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One of the main objectives when designing welded products is to reduce strains and deformations. Strains can cause excessive angular distortion. This results in a welded product that does not meet acceptable tolerances. The geometry of the weld bead (height and width) depends on the input parameters (speed, voltage and current), and provides the welded joint with strength and quality. As welded products become increasingly complex, deformations become more difficult to predict as they depend greatly on the welding sequence. This paper shows how a combination of the Finite Element Method, Genetic Algorithms and Regression Trees may be used to design and optimize complex welded products. Initially, Artificial Neural Networks and Regression Trees that are based on heuristic methods and evolutionary algorithms were used in predicting the weld bead geometry according to the input parameters. Then, thermo-mechanical Finite Element models were created to obtain the temperature field and the angular distortion using the weld bead geometry that the best predictive models generated. Finally, optimization techniques that are based on Genetic Algorithms were used to validate these Finite Element models against experimental results, and to subsequently find the optimal welding sequence to use in the manufacture of complex welded products.

The robotic welding manufacturing of metal parts is a very important process, especially in heavy industries such as shipbuilding, oil and gas, automotive, and aerospace. There is a great variety of different techniques for manufacturing by robotic welding, and the welding operations are always in a constant process of evolution, as any advance can be significant to avoid defects during the welding process. Although a great deal of research work has been carried out in recent years, thanks to which results and reviews have been presented on this subject, the main aim of this publication is to define and review works that show the advances in the main inspection, modeling, monitoring, and automated operations during the welding process to avoid, or predictively identify, any possible defect in order to obtain an optimum degree of quality in the welding.

Traditionally, design activities cover a wide range of interrelated activities: mechanical design, industrial design, electronic design and civil design, to name a few. Pugh’s Total Design method consists of several core activities that complement and influence each another. Core activities are the basis of the development of the product design specification, the conceptual design, the detailed design, the product’s manufacture and final product sales. A systematic approach is proposed in this article to convert design requirements into an optimal design concept choice. The approach is based on Pugh’s method to design a new electromagnetic servo brake with antilock braking system function. The product design specifications were obtained by the functional analysis method that Tassinari proposed. Also, the Pugh controlled convergence method was used to select the best conceptual design. A combination of the finite element method and multi-objective optimization based on genetic algorithms was used in the detail phase to obtain the optimal geometry of the servo that was designed, while maximizing the braking force and minimizing the current supplied by the battery and the weight of the assembly. The close agreement between the experimental results obtained suggests that Pugh’s Total Design method, combined with the functional analysis method, the Pugh controlled convergence method, the finite element method and genetic algorithms, may be used successfully to design and optimize any electromechanical device.

There are many mechanical and/or electrical energy storage devices nowadays which can be mounted on standard bicycles. The current trend regarding bicycle energy storage devices is to develop and improve electrical and electronic systems that can ease transportation. However, this paper shows the design process of a purely mechanical energy storage device, with no electrical components, which instead aims to entertain the user, producing a stimulus related to speed and physical exertion. The mechanical device has been designed according to an aspect or fashion known as steampunk, so that the mechanical elements forming the device (springs and spur gears) are visible to the user. The storage and discharge of energy are only produced by the user. In order to charge the device, after reaching an appropriate speed, the user uses the pedals in reverse motion. Alternatively, the mechanism can also be charged with a controlled braking system by actuating on a crank. The design process was based on the total design of Pugh and the AHP and QFD techniques.