Papers by Author: Kazem Abhary

Abstract: Due to the increasing demand for environmentally friendly products and growing concern for green industry, environmental evaluation and environmental performance have become important measures of business and manufacturing industry. The main purpose of this evaluation is to evaluate, review, monitor and check environmental performance and compare it with its environmental performance criteria. The integration of quantitative and qualitative measurement is needed to facilitate the design of environmental performance evaluation. This research presents the design of environmental performance evaluation by using fuzzy expert system. Expert knowledge is acquired to develop the fuzzy rules. The proposed design is flexible enough to be modified and used with the different criteria.

Abstract: Tolerance parameters have different effects on robot accuracy. Therefore, it is better to tighten the tolerances of the factors that have statistically significant effect on robot accuracy and widen the tolerances of insignificant ones. By doing so, one not only achieves the given robot accuracy but also reduces manufacturing costs. Objective of this paper is to present an approach used to determine statistical significance of each tolerance parameter of robot manipulator on robot accuracy which can assist robot designers in making decisions regarding tolerance design. In this paper, a comprehensive model of industrial robot manipulator capable of carrying out various applications is developed and computer simulated. Then Taguchi’s Tolerance Design Experiment is applied to determine the statistical significances of the tolerances on robot accuracy. The approach is illustrated by a case study dealing with 6-DOF PUMA 560 robot manipulator.

Abstract: Lean six-sigma methodology focuses on continuous improvement approach with an emphasis on improving the product quality and reducing waste. Recent studies of lean six-sigma methodology indicated that this methodology commonly focus on four areas of performance namely quality, cost time and service. In this paper, an environmental performance is proposed into lean six-sigma methodology. An environmental performance needs to be integrated into lean six-sigma as a new paradigm of lean six-sigma methodology to achieve overall competitiveness of product.

Abstract: The primary purpose of this study is to develop a genetic algorithm based computer-aided roll pass optimal design (CAROD) system to support the generalized roll pass design for rod rolling, where the final products are round bars with different sizes. The system was developed to minimize the number of roll passes, decrease the trails and errors in industry, as well as extend the work range of multi-pass rolling systems for rod rolling. Parametric equations were established for geometrical modeling and graphic plotting, which can realize to the parametric transformation for roll pass design and optimization. A methodology based on a hybrid model was proposed to choose passes with different profiles for the multi-pass rod rolling system. In addition, an improved genetic algorithm (IGA) was employed for the optimization of roll passes. A MATLAB program was designed to achieve all these objectives. To reduce the complexity and computational burden of the software, some reliable empirical formulas were applied in this system. Finally, the proposed approach has been applied in a rod rolling system; through simulation and comparison of results against analytical solutions, numerical analysis and experimental data presented by other researchers, it was found that this system is reliable, effective and easier to use.

Abstract: Hot steel rolling is amongst the most important industrial techniques because of huge amount of consumed resources, immense environmental impact, and the significance and enormous quantity of long products. Criteria for improving rolling operations include process efficiency, resource consumption, system reliability, product quality and ergo-ecological sustainability. There is an increasing availability of information within and beyond the domain of forming by rolling. With advances in computerised information processing, it becomes apparent that further progress is to be sought in intelligently combining the strategies and theories developed in differing disciplines. The key to optimising rolling systems is to be found in hybrid models. This approach calls for utilising cross-disciplinary knowledge, including a selection amongst methods such as stochastic, fuzzy and genetic modelling, process control and optimisation as well as supply chain and maintenance management. Evidence obtained by experiments using small-scale chemo-physical modelling encourages the use laboratory rolling for preliminary validations. Research strategy is conceptualised on the basis of a knowledge-based hybrid model. The sample space for this model is constituted by the rolling passes translated into the form of vectors. An example of a rolling pass translation into the vector form is presented.