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This paper presents the work to address the problem of student participation in a class. The work is particularly applied to a design-centric mechatronics-related classes, using web, smartphone, and mechatronics-related technology. The specific issues to be targeted on are the irregular attendance and the low participation of students during classes using on-the-spot questions and answers on design-centric subjects to improve and adaptively redirect the orientation of targeted students as well as the whole class. The approach and system have been developed with Android smartphone-based application and Apache Tomcat-based server. This allows data storage and opens up possibility for statistical analysis in the future.

It is known that the PID controller is ill-suited to handle time-delay processes, especially in applications with stringent control objectives to be met. For such purposes, deadtime compensators may be used. But such controllers still face resistance towards actual industrial applications due to their difficulties in implementation and realisation. In this paper, a PID solution involving setpoint weighting is proposed to achieve good setpoint tracking and load regulatory performance. Simulation and experimental results are provided to demonstrate the effectiveness of the proposed approach.

Physics has been an important part of the science curriculum in high schools. Without the appropriate high school physics background, it is difficult for a student subsequently to pursue an electronics engineering program at the university level since a good understanding of many concepts in physics is required to comprehend the material covered in electronics-related courses. Unfortunately, a phenomenon observed in today's high schools is a clear diminution of student interest in physics, leading to dwindling physics class sizes compared to a decade ago. The lack of interest in and passion for physics at the high school level ultimately leads to smaller intakes at the university level for electronics engineering courses and/or lower qualification cutoffs for students entering the programs. This results in a significant reduction in good students graduating from engineering programs. This paper will first share survey results that reveal possible reasons behind the decreasing number of students entering engineering programs. Two concerted efforts launched from the National University of Singapore (NUS) to arrest the declining interest in high schools will then be presented.

A new method for geometrical error compensation of precision motion systems using support vector machines (SVMs) will be developed in this paper. The compensation is carried out with respect to an overall geometrical error model which is constructed from measurements made with respect to each axis of the machine. These error components are modeled using support vector regression method, thus dispensing with the conventional look-up table. The adequacy and clear benefits of the proposed approach are illustrated from an application to a two-axial precision motion platform.

In this paper, a fault detection and accommodation scheme is designed, which is applicable to a large class of nonlinear systems. The nonlinear observer is designed to enable the detection of fault occurrences through comparison of observed states with their signatures. Under such circumstances, when a component fails, the fault accommodation control will be activated to compensate the effects of the fault function.

In this paper, the development of an automated umbilical cord blood (UCB) collection system is presented. The overall control system is comprehensive, comprising of various selected control and instrumentation components, integrated within a configuration of hardware architecture centered around a dSPACE DS1002 Digital Signal Processing (DSP) board. The hardware architecture, software development platform, user interface, and all constituent control components will be elaborated on in the paper.

This paper considers the development of an adaptive online approach for the correction and interpolation of quadrature encoder signals, suitable for application to precision motion control systems. It is based on the use of a two-stage double-layered radial basis function (RBF) neural network. The first RBF stage is used to adaptively correct for the imperfections in the encoder signals such as mean, phase offsets, amplitude deviation and waveform distortion. The second RBF stage serves as the inferencing machine to adaptively map the quadrature encoder signals to higher order sinusoids, thus, enabling intermediate positions to be derived. Experimental and simulation results are provided to verify the effectiveness of the RBF approach.

This paper presents a robust control method for servo mechanical systems, based on a mixed PID/adaptive algorithm. A second-order linear dominant model is considered with an unmodeled part of dynamics that is possibly nonlinear and time-varying. The PID part of the controller is designed to stabilize the dominant model. The adaptive part of the controller is used to compensate for the deviation of the system characteristics from the dominant linear model to achieve performance enhancement. The advantage of the proposed controller is that it can cope with strong nonlinearities in the system while still using the PID control structure which is well known to many control engineers. The proposed control scheme guarantees the boundedness of the system states and parameter estimation.

In this paper, the development of an integrated and open-architecture precision motion control system is presented. The control system is generally applicable, but it is developed with a particular focus on direct drive servo systems based on linear motors. The overall control system is comprehensive, comprising of various selected control and instrumentation components, integrated within a configuration of hardware architecture centred around a dSPACE DS1004 DSP processor board. These components include a precision composite controller (comprising of feedforward and feedback control), a disturbance observer, an adaptive notch filter, and a geometrical error compensator. The hardware architecture, software development platform, user interface, and all constituent control components will be elaborated on in the paper.

