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This paper proposes a fault detection and isolation (FDI) scheme for a wind turbines subject to actuator faults in both the pitch system and the drive train system. The proposed scheme addresses fault detection and isolation problems using a fault estimation approach. The proposed approach considers the use of a particular class of sliding mode observers (SMOs) designed to maintain the sliding motion even in the presence of actuator faults. The fault detection problem is solved by reconstructing the actuator faults through an appropriate analysis of the nonlinear output error injection signal, which is required to keep the SMO in a sliding motion. To ensure accurate fault reconstruction, only two conditions are required, namely that the faults are bounded and they meet the matching condition. A scheme based on a bank of SMOs is proposed to solve the fault detection and isolation problem in the pitch system. For the drive train system, a scheme using only one SMO is proposed. The performance of the proposed FDI scheme is validated by using a wind turbine benchmark model subjected to several actuator faults. Normalized root mean square error (NRMSE) analysis is performed to evaluate the accuracy of the actuator fault estimations.

A fault detection and isolation (FDI) approach based on nonlinear sliding mode observers for a wind turbine model is presented. Problems surrounding pitch and drive train system FDI are addressed. This topic has generated great interest because the early detection of faults in these components allows avoiding irreparable damage in wind turbines. A fault diagnosis strategy using nonlinear sliding mode observer banks is proposed due to its ability to handle model uncertainties and external disturbances. Unlike the reported solutions, the solution approach does not need a priori knowledge of the faults and considers system uncertainty. The robustness to disturbances, uncertainties, and measurement noise is shown in the dynamic of the generated residuals, which is sensible to only one kind of fault. To show the effectiveness of the proposed FDI approach, numerical examples based on a wind turbine benchmark model, considering closed loop applications, are presented.

Lack of water in Mexico City and its peri-urban area has been an increasingly worrying matter in the last few years and has been addressed through multiple government and NGO initiatives such as supplemental delivery via water trucks, rainwater harvesting, intermittence in water services and pipeline network maintenance. However, the rapid and unstructured development of the urban spot has exacerbated the problem, rendering these solutions ineffective. Due to the complexity of the problem, solutions may be more impactful if they focus on fixing or creating effective interactions among the elements of the system — interactions in which the main element is the user. This paper presents a design proposal created from the observations made in Mexico City. Design Thinking was used by understanding the users’ needs and the interactions between the agents through three main phases: Approach and definition of the problem, Prototyping stage and Final proposal explanation. The proposal and research results could be used and extrapolated to other cities and communities around the world, as water availability and quality are a global challenge and can be tackled in similar ways.

Mobility as a key element in the dynamics of any city, a development potentiator and resilience factor, is vital for transforming megalopolis into Smart Cities. However, due to numerous elements that interact within urban mobility, solutions are hard to accomplish. Since public transport is crowded in large cities, the process for buying a ticket must be shortened as much as possible. However, even when machines are used for selling tickets in the Mexican public transportation system, not the entire population has access to the variety of payment methods other than the use of cash. Moreover, there is a wide mixture of others who also interact with the machine such as those involved in maintenance, surveillance, and cash collectors. Based on the information gathered and the steps from the user centered design methodology, a design proposal for improving the interaction was conceived. This paper presents the process that was followed for designing a Ticket Vending Machine (TVM) for Mexico City’s public transport, through which human-machine interaction was made simpler and easier to follow compared to previous TVMs and thus refining a key interaction in mobility for a more efficient transport system. The results and the design proposal could be useful for tackling human-machine interaction concerning other products such as automated teller machines, parking ticket machines and other TVMs for public transport in other cities or countries with a similar panorama. The implementation of the user-centered design methodology involves the users at each step of the process to understand and tackle their needs when prototyping and testing are conducted. The methodology boosts the innovation and allows faster implementation of ideas, due to its flexibility throughout the iterative process, which is an advantage compared to linear methodologies where feedback is gathered until the end of the process and not during the development of new products and services.

