Ergonomic Evaluation Of Virtual Assembly Tasks

Over the years, various approaches have been investigated to support natural human interaction with CAD models in an immersive virtual environment. The motivation for this avenue of research stems from the desire to provide a method where users can manipulate and assemble digital product models as if they were manipulating actual models. The ultimate goal is to produce an immersive environment where design and manufacturing decisions which involve human interaction can be made using only digital CAD models, thus avoiding the need to create costly preproduction physical prototypes. This paper presents a framework to approach the development of virtual assembly applications. The framework is based on a Two Phase model where the assembly task is divided into a free movement phase and a fine positioning phase. Each phase can be implemented using independent techniques; however, the algorithms needed to interface between the two techniques are critical to the success of the method. The paper presents a summary of three virtual assembly techniques and places them within the framework of the Two Phase model. Finally, the conclusions call for the continued development of a testbed to compare virtual assembly methods.

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Poster: A wearable augmented reality system with haptic feedback and its performance in virtual assembly tasks

2013 IEEE Symposium on 3D User Interfaces (3DUI) ◽

10.1109/3dui.2013.6550228 ◽

2013 ◽

Cited By ~ 10

Author(s):

Kazuya Murakami ◽

Ryo Kiyama ◽

Takuji Narumi ◽

Tomohiro Tanikawa ◽

Michitaka Hirose

Keyword(s):

Augmented Reality ◽

Haptic Feedback ◽

Virtual Assembly ◽

Augmented Reality System ◽

Assembly Tasks ◽

Wearable Augmented Reality

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Asymmetric Interface and Interactions for Bimanual Virtual Assembly With Haptics

Volume 2: 32nd Computers and Information in Engineering Conference, Parts A and B ◽

10.1115/detc2012-71543 ◽

2012 ◽

Cited By ~ 1

Author(s):

Vikram S. Vyawahare ◽

Richard T. Stone

Keyword(s):

Multimodal Interaction ◽

Virtual Assembly ◽

Haptic Device ◽

The Other ◽

Single Object ◽

Interaction Method ◽

Tracking Device ◽

The Cost ◽

Object Interactions ◽

Assembly Tasks

This paper discusses development of a new bimanual interface configuration for virtual assembly consisting of a haptic device at one hand and a 6DOF tracking device at the other hand. The two devices form a multimodal interaction configuration facilitating unique interactions for virtual assembly. Tasks for virtual assembly can consist of both “one hand one object” and “bimanual single object” interactions. For one hand one object interactions this device configuration offers advantages in terms of increased manipulation workspace and provides a tradeoff between the cost effectiveness and mode of feedback. For bimanual single object manipulation an interaction method developed using this device configuration improves the realism and facilitates variation in precision of task of bimanual single object orientation. Furthermore another interaction method to expand the haptic device workspace using this configuration is introduced. The applicability of both these methods to the field of virtual assembly is discussed.

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Virtual Assembly With Construction Kits

Volume 4: 3rd Design for Manufacturing Conference ◽

10.1115/detc97/dfm-4363 ◽

1998 ◽

Author(s):

Bernhard Jung ◽

Martin Hoffhenke ◽

Ipke Wachsmuth

Keyword(s):

Virtual Assembly ◽

Structured Model ◽

Input Devices ◽

Virtual Scene ◽

Functional Roles ◽

Mechanical Parts ◽

Knowledge Based ◽

Construction Kits ◽

Manufacturing Applications ◽

Assembly Tasks

Abstract The CODY1Virtual Constructor is a knowledge-based system that enables the interactive assembly of 3D visualized mechanical parts to complex and novel aggregates in a virtual environment. Two interaction modalities are provided: The user may (1) either directly manipulate the virtual scene by grasping, moving, and assembling parts using the mouse or similar input devices; or, (2) the user can instruct the system using simple commands in natural language. The basis for these interaction facilities is provided by a knowledge based approach, COAR (“Concepts for Objects, Assemblies, and Roles”%), that is especially tailored towards the representation of ongoing assembly tasks. In COAR, a structured model of a target aggregate can be specified. The system will then — while an aggregate is assembled in the virtual scene — recognize constructed subassemblies of the target aggregate. Furthermore, if multifunctional parts are used, as is likely when considering standardized construction kits, the system also recognizes the specific functional roles assumed by single parts in different subassemblies. We foresee potential manufacturing applications of virtual assembly (a) in the rapid design of novel assemblies and (b) in planning and simulation of assembly processes.

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3D Object Representation for Physics Simulation Engines and its Effect on Virtual Assembly Tasks

Volume 2: 32nd Computers and Information in Engineering Conference, Parts A and B ◽

10.1115/detc2012-71120 ◽

2012 ◽

Cited By ~ 3

Author(s):

Germanico Gonzalez ◽

Hugo I. Medellin ◽

Theodore Lim ◽

James M. Ritchie ◽

Raymond C. W. Sung

Keyword(s):

Collision Detection ◽

Object Representation ◽

Virtual Assembly ◽

Detection Algorithm ◽

Convex Decomposition ◽

Virtual Objects ◽

Detection Algorithms ◽

Physics Simulation ◽

Assembly Tasks ◽

Simulation Engines

Physical based modelling (PBM) uses physics simulation engines (PSE) to provide the dynamic behaviour and collision detection of virtual objects in virtual environments emulating the real world. There exists a variety of PSEs, each one with pros and cons according to the application in which they are employed. Each physics engine uses its proprietary collision detection algorithm. Collision detection is a key aspect of assembly tasks and its performance is dependent on the way virtual objects are represented. In general, objects can be divided into two groups: convex and concave, the latter being the most common and challenging for collision detection algorithms. This study reports on three different methods to represent concave objects. GIMPACT, Hierarchical Approximate Convex Decomposition (HACD) and Approximate Convex Decomposition (ACD), which are evaluated and compared based on their collision detection performances. An exact convex decomposition algorithm, named as ConvexFT, is also proposed and analyzed in this paper. Finally the performance of the three existing methods and the ConvexFT proposed approach are compared in order to assess which model representation algorithm is best suited for haptic-virtual assembly tasks.

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