This paper presents the development of a dispatching system for a fleet of automated guided vehicles in a flexible manufacturing environment which is based on a hybrid Fuzzy–Taguchi approach. A fuzzy decision-making system emulates the human behavior necessary for multi-objective directed decision making in a dynamically evolving environment. A statistical approach based on the Taguchi method tunes the fuzzy rules to achieve near optimal performance. Simulation results demonstrate the effectiveness of this marriage of computational tools in dealing with the well-known NP-complete scheduling problem.

This paper presents a novel application of Taguchi method to systematically tune the weights of a radial basis function (RBF) network, which is widely used for modelling vaguely defined but smooth nonlinear functions. The main strength of this method is the well-defined and systematic statistical design procedure, which is amenable to practical implementation. To illustrate the effectiveness of the Taguchi-tuned RBF, a test platform is required. This approach is applied to a platform involving high precision motion control. The developed method then is used to tune a composite motion controller incorporating RBF-based adaptive control in a high precision motion environment. Simulation and experimental results reveal the effectiveness of a Taguchi-tuned RBF.

This paper develops a novel genetic algorithm (GA) based methodology for optimal tuning of a reported fuzzy dispatching system for a fleet of automated guided vehicles in a flexible manufacturing environment. The reported dispatching rules are transformed into a continuously adaptive procedure to capitalize the on-line information available from a shop floor at all times. Simulation results obtained show that the GA is very powerful and effective to achieve optimal fuzzy dispatching rules for higher shop floor productivity and operational efficiency.

In this paper, we propose a flexible dispatching system for unit load automated guided vehicles in a flexible manufacturing environment, using a self-adapting fuzzy logic-driven approach. Unlike conventional heuristical approaches, we are able to satisfy a multi-criterion formulation of factors affecting the dispatch decision. The system also has a self-adaptation feature in that respective influence of the elementary rules may be continuously adapted to suit the manufacturing environment. Simulation results are provided to compare the effectiveness of the approach against current methodologies.

The human placenta and umbilical cord blood (UCB) provide a rich source of highly-proliferative haematopoietic stem cells (HSCs) for many clinical uses with advantages over traditional sources like the bone marrow and periphery blood. However, the current constraint with this source of HSCs is the inadequate number of HSCs cells which can be harvested in a single collection using current approaches which render a large number of collections unusable on their own, even for paediatric patients. The large reservoir of useful HSCs within the placenta has to be discarded upon the delivery of the placenta out of the maternal body. The user-centric approach is adopted in this project to tackle the social and technical issues related to the harvesting of HSCs. On the social portion, an in-depth ethnographic study is conducted over 3 months in the delivery wards to understand the concerns of the users. The results will be useful to promote the collection of HSCs in the cord blood banks. In addition, a novel device (i.e. amenable to be readily deployable in the delivery wards) that could improve the harvest of stem cells will also be developed, taking into consideration the needs of the various stakeholders. Initial proof-of-concept results have provided good motivation to proceed with the full scale development of the proposed device.

Electric Vehicles (EVs) have become a popular alternative to Internal Combustion Engine Vehicles (ICEVs) due to its ability to be replenished by renewable sources of energy. Despite its advantages, EVs still possess some major disadvantages, which have reduced the take up rate of EVs by consumers. This project is therefore proposed to provide a user-centric solution to evaluate and to encourage the use of EVs In particular, the project aims to establish a remote telemetry and diagnostics System for EVs. In this project, a database system has been developed, which is used with a compatible data acquisition system. The developed database system is able to store the relevant and useful information for the EV users, and they may be used by engineers and researches to conduct data mining for research and development purposes. In addition, smart phone application has been developed for the iPhone to provide EV users with real-time critical information that will alleviate the anxieties mentioned above. Furthermore, a tablet application has also been developed to give technicians access to vital information regarding their clients' EVs, and also to past information, which is useful when diagnosing a problem.

