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Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems

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A special issue of Electronics (ISSN 2079-9292). This special issue belongs to the section "Systems & Control Engineering".

Deadline for manuscript submissions: closed (30 September 2020) | Viewed by 43525

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Special Issue Editors

Dr. Truong Quang Dinh

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WMG, University of Warwick, Coventry CV4 7AL, UK
Interests: lithium-ion batteries; battery thermal management; mechatronics; control theories and applications; modelling; management and control of energy systems; advanced propulsion systems
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Prof. Dr. Adolfo Senatore

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Department of Industrial Engineering, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
Interests: mechatronic systems; frictional modeling and model-based control in automotive transmissions; lubrication in internal combustion engines and journal bearings; effects of nanoparticles as friction reducer additives; vibration measurement methods
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Prof. Dr. James Marco

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Warwick Manufacturing Group, University of Warwick, Coventry CV4 7AL, UK
Interests: battery systems engineering; systems modelling; electric vehicles; fast charging; vehicle-to-grid operations; energy storage
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Dr. Andrew McGordon

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WMG, University of Warwick, Coventry CV4 7AL, UK
Interests: component sizing; batteries; systems modelling; powertrain modelling; supervisory control; powertrain usage cases
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Special Issue Information

Dear Colleagues,

With the rapid development of computer-based technologies, a wide variety of complex mechatronic systems are used in different fields of application, such as robotic systems, manufacturing systems, heavy duty equipment, and transportation systems. Control technology is therefore considered as the key enabler for high-performance mechatronic applications. However, there are always larger numbers of nonlinearities and uncertainties existing in complex mechatronic systems (such as material properties, system parameters, noises, and disturbances). These factors could significantly impact control system performance, leading to the system instability. Hence, it is necessary to develop advanced and accurate models based on effective dynamic analysis and identification methods to have a better understanding of complex mechatronic systems. The developed models could be used to either design advanced control approaches (such as sliding mode control, H-infinity control, model predictive control, and robust adaptive control) or verify the control systems.

The International Conference on Mechatronics Technology (ICMT) is recognised as one of the foremost and world-renowned conference series in the fields of Mechatronics. This year, the 23rd ICMT2019 is held at the University of Salerno, Italy on October 23rd–26th, 2019 and will gather contributions from the broad research community, to present and discuss breakthroughs in the latest developments in Mechatronics and its applications. For further information about the 23rd IMCT 2019, please see: www.icmt2019.org.

This Special Issue aims to publish the highest quality articles, including but not limited to selected papers from the IMCT2019, to contribute to the main theme of ‘Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems’. This Special Issue will therefore introduce the most recent research findings, the progress, and the advancements of mechatronic systems empowered by advanced modelling and control technology, from both theoretical and practical perspectives.

Therefore, the Special Issue welcomes new studies of advanced mechatronic systems in the following fields (but not limited to them):

Advanced modelling technology for complex mechatronic systems with nonlinearities and uncertainties;
Dynamic analysis and innovative identification methods;
Model-based advanced simulation platforms for complex mechatronic systems;
Model-based advanced mechatronic system prediction and predictive control;
Advanced observer design and observer-based control for complex mechatronic systems;
Model-based advanced control of complex mechatronic systems;
Precision control of complex mechatronic systems;
Robust and adaptive control of complex mechatronic systems;
Fault diagnosis and fault-tolerant control in complex mechatronic systems;
Real-time verification of complex mechatronic systems and control.

Dr. Truong Quang Dinh
Prof. Dr. Adolfo Senatore
Prof. Dr. James Marco
Dr. Andrew McGordon
Guest Editors

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Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Electronics is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

complex mechatronic system
nonlinearity and uncertainty
system modelling
system identification
observer
model-based control
observer-based control
prediction and predictive control
precision control
adaptive control
robust control
fault-tolerant control

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Published Papers (12 papers)

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Research

11 pages, 5872 KiB

Open AccessEditor’s ChoiceArticle

A Fast Steering Mirror Using a Compact Magnetic Suspension and Voice Coil Motors for Observation Satellites

by Tadahiko Shinshi, Daisuke Shimizu, Kazuhide Kodeki and Kazuhiko Fukushima

Electronics 2020, 9(12), 1997; https://doi.org/10.3390/electronics9121997 - 25 Nov 2020

