Kinematic Acquisition of Geometric Constraints for Task Centered Mechanism Design

2010 ◽  
Author(s):  
Jun Wu ◽  
Q. J. Ge ◽  
Hai-Jun Su ◽  
Feng Gao
Keyword(s):  
Mechanism Design ◽  
Motion Analysis ◽  
Geometric Constraints ◽  
Planar Motion ◽  
Dimensional Synthesis ◽  
Constrained Motion ◽  
Analysis Problem ◽  
Geometric Means ◽  
New Type ◽  
Mechanical Linkage

A motion task can be given in various ways. It may be defined parametrically or discretely in terms of an ordered sequence of displacements or in geometric means. This paper studies a new type of motion analysis problem in planar kinematics that seeks to acquire geometric constraints associated with a planar motion task which is given either parametrically or discretely. The resulting geometric constraints can be used directly for type as well as dimensional synthesis of a physical device such as mechanical linkage that generates the constrained motion task. Methods for kinematic acquisition of geometric constraints bridge the gap between type and dimensional synthesis and provide the foundation for task centered mechanism design.

Kinematic Acquisition of Geometric Constraints for Task-Oriented Design of Planar Mechanisms

2012 ◽  
Vol 5 (1) ◽  
Author(s):  
Jun Wu ◽  
Q. J. Ge ◽  
Hai-Jun Su ◽  
Feng Gao
Keyword(s):  
Mechanism Design ◽  
Geometric Constraints ◽  
Dimensional Synthesis ◽  
Constrained Motion ◽  
Planar Mechanisms ◽  
Analysis Problem ◽  
Geometric Means ◽  
New Type ◽  
Mechanical Linkage ◽  
Task Oriented

A motion task can be given in various ways. It may be defined parametrically or discretely in terms of an ordered sequence of displacements or in geometric means. This paper studies a new type of motion analysis problem in planar kinematics that seeks to acquire geometric constraints associated with a planar motion task which is given either parametrically or discretely. The resulting geometric constraints can be used directly for type as well as dimensional synthesis of a physical device such as mechanical linkage that generates the constrained motion task. Examples are provided toward the end of the paper to illustrate how geometric constraints acquired can be used for task-oriented mechanism design.

scholarly journals A Line Geometric Approach to Kinematic Acquisition of Geometric Constraints of Planar Motion

2017 ◽  
Vol 9 (4) ◽  
Author(s):  
Jun Wu ◽  
Xiangyun Li ◽  
Q. J. Ge ◽  
Feng Gao ◽  
Xueyin Liu
Keyword(s):  
Geometric Approach ◽  
Geometric Constraints ◽  
Planar Motion ◽  
Constrained Motion ◽  
Discrete Form ◽  
Mechanical Linkage

This paper examines the problem of geometric constraints acquisition of planar motion through a line-geometric approach. In previous work, we have investigated the problem of identifying point-geometric constraints associated with a motion task which is given in a parametric or discrete form. In this paper, we seek to extend the point-centric approach to the line-centric approach. The extracted geometric constraints can be used directly for determining the type and dimensions of a physical device such as mechanical linkage that generates this constrained motion task.

Paper 6: Electronic Instrumentation Techniques in the Development of Pistons and Rings

1965 ◽  
Vol 180 (7) ◽  
pp. 54-69 ◽  
Author(s):  
M. H. Westbrook ◽  
R. Munro
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Extreme Conditions ◽  
Dynamic Measurements ◽  
Inductive Transducer ◽  
New Type ◽  
Electronic Instrumentation ◽  
Mechanical Linkage ◽  
Contact Displacement ◽  
Engine Development

Both general and particular aspects of the application of electronic instrumentation in internal combustion engine development are discussed, and the work which has been carried out in the authors' establishment on instrumentation for dynamic measurements on the piston assembly is described, in particular, measurements of engine noise and vibration, and of displacement and temperature during operation, using telemetry systems, and making use of both radio and mechanical linkage techniques. The development of a new type of sub-miniature inductive transducer for non-contact displacement measurement under the extreme conditions inside a working piston is described, and the reasons making its development necessary discussed. Results obtained from a working engine showing piston movements as measured by several inductive transducers and transmitted over the linkage system are shown and compared to block vibration recordings made simultaneously; an initial interpretation of the very recent results is made. Finally, electronic methods developed for the static measurement of piston and ring properties are described and the results obtained discussed.