In this paper, the development of an automated umbilical cord blood (UCB) collection instrument, comprising of mechanical, electronics and control components, is provided in detail. UCB from the placenta provides a rich source of highly proliferative cells for many clinical uses as it contains rich Hematopoietic Stem Cells (HSCs) which yield many benefits over traditional sources such as the bone marrow and periphery blood. Current collection of UCB uses a syringe to extract blood from placenta, which is highly limited in volume and cell numbers. This paper will present the development of an automated UCB collection instrument to yield improved performance which comprised four subsystems. First, a placenta handling system is designed to produce air pressure which can realize the emulation of the uterus compression on the placenta. Second, an auto-medium injector system is presented to enable perfusion automatically. Third, a time window widening system is developed which generates vibrations during the perfusion phase and helps the exposed end of the cord cool down to a low temperature. Finally, a control platform is used to integrate all systems working together, hosting the control algorithms which operate the instrument automatically.

The human placenta and umbilical cord blood (UCB) provide a rich source of highly-proliferative haematopoietic stem cells (HSCs) for many clinical uses with advantages over traditional sources like the bone marrow and periphery blood. However, the current constraint with this source of HSCs is the inadequate number of HSCs cells which can be harvested in a single collection using current approaches which render a large number of collections unusable on their own, even for paediatric patients. The large reservoir of useful HSCs within the placenta has to be discarded upon the delivery of the placenta out of the maternal body. A novel design, involving mechanical, electronics and control components, seeks to create an artificial uterus force to harvest the HSCs. This paper will present the development of this automated device to enable more effective harvesting of HSCs from placentas, upon the discharge of placentas after deliveries. Preliminary results, in terms of mononucleated cells (MNCs) count and CD34+ cells count, will be furnished to verify the effectiveness of the developed system, over the other current approaches.

Hematopoietic stem cells (HSCs) from the human placenta and umbilical cord blood (UCB) provide a rich source of highly proliferative cells for many clinical uses with advantages over traditional sources like the bone marrow and periphery blood. However, the key current constraint with this source of HSCs is the inadequate number of HSCs cells that can be harvested in a single collection using current approaches, which render a large number of collections unusable on their own, even for pediatric patients. This paper will present the development of a device to enable more efficient harvesting of HSCs from placentas, which can be used ex utero, upon the discharge of placentas after deliveries. The device can be used to facilitate a two-fraction collection process. Results, in terms of mononucleated cells (MNCs) count, CD34+ cells count, as well as flow cytometry, will be furnished to verify the effectiveness of the developed system.

Introduction Intracytoplasmic sperm injection (ICSI) and the subsequent cell electro-activation process is a relatively new enhanced procedure to address male factor infertility. The current method involves the engagement of experienced embryologists for such a purpose. More advanced methodologies, which use high precision instrumentation tools, will speed up the whole procedure. Methods In this paper, the development of a computer-controlled system for ICSI and the subsequent cell electro-activation process is presented. The system is integrated to a microinjection workstation and piezo-actuator to perform the ICSI procedure, with vision capability to automatically position the components precisely. A micro-pump assembly is utilized for automatic medium refreshment and a heater plate assembly provides temperature control during the cell electro-activation process. The overall system is comprehensive, comprising modular functional components integrated within a hardware architecture. Results Experimental results on mice oocytes verified the effectiveness of the developed system over the current method. Conclusions Further improvements on the instrumentation tools will improve the robustness and overall performance of the developed system. Copyright © 2009 John Wiley & Sons, Ltd.

A numerical study has been carried out on the validity of the low Mach number limit of the Navier-Stokes equations for unsteady chemically reacting flows. This limit is very useful since pressure waves are eliminated from the equations, and the analysis of many problems can be considerably simplified. The results from this research have shown that the model can lead to inconsistent results when rapid chemistry and density changes occur in a flow. The inconsistency is fundamental to the low Mach number model, and results in large dynamic pressure changes due to fluid particle acceleration. The high fluid particle acceleration follows directly from the assumption of constant thermodynamic pressure and rapid chemical reactions. In most applications the pressure changes quickly die out, and the assumptions of the model become valid. Besides the lack of physical validity the problem of large dynamic pressures leads to serious numerical problems due to lack of resolution and interaction with boundary conditions. The results of this study also apply to the Stephan model, and they give insight into many of the previous problems that occurred for low Mach number and incompressible flows. A method of correction for some of the numerical difficulties has been given in the paper, however the question of physical validity appears to be fundamental. Another topic contained in the paper is a comparison between the full Navier-Stokes equations and the low Mach number model for an one-dimensional, unsteady flame propagation problem. The results of this study show that the full Navier-Stokes equations can be competitive in terms of efficiency and accuracy for problems involving rapid chemistry.