Cited by 19 | Viewed by 6138

Abstract

Fast steering mirrors (FSMs) are used to correct images observed by satellites. FSMs need to have large apertures and realize high precision and the positioning of the mirror in the tip-tilt and axial directions needs to be highly precise and highly responsive in order to capture large-scale, high-resolution images. An FSM with a large-diameter mirror supported by a compact magnetic suspension and driven by long-stroke voice coil motors (VCMs) is proposed in this paper. The magnetic suspension and VCM actuators enable the mirror to be highly responsive and to have long-range movement in the tip-tilt and axial directions without friction and wear. The magnetic suspension is a hybrid that has active control in the lateral directions and passive support in the tip-tilt and axial directions. An experimental FSM with an 80 mm diameter dummy mirror was fabricated and tested. The mirror’s driving ranges in the tip-tilt and axial directions were ±20 mrad and ±500 μm, respectively. Furthermore, the servo bandwidths in the tip-tilt and axial directions were more than 1 kHz and 200 Hz, respectively. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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18 pages, 5850 KiB

Open AccessArticle

Development and Experimental Analysis of a Fuzzy Grey Control System on Rapeseed Cleaning Loss

by Xiaoyu Chai, Lizhang Xu, Yang Li, Jie Qiu, Yaoming Li, Liya Lv and Yahui Zhu

Electronics 2020, 9(11), 1764; https://doi.org/10.3390/electronics9111764 - 23 Oct 2020

Cited by 12 | Viewed by 2236

Abstract

One of the most important means of improving the mechanization of rapeseed harvests and increasing farmers’ income is to reduce the cleaning loss of rapeseed. In this study, a fuzzy grey control system was developed using an assembled cleaning loss sensor. Based on experimental data, the relationship between the cleaning loss and the opening of the louver sieve in the cleaning device was obtained. The fuzzy control scheme was established by combining grey prediction and the fuzzy control principle. Secondly, a microcontroller unit (MCU) was used as the controller, and the opening of the louver sieve was automatically regulated by detecting the signal of the cleaning loss. Finally, the performance and robustness of the control system was evaluated in field tests. Different experiments were conducted under different speed conditions to reflect the variable throughput. Results showed that using the grey prediction control system can realize the adjustment of the louver sieve opening in real time. The cleaning loss could be maintained within the ideal setpoint interval, compared with the operation with the control system switched off. These findings indicate that the application of the grey fuzzy control system reduces cleaning loss, and the nonlinear, time-variable and time delay problems in cleaning devices can be solved effectively. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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16 pages, 4139 KiB

Open AccessEditor’s ChoiceArticle

Multi-Sensor Validation Approach of an End-Effector-Based Robot for the Rehabilitation of the Upper and Lower Limb

by Cinzia Amici, Federica Ragni, Manuela Ghidoni, Davide Fausti, Luciano Bissolotti and Monica Tiboni

Electronics 2020, 9(11), 1751; https://doi.org/10.3390/electronics9111751 - 22 Oct 2020

Cited by 23 | Viewed by 2668

Abstract

End-effector-based robots are widely adopted by physiotherapists and caregivers as support in the delivery of the rehabilitation training to the patient. The validation of these devices presents critical aspects, since the system performance must be assessed analyzing the movement performed by the subject limb, i.e., elements outside the device. This paper presents a multi-sensor approach for the validation of an innovative end-effector-based device, comparing different measurement strategies for evaluating the system effectiveness in imposing an expected training. The study was performed monitoring the movement induced by the device on the upper limb of a young male healthy subject during a set of fictitious rehabilitation sessions. The kinematic structure of the device is characterized by a compact differential mechanism with two degrees of freedom. A sequence of repetitions of a planar reaching pattern was analyzed as illustrative training task. A kinematic model of subject and system was developed, and the kinematics of a set of specific landmark points on the subject limb was evaluated. Data obtained from two measurement systems were compared: (1) an optoelectronic system with two cameras and eight skin passive markers, and (2) two triaxial accelerometers. Results were analyzed in MATLAB and R environment, revealing a high repeatability of the limb movement. Although both the measurement systems allow evaluating the acceleration of subject’s arm and forearm, accelerometers should be preferred for punctual analysis, like components optimizations, whereas optical markers provide a general overview of the system, particularly suitable for the functional design process. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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22 pages, 9656 KiB