Constraint-Based Virtual Environment for Supporting Assembly and Maintainability Tasks

1999 ◽  
Author(s):  
Terrence Fernando ◽  
Prasad Wimalaratne ◽  
Kevin Tan
Keyword(s):  
Virtual Environment ◽  
Current System ◽  
Research Programme ◽  
Geometric Constraints ◽  
Simulation Environment ◽  
Constrained Motion ◽  
Constraint Management ◽  
Interactive Product ◽  
Assembly Operations ◽  
The University

Abstract This paper presents the design and implementation of a constraint-based virtual environment for supporting interactive assembly and maintenance tasks. The system architecture of the constraint-based virtual environment is based on the integration of components such as OpenGL Optimizer, Parasolid geometric kernel, a Constraint Engine and an Assembly Relationship Graph (ARG). The approach presented in this paper is based on pure geometric constraints. Techniques such as automatic constraint recognition, constraint satisfaction, constraint management and constrained motion are employed to support interactive assembly operations and realistic behaviour of assembly parts. The current system has been evaluated using two industrial case studies. This work is being carried out as a part of a research programme referred to as IPSEAM (Interactive Product Simulation Environment for Assessing Assembly and Maintainability), at the University of Salford.

Optimum dimensional synthesis of planar mechanisms with geometric constraints

Meccanica ◽  
2020 ◽  
Vol 55 (11) ◽  
pp. 2135-2158
Author(s):  
V. García-Marina ◽  
I. Fernández de Bustos ◽  
G. Urkullu ◽  
R. Ansola
Keyword(s):  
Geometric Constraints ◽  
Dimensional Synthesis ◽  
Planar Mechanisms

Dimensional Synthesis and Constrained Motion Interpolation for Planar and Spherical 6R Closed Chains

2008 ◽  
Author(s):  
Anurag Purwar ◽  
Zhe Jin ◽  
Qiaode Jeffrey Ge
Keyword(s):  
Rational Curve ◽  
Dimensional Synthesis ◽  
Constrained Motion ◽  
Initial Attempt ◽  
Kinematic Constraints ◽  
Constraint Manifold ◽  
Cartesian Space ◽  
Closed Chain ◽  
Kinematic Mapping ◽  
The Given

In the recent past, we have studied the problem of synthesizing rational interpolating motions under the kinematic constraints of any given planar and spherical 6R closed chain. This work presents some preliminary results on our initial attempt to solve the inverse problem, that is to determine the link lengths of planar and spherical 6R closed chains that follow a given smooth piecewise rational motion under the kinematic constraints. The kinematic constraints under consideration are workspace related constraints that limit the position of the links of planar and spherical closed chains in the Cartesian space. By using kinematic mapping and a quaternions based approach to represent displacements of the coupler of the closed chains, the given smooth piecewise rational motion is mapped to a smooth piecewise rational curve in the space of quaternions. In this space, the aforementioned workspace constraints on the coupler of the closed chains define a constraint manifold representing all the positions available to the coupler. Thus the problem of dimensional synthesis may be solved by modifying the size, shape and location of the constraint manifolds such that the mapped rational curve is contained entirely inside the constraint manifolds. In this paper, two simple examples with preselected moving pivots on the coupler as well as fixed pivots are presented to illustrate the feasibility of this approach.

