Mechatronic Design Approach Research Articles

Mechatronic design of dynamically decoupled manipulators based on the control performance improvement

AbstractThe control of industrial robot manipulators presents a difficult problem for control engineers due to the complexity of their nonlinear dynamics models. Nonlinear controls based on feedback linearization are developed to meet control requirements. Model-based nonlinear control is highly sensitive to parameter errors and leads to problems of robustness for tracking trajectories at high speeds, and there is the additional problem of a heavy computational burden to consider in the design of nonlinear controllers. In this paper, a mechatronic design approach is proposed, which aims to facilitate controller design by redesigning the mechanical structure. The problem is approached in two steps: first, the dynamic decoupling conditions of manipulators are described and discussed, involving redistribution of the moving mass, which leads to the decoupling of motion equations. A classical linear control law is then used to track the desired efficient bang-bang profile trajectory. Then, in the presence of parameter uncertainty and external disturbances, the nonlinear controls with simple structures are adopted to stabilize the decoupled system asymptotically. An analysis of the results from a simulation of this approach demonstrates its effectiveness in controller design. The proposed improvement in control performance is illustrated via two spatial manipulators.

Development and Evaluation of Control System in Mechatronics – A Systematic Survey

The advancement of mechatronic enabling technologies and the mechatronic design approach has resulted in sophisticated mechatronic systems. Automated mechatronic systems are becoming more complicated and more intelligent. Mechanical systems that enable the next generation of manufacturing systems will have whole new features and capabilities as a result of these modifications. Even basic monitoring has grown into self-optimizing performance in these gadgets. With the addition of bio-mechatronics and micro-mechatronics, the application fields of mechatronics have expanded. Bio or microcontroller-based applications are the focus of this publication, which aids researchers in building and testing control systems. Design considerations for mechatronic systems are addressed in this work. In order to implement more complicated control algorithms in an industrial setting, new controller design tools are required. The early evaluation of designs and the support of critical design choices may be made possible via the use of modelling and simulation technologies.

Design and analysis of a novel tendon-driven continuum robotic dolphin

In this paper, a novel continuum robotic dolphin termed ‘ConRoDolI’ is proposed and developed. The biomimetic robot features dual tendon driving continuum mechanisms that are utilized to replicate the twisting and bending motions of the dolphin’s caudal vertebrae and thoracic vertebrae. More importantly, a central pattern generator based kinematics is analyzed to yield stable dolphin-like swimming. In the meantime, the relationship between the backbone shape and both the tendon length as well as position and orientation are explored. Furthermore, multimodal swimming gaits are designed to pave the way for a three-dimensional (3D) swimming decoupling solution, involving forwarding swimming, multiple yaw patterns, and multiple pitch patterns. All of these endow the robotic dolphin with 3D maneuverability. Finally, extensive experiments demonstrate the feasibility of the proposed biomimetic mechatronic design and control approach. The forward swimming speed is 0.44 body lengths per second (BL/s). The steering radius of the robot is about 0.11 BL with an angular velocity of 10°/s and the diving speed is about 0.13 BL/s. The average propulsion efficiency is about 0.6 with the maximum is over 0.8. The obtained results shed light on the improvement of aquatic maneuverability associated with new-concept underwater vehicles.

Mechatronic design and implementation of a bicycle virtual reality system

The aim of this study is to design and implement a virtual reality bicycle system based on a functional-based mechatronic design approach. The development of virtual reality technologies with haptic systems demands a proper integration of the involved disciplines to provide immerse experiences for users. The proposed design approach provides a formal manner to gather the subsystems in the mechatronic device. The developed system is divided in a Virtual Reality System (VRS) and a Physical System (PS) for the design process. The former includes an interactive virtual environment in which an Avatar is animated using a simple kinematic bicycle model. The latter includes an adapted mountain bicycle with haptic feedback mechanisms to interact with the user and to produce the corresponding inputs for the bicycle model. Both systems are integrated by a control behavior system that works under two operation modes, where the user carries out virtual tours and gets feedbacks from a stereoscopic display system, audio cues, and haptic mechanisms. A multibody simulation validates the consistency and the integration of the physical system. In addition, a set of experimental results show the performance of instrumentation elements, control strategies, and feedback mechanisms, to provide the user with an immersive experience in the virtual environment. A brief survey was carried out to assess the opinion of users about the virtual bicycle tours, providing feedback for future improvements. The different designed modules and sub-systems allow modifying and enhancing the VRS without major modifications of the PS, or allow enhancing the physical platform without affecting the functionality of the virtual environment.