Open AccessArticle

Output Feedback Control via Linear Extended State Observer for an Uncertain Manipulator with Output Constraints and Input Dead-Zone

by Duc Thien Tran, Hoang Vu Dao, Truong Quang Dinh and Kyoung Kwan Ahn

Electronics 2020, 9(9), 1355; https://doi.org/10.3390/electronics9091355 - 20 Aug 2020

Cited by 24 | Viewed by 3167

Abstract

This paper proposes an output feedback controller with a linear extended state observer (LESO) for an n-degree-of-freedom (n-DOF) manipulator under the presence of external disturbance, an input dead-zone, and time-varying output constraints. First, these issues are derived in mathematical equations accompanying an n-DOF manipulator. The proposed control is designed based on the backstepping technique with the barrier Lyapunov function (BLF) and a LESO. The LESO is used for estimating both the unmeasured states and the lumped uncertainties including the unknown frictions, external disturbances, and input dead-zone, in order to enhance the accuracy of the robotic manipulator. Additionally, the BLF helps to avoid violation of the output constraints. The stability and the output constraint satisfaction of the controlled manipulator are theoretically analyzed and proven by the Lyapunov theorem with a barrier Lyapunov function. Some comparative simulations are carried out on a 3-DOF planar manipulator. The simulation results prove the significant performance improvement of the proposed control over the previous methods. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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14 pages, 4787 KiB

Open AccessArticle

Experimental and Model-Based Study of the Vibrations in the Load Cell Response of Automatic Weight Fillers

by Monica Tiboni, Roberto Bussola, Francesco Aggogeri and Cinzia Amici

Electronics 2020, 9(6), 995; https://doi.org/10.3390/electronics9060995 - 13 Jun 2020

Cited by 8 | Viewed by 3397

Abstract

The paper presents a study of the vibrations in the load cell response of automatic weight fillers for fluids, due to the dynamics of the system. The aim is to characterize vibratory phenomena through both experimental and model-based analysis, in order to identify the main causes and identify compensation strategies. Two test campaigns were conducted, on a test bench and on a sixteen stations machine, with the simultaneous acquisition of acceleration signals and load cell signals. A detailed sensitivity analysis based on experimental data, as many system parameters vary, has been developed. For the system modelling, a one Degree of Freedom (1 DoF) model, with lumped parameters and time-variant mass, including fluidic forces, was considered and numerically implemented. Genetic algorithms were used for the identification problems in the model-based analysis. The model allowed a deeper understanding of the phenomena that occur, showing promising results for the vibration prediction in a compensation process. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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11 pages, 4054 KiB

Open AccessArticle

Development of an Electromagnetic Actuator for the Hot-Embossing Process

by Dongwon Yun and Myeongjin Kim

Electronics 2020, 9(6), 948; https://doi.org/10.3390/electronics9060948 - 8 Jun 2020

Cited by 5 | Viewed by 2473

Abstract

Hot embossing is in the spotlight due to the development of electronic devices, wearable devices, microfluidic channels, and optical devices. The conventional hot-embossing process creates a pattern on polymer film by using a previously patterned stamp that applied heat and pressure. This method has a disadvantage because it depends on the shape of the patterned stamp. For this reason, this method requires a high cost and a lot of time when replacing the stamp for making a new pattern shape or for modifying the error of the pattern. To solve this problem, the impact print-type hot-embossing method was proposed to create arbitrary patterns, and equipment for this method was assembled. In addition, patterning experiments were conducted to imprint several tens of micrometer-sized patterns in real time. For this method, we proposed an electromagnetic actuator for making the hot-embossing print type and for reducing the size of the actuator compared to previous studies. Through the patterning experiment, we determined that the proposed device could engrave fine dot patterns ranging from 60 μm to 120 μm in diameter. We verified the size of the generated pattern by using a confocal microscope, and we found the proposed hot-embossing technology can realize the desired shape in any position by using the proposed technique. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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11 pages, 1053 KiB

