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Motion control for flexible link manipulators will have a great influence on their overall performance. Conventional control systems have the problem that they cannot compensate for the presence of uncertainty due to a variety of factors such as a change in the system itself-payload variations, degradation and modelling uncertainty. In addition, the underdamped structure of these systems entails motion-induced transient deflection and residual vibration. On the contrary, adaptive control, in particular Model Reference Adaptive Control (MRAC), has therefore been proposed to handle problems of this type dealing with other systems such as cranes, steering stability control for ground vehicles, airplanes and so on. This study presents a review and discussion on the MRAC and some individual issues of MRAC for these flexible link manipulators are addressed to specify: the state tracking error, the limitation of the adaptation values corresponding to the control gains and the control effort. Dealing with the last one, this work proves that shaping the command input to a Model Reference Adaptive Control (IS-MRAC) reduces the control effort necessary for the plant to follow the reference model and also mitigates the detrimental effects of flexibility. The IS-MRAC is implemented in a Single-Link Flexible Manipulator whose natural frequencies, experimentally and analytically estimated using the Transfer Matrix Method plus symbolic computation, vary significantly depending on payload mass and position. To this structured or parametric uncertainty, the proposed Lyapunov control law using the states associated with the low mode is designed for asymptotic stability and accommodates correctly. The state tracking, vibration suppression and control effort reduction performances of the proposed IS-MRAC combined controller are analysed via numerical simulations and experiments. [ABSTRACT FROM AUTHOR]

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Vibration signals are a widely used technique for machine monitoring and fault diagnostics. However, it is necessary to select a suitable pattern that represents the condition of the machine. Wavelet Packet Transform (WPT) provides a high potential for pattern extraction. Several factors must be selected and taken into account in the wavelet transform application such as the level of decomposition, the suitable mother wavelet, and which frequency bands (obtained from the decomposition process) contain the necessary information for the diagnosis system. The selection of the parameters commented above is a complex task that depends on many factors. Most of the works found in the literature select these factors based on experience, graphical methods, or trial and error methods. In this work, a method based on the relative wavelet energy is developed in order to automatically select the parameter defined by the WPT. The selection allows for the efficient extraction of the most suitable patterns for a later classification and fault detection process. In order to prove the soundness of the method proposed, a Jeffcott rotor model with four crack levels will be developed, and the vibratory signals provided by this model will be used for the monitoring condition. [ABSTRACT FROM AUTHOR]

As a result of market globalization and increasing demand of products, companies have to improve their production processes and modify their operations to adjust to changes and be competent. This context is being steadily accentuated in the manufacturing sector, where many companies are conducting research on formative methods that allow engineers and operators, whether newly hired or transferred from other plants of the company, reach the standard production level quickly, thereby achieving and maintaining the necessary level of market competitiveness. In this paper, we introduce a case of formative software development at the Robert Bosch Gasoline Systems Company (Aranjuez, Spain) that has just begun the implementation of a Lean Transformation project, performed in order to standardise production according to their global benchmarks and thereby improve the productivity of the filter manufacturing lines. During a previous evaluation of production lines, we decided that cultivating employees based on parameters of machine management and the knowledge of their influence on the final product is the key area of concern since it significantly influences production losses and the productivity indicator of each line. In order to achieve this, we focused on the production of diesel filters; a master's student at the company was designated to analyse various formative methods. Finally, we developed a decision-making simulator of the manufacturing parameters. The resultant software was implemented in Visual Basic and Excel, which allowed the integration of the tool in the company's work culture. The simulator was then tested with plant employees, observing the general improvement of knowledge about the production processes of diesel filters. Finally, it was implemented at the factory. We realised that time reduction on technical and on organizational losses led to an increase in the productivity. [ABSTRACT FROM AUTHOR]

In recent years, engineering colleges have started to integrate service-learning projects into many of their required courses. In the literature, there are many important definitions for service-learning pedagogy, including reciprocity, reflection, coaching and community projects. This paper presents a service-learning pedagogy implementation program for educating engineering undergraduates to solve real-world problems. Three project models for mechanical engineering, ranging from a single semester to a full calendar year, form the basis for the analyses presented. Finding appropriate community partners and projects are critical for a successful experience for all involved parties. From the results of this analysis, it is possible to conclude that, through these projects; students acquired and applied the competencies in the defined curriculum. [ABSTRACT FROM AUTHOR]