Representation ◽  
Joint Kinematic ◽  
Kinematic Chains ◽  
Mathematical Representations ◽  
Novel Structure ◽  
Structure Synthesis ◽  
Topological Models

This paper attempts to establish the unified topological models and corresponding mathematical representations for planar simple joint, multiple joint and geared (cam) kinematic chains. First, the conventional topological representation models of kinematic chains are introduced. Then new topological models of multiple joint and geared (cam) kinematic chains, which are derived from the topological graph of simple joint kinematic chains, are presented. The characteristics of the new topological graphs and their associations with the topological graph of simple joint kinematic chains are also addressed. The most important merit of the new topological graphs is that it makes it much easier to do unified structure synthesis and further establish conceptual design platform for various planar mechanisms of these kinds.

An Automatic Method for Sketching of Planar Simple and Multiple Joint Kinematic Chains

2015 ◽  
Author(s):  
Huafeng Ding ◽  
Peng Huang ◽  
Zhen Huang ◽  
Andrés Kecskeméthy
Keyword(s):  
Mechanical Design ◽  
Kinematic Chain ◽  
Design Stage ◽  
Automatic Method ◽  
Topological Graph ◽  
Joint Kinematic ◽  
Kinematic Chains ◽  
Visual Understanding ◽  
Fully Automatic ◽  
Edge Crossings

The sketching of mechanisms (kinematic chains) shows designers a visual understanding of the interrelationship among links and joints in mechanical design, but sketching of mechanisms in manually in conceptual design stage is time-consuming and inefficient. In this paper, a fully-automatic method for sketching of planar simple and multiple joint kinematic chains is proposed. First, the complete sets of the topological structures (topological graphs and contracted graphs) of both simple and multiple joint kinematic chains are introduced. Then an algorithm for the layouts of the contracted graphs with minimal edge crossings is proposed. Third, the expression set of binary sub-paths derived from a topological graph is obtained for the sketching of the simple joint kinematic chain, and based on the sketching of the simple joint kinematic chains the sketching of corresponding multiple joint kinematic chains is obtained. Finally, both simple and multiple joint kinematic chains with numbers of links and numbers of basic loops are provided in batch as examples to show the effectiveness of the method.

Generation of Planar Kinematic Chains With One Multiple Joint

2013 ◽  
Author(s):  
Huafeng Ding ◽  
Weijuan Yang ◽  
Peng Huang ◽  
Li Ma ◽  
Andrés Kecskeméthy
Keyword(s):  
Conceptual Design ◽  
Degrees Of Freedom ◽  
Characteristic Number ◽  
Automatic Method ◽  
Topological Graph ◽  
Topological Graphs ◽  
Systematic Method ◽  
Joint Kinematic ◽  
Kinematic Chains ◽  
First Time

It is very important to synthesize as many feasible kinematic structures of mechanisms as possible in the conceptual design of mechanisms. Besides simple joint mechanisms, multiple joint mechanisms are also widely used in various mechanical systems. This paper proposes an automatic method for the synthesis of planar multiple joint kinematic chains which are seldom addressed in literature. The bicolor topological graph and the bicolor contracted graph are adopted to represent the topological structures of multiple joint kinematic chains. The characteristic number string of bicolor topological graphs is proposed and used to detect efficiently isomorphism in the synthesis progress. A systematic method for the synthesis of kinematic chains with one multiple joint is proposed, and the whole families of multiple joint kinematic chains with up to 16 links and all possible degrees of freedom are obtained for the first time.

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