System-Based and Concurrent Design of a Smart Mechatronic System Using the Concept of Mechatronic Design Quotient (MDQ)

A mechatronic system needs an integrated, concurrent, and system-based design approach due to the existence of interactions among its subsystems, and also the existence of interactions between the criteria involved in a realistic evaluation of a mechatronic product. This paper presents a systematic methodology for a detailed mechatronic design based on a mechatronic design quotient (MDQ). MDQ is a multicriteria index, reflecting a system-based evaluation of a mechatronic design, which is calculated using soft computing techniques, thereby accommodating interactions between criteria and human experience. A niching genetic algorithm is utilized to explore the huge search space raised due to concurrent and integrated design approach, with the aim to find the elite representatives of different possible configurations. To demonstrate the method, it is applied to an industrial fish cutting machine called the Iron Butcher-an electromechanical system that falls into the class of mixed or multidomain systems.     

Mechatronic Design Quotient as the Basis of a New Multicriteria Mechatronic Design Methodology

A concurrent, integrated, and multicriteria methodology is presented for the conceptual design of mechatronic systems. It uses an evaluation model called mechatronic design quotient (MDQ) to facilitate decision-making in the design process. A nonlinear fuzzy integral is used for the aggregation of criteria in MDQ, thereby accommodating possible correlations among them. The performance of the developed methodology is validated by applying it to an industrial fish cutting machine called Iron Butcher-an electromechanical system that falls into the class of mixed or multidomain systems     

Design of Mechatronic Systems With Configuration-Dependent Dynamics: Simulation and Optimization

This paper considers the simulation and optimization of mechatronic systems with configuration-dependent dynamics. A modeling methodology, able to capture the varying dynamics and the embedded control system actions, using affine reduced models and cosimulation, is proposed. In this way, mechatronic systems with configuration-dependent dynamics can be evaluated during the design phase. This methodology is applied to a pick-and-place assembly robot and an experimental validation is carried out. The mechatronic design approach, which takes into consideration structural and control parameters, is considered. Using time-domain metrics, two control strategies are derived: a linear time-invariant proportional--integral--derivative (PID) controller and a linear parameter-varying PID controller. Finally, design tradeoffs are evaluated in a truly mechatronic approach.      

Holistic system modeling in mechatronics

This paper outlines an alternative modeling scheme for mechatronic systems, as a basis for their concurrent design. The approach divides a mechatronic system into three generic subsystems, namely generalized executive, sensory and control, and links them together utilizing a combination of bond graphs and block diagrams. It considers the underlying principles of a multidisciplinary system, and studies the flow of energy and information throughout its different constituents. The first and second laws of thermodynamics are reformulated for mechatronic systems, and as a result three holistic design criteria, namely energy,entropy and agility, are defined. These criteria are formulated using the bond graph representation of a mechatronic system. As a case study, the three criteria are employed separately for concurrent design of a five degree-of-freedom industrial robot manipulator.     

Integrated structure and control design for mechatronic systems with configuration-dependent dynamics

This paper considers the optimal design of mechatronic systems with configuration-dependent dynamics. An optimal mechatronic design requires that, among the structural and control parameters, an optimal choice has to be made with respect to design specifications in the different domains. Two main challenges are treated in this paper: the non-convex nature of the optimization problem and the difficulty in modeling serial machines with flexible components and their embedded controllers. The optimization problem is treated using the direct design strategy which considers simultaneously structural and control parameters as variables and adopts non-convex optimization algorithms. Linear time-invariant and gain-scheduling PID controllers are addressed. This methodology is exploited for the multi-objective optimization of a pick-and-place assembly robot with a gripper carried by a variable-length flexible beam. The resulting design tradeoffs between system accuracy and control efforts demonstrate the advantage of an integrated design approach for mechatronic systems with configuration-dependent dynamics.     

Design for control-a concurrent engineering approach formechatronic systems design

The well-accepted basis for developing a mechatronic system is a synergetic concurrent design process that integrates different engineering disciplines. In this paper, a general model is derived to mathematically describe the concurrent design of a mechatronic system. Based on this model, a concurrent engineering approach, called design for control (DFC), is formally presented for mechatronic systems design. Compared to other mechatronic design methodologies, DFC emphasizes obtaining a simple dynamic model of the mechanical structure by a judicious structure design and a careful selection of mechanical parameters. Once the simple dynamic model is available, in spite of the complexity of the mechanical structure, the controller design can be facilitated and better control performance can be achieved. Four design scenarios in application of DFC are addressed. A case study is implemented to demonstrate the effectiveness of DFC through the design and control of a programmable four-bar linkage     

