A vision based error-corrective algorithm for flexible parts assembly

2003 ◽  
Author(s):  
J.Y. Kim ◽  
H.S. Cho
Keyword(s):  
Flexible Parts

Study on Mixed Assembly Modeling of Rigid and Flexible Parts for Aerospace Product Virtual Assembly

2010 ◽  
Vol 431-432 ◽  
pp. 9-12 ◽  
Author(s):  
Dan Zhang ◽  
Dun Wen Zuo ◽  
Guang Ming Jiao ◽  
Jian Xie ◽  
Hua Lin Zhou ◽  
...  
Keyword(s):  
Hierarchical Model ◽  
Graph Model ◽  
Virtual Assembly ◽  
Assembly Process ◽  
Assembly Model ◽  
Assembly Modeling ◽  
Cable Harness ◽  
Modeling Process ◽  
Flexible Parts ◽  
And Storage

According to the characteristics of aerospace product, the model representation and storage of the rigid part and cable harness is proposed. The Dendritic Correlative Model of Mixed Assembly of Rigid and Flexible Parts (DCMMA-RFP) is introduced based on the hierarchical model and graph model. The assembly model which realizes the lightweight storage can clearly represent the hierarchy relation and assembly process of aerospace products. The assembly modeling process in the virtual assembly environment is detailed described. Finally the effectiveness of DCMMA-RFP is verified by an example.

Assembly variation analysis of complicated products based on rigid–flexible hybrid vector loop

2018 ◽  
Vol 233 (10) ◽  
pp. 2099-2114 ◽  
Author(s):  
Zhenyu Liu ◽  
Shien Zhou ◽  
Chan Qiu ◽  
Jianrong Tan
Keyword(s):  
Probability Density ◽  
Loop Model ◽  
Feature Points ◽  
Variation Analysis ◽  
Manufacturing Error ◽  
Density Distributions ◽  
Mechanical Products ◽  
Flexible Parts ◽  
Probability Density Distributions ◽  
Product Assembly

The performance of mechanical products is closely related to their key feature errors. It is essential to predict the final assembly variation by assembly variation analysis to ensure product performance. Rigid–flexible hybrid construction is a common type of mechanical product. Existing methods of variation analysis in which rigid and flexible parts are calculated separately are difficult to meet the requirements of these complicated mechanical products. Another methodology is a result of linear superposition with rigid and flexible errors, which cannot reveal the quantitative relationship between product assembly variation and part manufacturing error. Therefore, a kind of complicated products’ assembly variation analysis method based on rigid–flexible vector loop is proposed in this article. First, shapes of part surfaces and sidelines are estimated according to different tolerance types. Probability density distributions of discrete feature points on the surface are calculated based on the tolerance field size with statistical methods. Second, flexible parts surface is discretized into a set of multi-segment vectors to build vector-loop model. Each vector can be orthogonally decomposed into the components representing position information and error size. Combining the multi-segment vector set of flexible part with traditional rigid part vector, a uniform vector-loop model is constructed to represent rigid and flexible complicated products. Probability density distributions of discrete feature points on part surface are regarded as inputs to calculate assembly variation values of products’ key features. Compared with the existing methods, this method applies to the assembly variation prediction of complicated products that consist of both rigid and flexible parts. Impact of each rigid and flexible part’s manufacturing error on product assembly variation can be determined, and it provides the foundation of parts tolerance optimization design. Finally, an assembly example of phased array antenna verifies effectiveness of the proposed method in this article.

scholarly journals Analysis of Contact Mechanical Characteristics of Flexible Parts in Harmonic Gear Reducer

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Fanjie Li ◽  
Xiaopeng Li ◽  
Yajing Guo ◽  
Dongyang Shang
Keyword(s):  
Mechanical Characteristics ◽  
Angular Displacement ◽  
Excitation Frequency ◽  
Element Model ◽  
Industrial Robots ◽  
Axial Distance ◽  
Axial Vibration ◽  
Cylinder Length ◽  
Flexible Parts ◽  
Contact Mechanical

Harmonic gear reducer is widely used in industrial robots, aerospace, optics, and other high-end fields. The failure of harmonic gear reducer is mainly caused by the damage of flexible bearing and flexspline of thin-walled vulnerable components. To study the contact mechanical characteristics of flexible components such as flexible bearing and flexspline in harmonic gear reducer, the contact mechanical model of flexible bearing, vibration differential equation of flexspline, and finite element model of each component in harmonic gear reducer were established. Based on the established model of harmonic gear reducer, the influence of the length of flexspline cylinder and the thickness of cylinder bottom on the stress of flexspline is discussed, respectively, and the motion characteristics of flexible bearing are studied. At the same time, the spatial distribution of the displacement of the flexspline and the axial vibration response of the flexspline are studied. The correctness of the model established in this paper is verified by experiments. The results show that the increase of cylinder length can improve the stress of flexspline in harmonic gear reducer; the wall thickness of cylinder bottom mainly affects the stress at the bottom of flexspline but has little effect on the stress of gear ring and smooth cylinder. Along the axis direction of the flexspline, the radial displacement, circumferential displacement, and angular displacement increase linearly with the increase of the axial distance between the cylinder and the bottom. When the excitation frequency is high, the vibration mode of flexspline shell is mainly axial vibration. The research results will provide a theoretical reference for the optimal design of harmonic gear reducer and improving the service life of flexible parts.