Additive manufacturing (AM) is defined as the process of joining materials to make objects from 3D model data, usually layer upon layer, in contrast to subtractive or forming manufacturing methodologies. In studies of energy consumption in AM systems reported in the literature, the electric energy consumed by different technologies was measured directly in the main electrical supply wires of the machines, which does not represent the process energy consumption, because there are peripheral devices that do not have an influence on the process. In order to generate a better approach to the energy consumption of the AM process, this paper presents a proposal to measure the energy consumption directly in the system stage in which the AM processes are performed: preparing the material for extrusion, deposition, selection, gluing, curing, and so on, obtaining the geometry of a layer defined by an area with a certain thickness, and carrying out bonding between the layers to form a solid part. Because the combination of material and manufacturing processes determine the mechanical properties of a built part and because different materials and processes could be used to obtain these mechanical properties with different energy consumption values, the authors suggest mathematical models for three AM processes (material extrusion, vat photopolymerization, and material jetting) which predict the energy consumption and then compare the values with their experimental results, obtaining a difference of less than 10%, and find the parameters which define the differences in energy consumption among the processes.

Theoretical knowledge is important in all disciplines, but practical knowledge is of utmost importance in many of them, such is the case in engineering, medicine, and architecture. In most of these majors’ instructors focus more on the theoretical area and set aside the practical one. That is why it is important to develop educational tools to improve students’ practice. Medical students at the Universidad Nacional Autónoma de México were our case of study since we noticed a lack of practical knowledge during their second year at University. In this paper, we present a design methodology of a toy for the students of medicine to exercise and improve their manual precise movements and motor sequencing skills, in order to improve their practical abilities by using it. This methodology emphasizes the importance of specific movements that surgeons do while they perform basic surgical procedures, intending to imitate them when they use the toy. Therefore, procedures like cutting, suturing, exposure, among others were performed by a surgeon, recorded, and analyzed. As a result, it was observed that some movements were repeated in most of the procedures. Based on this, a device was designed so that the user may be able to repeat the movements following a series of audiovisual instructions as a game. To validate its efficiency manual precision tests were used to compare the individual students’ improvement before and after using it. Once the device was built as a toy, 12 second-year medical students took the precision tests, the measured variable was the time they used to complete both tests. Furthermore, they practiced with the toy for 10 days, 6 minutes per day. On the last day, after using it, each student performed the precision tests once again to obtain a quantitative value of their improvement. The time spent by each student to perform the first precision tests were compared to the last after using the toy. The results showed that the execution time was reduced by an average of 53.75 seconds in the first precision test and 45 seconds in the second. This indicates that the use of the toy allows students to improve their manual precision skills, affecting the execution time of tasks that require accurate manual precision. Also, it was observed that the methodology developed could be applied and extrapolated to other disciplines such as engineering, in order to develop similar toys or devices that could enhance manual skills.

El tratamiento con clozapina se encuentra reservado para aquellos pacientes con trastornos psicóticos especialmente graves y con mala respuesta a tratamientos habituales. Por otro lado, se ha hablado de su eficacia para prevenir conductas suicidas (1) así como acción para el control del consumo de tóxicos (2). OBJETIVOS: Estudiar la presencia de patología dual en paciente con trastorno mental grave (TMG) Analizar la respuesta clínica de los mismos tras el inicio del tratamiento con clozapina MÉTODO: Recogemos una muestra de los 31 pacientes que reciben tratamiento con clozapina en el último año de nuestra área de referencia (compuesta por unas 64.000 personas mayores de 16 años). Se realiza una revisión de la historia clínica de todos los pacientes que se encuentran sometidos a este tratamiento. Diagnósticos de la muestra : Esquizofrenia 25 (80%), trastorno de ideas delirantes (13%), Trastorno Esquizoafectivo (6%). RESULTADOS: La muestra compuesta por 31 pacientes: 9 mujeres (29%), 22 hombres (71%). Recibieron diagnóstico de patología dual un 32% no habiendo ningún caso entre mujeres y representado en 45% de los hombres. Además de clozapina se encuentran con tratamiento inyectable de larga duración el 55%. El análisis del número de ingresos y consumo de tóxicos antes y después del inicio con clozapina muestra diferencias estadísticamente significativas. El número escaso de pacientes no permite extraer datos definitivos sobre la autolisis.. CONCLUSIONES Los pacientes TMG presentan mejor control en el consumo de tóxicos tras el inicio de tratamiento con clozapina. La clínica psicótica mejora como releja la reducción drástica del número de ingreso que presentan estos pacientes ya que la mayoría de ellos no han presentado ingresos en los 5 últimos años. Bibliografía: 1. Serfaty, E. Patología Dual. Comorbilidad trastorno psiquiátrico y consumo de sustancias psicoactivas. 2. Núñez Dominguez, LA. Uso de neurolépticos atípicos en esquizofrénicos consumidores de cannabis.

