Motion Control Of Motor Research Articles

Motion Control of Cylindrical Linear Induction Motor for Change of Load.

In recent years, linear motors are noticed as an excellent driving device of the straight pass transfer system. Advanced needs of transportation in linear motor is highly demanded in motor industries. This paper is to present motion control of a cylindrical linear induction motor (CLIM) by adjusting the frequency of V/f inverter. However, thrust characteristics of CLIM is governed by a complex non linear equation. To overcome this, first, the thrust characteristics is analyzed. And, the linearity of the thrust characteristic between thrust and slip frequency within the limited range is investigated. Then the reference acceleration range is decided based on the linearity range from this characteristics. Finally. Hx loop shaping control design method is applied and its usefulness has been demonstrated via experiments by comparing with conventional LQI control.

Adaptive robust precision motion control of linear motors with negligible electrical dynamics: theory and experiments

This paper studies the high performance robust motion control of an epoxy core linear motor, which has negligible electrical dynamics due to the fast response of the electrical subsystem. A discontinuous projection based adaptive robust controller (ARC) is first constructed. The controller theoretically guarantees a prescribed transient performance and final tracking accuracy in general, while achieving asymptotic tracking in the presence of parametric uncertainties. A desired compensation ARC scheme is then presented, in which the regressor is calculated using the reference trajectory information only. The resulting controller has several implementation advantages such as less online computation time, reduced effect of measurement noise, a separation of robust control design from parameter adaptation, and a faster adaptation rate. Both schemes are implemented and compared on an epoxy core linear motor. Extensive comparative experimental results are presented to illustrate the effectiveness and the achievable control performance of the two ARC designs.

Iterative learning control of permanent magnet linear motor with relay automatic tuning

In this paper, a feedforward–feedback control structure is proposed for precision motion control of a permanent magnet linear motor (PMLM) for applications which are inherently repetitive in terms of the motion trajectories. The control scheme utilises an efficient marriage of conventional PID feedback control and an intelligent feedforward control using an iterative learning control (ILC) algorithm. The PID feedback control stabilizes the PMLM system, while the ILC feedforward control enhances the trajectories tracking performance by capitalising on the experience gained from the repeated execution of the same operations. A relay automatic tuning method is developed and incorporated, so that an initial set of control settings may be automatically derived from a few cycles of self-induced controlled oscillations. This self-tuning feature enables the PMLM application system to be operated quickly near optimal conditions simply at a push-button efficiency. Extensive experimental results are presented to demonstrate the appeal and effectiveness of the proposed scheme.

Motion Control of Direct-Drive Motor by a Homogeneous ER Fluid

Since a direct-drive (DD) motor system doesn't have the reduction gear, the structure of the servo system can be simple and stiff. On the other hand, in the DD system, the disturbance torque directly influences the accuracy of the motor control. The high servo gain is effective and important for reducing the influence of the disturbance torque. However, the high servo control often makes the control system unstable or vibratory. Therefore, the servo gain must be lowered for assuring stability, and the influence of the disturbance becomes serious. In this study, the DD motor system using an ER fluid damper is discussed. By applying the ER damper to the DD motor system, it is possible to obtain the mechanical damping and to realize a high servo gain in the motion control. Finally, the effectiveness of the proposed system is confirmed experimentally.

Special Issue on Assistive Device Technologies

Mechatronics is one of the most powerful technologies to overcome various industrial and social problems arising in the 21st century, for example, realization of the recycle manufacturing system, global consideration on the environment, development of human-oriented technology. The 3rd International Conference on Advanced Mechatronics (ICAM’98)-Innovative Mechatronics for the 21st Century hass been held in Okayama August 3-6, 1998, following the 1st and 2nd held in Tokyo in 1988 and 1993, sponsored by the Japan Society of Mechanical Engineers. The purpose of the conference is to promote the creation of new technologies and industries such as advanced robotics and human-oriented technology for the coming 21st century. Two plenary talks and 35 technical sessions including 11 specially organized sessions were opened. In technical sessions, a total of 149 papers was presented, of which 61 papers were in organized sessions and 88 papers in general sessions. Some 47 papers came from 17 countries abroad and 102 papers from Japan. A number of registered participants excluding invited guests was 40 from other countries and 163 from Japan. After the technical program, the Advanced Robotics and Mechatronics symposium was held for tutorial reviews of future robotics and mechatronics, mainly focusing on ""human collaboration"" technology. More than 100 persons attended the symposium. Organized sessions included Analysis and Control of Robot Manipulators, Modeling and Control of Nonholonomic Underactuated Systems, Human Perspective Characteristics and Virtual Reality, Robotic Hand Design Grasping and Dexterous Manipulation, Healthcare Robotics, Advanced Fluid Power Control Technology, Advanced Robot Kinematics, Human Directed Robotics, Computer Support for Mechatronics System Design, Robotic Control, and Motion Control of Special Motors. Robotics was a main subject, but fluid power technology, fundamental motion control technology, and so on were also discussed. “Human collaboration” technology dealing with interaction between humans and robots attracted great attention from many participants. General sessions included Manufacturing, Vision, Micro Machine, Electric Actuator, Human-Robot Interface, Processing Technology, Fluid Actuator, Legged Locomotion, Control Strategy, Soft-Computing, Vehicle, Automation for Agriculture, Robot Force Control, Vibration, and Robot Application. Many studies have been presented over comprehensive subjects. This special issue has been organized by editing the papers presented at ICAM’98 for widely distributing the significant results of the conference. I would like to thank the authors in this special issue who have contributed their updated papers. Also, I would like to thank to Prof. Makoto Kaneko (Hiroshima University), whose work has been indispensable in organizing this special issue.

