Intelligent measurement and compensation of linear motor force ripple: a projection-based learning approach in the presence of noise

The microassembly of microelectromechanical systems from various micro-components requires the development of many new robotic capabilities. One of these capabilities is force control for handling micro-scale components with force control resolution on the order of micronewtons. In this paper, the force control of linear motor stages is discussed with application to the microassembly of MEMS. Linear motor stages provide an attractive solution for microassembly robots because they have a large working volume and can achieve high-precision positioning. However, the nonlinear friction and force ripple effects inherent in linear stages provide an obstacle to the required level of force control. A model of a single motor stage has been developed including dynamic friction effects. Based on this model, a robust nonlinear force controller has been designed to meet the microassembly requirements. The controller has been tested in simulation to demonstrate its effectiveness.

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Sub-Nanometer Positioning Combining New Linear Motor with Linear Motion Ball Guide Ways

International Journal of Automation Technology ◽

10.20965/ijat.2009.p0241 ◽

2009 ◽

Vol 3 (3) ◽

pp. 241-248

Author(s):

Jiro Otsuka ◽

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Toshiharu Tanaka ◽

Ikuro Masuda ◽

◽

...

Keyword(s):

Permanent Magnets ◽

Linear Motor ◽

General Motors ◽

Step Response ◽

Precision Positioning ◽

Positioning Device ◽

Ultra Precision ◽

New Type ◽

Force Ripple ◽

Flux Leakage

A new type of linear motor described in this paper has some advantages compared with the usual types of motors. The attractive magnetic force between the stator (permanent magnets) and mover (armature) is diminished almost to zero. The efficiency is better because the magnetic flux leakage is very small, the size of motor is smaller and detent (force ripple) is smaller than the general motors. Therefore, we think that this motor is greatly suitable for ultra-precision positioning as an actuator. An ultra-precision positioning device using this motor and liner motion ball guide ways is newly developed. Moreover, the positioning performance is evaluated by a positioning resolution, deviational and dispersion errors. As the results of repeated step response tests, the positioning resolution is 0.3 nm, the deviational error is -0.001nm and the dispersion error (3σ) is 0.29 nm. Consequently, the positioning device achieves sub-nanometer positioning. In addition, very large rigidity can be achieved.

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The Model-free Adaptive Composite Control Method for Permanent Magnet Linear Motor

International Journal of Interdisciplinary Telecommunications and Networking ◽

10.4018/ijitn.2015040103 ◽

2015 ◽

Vol 7 (2) ◽

pp. 30-44

Author(s):

Rongmin Cao ◽

Su Zhong ◽

Shizhen Liu

Keyword(s):

Permanent Magnet ◽

Control Method ◽

Controller Design ◽

Adaptive Controller ◽

Linear Motor ◽

Modeling And Control ◽

Composite Control ◽

Model Free ◽

Permanent Magnet Linear Motor ◽

Force Ripple

A composite control method based on the model-free adaptive control is applied to the position or speed control of the linear motor. The model-free adaptive controller (MFAC) broke through the classical PID controller design of linear framework, is a kind of new controller, it' structure is adaptive and a kind of integration of modeling and control method. The composite control method includes an adaptive feedforward compensator which is designed to eliminate or suppress the effects of inherent force ripple for a permanent magnet linear motor (PMLM). Simulation results show that compared with PID control, the proposed composite control algorithm is more effective for the strong coupling of nonlinear system and difficult to realize stable control. And the response performance of the system is realized.

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Design and Optimization of a Surface-Mounted Permanent-Magnet Linear Synchronous Motor with Maxwell ANSYS

Al-Khwarizmi Engineering Journal ◽

10.22153/kej.2019.01.005 ◽

2019 ◽

Vol 15 (3) ◽

pp. 1-15 ◽

Cited By ~ 4

Author(s):

Jamal Abdul-Kareem Mohammed ◽

Farag Mahel Mohammed ◽

Raghda'a Ahmed A. Ali

Keyword(s):

Permanent Magnet ◽

Linear Motor ◽

Iron Core ◽

Geometrical Parameters ◽

Solid Core ◽

Design And Optimization ◽

Output Force ◽

Permanent Magnet Linear Motor ◽

Optimum Model ◽

Force Ripple

Linear motor offers several features in many applications that require linear motion. Nevertheless, the presence of cogging force can deteriorate the thrust of a permanent magnet linear motor. Using several methodologies, a design of synchronous single sided linear iron-core motor was proposed. According to exact formulas with surface-mounted magnets and concentrated winding specification, which are relying on geometrical parameters. Two-dimensional performance analysis of the designed model and its multi-objective optimization were accomplished as a method to reduce the motor cogging force using MAXWELL ANSYS. The optimum model design results showed that the maximum force ripple was approximatrly reduced by 81.24%compared to the original model with a smaller ripple coefficient of 0.22. Likewise, the model was redesigned taking into consideration two cases; laminated core and solid core. It was found that the error between the analytical and numerical results of the output force did not exceed 0.0967%.

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