Mechatronics最新文献

英文中文

Mass flow control using estimated output feedback in semiconductor processes

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-26 DOI: 10.1016/j.mechatronics.2025.103320

Kotaro Takijiri, Kazuki Nakata, Daisuke Hayashi

In the semiconductor manufacturing, process gas switching during atomic layer deposition and etching is critical for improving throughput. Thermal mass flow controller (MFC) used in this process requires a fast flow response. However, the slow response of thermal flow sensor leads to issue under transient conditions. Specifically, the observable flow value and the actual flow deviate, resulting in overshoot in the flow supplied to the chamber. To mitigate this issue, thermal flow response lag can be compensated through deviation operation. However, this method amplifies sensor noise and degrades flow stability, creating a trade-off between response time and stability. To address these challenges, this study proposes a feedback control system that employs an estimated output instead of direct sensor measurements, enabling a fast response with reduced noise and eliminating steady-state errors. The effectiveness of the proposed control scheme is validated experimentally.

引用次数: 0

High-precision and high-speed flow rate control with nonlinear disturbance compensation using valve body position feedback

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-26 DOI: 10.1016/j.mechatronics.2025.103317

Koki Hattori, Wataru Ohnishi, Takafumi Koseki

Pneumatic valves play a crucial role in controlling flow rates across various industrial applications. This study aims to achieve faster and more precise gas flow rate control to improve throughput and product quality. However, inherent nonlinearities such as solenoid hysteresis and compressible fluid dynamics degrade the control performance of pneumatic valves. To address these challenges, this study proposes a mass flow rate control system incorporating an inner feedback loop for valve body position control to compensate for nonlinear disturbances. Furthermore, a data-driven feedforward control approach based on iterative learning control (ILC) is implemented to mitigate repetitive disturbances and enhance flow rate response speed. Experimental validation demonstrates that the inner feedback loop effectively reduces steady-state error, while the proposed feedforward control achieves a 9 ms settling time, 98% faster than conventional industrial control using the same hardware.

引用次数: 0

Trade-off between flight performance and energy consumption of a quadrotor

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-24 DOI: 10.1016/j.mechatronics.2025.103316

Augusto H.B.M. Tavares , Saulo O.D. Luiz , Tiago P. Nascimento , Antonio M.N. Lima

This paper studies analytically and quantitatively the influence of the power source on the dynamic performance of the altitude control system of a quadrotor powered by an electrochemical battery. This paper also proposes the formulation of the altitude control system design as a constrained optimization problem in which the drone, actuators, control law, and electrochemical battery models are considered, to define a trade-off between the power consumption rate and the closed-loop dynamic performance loss. An analytical representation of the effect of the battery discharge over the altitude dynamics is obtained through a linear approximation, enabling an analysis of the system poles. The problem of designing an altitude controller is then posed as a constrained optimization problem that can include the battery as a factor. A comparison of the error transient response between the cases of the battery-unaware controller design and the battery-aware controller design is performed in simulations and experimental flight tests. The results lead to the following conclusions: i. the analytical demonstration agrees with the worse performance observed in the in-flight dynamics as the battery discharges and ii. through a battery-aware controller design approach this effect can be diminished, at the cost of a trade-off in the battery discharge rate.

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引用次数: 0

Optimal design and dynamic trajectory planning of a 2-DOF cable-suspended palletizing robot with parallelogram cable loop

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-23 DOI: 10.1016/j.mechatronics.2025.103330

Hanqing Liu , Jinhao Duan , Zhufeng Shao , Stéphane Caro

To fabricate high speed, vast workspace, energy saving, and light weight of the logistics equipment, this paper proposes geometric and trajectory optimization methods for the cable-suspended parallel robot (CSPR), which is a two-degree-of-freedom (2-DOF) robot with a parallelogram cable loop, realizing the efficient palletizing operation with dynamic trajectories. Based on kinematic and dynamic models, the Torsion Resistance Ability Index (TRAI) and Torsion Resistance Consumption Index (TRCI) are proposed to indicate the torsion resistance performance of the CSPR with the parallelogram cable loop. A geometric optimization method is established with the reference dynamic trajectory, which provides an approach to carry out the optimal design of the CSPRs considering dynamic trajectories for the first time. For industrial palletizing, a planning method on the dynamic trajectory is proposed considering the obstacle avoidance based on the Fourier and Polynomial models. A prototype of the 2-DOF CSPR is established, and the palletizing experiments are carried out, providing a novel high-efficiency palletizing robot and technology.

