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18 pages, 2329 KiB

Open AccessArticle

Re-Optimized Design for the ADR-Based Dual-Loop Controller of 100 m Class Aperture Radio Telescope

by Ning Li, Qian Xu, Na Wang and Zhiyong Liu

Machines 2024, 12(7), 448; https://doi.org/10.3390/machines12070448 - 28 Jun 2024

Viewed by 280

Abstract

Pointing accuracy is a crucial performance index for a fully steerable large-aperture radio telescope and is subject to external and internal disturbances. Improvement of the antenna’s servo control performance is meaningful for pointing, especially for blind pointing of the antenna. This paper firstly [...] Read more.

Pointing accuracy is a crucial performance index for a fully steerable large-aperture radio telescope and is subject to external and internal disturbances. Improvement of the antenna’s servo control performance is meaningful for pointing, especially for blind pointing of the antenna. This paper firstly establishes a multi-motor-driving four-degrees-of-freedom (DOF) model of an antenna servo system, then optimizes the original design consisting of the active disturbance rejection (ADR)-based velocity controller and lead–lag-based position controller, making the velocity controller a novel linear ADR-based controller coupled with a disturbance-velocity compensation (DLADRC) and the position controller the simplest proportional (P) controller. Simulation results based on a 100 m class radio telescope servo model indicate that the new control system’s velocity-loop response is smoother, the position-loop peak disturbance response is reduced by 17.8%, the position-loop dynamic performance with the short settling time and slight overshoot remains the same as the former PD-LADRC system, and the RMS pointing/tracking error is 2.16 arcsec under a mean wind of 3 m/s, less than the design specification of 2.5 arcsec RMS required. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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28 pages, 12978 KiB

Open AccessArticle

A Novel Double Closed Loop Control of Temperature and Rotational Speed for Integrated Multi-Parameter Hydro-Viscous Speed Control System (HSCS)

by Kai Zhao, Yuan Wang, Shoukun Wang, Feiyue Gao, Xiang Feng, Hu Shen, Lin Zhang, Liang Wang, Bin Yu and Kaixian Ba

Machines 2024, 12(6), 394; https://doi.org/10.3390/machines12060394 - 10 Jun 2024

Viewed by 451

Abstract

Hydro-viscous clutch has already become an inevitable choice for special vehicle transmission in the present and future. As a nonlinear system with a large hysteresis loop, its speed control performance is affected by input rotational speed, lubricating oil temperature, lubrication pressure, and other [...] Read more.

Hydro-viscous clutch has already become an inevitable choice for special vehicle transmission in the present and future. As a nonlinear system with a large hysteresis loop, its speed control performance is affected by input rotational speed, lubricating oil temperature, lubrication pressure, and other factors. The traditional control method cannot adjust the temperature and rotational speed, which will lead to problems of narrow speed range, poor rotational speed stability, and large dynamic load impact. In order to solve the above problems, this paper studies the control method of an integrated multi-parameter hydro-viscous speed control system (HSCS) in a controlled environment. Through the mechanism analysis of the law of HSCS, the influence law of speed and temperature during the system operation is found. The temperature closed loop based on model predictive control (MPC) is introduced to control the rotational speed, and then the traditional PID control results are compensated according to the speed closed loop. Next, a novel double closed loop control method of temperature and rotational speed for HSCS is formed. Finally, the simulating verification is carried out. Compared with the traditional control method, the design method in this paper can adjust the control parameters according to the temperature of the lubricating oil and the input rotational speed and effectively expand the domain of HSCS and the speed control stability. The effective transmission ratio is extended to 0.2~0.8, and the hydro-viscous torque and speed fluctuation under the engine rotational speed fluctuation are reduced by more than 30%. The novel control method of HSCS designed in this paper can effectively improve the influence of input rotational speed and lubricating oil temperature on the speed control performance of HSCS and can be widely used in nonlinear HSCS such as hydro-viscous clutch. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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17 pages, 7493 KiB

Open AccessArticle

Anti-Swaying Control Strategy of Ship-Mounted 3-RCU Parallel Platform Based on Dynamic Gravity Compensation

by Zhiyuan Lv, Pengfei Liu, Donghong Ning and Shuqing Wang

Machines 2024, 12(3), 209; https://doi.org/10.3390/machines12030209 - 21 Mar 2024

Viewed by 952

Abstract

It is essential to ensure stability during marine transportation or the installation of high center of gravity loads. The heavy loads increase gravity disturbance, affecting the steady-state-error control of the multiple degrees of freedom (DOFs) motion compensation platform. In this paper, we propose [...] Read more.