Knowledge interaction with genetic programming in mechatronic systems design using bond graphs

This paper describes a unified network synthesis approach for the conceptual stage of mechatronic systems design using bond graphs. It facilitates knowledge interaction with evolutionary computation significantly by encoding the structure of a bond graph in a genetic programming tree representation. On the one hand, since bond graphs provide a succinct set of basic design primitives for mechatronic systems modeling, it is possible to extract useful modular design knowledge discovered during the evolutionary process for design creativity and reusability. On the other hand, design knowledge gained from experience can be incorporated into the evolutionary process to improve the topologically open-ended search capability of genetic programming for enhanced search efficiency and design feasibility. This integrated knowledge-based design approach is demonstrated in a quarter-car suspension control system synthesis and a MEMS bandpass filter design application.     

Optimal construction and control of flexible manipulators: a case study based on LQR output feedback

A mechatronic approach is studied here to design the mechanical system and controller concurrently for a robotic flexible manipulator. There is no coupling effects among these components which exit in traditional sequential design and this concurrent development leads to the global optimal performance. A linear quadratic regulator with output feedback is used to compare the results obtained from the traditional approach and this mechatronic approach. Using the mechatronic approach, optimal beam shapes as well as the associated optimal controllers for different feedback structures and for different objective functions can be achieved. Numerical results have indicated substantial improvements on performance.     

Interface model enabling decomposition method for architecture definition of mechatronic systems

Solving a complex problem often requires a way to break it down into smaller, interconnected and manageable sub-problems, and then to join them together. The concept of breaking down a problem into smaller pieces is generally referred to as decomposition. The design of mechatronic systems is an example of such complex problems, as it is based on the integration of several disciplines, such as mechanical, electrical and software engineering. Decomposition is thus a common technique to help designers to obtain solutions for the design of mechatronic systems during the systems engineering process. However, an effective decomposition method which can fully solve the design problems of mechatronic systems has not yet been proposed in systems engineering.The goal of the paper is to formalise this decomposition method based on an interface model. This method is applicable to the architecture definition in the context of the design of mechatronic systems during their conceptual design phase. The proposed decomposition method provides designers with high-level guidance to help them to achieve the appropriate hierarchies and granularities for the architecture of mechatronic systems. The proposed decomposition method is applied and demonstrated using the systems engineering practices of a 3D measurement system.     

A mechatronic approach to microsystem design

This paper discusses the implementation of a concurrent-engineering view of microsystem design. The proposed concurrent-engineering or mechatronic approach to the design of hybrid microsystems is illustrated by three case studies. First, the design of an advanced computer writing tool is discussed. The design of this consumer product requires a mechatronic approach at different functional levels and at different levels of miniaturization. Another illustration of this approach is the design of an implantable drug delivery device. A device for solid drug delivery, as well as a device for liquid drug delivery, are presented. It is demonstrated that miniaturization can be obtained by a combination of functions in a single component. The multiplication of functions in a single component automatically leads to a concurrent-engineering approach far the design. Finally, the micromanufacturing of silicon parts by electrodischarge machining is described. It is demonstrated that electrodischarge machining of silicon is not only feasible, but forms an interesting and complementary technology to traditional silicon micromachining. Therefore, this powerful manufacturing technique opens the way for concurrent engineering of real three-dimensional micromechanical sensors and actuators with integrated processing electronics on the same wafer     

An integrated mechatronic approach for the systematic design of force fields and programming of microactuator arrays for micropart manipulation

Micromanipulation is a hot topic in the rapidly emerging area of micromechatronics and particularly in the manufacturing and assembling of micromechatronic products. This paper introduces an integrated mechatronic approach for the systematic design and operation of flexible, sensorless, automated micromanipulation for a variety of microparts on microactuation arrays. This approach is a mechatronic synthesis of methods from different engineering areas such as solid modeling, electronics design, software for control and programming of mechanical actuation. It involves designing of programmable force fields for manipulation of convex or non-convex polygonal microparts on an array, hardware programmable circuitry for the activation of the array and a software algorithmic procedure for the programming. A detailed analysis is given, as well as several simulated experiments performed using the introduced approach on a cilia microactuator array for a variety of polygonal asymmetric and non-convex microparts and the results are presented and discussed. Finally, the advantages and limitations of this approach are analyzed and points for further research are raised.     

Teaching control system design through mechatronics: academic and industrial perspectives

The present approach to teaching control system design as a stand-alone course offered late in the undergraduate curriculum, with little discussion of hardware, implementation, or integration through design, is ineffective in preparing students for engineering practice. Control systems must be integrated into the design from the beginning and not be simply after-thought add-ons. Based on the authors' extensive experience teaching mechatronics to university students and professional engineers, an integrated mechatronic approach to teaching controls is proposed. This approach will seriously address the deficiencies in the present-day skills of working professionals, as observed by the authors in teaching professional engineering workshops. These deficiencies are a direct result of how we presently teach controls and related topics.     