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引用次数: 0

Data association leveraging extrinsic parameter consistency for multi-object detection in maritime environment

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-19 DOI: 10.1016/j.mechatronics.2025.103318

Jonghwi Kim , Sol Han , Jinwhan Kim

This paper presents a novel data association method utilizing extrinsic parameter consistency, designed to improve the detection and tracking of multiple objects by fusing camera and marine radar measurements. The method addresses the challenges in dynamic maritime environments by leveraging the consistency of extrinsic parameters. To mitigate ambiguities in determining these parameters, a new cost function considering the costs associated with all possible pairs in a given combination is introduced. The constraints related to the alignment and sequencing of measured bearings are also integrated, and dynamic programming is employed to enhance computational efficiency. The enhancements in accuracy and computational speed by the proposed method have been validated using datasets obtained from real-sea field experiments.

引用次数: 0

A singularity-restrained kinesthetic teaching method for collaborative robots

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-12 DOI: 10.1016/j.mechatronics.2025.103313

Chunxin Li, Jianhua Wu, Zhenhua Xiong

Collaborative robots play an indispensable role in both industrial and service sectors. Kinesthetic teaching technology allows users to program robots through intuitive hand-guiding actions, endowing collaborative robots with convenient deployment capabilities. However, such manual guidance may bring the robot close to singularities, as users primarily focus on the motion of the end-effector, which leads to performance degradation and poses a challenge to task reliability. This paper proposes a kinesthetic teaching method that avoids singularities in Cartesian space. The advantage of this method is that it only restrains the robot from approaching singularities while having no effects in the rest of the workspace by asymmetrically adjusting the mapping relationship between hand-guiding force and end-effector velocity. Experiments have been conducted on all possible singularities of a 6-DOF robot. The results indicate that the proposed method effectively mitigates uncoordinated motion, and the operational performance of the robot has been enhanced.

引用次数: 0

Transcending the acceleration-bandwidth trade-off: Over-actuated precision motion stages with selective compliance and servo stiffness

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-11 DOI: 10.1016/j.mechatronics.2025.103314

Jingjie Wu, Lei Zhou

In today’s precision positioning systems, there exists a fundamental trade-off between control bandwidth and achievable acceleration due to the structural material’s stiffness-to-weight ratio limit and existing control techniques. This trade-off severely limits the throughput of photolithography machines and wafer inspection systems for integrated circuit manufacturing, which directly depends on the acceleration and control performance of the wafer and photomask positioning stages. Aiming to break this trade-off and to enable new lightweight stages with further enhanced acceleration without sacrificing control performances, this paper proposes a novel hardware and control co-design paradigm for over-actuated precision positioning stages that integrates servo-stiffness and selected compliance. The key idea is to (a) stiffen the component’s flexible dynamics through servo-stiffness, i.e., actively control the structure’s flexible dynamics using additional actuators and sensors, and (b) smartly introduce structural compliance in the actively controlled flexible modes to reduce weight and to facilitate controller synthesis. A sequential design optimization framework for the proposed methodology is presented, and an over-actuated magnetically levitated planar motion stage embodying the proposed approach, which we call the FleXstage, is designed and built for performance evaluation. Simulation shows that the proposed design provides 24% reduced weight and 2.4 times control bandwidth improvement compared to a baseline lightweight stage, and experimental results of the FleXstage prototype align well with simulation predictions. These results demonstrate the feasibility and potential of the proposed methodology.