Mechatronic design of adjustable serial manipulators with decoupled dynamics taking into account the changing payload

ABSTRACTThis paper deals with the problem of dynamic decoupling of adjustable serial manipulators via a new mechatronic design approach, which is based on the opposite motion of manipulator links and the optimal command design. The goal is to simplify the control by reducing the effects of complicated manipulator dynamics. The opposite motion of links with optimal redistribution of masses allows the cancellation of the coefficients of nonlinear terms in the manipulator’s kinetic and potential energy equations. Then, by using the optimal control design, the dynamic decoupling is achieved. The proposed approach, which is a symbiosis of mechanical and control solutions, improves the known design concepts permitting the dynamic decoupling of serial manipulators whilst taking into account the changing payload. It has two main advantages: at first, the dynamic decoupling of the manipulator is achieved without connection of gears to the links of the manipulator having oscillating motions and at second, the performance of the dynamic decoupling is improved by the changing payload. The suggested design methodology is illustrated by simulations carried out using ADAMS and MATLAB software, which have confirmed the efficiency of the developed approach.

A Mechatronics Approach for Design of Multiview Image Acquisition Setup for Scene Reconstruction with Single Camera

Conventional design approach is being actively replaced by concurrent design approach in the context of interdisciplinary systems. The proposed research work intends to develop a single moving camera based stereo vision system for scene reconstruction with the intrinsic advantage of multi-directional fields of view. The conventional stereo vision setup uses two stationary passive cameras to capture images of a scene from different vantage points. The proposed system imparts varying mechanical degrees of freedom motion for both the object and the camera which aids in acquiring sequence of images which covers all the visible regions of the object of interest. This gives better detail of the scene under consideration as compared to the conventional two images based stereopsis. A mechatronics design approach has been presented which carefully integrates various elements of the system such as the mechanisms, actuators, sensors and the electronic controller. The paper clearly pin points the cues for the design of the mechanical system which are obtained from the requirements of the computer vision system. The relative pose between the camera and the scene is governed by three independent degrees of freedom namely rotation angle for the object, tilt and working distance for the camera. The selection of the aforementioned parameters is decided by the specifications such as field of view, size of the object and sensor and spatial resolution. The proposed design predicts the system to enjoy benefits of reduced cost and improved flexibility in general.

DESIGN OF A VISION GUIDED MECHATRONIC QUADROTOR SYSTEM USING DESIGN FOR CONTROL METHODOLOGY

Designing mechatronic systems is known to be both a very complex and tedious process. This complexity is due to the high number of system components, their multi-physical aspects, the couplings between different engineering domains and the interacting and/or conflicting design objectives. Due to this inherent complexity and the dynamic coupling between subsystems of mechatronic systems, a systematic and multi-objective design approach is needed to replace the traditionally used sequential design methods. The traditional approaches usually lead to functional but non optimal designs solutions. In this paper, and based on an integrated and concurrent design approach called “Design-for-Control” (DFC), a quadrotor UAV equipped with a stereo visual servoing system is used as a case study. After presenting the dynamics and the control model of the Quadrotor UAV and its visual servoing system, the design process has been performed in four iterations and as expected, the control performance of the system has been significantly improved after finishing the final design iteration.

Modeling of a Battery Electric Vehicle (BEV) for Efficient Model-Based Design

For an efficient design process of complex mechatronic systems a continuous and verification-orientated model-based methodology with Model-in-the-Loop (MiL), Software-in-the-Loop (SiL) and Hardware-in-the-Loop (HiL) simulation is suitable. Using such an approach the real-time capable nonlinear multi-body system model of the entire vehicle with the electric power train and the identification of the physical parameters are described. A continuous appliance of the introduced model is a contribution for the frontloading and guarantees a time and cost efficient mechatronic design approach.

Mechatronic Concepts in Design and Control of a Teleoperated Robot

The article proposes a new mechatronic integrated design approach for a robotic system. The proposed method uses modern methods like model based design, rapid control prototyping and hardware in the loop simulations in the development process. Using this method a six DOF teleoperated parallel robot is developed, the results are presented in the paper.

Differential evolution techniques for the structure-control design of a five-bar parallel robot

The present work deals with the use of a constraint-handling differential evolution algorithm to solve a nonlinear dynamic optimization problem (NLDOP) with 51 decision variables. A novel mechatronic design approach is proposed as an NLDOP, where both the structural parameters of a non-redundant parallel robot and the control parameters are simultaneously designed with respect to a performance criterion. Additionally, the dynamic model of the parallel robot is included in the NLDOP as an equality constraint. The obtained solution will be a set of optimal geometric parameters and optimal PID control gains. The optimal geometric parameters adjust the dynamic and the kinematic parameters, optimizing then, the link shapes of the robot. The proposed mechatronic design approach is applied to design simultaneously both the mechanical structure of a five-bar parallel robot and the PID controller.