Nonlinear control of mechatronic systems with permanent-magnet DC motors

The current trends in development and deployment of advanced electromechanical systems have facilitated the unified activities in the analysis and design of state-of-the-art motion devices, electric motors, power electronics, and digital controllers. This paper attacks the motion control problem (stabilization, tracking, and disturbance attenuation) for mechatronic systems which include permanent-magnet DC motors, power circuity, and motion controllers. By using an explicit representation of nonlinear dynamics of motors and switching converters, we approach and solve analysis and control problems to ensure a spectrum of performance objectives imposed on advanced mechatronic systems. The maximum allowable magnitude of the applied armature voltage is rated, the currents are limited, and there exist the lower and upper limits of the duty ratio of converters. To approach design tradeoffs and analyze performance (accuracy, settling time, overshoot, stability margins, and other quantities), the imposed constraints, model nonlinearities, and parameter variations are thoroughly studied in this paper. Our goal is to attain the specified characteristics and avoid deficiencies associated with linear formulation. To solve these problems, an innovative controller is synthesized to ensure performance improvements, robust tracking, and disturbance rejection. One cannot neglect constraints, and a bounded control law is designed to improve performance and guarantee robust stability. The offered approach uses a complete nonlinear mechatronic system dynamics with parameter variations, and this avenue allows one to avoid the conservative results associated with linear concept when mechatronic system dynamics is mapped by a linear constant-coefficient differential equation. To illustrate the reported framework and to validate the controller, analytical and experimental results are presented and discussed. In particular, comprehensive analysis and design with experimental verification are performed for an electric drive. A nonlinear bounded controller is designed, implemented, and experimentally tested.     

A model-based design methodology for the development of mechatronic systems

The development of mechatronic systems involves the use of multiple disciplines, from mechanical engineering to electronics engineering and computer science.Traditionally, every discipline was developed independently and then integrated to generate the final system. However, high-quality designs cannot be achieved without simultaneously considering all the engineering disciplines. This integrated approach carries an intrinsic complexity into system design process and numerous researches are on-going in order to find out optimal methods. This article illustrates a methodology based on Model-Based System Engineering to support the integrated development of complex mechatronic devices. The main contribution is the introduction of a design methodology based on the W model and the identification of SysML as the tool to support the whole process.This method will also address the problem of “devices interchangeability”, that means the possibility to develop the functionality of a system with different operation principles, at a very early stage of the development process (i.e. during the conceptual development). To achieve this goal, the methodology treats the problem of linking the conceptual with executable models to enable the validation by simulation.Main advantages of this methodology are in providing, to the mechatronic systems designers, a fixed schedule which does not limit their intuition and reduces complexity through a hierarchical approach. The process has been tested through the rationalization of the choices that have brought to the current solution of the filling system of an automatic filling machine for liquid foodstuff.     

A hybrid systems approach toward modeling and dynamical simulation of dextrous manipulation

This paper presents an approach toward comprehensive discrete-continuous modeling and accurate dynamical simulation of dextrous manipulation. The resulting hybrid-state model integrates time-driven mechanical features of manipulation systems as well as their discrete-event aspects resulting from varying contact situations. It can easily be embedded into sophisticated simulation environments. A MATLAB implementation serves us as a tool for mechatronic control design for grasping systems. Results from dynamical simulations of a four-fingered hand grasping and manipulating an object demonstrate the efficiency and high accuracy of our approach.     

Vision-in-the-loop for control in manufacturing

Machine vision is an invaluable component of automated manufacturing in situations where a high degree of randomness in the product, or the process, prevents the construction of a suitably structured environment for traditional automation or robotics. Case studies are presented of four mechatronic systems developed, or being researched, for quite different processes in the textile industry: garment assembly, lace cutting (scalloping), lace inspection and inkjet printing. They illustrate the potential for vision-in-the-loop in manufacturing. Although divergent in their purposes, the systems share a common theme: they each use line-scan machine vision, ‘incremental’ image processing rather than frame-based techniques and an integrated mechatronic design approach.     

Telescopes as mechatronic systems

The system design of telescopes is usually dominated by the aspects of the optics and receiving instruments. The telescope structure, mechanism, and control are "only" aids to position these elements toward the celestial target, but their quality has a big impact on the final performance. This paper describes an integrated design approach to these "mechatronic" telescope subsystems.