It is essential to ensure stability during marine transportation or the installation of high center of gravity loads. The heavy loads increase gravity disturbance, affecting the steady-state-error control of the multiple degrees of freedom (DOFs) motion compensation platform. In this paper, we propose a proportional derivative (PD) controller with dynamic gravity compensation (PDGC) for a 3-RCU (revolute–cylindrical–universal) parallel platform to improve the control effect of marine motion compensation for high center of gravity loads. We introduce an evaluation parameter of load stability and a weighting coefficient of anti-swaying control to tune the controller performance. The controller can set its control target between the two, keeping the load contact surface level and allowing the load center of gravity with the least movement. By deriving the Jacobian matrix, the gravity disturbance in the joint space is calculated and is compensated in the controller. First, we verify the control superiority of this controller over the PD controller under sinusoidal excitation in simulation and validate the effectiveness of the proposed anti-swing strategy. Then, the experiments are conducted with random excitation. The root mean square (RMS) value of the load’s residual angle with the proposed controller is reduced to 32.2% and 17.6% in two directions, respectively, compared with the PD controller under class 4 sea state excitation. The proposed method is effective for the anti-swaying control of ship-mounted 3-RCU parallel platforms. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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17 pages, 4925 KiB

Open AccessArticle

Design and Control of Autonomous Flying Excavator

by Arif Zaman and Jaho Seo

Machines 2024, 12(1), 23; https://doi.org/10.3390/machines12010023 - 29 Dec 2023

Cited by 1 | Viewed by 1310

Abstract

This study presents a drone-based excavation platform prototype with the key objectives of balancing stability during excavation, sensing, and digging the soil pile autonomously without human intervention. The whole platform was first designed in CAD software, and then each part of the excavator [...] Read more.

This study presents a drone-based excavation platform prototype with the key objectives of balancing stability during excavation, sensing, and digging the soil pile autonomously without human intervention. The whole platform was first designed in CAD software, and then each part of the excavator assembly was 3D printed by using PLA filament. The physical system was then combined with numerous electronic components and linked to various software applications for a drone to perform autonomous excavations. Pixhawk Orange Cube served as the main controller for the drone, while Nvidia Jetson Nano was used for processing data and controlling the tip of the bucket at a specified location for the autonomous excavator. Two scenarios were considered to validate the functionality of the developed platform. In the first scenario, the drone flies independently to a construction site, lands, senses the soil, excavates it, and then travels to another location specified by the mission to deposit the soil. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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17 pages, 3940 KiB

Open AccessArticle

Adaptive Neuro-Fuzzy Control of Active Vehicle Suspension Based on

H_{2}

and

H_{\infty}

Synthesis

by Jaffar Seyyed Esmaeili, Ahmad Akbari, Arash Farnam, Nasser Lashgarian Azad and Guillaume Crevecoeur

Machines 2023, 11(11), 1022; https://doi.org/10.3390/machines11111022 - 14 Nov 2023

Viewed by 1127

Abstract

This paper addresses the issue of a road-type-adaptive control strategy aimed at enhancing suspension performance.

H_{2}

synthesis is employed for modeling road irregularities as impulses or white noise, minimizing the root mean square (RMS) of performance outputs for these specific road types. [...] Read more.

This paper addresses the issue of a road-type-adaptive control strategy aimed at enhancing suspension performance.