High-performance motion control of an induction motor with magnetic saturation

Generalizes the authors' work on high-performance control of induction motors to machines that exhibit significant magnetic saturation. The controller design is based on the standard d-q model of the induction motor which has been modified to account for the saturation of the iron in the main (magnetic) path of the machine. An input-output linearization controller is used to provide independent (decoupled) control of the speed and flux. With this controller, the flux reference becomes an extra degree of freedom for the designer to help achieve performance objectives. Taking into account saturation along with the voltage and current constraints, the flux reference is chosen to achieve the optimal torque (maximum for acceleration and minimum for deceleration) at any given speed. Experimental results are given to demonstrate the input-output controller's effectiveness in providing the tracking of a given position and speed trajectory while simultaneously tracking the optimal flux reference. The set of experiments are fast point-to-point motion control moves with an inertial load comparing the input-output controller based on the saturated magnetics model with that based on the linear magnetics model.

Nonlinear Control of Servo - Systems Actuated by Permanent-Magnet Synchronous Motors

A motion control problem for electric drives and servo-systems actuated by permanent-magnet synchronous motors is studied. Using a complete nonlinear model in machine variables and applying the offered nonlinear mapping control framework, an innovative synthesis procedure is introduced to design the robust bounded controllers to ensure precise tracking and disturbance rejection. These control algorithms are different compare to existing structures, and the synthesized new class of nonlinear controllers maps the error vector and state variables. Compared with commonly used algorithms, the dynamic performance is improved and robustness is guaranteed due to nonlinear feedback. The admissibility concept is employed because control bounds are imposed. It is shown that the robust tracking is ensured, stability and disturbance attenuation are guaranteed in the specified state-output and state-error sets for admissible disturbances, reference inputs, and parameter variations. Experimental verification of the developed control framework and digital implementation of the synthesized innovative controllers have a significant merit. This paper reports application features. The thorough researched innovative concept in motion control of permanent-magnet synchronous motors together with commercially available advanced hardware are applied, and experiments are performed to validate the results.

Learning Enhanced Motion Control of Permanent Magnet Linear Motor

This paper presents an approach towards learning enhanced motion control of permanent magnet linear motor (PMLM), suitable for applications involving repeated iterations of motion trajectories. The overall structure of the control consists of a feedback and a feedforward components. The PD feedback control provides for the main system stabilisation and an iterative learning control (ILC) algorithm is proposed to serve as a feedforward compensation to nonlinear and unknown dynamics and disturbances, thereby enhancing the improvement achievable with PD alone. A physical model is first derived for the Anorad’s LS-B linear motor and it serves as the basis for simulation study of the proposed control scheme. A comparison of the performance achieved with traditional PID is also provided to highlight the advantages of the additional intelligent feedforward mode.

Linear motor motion control using a learning feedforward controller

The design and realization of an online learning motion controller for a linear motor is presented, and its usefulness is evaluated. The controller consists of two components: (1) a model-based feedback component, and (2) a learning feedforward component. The feedback component is designed on the basis of a simple second-order linear model, which is known to have structural errors. In the design, an emphasis is placed on robustness. The learning feedforward component is a neural-network-based controller, comprised of a one-hidden-layer structure with second-order B-spline basis functions. Simulations and experimental evaluations show that, with little effort, a high-performance motion system can be obtained with this approach.

Closed loop low-velocity regulation of hybrid stepping motors amidst torque disturbances

To regulate the velocity of hybrid stepper motor motion control systems, a control law which exploits the nonlinear dynamics to create an analog positional control in conjunction with a traditional linear control is introduced. This nonlinear approach allows a much coarser position sensor to be used, including position estimates based on back EMF measurements. The form of the control law admits the use of a wide variety of compensators, whereas earlier laws use only velocity damping compensation. Two specific compensators, i.e., velocity damping and integral control are analyzed in detail, then compared to each other and to open loop microstepping control. It is shown that velocity damping allows the design of the eigenvalues of the closed loop system and provides a linear system approach about a specified operating point. Unfortunately, this operating point includes the value of external DC torque (drag) present, so the closed loop dynamics cannot be guaranteed amidst steady state torque fluctuations. Integral feedback (within a PID controller) improves upon velocity damping by not only allowing the design of the closed loop eigenvalues, but also by completely linearizing the system regardless of external DC torque values. Furthermore, the integral feedback produces zero steady state position error (as expected from linear control theory) and significantly decreases the tendency of the motor to lose step. Experimental results validate the analyses.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Motion control with induction motors

Induction motors (IM) provide a very wide speed range, mechanically robust and relatively low cost motion control option. An up-to-date summary of the status of induction motor motion control technology is the subject of this paper. The topics which this paper includes are as follows: basic motion control system requirements; field orientation instantaneous torque control principles for induction motors (FO-IM); current regulators for induction motor motion control; flux and torque regulators for induction motor motion control; self commissioning and continuous self-tuning for field orientation. Technology advances based on modern control and estimation theory have the potential to further enhance the capability of this important class of servo drive systems. >