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引用次数: 0

Lifted frequency-domain identification of closed-loop multirate systems: Applied to dual-stage actuator hard disk drives

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-04-09 DOI: 10.1016/j.mechatronics.2025.103311

Max van Haren , Masahiro Mae , Lennart Blanken , Tom Oomen

Frequency-domain representations are crucial for the design and performance evaluation of controllers in multirate systems, specifically to address intersample performance. The aim of this paper is to develop an effective frequency-domain system identification technique for closed-loop multirate systems using solely slow-rate output measurements. By indirect identification of multivariable time-invariant representations through lifting, in combination with local modeling techniques, the multirate system is effectively identified. The developed method is capable of accurate identification of closed-loop multirate systems within a single identification experiment, using fast-rate excitation and inputs, and slow-rate outputs. Finally, the developed framework is validated using a benchmark problem consisting of a multivariable dual-stage actuator from a hard disk drive, demonstrating its applicability and accuracy.

引用次数: 0

KOU-III: A bipedal robot with quadrotor-assisted locomotion

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-03-24 DOI: 10.1016/j.mechatronics.2025.103310

Xianwu Zeng , Lishu Huang , Guoteng Zhang , Yibin Li

This paper presents KOU-III, a bipedal robot prototype featuring quadrotor-assisted locomotion. With three rotary joints per leg supplemented by four rotor actuators, the system integrates a total of 10 independent actuators. The objective is to enhance the robot’s motion performance through quadrotor assistance rather than achieving multimodal locomotion. In the prototype design, we improved the rigidity and compactness of the knee joint actuator by modifying the cantilever structure of the planetary carrier in the reducer to a bridge-like design. A simple motion control strategy was then developed to enable the robot to perform standing, walking, and jumping motions. Experimental results demonstrate that quadrotor assistance significantly improves both the stability and motion performance of the bipedal robot.

引用次数: 0

Dynamic error budgeting based robust system and control co-design for active vibration isolation systems

IF 3.1 3区计算机科学 Q2 AUTOMATION & CONTROL SYSTEMS

Mechatronics

Pub Date : 2025-03-21 DOI: 10.1016/j.mechatronics.2025.103309

Sil T. Spanjer, Hakan Köroğlu, Wouter B.J. Hakvoort

This paper proposes a novel method to optimize active vibration isolation systems based on

H_{2}

-criteria using the dynamic error budgeting framework and

H_{\infty}

constraints to guarantee robust stability. This method explicitly takes into account all noise sources and disturbances present in active vibration isolation systems. The dynamic error budget is interpreted as an

H_{2}

optimal control problem with a specific set of input weighting functions, that are models of the input signal spectra. This is extended with

H_{\infty}

constraints to guarantee stability robustness of the controller. The constrained optimization problem is solved in a structured control setting, with a non-smooth sub-gradient descent method. This is used to optimize the controller and system parameters simultaneously. First an explorative study is done for a single axis active vibration isolation system, and it is shown that the performance improves significantly relative to a passive vibration isolation system and a benchmark active vibration isolation system. The optimal control formulation is thereafter applied to an experimental system, and performance improvements are obtained by a factor 2.3–4.1 in internal deformation power, and 2.9–13.7 in sensitive payload acceleration power with respect to the previous controller based on engineering intuition.

本文提出了一种基于 H2 标准的主动隔振系统优化新方法，利用动态误差预算框架和 H∞ 约束来保证鲁棒稳定性。该方法明确考虑了主动隔振系统中存在的所有噪声源和干扰。动态误差预算被解释为一个 H2 最佳控制问题，其中包含一组特定的输入加权函数，即输入信号频谱模型。该问题通过 H∞ 约束进行扩展，以保证控制器的稳定性和鲁棒性。在结构化控制设置中，采用非平滑子梯度下降法解决约束优化问题。这种方法可同时优化控制器和系统参数。首先对单轴主动隔振系统进行了探索性研究，结果表明，与被动隔振系统和基准主动隔振系统相比，该系统的性能有了显著提高。随后，将优化控制公式应用于实验系统，与之前基于工程直觉的控制器相比，内部变形功率提高了 2.3-4.1 倍，敏感有效载荷加速度功率提高了 2.9-13.7 倍。

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引用次数: 0

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