Hierarchical design models in the mechatronic product development process of synchronous machines

This paper presents an approach for using hierarchical models in the design of mechatronic systems. The utilization and proper combination of solution principles from different domains of mechatronics allow an extended variety and quality of principal solutions, where hierarchical models serve as very important tools for complex design tasks. In order to master the mechatronic design approach and to benefit from it as much as possible, a hierarchical design process is proposed, in which the domain-specific design tasks need not be integrated as a whole on the mechatronic level of the design task. Consequently the models should cover the different views on a system as well as the different degrees of detailing which leads from a hierarchy of models to a hierarchy of design parameters. The specific views of the object represent the relevant phenomena/effects of interest such as geometry, dynamics, stability or material and are used as interfaces for the design engineer during her/his work. Their description by significant quantities is used for analyzing different mechatronic design concepts. The approach is demonstrated by studying the activities during the design process of synchronous machines.

The application of mechatronic design approach in a reconfigurable manufacturing environment

Manufacturing companies are faced with the challenge of unpredictable, high frequency market changes in both local and international markets. Two types of conventional manufacturing system: dedicated manufacturing system (DMS) and flexible manufacturing system (FMS) do not longer meet the requirement of modern manufacturing. So there is a need for greater, more effective responsiveness by manufacturers to change in customer requirements by changing manufacturers' manufacturing capability and capacity. To fulfill this purpose, the concept of reconfigurable manufacturing system (RMS) has been proposed. But according to the literature, there is no suitable methods available yet can be applied directly to reconfigurable manufacturing tools (RMTs) design for RMS. So in this paper, by utilising mechatronics design approach, a full scale reconfigurable machining tool has been designed and analysed.

Badminton playing robot - a multidisciplinary test case in Mechatronics

We present a Mechatronics design approach and related technologies for a badminton playing robot, as a first stage of a multi-year project. The robot is using non-modified shuttles and rackets, which are detected and localized using purely visual information. The robot subsystems are presented: mechanical design, visual detection of the shuttle, shuttle trajectory estimation and interception, actuation, control hardware and software. The paper demonstrates the multidisciplinary nature of the Mechatronics.

A Mechatronic CAN-Based Functional Design and Verification Unified Approach

AbstractA mechatronic system needs an integrated design, implementation and verification unified approach due to multi-disciplinary interactive sub-system components. This paper presents a systematic methodology for a detailed migration from “model in the loop” (MIL), and “software in the loop” (SIL) to “hardware in the loop” (HIL) in order to full fill complicated mechatronic automotive system requirements. Break by wire anti-blocking car system model is implemented and simulated on Matlab™ in real time. For MIL, and SIL a virtual CAN bus channel is designed in order to communicate sensors and actuators signals to/from several electronic control units (ECUs). HIL is implemented to experiment the actual embedded controller performance over a real CAN bus with the real time simulated car model. Both virtual and real experimental results show the efficiency of the proposed approach.

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

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> 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. </para>

Concurrent mechatronic design approach for active control of cavity noise

Active control is a potential solution to many noise and vibration problems for improving the low-frequency performance. Cavity noise reduction as encountered for instance in aircraft cabins and vehicle interiors is a typical example. However, the conventional design of these active solutions may lead to suboptimal products, since the interaction between the vibro-acoustic plant dynamics and control dynamics is usually not considered. A proper way to design such active systems would be considering control and plant parameters concurrently. To cope with this approach, a methodology to derive a fully coupled mechatronic model that deals with both the vibro-acoustic plant dynamics as well as the control parameters is proposed. The inclusion of sensor and actuator models is investigated, since it contributes to the model accuracy as it can confer frequency, phase or amplitude limitations to the control performance. The proposed methodology provides a reduced state-space model derived from a fully coupled vibro-acoustic finite element model. Experimental data on a vibro-acoustic vehicle cabin mock-up are used to validate the model reduction procedure. Regarding noise reduction, optimization results are presented considering both vibro-acoustic plant features, such as thicknesses, and control parameters, such as sensor and actuator placement and control gains. A collocated sensor/actuator pair is considered in a velocity feedback control strategy. The benefits of a concurrent mechatronic design when dealing with active structural–acoustic control solutions are addressed, illustrated and experimentally validated.

Hardware-In-The-Loop Simulation (HILS) Based Design and Evaluation of an Intelligent Gantry Crane System

The use of gantry crane systems for transporting payload is very common in industrial applications. However, moving the payload using the crane is not an easy task especially when strict specifications on the swing angle and on the transfer time need to be satisfied. To overcome this problem, this paper describes development of an intelligent gantry crane system based on the mechatronics design. A lab-scale gantry crane is designed and then its intelligent controllers are developed. Fuzzy logic controllers are adopted, designed and implemented for controlling payload position as well as the swing angle of the gantry crane. The performance of the proposed intelligent gantry crane system is evaluated on a hardware-in-the-loop simulation (HILS) environment. Moreover robustness of the proposed system is also evaluated experimentally in the HILS environment. The result shows that the proposed intelligent gantry crane system designed based on the mechatronics design approach has better performance than the automatic gantry crane system controlled by classical PID controllers. Moreover the result also shows that the intelligent gantry crane system is more robust to parameter variation than the automatic gantry crane system.

