Query:  of an Electromagnetically Levitated Linear Positioning System using 

Candidate papers:

abstract: The development of contactless electromagnetically levitated positioning systems is stimulated by the demand for vacuum compatible production machines. These vacuum compatible machines are used e.g. in the development of faster semiconductor chips and optical discs with larger data capacity. A novel vacuum compatible actuator is the IU module. The IU module allows wireless actuation in multiple degrees of freedom. The suspension force of this actuator is generated by permanent magnets allowing the force to be created with low power dissipation. In vacuum environments, low power dissipation is often a requirement due to the lack of convective cooling. In this research, the potential of this novel Multi DoF actuator is studied by integrating it into nanometre resolution contactless linear position positioning system, the Slider. This Slider has to fulfill the specifications of a linear positioning system used in a modern optical disc mastering production machine. In its most critical direction, the developed Slider using the IU modules realized a position stability of 0.12 nm (standard deviation) with a control strategy acting on the rigid body coordinates. When additional actuation capabilities of the IU module were used, the excitation of flexible modes in the Slider could be reduced. This allowed the positioning performance of the Slider to be improved to 58 pm (standard deviation) The challenges addressed in the research are the electromagnetic design of the actuator itself, as well as the integral mechatronic design and control of the linear positioning system.
author_names: D A H Laro
title: Mechatronic Design of an Electromagnetically Levitated Linear Positioning System using Novel Multi DoF Actuators
year: 2009

abstract: This paper considers the set point control problem of an uncertain six degree of freedom precision positioning system, where only position measurements are available. As a solution, we present an iterative output feedback control algorithm whose learning mechanism is based on the concept of contraction mapping. Besides stability and convergence, the presented analysis includes practical aspects associated with the algorithm implementation. In particular, it is shown that: 1) the system response due to the iterative process converges to an arbitrarily small neighborhood of the desired equilibrium point, and 2) the steady state response after each iteration is bounded inside the system traveling range. The presented control algorithm is demonstrated experimentally.
author_names: Sergei Basovich

Shai A Arogeti

Yonattan Menaker

Ziv Brand
title: Magnetically Levitated Six DOF Precision Positioning Stage With Uncertain Payload
venue: IEEE/ASME Transactions on Mechatronics
year: 2016

abstract: This paper presents the integrated design of a magnetically levitated dual stage positioning system to improve the bandwidth of traditional maglev positioning systems. The primary stage of the proposed dual stage system is a 6 DOF maglev positioning system, and a specifically designed flexure based actuator is utilized as the secondary stage to further compensate the error of primary stage. Compared with the primary maglev stage, the flexure based secondary stage owns the advantages such as high stiffness, high nature frequency, and non commutation. The plant and controller parameters of the secondary stage is integrally designed in this work, where various control/mechanical specifications are considered and formulated as the constraints in an optimization problem. The prototype of designed secondary stage is fabricated, and the experiments indicate that the bandwidth of the flexure based secondary stage is largely improved compared with the primary maglev stage.
author_names: Haiyue Zhu

Tat Joo Teo

Chee Khiang Pang

Wenyu Liang
title: Integrated design of a secondary stage for magnetically levitated dual stage positioning system
venue: 2017 IEEE International Conference on Advanced Intelligent Mechatronics (AIM)
year: 2017

abstract: This paper presents a novel design of six degree of freedom (6 DOF) magnetically levitated (maglev) positioner, where its translator and stator are implemented by four groups of 1 D Halbach permanent magnet (PM) arrays and a set of square coils, respectively. By controlling the eight phase square coil array underneath the Halbach PM arrays, the translator can achieve 6 DOF motion. The merits of the proposed design are mainly threefold. First, this design is potential to deliver unlimited stroke planar motion with high power efficiency if additional coil switching system is equipped. Second, multiple translators are allowed to operate simultaneously above the same square coil stator. Third, the proposed maglev system is less complex in regard to the commutation law and the phase number of coils. Furthermore, in this paper, an analytical modeling approach is established to accurately predict the Lorentz force generated by the square coil with the 1 D Halbach PM array by considering the corner region, and the proposed modeling approach can be extended easily to apply on other coil designs such as the circular coil, etc. The proposed force model is evaluated experimentally, and the results show that the approach is accurate in both single and multiple coil cases. Finally, a prototype of the proposed maglev positioner is fabricated to demonstrate its 6 DOF motion ability. Experimental results show that the root mean square error of the implemented maglev prototype is around 50 nm in planar motion, and its velocity can achieve up to 100 mm/s.
author_names: Haiyue Zhu

Tat Joo Teo

Chee Khiang Pang
title: Design and Modeling of a Six Degree of Freedom Magnetically Levitated Positioner Using Square Coils and 1 D Halbach Arrays
venue: IEEE Transactions on Industrial Electronics
year: 2017

abstract: This paper presents a generalized source modeling method, referred here as distributed multilevel current (DMC) models, utilizing equivalent magnetizing currents as local point sources to describe material effects of commonly used magnetic components. Unlike existing numerical methods, which solve for the magnetic fields from Maxwell's equations and boundary conditions, the DMC based method develops closed form solutions to the magnetic field and force problems, while allowing tradeoffs between computational speed and accuracy using a multilevel structure to discretize geometry and minimize modeling errors in the neighborhood around the point sources. Typical DMC models for volume and surface current elements, permanent magnets, electromagnets, iron plate, and induced eddy currents are derived and validated by comparing their magnetic fields and forces with known (analytical, numerical, and/or experimental) solutions. Results of benchmark comparison demonstrate that the DMC methods reduce the computation time of magnetic fields and forces by several orders as compared to exact solutions numerically integrated from the Biot Savart law and Lorentz force equation and finite element analysis. The DMC models were experimentally applied to identify the EM coil position and PM magnetization of a commercial PM linear synchronous motor validating their effects on its torque ripple.
author_names: Jungyoul Lim