H_{2}

synthesis is employed for modeling road irregularities as impulses or white noise, minimizing the root mean square (RMS) of performance outputs for these specific road types. It should be noted, however, that this approach may lead to suboptimal performance when applied to other road profiles. In contrast, the

H_{\infty}

controller is employed to minimize the RMS of performance outputs under worst-case road irregularities, taking a conservative stance that ensures robustness across all road profiles. To leverage the advantages of both controllers and achieve overall improved suspension performance, automatic switching between these controllers is recommended based on the identified road type. To implement this adaptive switching mechanism, manual switching is performed, gathering input–output data from the controllers. These data are subsequently employed for training an Adaptive Neuro-Fuzzy Inference System (ANFIS) network. This elegant approach contributes significantly to the optimization of suspension performance. The simulation results employing this novel ANFIS-based controller demonstrate substantial performance enhancements compared to both the

H_{2}

and

H_{\infty}

controllers. Notably, the ANFIS-based controller exhibits a remarkable 62% improvement in vehicle body comfort and a significant 57% enhancement in ride safety compared to passive suspension, highlighting its potential for superior suspension performance across diverse road conditions. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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18 pages, 2975 KiB

Open AccessArticle

A Reference Governor with Adaptive Performance for Quadrotors under Safety Constraints

by Panagiotis S. Trakas, Andreas Tantoulas and Charalampos P. Bechlioulis

Machines 2023, 11(11), 984; https://doi.org/10.3390/machines11110984 - 24 Oct 2023

Viewed by 1135

Abstract

This paper presents a novel robust reference governor (RG) for trajectory tracking of quadrotors. The proposed scheme is characterized by low computational complexity and straightforward gain selection. Moreover, it considers safety constraints regarding speed limits and ensures the stability and the proper operation [...] Read more.

This paper presents a novel robust reference governor (RG) for trajectory tracking of quadrotors. The proposed scheme is characterized by low computational complexity and straightforward gain selection. Moreover, it considers safety constraints regarding speed limits and ensures the stability and the proper operation of the closed-loop system. The proposed scheme imposes user-specified performance attributes on the evolution of the tracking error when the safety constraints allow it. When these constraints are at risk of violation, the proposed RG provides a relaxation of the predefined performance specifications to ensure the stability of the plant. Lyapunov analysis proves the boundedness of the closed-loop signals, while its efficacy is further clarified and verified via extensive comparative experimental results against a well-established PI regulator. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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19 pages, 5322 KiB

Open AccessArticle

Bond-Graph-Based Approach to Teach PID and Sliding Mode Control in Mechatronics

by Zenan Guo, Péter Korondi and Péter Tamás Szemes

Machines 2023, 11(10), 959; https://doi.org/10.3390/machines11100959 - 14 Oct 2023

Viewed by 1414

Abstract

The main contribution of this article is creating synergy between subjects; this means that students use the same graphical tool in several subjects. So far, the bond graph has not been used in control theory, but it is the “native language” of mechatronics [...] Read more.

The main contribution of this article is creating synergy between subjects; this means that students use the same graphical tool in several subjects. So far, the bond graph has not been used in control theory, but it is the “native language” of mechatronics engineers, so we would like to introduce it into the teaching of control theory. The bond graph method is proposed as a novel teaching method to teach mechatronics subjects in the paper. The bond graph is a graphical alternative to ordinary differential equations from a mathematical standpoint. Traditionally, control theory employs ordinary differential equations, as they are familiar to control theorists. However, mathematically, both approaches are equivalent but require a slightly different approach in their application. This article highlights the mathematical similarities between the two approaches while emphasizing the distinctions in graphical representation. Another contribution is that the PID and sliding mode controller are represented using the bond graph method. In the meantime, through the use of practical examples, we effectively illustrate how the same problem can be solved using either approach. In the training materials, the PID controller and an adaptive robust sliding mode controller (ARSMC) with the bond graph are utilized as examples to demonstrate synergy in mechatronics. Finally, we present proof that mechatronic engineers achieve superior outcomes when utilizing the bond graph approach, based on test results from undergraduate students. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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21 pages, 7233 KiB

Open AccessArticle

Intelligent-PID with PD Feedforward Trajectory Tracking Control of an Autonomous Underwater Vehicle

by Zafer Bingul and Kursad Gul

Machines 2023, 11(2), 300; https://doi.org/10.3390/machines11020300 - 17 Feb 2023

Cited by 21 | Viewed by 4423

Abstract

This paper investigates the model-free trajectory tracking control problem for an autonomous underwater vehicle (AUV) subject to the ocean currents, external disturbances, measurement noise, model parameter uncertainty, initial tracking errors, and thruster malfunction. A novel control architecture based on model-free control principles is [...] Read more.

