The Experts below are selected from a list of 4845 Experts worldwide ranked by ideXlab platform
Timothy G. Constandinou - One of the best experts on this subject based on the ideXlab platform.
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A compact targeted drug delivery mechanism for a next generation wireless capsule endoscope
Journal of micro-bio robotics, 2016Co-Authors: Stephen P. Woods, Timothy G. ConstandinouAbstract:This paper reports a novel medication release and delivery mechanism as part of a next generation wireless capsule endoscope (WCE) for targeted drug delivery. This subsystem occupies a volume of only 17.9mm3 for the purpose of delivering a 1 ml payload to a target site of interest in the small intestinal tract. An in-depth analysis of the method employed to release and deliver the medication is described and a series of experiments is presented which validates the drug delivery system. The results show that a variable pitch conical Compression Spring manufactured from stainless steel can deliver 0.59 N when it is fully compressed and that this would be sufficient force to deliver the onboard medication.
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A compact targeted drug delivery mechanism for a next generation wireless capsule endoscope
Journal of micro-bio robotics, 2016Co-Authors: Stephen P. Woods, Timothy G. ConstandinouAbstract:This paper reports a novel medication release and delivery mechanism as part of a next generation wireless capsule endoscope (WCE) for targeted drug delivery. This subsystem occupies a volume of only 17.9mm3 for the purpose of delivering a 1 ml payload to a target site of interest in the small intestinal tract. An in-depth analysis of the method employed to release and deliver the medication is described and a series of experiments is presented which validates the drug delivery system. The results show that a variable pitch conical Compression Spring manufactured from stainless steel can deliver 0.59 N when it is fully compressed and that this would be sufficient force to deliver the onboard medication.
Stephen P. Woods - One of the best experts on this subject based on the ideXlab platform.
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A compact targeted drug delivery mechanism for a next generation wireless capsule endoscope
Journal of micro-bio robotics, 2016Co-Authors: Stephen P. Woods, Timothy G. ConstandinouAbstract:This paper reports a novel medication release and delivery mechanism as part of a next generation wireless capsule endoscope (WCE) for targeted drug delivery. This subsystem occupies a volume of only 17.9mm3 for the purpose of delivering a 1 ml payload to a target site of interest in the small intestinal tract. An in-depth analysis of the method employed to release and deliver the medication is described and a series of experiments is presented which validates the drug delivery system. The results show that a variable pitch conical Compression Spring manufactured from stainless steel can deliver 0.59 N when it is fully compressed and that this would be sufficient force to deliver the onboard medication.
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A compact targeted drug delivery mechanism for a next generation wireless capsule endoscope
Journal of micro-bio robotics, 2016Co-Authors: Stephen P. Woods, Timothy G. ConstandinouAbstract:This paper reports a novel medication release and delivery mechanism as part of a next generation wireless capsule endoscope (WCE) for targeted drug delivery. This subsystem occupies a volume of only 17.9mm3 for the purpose of delivering a 1 ml payload to a target site of interest in the small intestinal tract. An in-depth analysis of the method employed to release and deliver the medication is described and a series of experiments is presented which validates the drug delivery system. The results show that a variable pitch conical Compression Spring manufactured from stainless steel can deliver 0.59 N when it is fully compressed and that this would be sufficient force to deliver the onboard medication.
Manuel Paredes - One of the best experts on this subject based on the ideXlab platform.
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A novel design of cubic stiffness for a Nonlinear Energy Sink (NES) based on conical Spring
2016Co-Authors: Donghai Qiu, Sébastien Seguy, Manuel ParedesAbstract:Mitigation of unwanted vibration is an important issue in aeronautics and space area. Since the emergence of innovative absorber Nonlinear Energy Sink (NES), more attentions were paid to this promising technique. This absorber is characterized by a secondary mass highly coupled via a nonlinear stiffness to the main structure that needs to be protected. The mastery of the nonlinearity is a key element for obtaining optimum performance for NES. However, it is difficult to implement cubic stiffness without linear part. In this paper, a novel design NES of cubic stiffnes without linear part is presented. For this, the two conical Springs are specially sized to provide the polynomial components only with linear and cubic term. To counterbalance the linear term, a concept of negative stiffness mech-anism is implemented by two cylindrical Compression Spring. A small sized NES system is developed. To validate the concept, the load-displacement relation test is performed, and simulation under period excitation and transient loading is studied. Future developments will aim experimental validation and application of the prototype.