Kok-Meng Lee
title: Distributed Multilevel Current Models for Design Analysis of Electromagnetic Actuators
venue: IEEE/ASME Transactions on Mechatronics
year: 2015

abstract: Several processes in chemical, pharmaceutical, biotechnology, and semiconductor industry require contactless levitation and rotation through a hermetically closed chamber wall. This paper presents a novel concept that combines crucial advantages such as high acceleration capability, large air gap, and a compact motor setup. The basic idea is to separate a homopolar bearing unit axially from a multipolar drive unit on two different height levels. Hence, the proposed concept is denominated as ldquomagnetically levitated two level motor.rdquo In this paper, the bearing and drive functionalities are explained in detail and design guidelines are given based on analytic equations and electromagnetic 3 D simulations. Furthermore, the influence of nonidealities such as saturation and coupling effects is evaluated and included in the design. Finally, extensive measurements on an experimental prototype exemplify the design considerations and prove the excellent performance of the new concept.
author_names: Philipp Karutz

Thomas Nussbaumer

Wolfgang Gruber

Johann Walter Kolar
title: Novel Magnetically Levitated Two Level Motor
venue: IEEE/ASME Transactions on Mechatronics
year: 2008

abstract: High precision magnetic levitation positioning systems are of great interest for many modern applications, because of their absolutely non contact operation and large planar travel ranges with precisions up to the nanometer range. In this article, a novel six degrees of freedom (6 DoF) magnetic levitation (maglev) system, which is based on repulsive levitation forces, is presented. Compared to other known solutions from the literature, this proposed concept allows a freely accessible mover from above in combination with decoupled levitation and propulsion forces. The maglev system consists of eight air core coils in order to realize a 6 DoF motion. The six axes position measurement is achieved by four eddy current sensors and four optical laser sensors. After a detailed explanation of the working principle, a decoupled 6 DoF dynamic model is derived and analyzed. Then, based on this dynamic model, simple proportional integral differential (PID) controllers are implemented in order to control the unstable behavior of the system. The aim of this article is to demonstrate the functionality of the proposed system. Thus, various experimental results, obtained from the prototype, were conducted to evaluate the dynamic performance of the maglev system. It will be shown that the position errors lie in the range of the sensor resolution and, thus, can be made as small as desired, depending on the applied sensor resolution.
author_names: Mousa Lahdo

Tom Jun -Prof Dr -Ing Strohla

Sergej Kovalev
title: Design and Implementation of an New 6 DoF Magnetic Levitation Positioning System
venue: IEEE Transactions on Magnetics
year: 2019

abstract: This paper presents a novel flexural based nano positioning actuator that has a positioning accuracy of 10 nm (limited by encoder resolution) throughout a range of 3 mm. A new dual magnet configuration is introduced to enhance this electromagnetically driven actuator in achieving 60 N/Amp in a compact configuration. In addition, a constant and evenly distributed magnetic flux density is obtained throughout 11 mm of air gap. A new mathematical model is presented to accurately predict the behavior of magnetic field within the effective air gap of this configuration. Complete analytical models for this actuator's electromagnetic drive and flexural bearing support element are presented. Lastly, a prototype of this actuator is developed for validating the established analytical models and verifying the claimed capabilities.
author_names: Tat Joo Teo

I-Ming Chen

Guilin Yang

Wei Lin
title: A Novel Actuator for High Precision Alignment in a Nano Imprint Multi Layers Interconnection Fabrication
venue: Proceedings 2007 IEEE International Conference on Robotics and Automation
year: 2007

abstract: This paper proposes a novel planar electromagnetic actuated positioning stage. The stage is suspended by the monolithic parallel flexure mechanism, which motion comes from the deformation of the flexure. A linear electromagnetic actuator which consists of a near uniform magnetic field and four coils is designed and implementation to provide the propelling force for 3 DOF motions. In order to suppress the vibration of the flexure suspension mechanism, an eddy current damper is designed and integrated with the electromagnetic actuator. The non contact damper is more advanced than the contact damper used in our previous researches. The design traveling range is 3 mm times 3 mm in planar motion. The experimental results show the vibration of the flexure mechanism could be suppressed by the designed eddy current damper. The results also show the regulation and tracking performance by a well designed robust adaptive sliding mode controller, which can overcome the disturbance and modeling uncertainty and guarantee a satisfactory performance.
author_names: Chih-Hsien Lin

Shao-Kang Hung

M -Y Chen

Shan-Tsung Li

Li-Chen Fu
title: A novel high precision electromagnetic flexure suspended positioning stage with an eddy current damper
venue: 2008 International Conference on Control, Automation and Systems
year: 2008

abstract: In this paper attention is given to the initial design and experimental verification of the novel IU shaped electromechanical actuator as a part of six degrees of freedom (6 DoF) contactless sliding system. Such a synergetic system is reached by integration of electromagnetic and mechanical structures of magnetic bearing and linear electromechanical actuator. Initially the performance of the electromagnetic module is examined. An analytical investigation of decoupled forces, originated from permanent magnets and suspension coils as functions of rotor position and current values in the control coils, is performed. Numerical results (the FEM models Maxwell 3D Ansoft Co. are validated by static measurements. Initial geometry is modified to demonstrate the improvement of the actuator performance.
author_names: A V Lebedev

Elena A Lomonova

P G van Leuven

John S Steinberg

D A H Laro
title: Analysis and initial synthesis of a novel linear actuator with active magnetic suspension
venue: Conference Record of the 2004 IEEE Industry Applications Conference, 2004. 39th IAS Annual Meeting.
year: 2004