Virtual reality for fixture design and assembly

Due to today's heavy, growing competition environment, manufacturing companies have to develop and employ new emerging technologies to increase productivity, reduce production costs, improve product quality, and shorten lead time. The domain of Virtual Reality (VR) has gained great attention during the past few years and is currently explored for practical uses in various industrial areas e.g. CAD, CAM, CAE, CIM, CAPP and computer simulation etc. Owing to the trend towards reducing lead time and human effort devoted to fixtureplanning, the computerization of fixture design is required. Consequently, computer aided fixture design (CAFD) has become an important role of computer aided design/manufacture (CAD/CAM integration. However, there is very little ongoing research specially focused on using the VR technology as a promising solution to enhance CAFD systems' capability and functionality. This thesis reviews the possibility of using interactive Virtual Reality (VR) technology to support the conventional fixture design and assembly process. The trend that the use of VR benefits to fulfil the optimization of fixture design and assembly in VE has been identified and investigated. The primary objectives were to develop an interactive VR system entitled Virtual Reality Fixture Design & Assembly System (VFDAS), which will allow fixture designers to complete the entire design process for modular fixtures within the Virtual Environment (VE) for instance: Fixture element selection, fixture layout design, assembly, analysis and so on. The main advantage of VFDAS is that the VR system has the capability of simulating the various physical behaviours for virtual fixture elements according to Newtonian physical laws, which will be taken into account throughout the fixture design and evaluation process. For example: gravity, friction, collision detection, mass, applied force, reaction force and elasticity. Almost the whole fixture design and assembly process is achieved as if in the real physics world, and this provides a promise for computer aided fixture design (CAFD) in the future. The VFDAS system was validated in terms of the collision detection, rendering speed, friction, mass, gravity, applied force, elasticity and toppling. These simulation results are presented and quantified by a series of simple examples to show what the system can achieve and what the limitations are. The research concluded VR is a useful technology and VFDAS has potential to support education and application for fixture design. There is scope for further development to add more useful functionality to the VFDAS system

Virtual reality for fixture design and assembly

Due to today's heavy, growing competition environment, manufacturing companies have to develop and employ new emerging technologies to increase productivity, reduce production costs, improve product quality, and shorten lead time. The domain of Virtual Reality (VR) has gained great attention during the past few years and is currently explored for practical uses in various industrial areas e.g. CAD, CAM, CAE, CIM, CAPP and computer simulation etc. Owing to the trend towards reducing lead time and human effort devoted to fixtureplanning, the computerization of fixture design is required. Consequently, computer aided fixture design (CAFD) has become an important role of computer aided design/manufacture (CAD/CAM integration. However, there is very little ongoing research specially focused on using the VR technology as a promising solution to enhance CAFD systems' capability and functionality. This thesis reviews the possibility of using interactive Virtual Reality (VR) technology to support the conventional fixture design and assembly process. The trend that the use of VR benefits to fulfil the optimization of fixture design and assembly in VE has been identified and investigated. The primary objectives were to develop an interactive VR system entitled Virtual Reality Fixture Design & Assembly System (VFDAS), which will allow fixture designers to complete the entire design process for modular fixtures within the Virtual Environment (VE) for instance: Fixture element selection, fixture layout design, assembly, analysis and so on. The main advantage of VFDAS is that the VR system has the capability of simulating the various physical behaviours for virtual fixture elements according to Newtonian physical laws, which will be taken into account throughout the fixture design and evaluation process. For example: gravity, friction, collision detection, mass, applied force, reaction force and elasticity. Almost the whole fixture design and assembly process is achieved as if in the real physics world, and this provides a promise for computer aided fixture design (CAFD) in the future. The VFDAS system was validated in terms of the collision detection, rendering speed, friction, mass, gravity, applied force, elasticity and toppling. These simulation results are presented and quantified by a series of simple examples to show what the system can achieve and what the limitations are. The research concluded VR is a useful technology and VFDAS has potential to support education and application for fixture design. There is scope for further development to add more useful functionality to the VFDAS system

AirConstellations: In-Air Device Formations for Cross-Device Interaction via Multiple Spatially-Aware Armatures

AirConstellations supports a unique semi-fixed style of cross-device interactions via multiple self-spatially-aware armatures to which users can easily attach (or detach) tablets and other devices. In particular, AirConstellations affords highly flexible and dynamic device formations where the users can bring multiple devices together in-air - with 2-5 armatures poseable in 7DoF within the same workspace - to suit the demands of their current task, social situation, app scenario, or mobility needs. This affords an interaction metaphor where relative orientation, proximity, attaching (or detaching) devices, and continuous movement into and out of ad-hoc ensembles can drive context-sensitive interactions. Yet all devices remain self-stable in useful configurations even when released in mid-air. We explore flexible physical arrangement, feedforward of transition options, and layering of devices in-air across a variety of multi-device app scenarios. These include video conferencing with flexible arrangement of the person-space of multiple remote participants around a shared task-space, layered and tiled device formations with overview+detail and shared-to-personal transitions, and flexible composition of UI panels and tool palettes across devices for productivity applications. A preliminary interview study highlights user reactions to AirConstellations, such as for minimally disruptive device formations, easier physical transitions, and balancing "seeing and being seen"in remote work

The reverse guillotine tribometer for evaluation of sliding wear of Additive Manufactured fixtures

