Synthesis of Kinematic Chains via Method of Cut-Set Matrix With Modulo-2 Operation

1973 ◽  
Vol 95 (3) ◽  
pp. 681-684 ◽  
Author(s):  
M. Huang ◽  
A. H. Soni
Keyword(s):  
Computer Aided Design ◽  
Tree Graph ◽  
Kinematic Chains ◽  
Tree Graphs ◽  
Computer Aided ◽  
Cut Set ◽  
Aided Design ◽  
High Degree

Method of cut-set matrix with modulo-2 operation is used to enumerate all possible tree graphs from a given tree graph. The typical kinematic chains corresponding to the tree graphs are the chains with cams and gears. The equations used to find the number of heavy edges (corresponding to cam or gear joints) and fine edges (corresponding to turning joints) required in the tree graphs are presented. A table of tree graphs and their corresponding cam kinematic chains is prepared. The method is potentially promising for computer-aided design application because of its simplicity, compact notation, and high degree of organization.

scholarly journals Inter and intra-observer errors for postoperative total hip radiographic assessment using computer aided design

2021 ◽  
Vol 87 (1) ◽  
pp. 65-71
Author(s):  
Adnan Faraj ◽  
Mark Andrews ◽  
Weiguang Li
Keyword(s):  
Computer Aided Design ◽  
X Rays ◽  
Radiographic Assessment ◽  
Rater Reliability ◽  
Total Hip ◽  
Computer Aided ◽  
Medical Note ◽  
Aided Design ◽  
High Degree

Plain radiographic assessment of primary total hip arthroplasty following surgery remains to be the commonest radiological assessment. The current paper, studies the accuracy and concordance between observers reviewing these radiographs. A prospective radiographic and medical note review of ten patients who underwent total hip replacement for primary osteoarthritis, with a mean age of 69 years. Early and 6 weeks postoperative x-rays were assessed for hip profile and version profile using computer aided design (CAD) by two observers on two different occasions. The observers were Orthopaedic surgeons who perform arthroplasty of the hip. The results were analyzed statistically. Dimensions, including Femoral offset, medial offset and ilioischial offset showed a high degree of inter- film and intra-film correlation, with inter-class correlation (ICC) over 0.8. Except of the intra-film correlation of ilioischial offset measured on the post- operative films (p=0.067) by the first rater, all the intra and inter film correlation were significantly over the benchmark of 0.6. In terms of stem alignment, cup inclination and cup version, the intra-film correlation by rater n°2 ranges from 0.574 to 0.975 and were significantly over the benchmark of 0.6, except in the case of cup inclination measured on the 6 th? week follow-up ; meanwhile the intra-film correlation by rater n°1 ranges from 0.581 to 0.819 and none were significantly over the benchmark of 0.6. The inter-rater reliability and inter-film correlation showed a dichotomy of results among different dimensions of the measurement. Dimensions of femo- ral offset, medial offset and ilioischial offset showed a substantial degree of reliability in terms of inter-rater reliability, inter-film correlation, and intra-rater/film reliability.

Linkage Characteristic Polynomials: Assembly Theorems, Uniqueness

1982 ◽  
Vol 104 (1) ◽  
pp. 11-20 ◽  
Author(s):  
H. S. Yan ◽  
A. S. Hall
Keyword(s):  
Characteristic Polynomial ◽  
Computer Aided Design ◽  
Characteristic Polynomials ◽  
Topological Information ◽  
Automated Recognition ◽  
Practical Applications ◽  
Kinematic Chains ◽  
Computer Aided ◽  
Aided Design ◽  
Insight Into

Several assembly theorems, for obtaining the linkage characteristic polynomial for a complex chain through a series of steps involving the known polynomials for subunits of the chain, are derived and presented. These theorems give insight into how the topological information concerning the linkage is stored in the polynomial and might contribute to the automated recognition of linkage structure in generalized computer-aided design programs. Based on graph theory, the characteristic polynomial cannot characterize the graph up to isomorphism. However, for practical applications in the field of linkage mechanisms, it is extremely likely that the characteristic polynomials are unique for closed connected kinematic chains without any overconstrained subchains.

Synthesis of Deployable/Foldable Single Loop Mechanisms With Revolute Joints

2011 ◽  
Vol 3 (3) ◽  
Author(s):  
Zongquan Deng ◽  
Hailin Huang ◽  
Bing Li ◽  
Rongqiang Liu
Keyword(s):  
Computer Aided Design ◽  
Geometric Approach ◽  
Mobility Analysis ◽  
Design Models ◽  
Single Loop ◽  
Kinematic Chains ◽  
Design And Synthesis ◽  
Revolute Joints ◽  
Computer Aided ◽  
Aided Design

This paper presents a geometric approach for design and synthesis of deployable/foldable single loop mechanisms with pure revolute joints. The basic kinematic chains with symmetric mobility are first synthesized, and an intuitive geometric method is proposed for the mobility analysis of these kinematic chains. The deployable/foldable single loop mechanisms can be regarded as a combination of the basic kinematic chains with nontrivial mobility intersection, under this approach, the 5R to 8R single loop mechanisms with symmetric mobility are synthesized systematically. The method for determining the positions of the joint axes on polyhedral links is also proposed, so that the mechanism can be fully deployed or fully folded without suffering from physical interference. Under this framework, a class of novel deployable/foldable single loop mechanisms is developed. The computer-aided design models for typical examples are built to illustrate their feasibility.

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