Very commonly, a mechanical workpiece manufactured industrially includes more than one machining operation. Even more, it is a common activity of programmers, who make a decision in this regard every time a milling and drilling operation is performed. This research is focused on better understanding the power behavior for face milling and drilling manufacturing operations, and the methodology followed was the design of experiments (DOEs) with the cutting parameters set in combination with toolpath evaluation available in commercial software, having as main goal to get a predictive power equation validated in two ways, linear or nonlinear, and understanding the energy consumption and the quality surface in face milling and final diameter in drilling. The results show that it is possible to find difference in a power demand of 1.52 kW to 3.9 kW in the same workpiece, depending on the operations (face milling or drilling), cutting parameters, and toolpath chosen. Additionally, the equations modelled showed acceptable values to predict the power, with p values higher than 0.05 which is the significance level for the nonlinear and linear equations with an R square predictive of 98.36. Some conclusions established that optimization of the cutting parameters combined with toolpath strategies can represent an energy consumption optimization higher than 0.21% and the importance to try to find an energy consumption balance when a workpiece has different milling operations.

Los intentos de suicidio son con una de las causas de urgencias psiquiátricas que más impacto producen en la sociedad en general y de los servicios sanitarios en particular. OBJETIVOS: Estudiar el consumo de tóxicos de los pacientes con intento de suicidio. Estudiar la gravedad de los intentos de suicidio según la presencia de tóxicos. MÉTODO: Se analizan todos los intentos de suicidio que han tenido lugar durante un año atendidos en el Servicio de Urgencias de Psiquiatría del Hospital Provincial de Ponteve(N=149). El 58,3% de los pacientes son mujeres y el 41,4% hombres. La edad media de la muestra es 41,72+/-16,55. Se recoge el consumo actual de los pacientes según los datos de la historia clínica y el análisis de tóxicos en orina. La gravedad del intento es analizado mediante el cuestionario SAD Persons y la Intencionalidad Suicida de Beck. RESULTADOS: Presentan consumo de tóxicos el 41% de la muestra. El 18,3% presentan un consumo patológico de alcohol, el 14,3% son policonsumidores, un 8% presentan consumo activo y habitual de cannabinoides, un 4,9% cocaína y 1,1% opiáceos. Los pacientes con consumo de tóxicos presentan diferencias estadísticamente significativas según el número de intentos de suicidio previos respecto a aquellos sin consumo de tóxicos. El SAD Person muestra diferencias estadísticamente significativas entre los pacientes con y sion consumo (p=0.000). La Escala de Intencionalidad Suicida de Beck no muestra diferencias estadísticamente significativas entre los consumidores y no consumidores. Entre los pacientes de la muestra 5 de ellos acabaron muriendo por suicidio consumado siendo 3 mujeres y 2 hombres. CONCLUSIONES: Casi la mitad de pacientes que acuden a Urgencias tras un intento de suicidio presentan un consumo patológico de tóxicos. El tóxico más frecuente es el alcohol seguido del cannabis. Los pacientes con consumo patológico presenta intentos de suicidio de mayor riesgo

The energy analysis of injection moulding processes is influenced by complex interactions amongst the moulded part, its material, the injection machine, the process parameters and the environmental...

Enterprises must become ‘sensing, smart and sustainable (S3)’ to face global challenges related to local, national and global market dynamics. Therefore, reconceptualisation and redesign in these e...