This paper investigates the model-free trajectory tracking control problem for an autonomous underwater vehicle (AUV) subject to the ocean currents, external disturbances, measurement noise, model parameter uncertainty, initial tracking errors, and thruster malfunction. A novel control architecture based on model-free control principles is presented to guarantee stable and precise trajectory tracking performance in the complex underwater environment for AUVs. In the proposed hybrid controller, intelligent-PID (i-PID) and PD feedforward controllers are combined to achieve better disturbance rejections and initial tracking error compensations while keeping the trajectory tracking precision. A mathematical model of an AUV is derived, and ocean current dynamics are included to obtain better fidelity when examining ocean current effects. In order to evaluate the trajectory tracking control performance of the proposed controller, computer simulations are conducted on the LIVA AUV with a compelling trajectory under various disturbances. The results are compared with the two degrees-of-freedom (DOF) i-PID, i-PID, and PID controllers to examine control performance improvements with the guaranteed trajectory tracking stability. The comparative results revealed that the i-PID with PD feedforward controller provides an effective trajectory tracking control performance and excellent disturbance rejections for the entire trajectory of the AUV. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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Review

Jump to: Research

41 pages, 4940 KiB

Open AccessReview

A Review on the Applications of Dual Quaternions

by João Gutemberg Farias, Edson De Pieri and Daniel Martins

Machines 2024, 12(6), 402; https://doi.org/10.3390/machines12060402 - 12 Jun 2024

Viewed by 416

Abstract

This work explores dual quaternions and their applications. First, a theoretical construction begins at dual numbers, extends to dual vectors, and culminates in dual quaternions. The physical foundations behind the developed theory lie in two important fundamentals: Chasles’ Theorem and the Transference Principle. [...] Read more.

This work explores dual quaternions and their applications. First, a theoretical construction begins at dual numbers, extends to dual vectors, and culminates in dual quaternions. The physical foundations behind the developed theory lie in two important fundamentals: Chasles’ Theorem and the Transference Principle. The former addresses how to represent rigid-body motion whereas the latter provides a method for operating on it. This combination presents dual quaternions as a framework for modeling rigid mechanical systems, both kinematically and kinetically, in a compact, elegant and performant way. Next, a review on the applications of dual quaternions is carried out, providing a general overview of all applications. Important subjects are further detailed, these being the kinematics and dynamics of rigid bodies and mechanisms (both serial and parallel), control and motion interpolation. Discussions regarding dual quaternions and their applications are undertaken, highlighting open questions and research gaps. The advantages and disadvantages of using dual quaternions are summarized. Lastly, conclusions and future directions of research are presented. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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17 pages, 408 KiB

Open AccessEditor’s ChoiceReview

Survey on Physiological Computing in Human–Robot Collaboration

by Celal Savur and Ferat Sahin

Machines 2023, 11(5), 536; https://doi.org/10.3390/machines11050536 - 9 May 2023

Cited by 1 | Viewed by 2235

Abstract

Human–robot collaboration has emerged as a prominent research topic in recent years. To enhance collaboration and ensure safety between humans and robots, researchers employ a variety of methods. One such method is physiological computing, which aims to estimate a human’s psycho-physiological state by [...] Read more.

Human–robot collaboration has emerged as a prominent research topic in recent years. To enhance collaboration and ensure safety between humans and robots, researchers employ a variety of methods. One such method is physiological computing, which aims to estimate a human’s psycho-physiological state by measuring various physiological signals such as galvanic skin response (GSR), electrocardiograph (ECG), heart rate variability (HRV), and electroencephalogram (EEG). This information is then used to provide feedback to the robot. In this paper, we present the latest state-of-the-art methods in physiological computing for human–robot collaboration. Our goal is to provide a comprehensive guide for new researchers to understand the commonly used physiological signals, data collection methods, and data labeling techniques. Additionally, we have categorized and tabulated relevant research to further aid in understanding this area of study. Full article

(This article belongs to the Special Issue Control and Mechanical System Engineering)

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