Haptically enabled interactivity and immersive virtual assembly

Virtual training systems are attracting paramount attention from the manufacturing industries due to their potential advantages over the conventional training practices such as general assembly. Within this virtual training realm for general assembly, a haptically enabled interactive and immersive virtual reality (HIVEx) system is presented. The idea is to imitate real assembly training scenarios by providing comprehensive user interaction as well as by enforcing physical constraints within the virtual environment through the use of haptics technology. The developed system employs a modular system approach providing flexibility of reconfiguration and scalability as well as better utilization of the current multi-core computer architecture. The user interacts with the system using haptics device and data glove while fully immersed into the virtual environment with depth perception. An evaluation module, incorporated into the system, automatically logs and evaluates the information through the simulation providing user performance and improvements over time. A ruggedized portable version of the system is also developed and presented with full system capabilities allowing easy relocation with different factory environments. A number of training scenarios has been developed with varying degree of complexity to exploit the potential of the presented system. The presented system can be employed for teaching and training of existing assembly processes as well as the design of new optimised assembly operations. Furthermore, the presented system can assist in optimizing existing practices by evaluating the effectiveness and the level of knowledge transfer involved in the process. Within the aforementioned conceptual. framework, a working prototype is developed.

Haptically enable interactive virtual assembly training system development and evaluation

Virtual training systems are attracting paramount attention from the manufacturing industries due to their potential advantages over the conventional training practices. Significant cost savings can be realized due to the shorter times for the development of different training-scenarios as well as reuse of existing designed engineering (math) models. In addition, use of computer based virtual reality (VR) training systems can shorten the time span from computer aided product design to commercial production due to non-reliance on the hardware parts for training. Within the aforementioned conceptual framework, a haptically enabled interactive and immersive virtual reality (HIVEx) system is presented. Unlike existing VR systems, the presented idea tries to imitate real physical training scenarios by providing comprehensive user interaction, constrained within the physical limitations of the real world. These physical constrains are imposed by the haptics devices in the virtual environment. As a result, in contrast to the existing VR systems that are capable of providing knowledge generally about assembly sequences only, the proposed system helps in cognitive learning and procedural skill development as well, due to its high physically interactive nature.

Haptics interface for modelling and simulation of flexible cables

Virtual reality systems are becoming a must for product and process design, training practices and ergonomic analysis in many manufacturing industries. The automotive sector is considered to be the leader in applying virtual reality (VR) solutions for real-world, non-trivial, problems. Although, a number of commercial 3D engineering tools for digital mockups exist, most of them lack intuitive direct manipulation of the digital mockups. The majority of these 3D engineering tools are constrained to the interaction mainly with rigid objects which is just half the story. To bridge this gap, we have developed a haptics interface for modelling and simulation of flexible objects. The graphical and haptic user interface developed allows the creation of multiple one dimensional (1D) flexible objects, such as hoses, cables and harnesses. The user is required to provide the mechanical properties of the material such as Young's modulus, Poisson's ratio, material density, damping factors, as well as dimensional properties such as length, and inner and outer diameters of the flexible object. Flexilution solver is employed to estimate and simulate the dynamic behaviour of flexible objects in response to external user interaction, whereas Nvidia's generic physics engine is used to simulate the behaviour of rigid objects. A generic communication interface is developed to accommodate a variety of devices without the reconfiguration of the simulation platform.

Grain refinement in titanium alloys through thermomechanical processing

Qi developed a novel thermomechanical processing route for the grain refinement of titanium alloys. This leads to a well-balanced superior mechanical property, which is vital for modern air transport. The outcomes of this project are prospective to enhance titanium application and the long-term viability of Australian resources and manufacturing industries.

Development of a dynamic surface roughness monitoring system based on artificial neural networks (ANN) in milling operation

Dynamic surface roughness prediction during metal cutting operations plays an important role to enhance the productivity in manufacturing industries. Various machining parameters such as unwanted noises affect the surface roughness, whatever their effects have not been adequately quantified. In this study, a general dynamic surface roughness monitoring system in milling operations was developed. Based on the experimentally acquired data, the milling process of Al 7075 and St 52 parts was simulated. Cutting parameters (i.e., cutting speed, feed rate, and depth of cut), material type, coolant fluid, X and Z components of milling machine vibrations, and white noise were used as inputs. The original objective in the development of a dynamic monitoring system is to simulate wide ranges of machining conditions such as rough and finishing of several materials with and without cutting fluid. To achieve high accuracy of the resultant data, the full factorial design of experiment was used. To verify the accuracy of the proposed model, testing and recall/verification procedures have been carried out and results showed that the accuracy of 99.8 and 99.7 % were obtained for testing and recall processes.

Force reflection distribution of haptic devices

Haptically enabled virtual reality systems facilitate rapid and low cost testing for process design, training practices and ergonomic analysis in many manufacturing industries, particularly automotive and aerospace. In this work we design a validation framework to validate the dynamic forces displayed by haptic display devices using a robot arm equipped with a force sensor. The validation framework is completely autonomous to ensure unbiased characterization. Measured force magnitude and the direction of the sensed force vector are the main criteria used in this work.

Additive manufacturing in the cycling industry: mainstream or gimmick?

INTRODUCTION. Additive manufacturing (AM) for various industries has been trailed, prototyped and used in limited production runs (Gibson, 2015). But considering additive manufacturing with metallic materials has been around for over 15 years the penetration into an industry such as cycling that values customisation and progressive design techniques has been quite limited. This case study looks at the potential of and why additive manufacturing has not progressed from concept development and prototyping into production and mainstream. Selective Laser Melting (SLM) additive manufacturing systems mainly use Stainless Steel 316 (SS316) and Titanium 6Al.4V (Ti64) as a baseline material; both these materials are extremely common in the custom and high volume bike industries. For the purposes of this article we will focus on smaller custom bike manufacturers who are typically more agile and open to high levels of customisation in their products. The study finds that whilst a high number of companies will experiment and prototype with additive manufacturing there is little evidence that the design and development process translates to ongoing production for sale to the consumer, this could be due to knowledge of design and fabrication techniques.

What firm characteristics determine women's employment in manufacturing? evidence from Bangladesh

The purpose of this paper is to investigate the principal determinants of women's employment in the manufacturing sector of Bangladesh using a firm-level panel data from the World Bank's "Enterprise Survey" for the years 2007, 2011 and 2013. The paper sheds light on the demandside factors, mainly firm-level characteristics, which also influence this decision. Design/methodology/approach - The authors estimate a fractional logit model to model a dependent variable that is limited by zero from below and one from above. Findings - The results indicate that firm size, whether medium or large, and firms' export-oriented activities, have an important impact on women's employment in the manufacturing sector in Bangladesh. Moreover, the authors find that women are significantly more likely to work in unskilledlabour- intensive industries within the manufacturing sector. Research limitations/implications - The research is limited to Bangladesh; however, much of the evidence presented here has implications that are relevant to policymakers in other developing countries. Practical implications - The study identifies factors that affect female employment, that is, where the main constraints to increase female labour force participation. The study focuses on the demand-side factors, which has been somewhat neglected in recent years. As such, it has practical policy implications. Social implications - Focusing on female employment in Bangladesh also sheds light on the nexus between labour market opportunities and social change within a country that is characterised by extreme patriarchy, which has wide-reaching implications. Originality/value - This is an original and comprehensive paper by the authors.