4MDS: A Geometric Constraint Based Motion Design Software for Synthesis and Simulation of Planar Four-Bar Linkages

2014 ◽  
Author(s):  
Anurag Purwar ◽  
Abhijit Toravi ◽  
Q. J. Ge
Keyword(s):  
Real Time ◽  
Geometric Constraints ◽  
Geometric Constraint ◽  
Design System ◽  
Dimensional Synthesis ◽  
Complete Control ◽  
Dimensional Changes ◽  
Design Software ◽  
Four Bar Linkage ◽  
Motion Design

This paper presents our recent work on designing and developing a geometric constraint based motion design software system for planar four-bar linkages. Given a motion task, the software computes possible four-bar linkage topologies as well as its dimensions. This capability to analyze the given task and find the best type of the linkage and the dimensions simultaneously sets it apart from any other linkage design software. The Four-Bar Motion Design System (4MDS) makes the synthesis and simulation capabilities available to mechanism designers in an intuitive graphical user interface (GUI) environment. Instead of taking a black box approach to mechanism design, wherein the user simply enters the motion requirements and the software outputs parameters of mechanisms, this software facilitates a dialog with the designer by providing various paths to simulation and synthesis in a design session. The designer has complete control over the specification of motion task, interactive tweaking of the motion, choice of linkage topology computed, dimensional changes, and their apparent effect on motion, all done in real time. This interactivity enhances designers kinematic experience. The underlying theoretical foundation of this paper is based on our earlier work on a task-driven approach to unified type and dimensional synthesis of planar four-bar linkage mechanisms. Instead of treating a planar four-bar mechanism as a set of connected rigid links and joints, we treat them as line or circle constraint generators. With that view, the synthesis problem is reduced to extracting geometric constraints hidden in a given motion task and the simulation is reduced to assembling constraints realizable by mechanical dyads. The algorithm employed is simple and efficient and permits real-time computation, and thus precludes using a limiting database-oriented approach. This tool should make innovation of mechanical motion generating devices accessible to novice and experienced designers alike.

Mechanism Design of the Automatic Adjustment of the Number of Inserting Fuses of the Inserting Fuse Machine for Firecracker

2013 ◽  
Vol 842 ◽  
pp. 624-628
Author(s):  
Guo Ping Liu ◽  
Wei Qiang Wang ◽  
Zhi Yong Cai ◽  
Rong Hua Hu
Keyword(s):  
Mechanism Design ◽  
Production Efficiency ◽  
Circular Cylinders ◽  
Automatic Adjustment ◽  
Via Holes ◽  
New Type

Currently, its problems are about feeding more and inserting less fuses at a time, needing triple cooperation of rotary pairs, locations, and low production efficiency. A new type of feed of fuses mechanism was designed, its automatic adjustment of the number of inserting fuses can come out by means of the transmission fit of the trapezoidal axis with the via holes. The axis is a quadrangular prism in the middle and circular cylinders on both sides and the holes are in the middle of the pulling roll wheel pieces. It greatly improves the production efficiency.

Topological Synthesis for Linkage Mechanism Design Using the Minimum Potential Energy Principle

2005 ◽  
Author(s):  
Hae Chang Gea ◽  
Jaehyun Kwon
Keyword(s):  
Potential Energy ◽  
Mechanism Design ◽  
Compliant Mechanism ◽  
Analysis Method ◽  
Dimensional Synthesis ◽  
Linkage Mechanism ◽  
Minimum Potential Energy ◽  
Minimum Potential ◽  
Number Synthesis ◽  
Topological Synthesis

A mechanism is a device transmits motion in a predetermined manner in order to accomplish specific objectives. Mechanism design can be divided into three steps: type synthesis, number synthesis and dimensional synthesis, where the number synthesis is also called topological synthesis. In this paper, a new approach for topological synthesis and dimensional synthesis of linkage mechanism design with pin joints is presented. This approach is based on the discrete element approach which always provides clear definitions of number of linkages and joints. In order to extend its applications beyond the compliant mechanism, a novel analysis method based on the principle of minimum potential energy for linkage topology optimization is employed. Unlike the traditional FEM based approaches, this novel analysis method can be applied to multiple joint linkage designs directly. Genetic Algorithm is chosen as the optimizer. Finally, a few design examples from the proposed method are presented.

Sign in / Sign up

Export Citation Format

Share Document