Open AccessArticle

A Spline Kernel-Based Approach for Nonlinear System Identification with Dimensionality Reduction

by Wanxin Zhang and Jihong Zhu

Electronics 2020, 9(6), 940; https://doi.org/10.3390/electronics9060940 - 5 Jun 2020

Cited by 3 | Viewed by 2500

Abstract

This paper proposes a novel approach for identification of nonlinear systems. By transforming the data space into a feature space, kernel methods can be used for modeling nonlinear systems. The spline kernel is adopted to produce a Hilbert space. However, a problem exists as the spline kernel-based identification method cannot deal with data with high dimensions well, resulting in huge computational cost and slow estimation speed. Additionally, owing to the large number of parameters to be estimated, the amount of training data required for accurate identification must be large enough to satisfy the persistence of excitation conditions. To solve the problem, a dimensionality reduction strategy is proposed. Transformation of coordinates is made with the tool of differential geometry. The purpose of the transformation is that no intersection of information with relevance to the output will exist between different new states, while the states with no impact on the output are extracted, which are then abandoned when constructing the model. Then, the dimension of the kernel-based model is reduced, and the number of parameters to be estimated is also reduced. Finally, the proposed identification approach was validated by simulations performed on experimental data from wind tunnel tests. The identification result turns out to be accurate and effective with lower dimensions. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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16 pages, 13748 KiB

Open AccessFeature PaperArticle

Tracking Control for an Electro-Hydraulic Rotary Actuator Using Fractional Order Fuzzy PID Controller

by Tri Cuong Do, Duc Thien Tran, Truong Quang Dinh and Kyoung Kwan Ahn

Electronics 2020, 9(6), 926; https://doi.org/10.3390/electronics9060926 - 2 Jun 2020

Cited by 23 | Viewed by 4000

Abstract

This paper presents a strategy for a fractional order fuzzy proportional integral derivative controller (FOFPID) controller for trajectory-tracking control of an electro-hydraulic rotary actuator (EHRA) under variant working requirements. The proposed controller is based on a combination of a fractional order PID (FOPID) controller and a fuzzy logic system. In detail, the FOPID with extension from the integer order to non-integer order of integral and derivative functions helps to improve tracking, robustness and stability of the control system. A fuzzy logic control system is designed to adjust the FOPID parameters according to time-variant working conditions. To evaluate the proposed controller, co-simulations (using AMESim and MATLAB) and real-time experiments have been conducted. The results show the effectiveness of the proposed approach compared to other typical controllers. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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15 pages, 2742 KiB

Open AccessArticle

Basic Reinforcement Learning Techniques to Control the Intensity of a Seeded Free-Electron Laser

by Niky Bruchon, Gianfranco Fenu, Giulio Gaio, Marco Lonza, Finn Henry O’Shea, Felice Andrea Pellegrino and Erica Salvato

Electronics 2020, 9(5), 781; https://doi.org/10.3390/electronics9050781 - 9 May 2020

Cited by 28 | Viewed by 4164

Abstract

Optimal tuning of particle accelerators is a challenging task. Many different approaches have been proposed in the past to solve two main problems—attainment of an optimal working point and performance recovery after machine drifts. The most classical model-free techniques (e.g., Gradient Ascent or Extremum Seeking algorithms) have some intrinsic limitations. To overcome those limitations, Machine Learning tools, in particular Reinforcement Learning (RL), are attracting more and more attention in the particle accelerator community. We investigate the feasibility of RL model-free approaches to align the seed laser, as well as other service lasers, at FERMI, the free-electron laser facility at Elettra Sincrotrone Trieste. We apply two different techniques—the first, based on the episodic Q-learning with linear function approximation, for performance optimization; the second, based on the continuous Natural Policy Gradient REINFORCE algorithm, for performance recovery. Despite the simplicity of these approaches, we report satisfactory preliminary results, that represent the first step toward a new fully automatic procedure for the alignment of the seed laser to the electron beam. Such an alignment is, at present, performed manually. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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17 pages, 3704 KiB

Open AccessFeature PaperArticle

Simulation and Experimental Validation of Novel Trajectory Planning Strategy to Reduce Vibrations and Improve Productivity of Robotic Manipulator

by Andrea Ariano, Valerio Perna, Adolfo Senatore, Roberto Scatigno, Fabio Nicolò, Francesco Fazioli, Giuseppe Avallone, Stefano Pesce and Alberto Gagliano