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Methodology to build an assistance tool dedicated to preliminary design: application to Compression Springs
International Journal on Interactive Design and Manufacturing, 2009Co-Authors: Manuel ParedesAbstract:This paper proposes amethod to develop a design assistance tool dedicated to preliminary design. This tool increases interactivity and enables the design space to be explored. The user-friendly interface proposes to define design parameters with interval values. In addition, an objective has to be selected and the tool offers an optimum design. To take full advantage of all the exploration’s capabilities, it is suggested that all the potential optimization functions be considered as design parameters and that each design parameter be considered as a potential objective function. This method was applied to build a software mock-up dedicated to Compression Spring design. The industrialization process leading to the commercial software is detailed.
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Analytical Behavior Law for a Constant Pitch Conical Compression Spring
Journal of Mechanical Design, 2006Co-Authors: Manuel Paredes, Emmanuel Rodriguez, Marc SartorAbstract:Background. Cylindrical Compression Spring behavior has been described in the literature using an efficient
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Analytical Behavior Law for a Constant Pitch Conical Compression Spring
Journal of Mechanical Design, 2005Co-Authors: Emmanuel Rodriguez, Manuel Paredes, Marc SartorAbstract:Cylindrical Compression Spring behavior has been described in the literature using an efficient analytical model. Conical Compression Spring behavior has a linear phase but can also have a nonlinear phase. The rate of the linear phase can easily be calculated but no analytical model exists to describe the nonlinear phase precisely. This nonlinear phase can only be determined by a discretizing algorithm. The present paper presents analytical continuous expressions of length as a function of load and load as a function of length for a constant pitch conical Compression Spring in the nonlinear phase. Whal's basic cylindrical Compression assumptions are adopted for these new models (Wahl, A. M., 1963, Mechanical Springs, Mc Craw-Hill, New York). The method leading to the analytical expression involves separating free and solid/ ground coils, and integrating elementary deflections along the whole Spring. The inverse process to obtain the Spring load from its length is assimilated to solve a fourth order polynomial. Two analytical models are obtained. One to determine the length versus load curve and the other for the load versus length curve. Validation of the new conical Spring models in comparison with experimental data is performed. The behavior law of a conical Compression Spring can now be analytically determined. This kind of formula is useful for designers who seek to avoid using tedious algorithms. Analytical models can mainly be useful in developing interactive assistance tools for conical Spring design, especially where optimization methods are used.
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Obtaining an optimal Compression Spring design directly from a user specification
Proceedings of the Institution of Mechanical Engineers Part B: Journal of Engineering Manufacture, 2002Co-Authors: Manuel Paredes, Marc Sartor, Cédric MascletAbstract:AbstractCommon mechanical components can be designed manually but this involves problem simplifications. A computer can help to develop a suitable approach for optimizing design. Industrial software for Spring design is comprehensive tools for validation only. To improve design assistance to the designer, this paper presents software which not only is comprehensive but also can serve as a dimensional synthesis tool for Compression Spring design. It exploits an optimization process for use even in the early design steps as specifications are set with interval values. It includes a large set of constraints which can express not only the designer specifications but also the standards and the technical capability limits of Spring manufacturers. This process has been successfully tested by a Spring manufacturer, who has used it to solve real industrial problems for 2 years. One case study is presented.
A.g.hejib - One of the best experts on this subject based on the ideXlab platform.
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Experimental analysis of helical Compression Spring used in two wheeler suspension system
International Journal of Advance Research and Innovative Ideas in Education, 2017Co-Authors: A.g.hejibAbstract:The helical Compression Spring used in two wheelers is belonging to the medium segment of the Indian automotive market. The detailed assessment of the problem of two wheeler suspension Spring is studied. Most of time Springs were failed due to raw material defects, surface imperfection, improper heat treatment, corrosion and decarburization and high weight of suspension. These problems can be solved by applied thick layer of paint as adhesive, proper heat treatment, change in shape and material of helical Compression Spring. In this work, the Spring rate can be increased by change in structure i.e. change in number of active coils of Spring. Theoretical and experimental work is done. Results obtained are compared.