This work provides a systematized process for the Sensing, Smart and Sustainable Product Development (S 3 -Product) applied to develop Cyber-Physical Production Systems (CPPSs). This reference framework is based on the Integrated Product, Process, and Manufacturing System Development Reference Model (IPPMD). The IPPMD will permit the integration between the different engineering domains that comprise the S 3 -Product (mechanical, electrical/electronic and software engineering). Therefore, the framework proposed provides a set of stages, activities, and tools in order to guide designers in the S 3 -Product realization process. The main objective of this work is to fill the lack of the design roadmaps that permit the realization of this new generation of products. A development of a S 3 -Microfactory as CPPS is presented as case study.

This paper reports the development of a method to improve practical skills. The developed method arises from the observations made to the second-year students of Medicine degree at the National Autonomous University of Mexico (UNAM) in order to improve the learning of practical skills used in the “Introduction to Surgery” course. However, the results obtained can be extrapolated to any profession that requires the usage of manual tools or fine and precise movements of hands. In the case of engineering, the proposed method can be applied to basic courses in electronics, technical drawing, manufacturing engineering, among others. As well as it can be used for specialized training in tasks such as welding, conventional machining, handling of hazardous materials or any other manual activity that requires precision. As a result, a methodology is presented to improve the learning of fine motor skills in a person, this allows developing of his/her professional activities in a fast and accurate way.

"This work has as main objective to expose the unification of the analysis of the functional requirements of mechatronic products, in an integrated reference model of Product, Process and Manufacturing Systems. The scope of the research is defined in the conceptual design stage of mechatronic products, aimed at improving the design process. The Kano, QFD, DSM and CAD methods were used. The main result was the integration of the analysis of the functional requirements in the conceptual design of mechatronic products, using computational tools (CAD/CAM/CAE). The effectiveness of the use of the methodological tools of product design combined with computational tools in the area of mechatronics was demonstrated."

In this article a GHG and energy analysis for the plastic injection process of an ABS medium sized injected part carried out in a hybrid injection molding machine is reported. A power consumption process pattern for an ABS medium-size part is defined as well as the energy usage of components, the energy used for the injection process is calculated for the injection cycle and for the process setup. The reported study includes a hybrid machine analysis working under an electric network that relies mainly on thermoelectric energy generation. The GHG emissions assessment was estimated using the 2015 emission factor applied for Mexico. The results provide new experimental data for ABS plastic injected parts in hybrid injection machines. This paper describes the outcomes of a GHG emissions and energy assessment for an ABS medium-sized injected part carried out in a HIMM at UNAM. The approach followed by the authors in this assessment was aimed at providing information about the energy usage and GHG emissions for the process and the part. The main contribution of this paper is the insight related to energy usage indicators in the process, the energy usage and the GHG emissions within components. The product used as a case study and the results of its GHG emissions and energy assessment are presented.

"Un trastorno frecuente que acompaña a la epidemia actual de obesidad es la apnea del sueño, enfermedad que se caracteriza por la obstrucción parcial o total de la respiración durante el dormir. Actualmente el estudio para su diagnóstico se realiza en clínicas del sueño de instituciones públicas y privadas, sin embargo, la falta de infraestructura y alta demanda provocan largos tiempos de espera, teniendo como consecuencia un deterioro en la salud del paciente. En este trabajo se presenta el proyecto realizado por un equipo multidisciplinario en colaboración con una institución de salud pública con el objetivo de diseñar un servicio-producto innovador que facilite el diagnóstico ambulatorio de dicha enfermedad."

This paper reports on a comparative study realized to contrast between the part code generated by two different CAM systems and one part program generated by the authors. This comparison addresses in particular tool path, but also includes number of lines, cycle time and energy consumption. The comparison is carried out through a case study: a mechanical component was designed so as to produce a number of CNC part programs generated with two different CAM systems; one more program was directly programmed by the authors in the machine tool's controller. Different sample parts were produced using the same machine tool, tooling and process parameters; and measurements of energy consumption and cycle time were gathered. The results show differences between the tool paths generated by each approach and are used by the authors to further define strategies to produce trajectories that could reduce cycle time and energy consumption.