In the past, following the birth of a baby, the umbilical cord is usually discarded along with the placenta. It is now known that blood retrieved from the umbilical cord, commonly known as umbilical cord blood (UCB), is an increasingly important rich source of stem cells (Cairo and Wagner, 1997). These cells obtained from UCB can produce all other blood cells, including blood-clotting platelets, and red and white blood cells. In a way, UCB is similar in primary functions to donated bone marrow. The cells that are harvested from UCB or bone marrow can be used for the treatment of over 45 malignant and non-malignant diseases, including certain cancers such as leukemia, and immune and genetic disorders. UCB provides a readily available source of stem cells for transplantation in many situations where bone marrow is now used. More critically, there are many advantages to use UCB instead of other sources of stem cells such as bone marrow and peripheral blood

This paper presents a combined control scheme, comprising of the well-known PID controller augmented with a radial basis function neural network (RBFNN) for the control of servo mechanical systems. A second-order linear dominant model is considered with an unmodeled part of dynamics that is possibly nonlinear and time-varying. The PID part of the controller is designed to stabilize the dominant model. The RBFNN is used to compensate for the deviation of the system characteristics from the dominant linear model to achieve performance enhancement. The advantage of this combined control scheme is that it can cope with strong nonlinearities in the system while still using the PID control structure which is well-known to many control engineers.

In this paper, the application of a dual relay feedback approach towards modeling of frictional effects in servo-mechanisms is addressed. The friction model consists of Coulomb and viscous friction components, both of which can be automatically extracted from suitably designed relay experiments. At the same time, the dynamical model of the servo-mechanical system call be obtained from the experiments. With the models, a PID feedback motion controller and a feedforward friction compensator can be automatically tuned.

This paper presents the development of a mechatronic experiment on the remote vibration signature analysis via the Internet. It will highlight the hardware and software requirements for the implementation of the remote experiment.

In this paper, the development of a motion control system for ultra-precision semiconductor and electronic components manufacturing is presented. The control system is generally applicable, but it is developed with a particular focus on direct drive servo systems based on linear motors. The overall control system is comprehensive, comprising of various selected control and instrumentation components, integrated within a configuration of hardware architecture centred around a dSPACE DS1004 DSP processor board. These components include a precision composite controller (comprising of feedforward and feedback control), a disturbance observer, an adaptive notch filter, and a geometrical error compensator. The hardware architecture, software development platform, user interface, and all constituent control components will be elaborated on in the paper.

In this paper, an application for monitoring and control of machine health using vibration sensing is developed. This vibration analyzer is able to continuously monitor and compare the actual vibration pattern against a vibration signature, based on a fuzzy fusion technique. More importantly, this intelligent knowledge-based real-time analyzer is able to detect excessive vibration conditions much sooner than a resulting fault could be detected by an operator. Subsequently, appropriate actions can be taken, say to provide a warning or automatic corrective action. This approach may be implemented independently of the control system and as such can be applied to existing equipment without modification of the normal mode of operation. Simulation and experimental results are provided to illustrate the advantages of the approach taken in this application.

The stream function equation is solved for steady two-dimensional (and axisymmetric) rotational flows. Both finite differences and finite volumes discretization techniques are studied, using generalized body fitted coordinates and unstructured staggered grids, respectively. For inviscid transonic flows, a new artificial viscosity scheme which does not produce any artificial vorticity is introduced, for the stability of the mixed flow calculations and for capturing shocks. The solution of Euler equations, in primitive variables, are also considered. The effects of the artificial viscosity and numerical boundary conditions on the total enthalpy and the vorticity distributions are demonstrated.

Precision control is the core of many applications in the industry, particularly robotics and drive control. To achieve it, precise measurement of the signals generated by incremental encoder sensors is essential. High precision and resolution motion control relies critically on the precision and resolution achievable from the encoders. In this paper, a dynamic neural network-based approach for the correction and interpolation of quadrature encoder signals is developed. In this work, the radial basis functions (RBF) neural network is employed to carry out concurrently the correction and interpolation of encoder signals in realtime. The effectiveness of the proposed approach is verified in the simulation results provided.