The DLR lightweight robot: design and control concepts for robots in human environments

PurposeThe paper seeks to present a new generation of torque‐controlled light‐weight robots (LWR) developed at the Institute of Robotics and Mechatronics of the German Aerospace Center.Design/methodology/approachAn integrated mechatronic design approach for LWR is presented. Owing to the partially unknown properties of the environment, robustness of planning and control with respect to environmental variations is crucial. Robustness is achieved in this context through sensor redundancy and passivity‐based control. In the DLR root concept, joint torque sensing plays a central role.FindingsIn order to act in unstructured environments and interact with humans, the robots have design features and control/software functionalities which distinguish them from classical robots, such as: load‐to‐weight ratio of 1:1, torque sensing in the joints, active vibration damping, sensitive collision detection, compliant control on joint and Cartesian level.Practical implicationsThe DLR robots are excellent research platforms for experimentation of advanced robotics algorithms. Space and medical robotics are further areas for which these robots were designed and hopefully will be applied within the next years. Potential industrial application fields are the fast automatic assembly as well as manufacturing activities done in cooperation with humans (industrial robot assistant). The described functionalities are of course highly relevant also for the potentially huge market of service robotics. The LWR technology was transferred to KUKA Roboter GmbH, which will bring the first arms on the market in the near future.Originality/valueThis paper introduces a new type of LWR with torque sensing in each joint and describes a consistent approach for using these sensors for manipulation in human environments. To the best of one's knowledge, the first systematic experimental evaluation of possible injuries during robot‐human crashes using standardized testing facilities is presented.

Discussion on: “Comparison of Different Multivariable Control Design Methods Applied on Half Car Test Setup”

Parallel structure robots have been receiving growing attentions from both academia and industries in recent years. This is due to their advantages over serial structure robots, such as high stiffness, high motion accuracy and high load-structure ratio. Control of a parallel robot, however, renders a difficult problem to control engineers. To obtain the same degrees of freedom (DOF), a parallel structure is more complex than a serial one, and so is its dynamic model in general. To effectively control a complex mechanical structure for precise and fast performance, an advanced controller embedded with the system's dynamic model is usually desired. In cases of controlling parallel robots, however, the intensive computation due to the complexity of the dynamic model can result in difficulties in the physical implementations of the controllers for high-speed performance. To avoid heavy computation, simplified dynamic models can be obtained by applying simplification techniques, nevertheless, performance accuracy will suffer due to modeling errors. This paper suggests applying a general mechatronics design approach, i.e., the design for control (DFC) approach, to handle this problem. The underlying idea of the DFC approach is that, no matter how complex a system is, as long as its mechanical structure can be judiciously designed such that it can result in a simple dynamic model, a simple control algorithm may be good enough for a satisfactory control performance. As such, complicated controller design can be avoided, on-line computation load can be reduced and better control performance can be achieved. Through out the discussion in the paper, the design and control of a two DOF parallel robot is studied as an illustration example. Resulted control performances of several different mechanical designs derived from the same robot structure topology demonstrate the effectiveness of the DFC approach.

Control performance improvement of a parallel robot via the design for control approach

Parallel structure robots have been receiving growing attentions from both academia and industries in recent years. This is due to their advantages over serial structure robots, such as high stiffness, high motion accuracy and high load-structure ratio. Control of a parallel robot, however, renders a difficult problem to control engineers. To obtain the same degrees of freedom (DOF), a parallel structure is more complex than a serial one, and so is its dynamic model in general. To effectively control a complex mechanical structure for precise and fast performance, an advanced controller embedded with the system's dynamic model is usually desired. In cases of controlling parallel robots, however, the intensive computation due to the complexity of the dynamic model can result in difficulties in the physical implementations of the controllers for high-speed performance. To avoid heavy computation, simplified dynamic models can be obtained by applying simplification techniques, nevertheless, performance accuracy will suffer due to modeling errors. This paper suggests applying a general mechatronics design approach, i.e., the design for control (DFC) approach, to handle this problem. The underlying idea of the DFC approach is that, no matter how complex a system is, as long as its mechanical structure can be judiciously designed such that it can result in a simple dynamic model, a simple control algorithm may be good enough for a satisfactory control performance. As such, complicated controller design can be avoided, on-line computation load can be reduced and better control performance can be achieved. Through out the discussion in the paper, the design and control of a two DOF parallel robot is studied as an illustration example. Resulted control performances of several different mechanical designs derived from the same robot structure topology demonstrate the effectiveness of the DFC approach.