Different types of toolpaths have been extensively studied with regards to different factors such as energy consumption and tool wear. However, toolpaths have been introduced recently, where high speeds and dynamic movements are combined to provide higher performance. The aim of this paper is to compare a spiral toolpath strategy, which has been studied previously with good results in energy consumption, with a high speed dynamic toolpath strategy, which combines helical and dynamic movements, with regards to energy consumption, tool wear and carbon emissions. Several advantages are identified with a high speed dynamic toolpath strategy over the typical spiral toolpath strategy in terms of tool wear, energy consumption and carbon emissions. The results show that the high speed dynamic toolpath is a better alternative for different milling operations such as slotting, pocketing, and face milling.

The number of existing tools, principles and approaches to assess sustainability in products is growing to meet industry and society needs. For those related to design and development in universities, research institutes and companies it is a fundamental issue to recognize features and details of the sustainability assessment tools in order to select the one that best fits their particular needs. This paper describes the outcomes of a product sustainability assessment carried out at Universidad Nacional Autónoma de México, UNAM. The approach followed by the authors in this assessment was aimed at comparing the results provided by a set of software tools and a previous sustainability integrated-criteria tool developed by the research group. The main contribution of this paper is the insight on the software tools used and on the results of the assessment since the design point of view. The results of the assessment included metrics such as: carbon footprint, energy use, end of life potential, toxicity, eco-toxicity, human toxicity, recyclability, and others. In the first part of the paper, an introduction of the criteria and the software based tools for sustainability assessment used by the authors is presented. Then a justification of the tools used and an explanation on how the comparison was achieved are given. The product used as a case study and the results of its sustainability assessment are presented. The case study part is a home appliance subsystem. In the end of the paper conclusions, insights and further work are given.

The data model driven approach argues that computer aided engineering systems should be based on information data models in order to properly support the concurrent design of products. These models are the foundation for database representations of products and factories, and enable information sharing across unlinked software applications that address different stages of the product life cycle. This paper presents a product data model capable of capturing product life cycle information, and in particular its utilization for representing manufacturing information is described. A manufacturing data model that depicts the capabilities of manufacturing cells in terms of their processes and resources is also introduced. The potential benefits of using these data models to support design for manufacture are shown through a case study. The case study includes implementation of the models, their utilization representing a product and three manufacturing facilities, and demonstrates their value in the redesign of a component.

The effectiveness of process models is dependent on the data sharing capability of the CAE system that supports the design process. This assertion is considered in the context of design using Reverse Engineering (RE) techniques, where RE is considered to be a particular type of redesign. Two main categories of information are considered: product-related information, captured in product models, and details of manufacturing capabilities, provided from manufacturing models. This paper reports on conceptual work, which underpins the research and also presents details of a case study, carried out in an industrial context to verify the concepts.

Creation of new products from existing solutions (product re‐design) shortens new product introduction phases and reduces costs. The product re‐engineering process is a new approach to the realisation of substitute components without the benefit of original design process documentation or any other documentation relating to the component. Re‐engineering comprises stages which are potentially applicable to many industries. This research applies an enterprise modelling architecture to modelling the re‐engineering process, producing descriptions of the process from several different descriptive views, namely function, information, resource and organisation. This results in a more complete description of the process, in which the model itself may be used as a reference for the implementation of a re‐design process in a particular company. This research also shows how the information modelling constructs of CIMOSA can be used to meet the particular unique requirements of the process of re‐design.

An innovative product may not be successful when launched to the market arena; this paper explores the use of TRIZ tools at early stages of the user centered design approach (UCD) to develop new products. This paper proposes an application of TRIZ tools through an abstract analysis of the customer’s interactions and the context; this allows a deeper understanding and a comprehensive definition of customer requirements. The authors’ proposal is aimed at identifying innovative commercial successful opportunities. The main contribution of this paper is centered on the integration of the value creation and innovation tools of the UCD approach and TRIZ at early design stages. The first part of the paper describes the link between relevant design methodologies and innovation tools applied by UCD and TRIZ. The next section discusses the integration of UCD and TRIZ. The third section presents applications of this integration. Finally conclusions are presented and further work is described.Copyright © 2013 by ASME