Electronics 2020, 9(4), 581; https://doi.org/10.3390/electronics9040581 - 30 Mar 2020

Cited by 7 | Viewed by 3844

Abstract

This paper aims at investigating vibrational behaviors of the industrial manipulator Racer 7-1.4, designed and manufactured by COMAU S.p.A., with the target of new trajectory planning strategies to improve productivity rate without any loss of positioning accuracy. Starting from the analysis of a 9DoF multi-body system with lumped parameter, the first natural frequency of the robot was calculated in seven reference positions. Then, static and dynamic simulations were run by applying saturated ramp input and large motions to analyze the vibrational behavior of the manipulator. This research underlines that the optimal way to design the robot move is to set its duration at twice a period of free oscillation according to the first vibrational mode. Due to strong analogy of dynamic response of both 1DoF and 9DoF robot models, the closed-form solution of the 1DoF undamped system—featured by natural frequency equal to the first frequency of the 9DoF system—may be successfully adopted by the real-time trajectory planning process to predict residual vibration at move end-condition. This strategy was confirmed by experimental tests, allowing either residual vibration decrease and execution time reduction as well. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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18 pages, 3713 KiB

Open AccessArticle

Discrete Sliding Mode Speed Control of Induction Motor Using Time-Varying Switching Line

by Grzegorz Tarchała and Teresa Orłowska-Kowalska

Electronics 2020, 9(1), 185; https://doi.org/10.3390/electronics9010185 - 18 Jan 2020

Cited by 10 | Viewed by 3888

Abstract

Sliding mode control (SMC) of electric drives constitutes a very popular control method for nonlinear multivariable and time-varying systems, e.g., induction motor (IM) drives. Nowadays, IM are the most popular electrical machines (EM) applied in many industrial applications as motion control devices, including electrical and hybrid vehicles. Nowadays, the control systems of EM are mostly realized using digital techniques (microprocessors and microcontrollers). Therefore, all control algorithms should be discretized or the whole control system should be designed in the discrete-time domain. This paper deals with a discrete-time sliding mode control (DSMC) for IM drives. The discrete algorithms for sliding mode control of the motor speed and rotor flux are derived in detail and next tested in simulation research. The simulation tests include the discrete nature of the power converter supplying the IM and present excellent performance of the developed control structure. To obtain the rotor speed regulation invariant to external disturbances, like load torque or inertia, especially during the reaching phase of the switching line, the discrete version of a time-varying switching line was introduced. It is shown that the assumed dynamics of the IM flux and speed is achieved and the proposed control algorithm can be realized using commonly available microcontrollers. The paper is illustrated with comprehensive simulation results for 1.5 kW IM drive, which are verified by experimental tests. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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17 pages, 19252 KiB

Open AccessArticle

Modeling and Analysis of an Electromagnetic Fully Variable Valve Train with a Magnetorheological Buffer

by Xiangbin Zhu, Liang Liu, He Guo, Zhaoping Xu, Wenguo Hou and Lu Niu

Electronics 2019, 8(9), 996; https://doi.org/10.3390/electronics8090996 - 5 Sep 2019

Cited by 4 | Viewed by 2888

Abstract

Electromagnetic fully variable valve train (EMVT) technology promises to improve the fuel economy and optimize the engine performance. A novel EMVT equipped with a magnetorheological buffer (EMVT with MR buffer) is proposed to suppress the valve seating impact in this paper. The magnetorheological buffer can adjust the damping characteristics of the whole system in the seating process. Valve precise motion control and better seating performance can be achieved through the coordinated control of electromagnetic linear actuator (EMLA) and MR buffer. For better analysis of system performance, establishing an accurate system dynamic model is the basis of the coordinated control system. A high-order nonlinear precise model integrating dynamics, electromagnetism, and fluid mechanic was established. Then, the Jacobi linearization model is carried out at the equilibrium seating point to build a control-oriented linearized model. The correctness and accuracy of the linearized model is verified. Experiments and simulations show that the valve precise motion can be well controlled to achieve fully variable actuation. And the valve soft landing can be completed under collaborative control. Full article

(This article belongs to the Special Issue Advanced Modelling and Control of Complex Nonlinear Mechatronic Systems)

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