Purpose – The purpose of this paper is to present a custom-built tribometer that mimics the wear of additive manufactured fixtures used in inspection of sheet metal components. Design/methodology/approach – Referring to the inspection of sheet metal parts, the fixture undergoes sliding wear during loading and unloading phases of the quality control operation. A new wear test is proposed to mimic the actual wearing conditions of the fixtures because the standards are deemed insufficient. In the tribometer, a cylindrical Alumide cantilever beam is made to slide back and forth inside a slightly bigger hole cut into a nickel-plated steel sheet. The sheet is spring loaded such that it applies a force on the specimen. The wear on the beam is measured after every 500 cycles of the beam motion. Findings – Results of some first test trials are reported to evaluate the durability of Alumide fixtures fabricated by selective laser sintering. The results are also compared to those obtained for a machined fixture made of an Al-Cu alloy. Practical implications – The proposed wear test estimates the life time of additive manufactured fixtures in terms of numbers of inspected components. The test can be extended to different materials to compare their durability. Originality/value – Today, the fabrication of custom fixtures by means of additive manufacturing technologies is a reality in many manufacturing industries. The advantage of using those production technologies for custom fixtures is well assessed in literature in terms of manufacturing times and costs, whereas little attention was given to the life time and wear behaviour of fabricated fixtures. For its practical implication, the fixture durability is indeed very important for manufactures

An integrated computer-aided modular fixture design system for machining semi-circular parts

Productivity is one of the most important factors in manufacturing processes because of the high level of market competition. In this regard, modular fixtures (MFs) play an important role in practically improving productivity in flexible manufacturing systems (FMSs) due to this technology using highly productive computer numerical control (CNC) machines. MFs consist of devices called jigs and fixtures for accurately holding the workpiece during different machining operations. The design process is complex, and traditional methods of MF design were not sufficiently productive. Computer-aided design (CAD) software has rapidly improved as a result of the development of computer technology, and has provided huge opportunities for modular fixture designers to use its 3D modelling capabilities to develop more automated systems. Computer-aided fixture design (CAFD) systems have become automated by the use of artificial intelligence (AI) technology. This study will investigate the further improvement of automated CAFD systems by using AI tools. In this research, an integrated CAFD is developed by considering four main requirements: · a 3D model of the workpiece, · an expert system, · assembly automation of MFs, · an efficient feature library. The 3D model is an important factor that can provide the appropriate specification of the workpiece; SolidWorks is used the CAD environment for undertaking the 3D modelling in this study. The expert system is applied as a tool to make right decisions about the CAFD planning process, including locating and clamping methods and their related element selection. This helps achieve a feasible fixture design layout. SolidWorks API and Visual Basic programming language are employed for the automating and simulation of the assembly process of MFs. A feature library of modular fixture elements is constructed as a means to simplify the fixture design process

Automating Virtualization of Machinery for enabling efficient Virtual Engineering Methods

Virtual engineering as a new working method in product development should make it much easier to validate the development progress and facilitate team communication. Work steps are brought forward and start with the virtual components instead of real ones. To validate mechanical and electrical CAD as well as programming, automated virtualization systems should create the virtual twin of the machine at the push of a button. For this purpose, generic intelligence is added to enable complex interactive virtual models that can be used for training, monitoring and many other applications. Advanced applications are for example training and support applications, especially in combination with augmented reality and remote collaboration. We propose a system that combines virtual reality, virtual engineering and artificial intelligence methods for the product development process. Geometry analysis algorithms are used to process mechanical CAD data and thus, for example, to automatically parameterize kinematic simulations. In combination with electrical CAD data and the simulations of electric circuits as well as the original machine program allow simulating the behavior of the machine and the user interaction with it. This article will describe the virtualization method in detail and present various use-cases in special machine construction. It will also propose a novel method to use causal discovery in complex machine simulations

The evaluation of a novel haptic machining VR-based process planning system using an original process planning usability method

This thesis provides an original piece of work and contribution to knowledge by creating a new process planning system; Haptic Aided Process Planning (HAPP). This system is based on the combination of haptics and virtual reality (VR). HAPP creates a simulative machining environment where Process plans are automatically generated from the real time logging of a user’s interaction. Further, through the application of a novel usability test methodology, a deeper study of how this approach compares to conventional process planning was undertaken. An abductive research approach was selected and an iterative and incremental development methodology chosen. Three development cycles were undertaken with evaluation studies carried out at the end of each. Each study, the pre-pilot, pilot and industrial, identified progressive refinements to both the usability of HAPP and the usability evaluation method itself. HAPP provided process planners with an environment similar to which they are already familiar. Visual images were used to represent tools and material whilst a haptic interface enabled their movement and positioning by an operator in a manner comparable to their native setting. In this way an intuitive interface was developed that allowed users to plan the machining of parts consisting of features that can be machined on a pillar drill, 21/2D axis milling machine or centre lathe. The planning activities included single or multiple set ups, fixturing and sequencing of cutting operations. The logged information was parsed and output to a process plan including route sheets, operation sheets, tool lists and costing information, in a human readable format. The system evaluation revealed that HAPP, from an expert planners perspective is perceived to be 70% more satisfying to use, 66% more efficient in completing process plans, primarily due to the reduced cognitive load, is more effective producing a higher quality output of information and is 20% more learnable than a traditional process planning approach