scholarly journals Dynamic modeling and chatter analysis of a spindle-workpiece-tailstock system for the turning of flexible parts

2019 ◽  
Vol 104 (5-8) ◽  
pp. 3007-3015 ◽  
Author(s):  
Kaibo Lu ◽  
Yongqiang Wang ◽  
Fengshou Gu ◽  
Xinyu Pang ◽  
Andrew Ball
Keyword(s):  
Dynamic Modeling ◽  
Flexible Parts

scholarly journals Analysis of Influence of a Crane Flexible Supports, Link Flexibility, and Joint Friction on Vibration Associated with Programmed Motion Execution

2019 ◽  
Vol 8 (2) ◽  
pp. 337-350 ◽  
Author(s):  
Elżbieta Jarzębowska ◽  
Andrzej Urbaś ◽  
Krzysztof Augustynek
Keyword(s):  
Dynamic Models ◽  
Computational Procedure ◽  
Task Demands ◽  
Constrained Systems ◽  
Constrained Motion ◽  
Joint Friction ◽  
Flexible Supports ◽  
Flexible Parts ◽  
Link Flexibility ◽  
Service Task

Abstract Background The paper presents vibration analysis of dynamic models of systems with flexible mechanical components, friction modeled and subjected to position and kinematic programmed constraints, which can be imposed as control goals, work or service task demands. Methods The constrained dynamics is derived using an automated computational procedure dedicated to constrained systems. The procedure was successfully implemented to rigid system models. A class of systems composed of flexible parts and subjected to programmed motions is considered in the paper. Their motion analysis has to be accompanied by vibration inspection. The novelty of the presented approach is in the possibility of analyzing system motions and vibrations that can be induced by the presence of programmed constraints. Conclusions The constrained motion is examined by the example of a crane model equipped with a flexible link, e.g. a jib, friction modeled in its joints and subjected to programmed constraints. The example delivers a realistic work situation, in which the crane carries loads and moves according to the programmed constraint put on motion.

Research on Influence of Flexible Parts’ Rigidity to Passenger Car Exhaust System’s Modal

2011 ◽  
Vol 117-119 ◽  
pp. 141-145
Author(s):  
Shou Li Yuan ◽  
Wen Chang Zhang ◽  
Zhi En Liu ◽  
Chao Wang ◽  
Ding Yuan Fu
Keyword(s):  
Finite Element ◽  
Natural Frequencies ◽  
Exhaust System ◽  
Fe Model ◽  
Passenger Cars ◽  
Passenger Car ◽  
Finite Element Software ◽  
Modeling Methods ◽  
Car Exhaust ◽  
Flexible Parts

The finite element modeling methods of a passenger car exhaust system’s flexible parts are introduced. A finite element (FE) model of the exhaust system is established with the finite element software and modal analysis of the FE Model is carried out. Through changing both automotive exhaust hangers’ Z direction of stiffness and bellows’ each direction of stiffness, the data of natural frequencies and vibrating modes of the exhaust system were obtained respectively. Comparing and analyzing the results indicates how the stiffness of exhaust hangers and bellows influences the modal of passenger cars’ exhaust system.

Simulation Modelling and Control of Mechatronic Systems with Flexible Parts

Mechatronics ◽  
2011 ◽  
pp. 569-578 ◽  
Author(s):  
T. Brezina ◽  
J. Vetiska ◽  
Z. Hadas ◽  
L. Brezina
Keyword(s):  
Simulation Modelling ◽  
Mechatronic Systems ◽  
Flexible Parts ◽  
And Control

Exploring the Multi-Stage Effects of Material Preparation and Printing on 3D Printing Product Quality

2019 ◽  
Author(s):  
Sahand Hajifar ◽  
Ramanarayanan Purnanandam ◽  
Hongyue Sun ◽  
Chi Zhou
Keyword(s):  
3D Printing ◽  
Material Properties ◽  
Good Property ◽  
Metal Powders ◽  
Promising Technique ◽  
Printing Process ◽  
Multi Stage ◽  
Flexible Parts ◽  
Printing Processes ◽  
Material Preparation

Abstract 3D printing is a promising technique to fabricate flexible parts and reduce the supply chain. Various materials, such as metal powders, plastics, ultraviolet (UV) sensitive resins, can be fabricated from 3D printing and form the final printed part. Currently, most researchers either focus on exploring printable materials with good property or focus on the process quality control given a certain type of material. However, for many 3D printing processes, the printing process and product properties are dependent on both the material properties and process settings. To the best of the authors’ knowledge, the quantitative analysis of the interactions of material properties and printing process settings are rarely studied. In this paper, we treat the material preparation and 3D printing as different manufacturing stages, and we explore the multi-stage effects in 3D printing. In particular, we add carbon fiber to the CLEAR resin to alter the material properties for a stereolithography (SLA) 3D printing process. It is observed that the part properties are jointly affected by material properties and printing process settings. Therefore, the material property and process settings should be jointly considered for optimizing 3D printing processes.

Sign in / Sign up

Export Citation Format

Share Document