This paper documents the process, the outcomes and the lessons learned from two design courses aimed at incorporating environmental, economic and social concerns during the product development process. These courses are co-taught by professors of the Engineering and the Industrial Design Schools of the Universidad Nacional Autónoma de México (UNAM). Each course lasts one academic semester and includes engineering graduate and undergraduate students from industrial design and engineering. The two courses are “New Product Development” (NPD) and “Design for Sustainability” (DS). The NPD course runs in collaboration with the University of California at Berkeley (UCB) and it has been taught at UNAM since 2008. The course fosters the development of product concepts that address particular user needs related to sustainability issues and enhance user’s experience and innovation. The DS course is aimed at introducing students to the most representative approaches, methodologies and tools related to sustainability. DS takes the NPD process as a background, i.e. takes the NPD product concept produced by students and evaluates its environmental impact, and its technical and economic feasibility. Some issues on entrepreneurship and social responsibility are also covered. For both courses design projects are paramount. Some of the projects carried out by the students during the courses are proposed by students themselves and some others are put forward by companies. The first part of this paper includes some background information on representative sustainability courses reported in the literature. Then the complete process model comprised by the NPD and DS courses is presented. Some details of the actual courses contents and lecture activities are also described. Representative projects developed within the courses, one of which is now a startup company, are presented. Finally, insights and lessons learned are discussed.

A team of faculty members from the Universidad Nacional Autónoma de México (UNAM) has coordinated multidisciplinary courses in collaboration with universities from other countries. The team, who is composed by faculty from the School of Engineering and the School of Architecture, coordinates with pairs of Stanford University, the University of California at Berkeley, and the Technical University of Munich; to teach three particular design courses. All three courses are related to product innovation but they have different emphasis depending on the collaborating partner. The focal points of each of the three courses are: (1) innovation, (2) user centered design and sustainability and (3) transport in megacities of the future. Engineering and industrial design students are involved in the courses. They are organized in teams that include participants from the two collaborating universities. During the courses teams carry out projects working mostly at a distance; they use different means of communication and information sharing and also pay reciprocal visits between the universities involved in the collaboration. This paper describes each of the three courses highlighting their particular characteristics. The outcomes and results of the courses and specific projects are commented. In the end of the paper lessons learned are discussed and final remarks are presented.

This paper describes the final results of a project aiming at addressing climate change by creating a GHG reduction platform for businesses with carbon management needs in global markets. The project was carried out during a New Product Development course in a bi-national program between The University of California at Berkeley (UCB) and the National University of Mexico (Universidad Nacional Autonoma de Mexico, UNAM) in Mexico City. The program features collaboration between the Engineering and Design Schools at UNAM and Engineering and Business Schools at UCB and the College of Architecture CCA. The project, The Carbon Collaborative (TCC) is aimed at consolidating and managing the wide variety of policies and instruments created by governments and environmental organizations to mitigate climate change, and the anthropogenic gas emissions emitted by industry in particular in the US and Mexico. Based on a web platform TCC will provide companies with information on carbon legislation and a centralized location to find transparent and certified methodologies for carbon emission assessment. The differences between the US and Mexican markets lead to advantages for each part. The US market is full of developed consulting enterprises, which is not the case in the Mexican arena, giving to TCC the opportunity of being pioneers to regulate and manage large and small emitters, government environmental agencies and ERP (Enterprise Resource Planning) companies.Copyright © 2010 by ASME

This article presents UNAM’s University-Industry PhD Engineering Program that has been implemented over the last six years to help in the training of young researchers. The program expands along 8 semesters and is strengthened by the Mexican Science and Techology’s (CONACYT’s) funding schemes. Specifically, CONACYT’s new “Funds for Innovation Scheme”, which is intended for corporations that wish to design and develop new products, processes or services. The paper reports on the activities typically carried out by a research student (RS) in each of the 8 semesters and presents the results obtained in the PhD research work titled “Design and Development of a PVC Ampoule Filler-Sealer Machine System”.