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Analysis of helical Compression Spring used in two wheeler suspension system using Ansys software
International Journal of Advance Research and Innovative Ideas in Education, 2017Co-Authors: A.g.hejibAbstract:The helical Compression Spring used in two wheelers is belonging to the medium segment of the Indian automotive market. The detailed assessment of the problem of two wheeler suspension Spring is studied. Most of time Springs were failed due to raw material defects, surface imperfection, improper heat treatment, corrosion and decarburization and high weight of suspension. These problems can be solved by applied thick layer of paint as adhesive, proper heat treatment, change in shape and material of helical Compression Spring. In this work, the Spring rate can be increased by change in structure i.e. change in number of active coils of Spring. The static stress analysis using finite element method is done.
Mohamed Haddar - One of the best experts on this subject based on the ideXlab platform.
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Interval computation and constraint propagation for the optimal design of a Compression Spring for a linear vehicle suspension system
Mechanism and Machine Theory, 2015Co-Authors: Hassen Trabelsi, Pierre-alain Yvars, Jamel Louati, Mohamed HaddarAbstract:Abstract In this paper an optimization design method based on existing intervals and constraint satisfaction problem “CSP” computer tools is proposed. The method was used in the preliminary design to size a Compression Spring implemented in a linear vehicle suspension system. Compared to conventional design methods, our design method avoids the passing through two stages of sizing (static and dynamic). Using the numeric CSP approach, static and dynamic requirements can be coupled in the same step of sizing. It also avoids the falling on the loop “design–simulate–back to the initial step in case of failure”, as the design parameter values of the Compression Spring generated by the numeric CSP satisfy all imposed requirements, and the simulation results of the system behavior are always successful and respect all posted constraints. This is due to the fact, that in the CSP, all analytical relation types static and/or dynamic defining the product and its behavior are implemented and integrated from the beginning. So the production of a qualifying system can be achieved from the first time without any need for resizing the system. The general idea of the proposed design method consists of expressing the design variables by intervals; integrate all imposed constraints of different types before the simulation step and solve the problem using the CSP. The generated intervals represent the domains of possible values for the design variables of the product. The obtained result which can be a solution or set of solutions, affirms that the suggested method is valid and potentially useful to size dynamic systems easily and effectively.
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CSP approach and interval computation for the coupling between static and dynamic requirements in the preliminary design of a Compression Spring
European Journal of Computational Mechanics, 2013Co-Authors: Hassen Trabelsi, Pierre-alain Yvars, Jamel Louati, Mohamed HaddarAbstract:In this study, a new design approach based on an interval computation method and the constraint satisfaction problem technique (CSP approach) was discussed. It has been applied in the design of a Compression Spring, implemented in the vehicle suspension system. A design process is proposed and compared with what is done in conventional design. IT allows making static and dynamic sizing in one step. In fact, with the CSP, static and dynamic requirements can be coupled in the same step of sizing. In the CSP all requirements imposed can be integrated from the beginning. So it avoids falling on the loop “design-simulate-back to the initial step in case of failure”. In this study, the design parameters values of the Compression Spring generated by the CSP verify all requirements and the resulting simulation of the system behaviour respects all constraints required. The results obtained in this study affirmed that the suggested method is valid and potentially useful to the size dynamic system and can be applied...
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Application of the CSP Approach and the Interval Computation for the Optimal Sizing of a Compression Spring
Lecture Notes in Mechanical Engineering, 2013Co-Authors: Hassen Trabelsi, Pierre-alain Yvars, Jamel Louati, Mohamed HaddarAbstract:In this present study a new design approach based on intervals calculation method and Constraint Satisfaction Problem technique «CSP approach» was discussed. It has been applied in the design of a Compression Spring implemented in vehicle suspension system. Compared to what is done in conventionally design, the design process proposed avoid to go through two stages of sizing (static and dynamic of design steps), since with the CSP, static and dynamic requirements can beings coupled in the same step of sizing. Also it avoids falling on the loop "design-simulate-back to the initial step in case of failure", as in the CSP all requirements imposed can be integrated from the beginning. Therefore the design parameters values of the Compression Spring generated by CSP verify all requirements imposed and the results simulation of the system behavior are always success and respect all constraints required. The general idea of the design process proposed consists to express the design variables by interval, integrate all different types of constraints imposed before simulation step and finally to solve the problem by CSP approach. The intervals generated by CSP represent the domains of possible values for the design variables of the system which satisfy the requirements imposed. The results obtained in this work affirmed that the suggested method is valid.