Perfect Tracking Control Method Research Articles

Intersample Behavior Analysis of MIMO Multirate Feedforward Control depending on Selection of Input Multiplicities

Perfect tracking control method using multirate feedforward control is a very effective control method in high-precision positioning systems since this method provides zero tracking error for a nominal plant at every reference sampling point theoretically. When we design a multirate feedforward controller for a multi-input multi-output system, it is known that several types of controllers can be designed depending on how to select input multiplicities. Although multirate feedforward controllers provide perfect tracking at every reference sampling point theoretically, intersample behavior is different. In this paper, we propose the stable state trajectory generation method and the guideline to design an optimal multi-input multi-output multirate feedforward controller considering the 2-norm of control input and improve the intersample behavior. The effectiveness of the proposed method is verified in the simulation.

Perfect Tracking Control Method by Multirate Feedforward and State Trajectory Generation based on Time Axis Reversal

Perfect Tracking Control Method by Multirate Feedforward and State Trajectory Generation based on Time Axis Reversal

Preactuated multirate feedforward for a high-precision stage with continuous time unstable zeros

A plant with unstable zeros is known to be difficult to control because of initial undershoot of step response and unstable poles in its inversion system. There are two reasons why a plant has unstable zeros in the discrete time domain: 1) non-collocation of actuators and sensors, 2) discretization by zero-order-hold. Problem 2) has been solved by the perfect tracking control (PTC) method based on multirate feedforward control proposed by our research group. However, the conventional PTC method cannot achieve the perfect tracking for a plant with continuous time unstable zeros generated by 1) because of the divergence of the desired state trajectories. Preactuation Perfect Tracking Control (PPTC) method proposed by our group solves problem 1) by the state trajectory generation based on a time axis reversal. This paper verifies the effectiveness of PPTC by simulations and experiments in comparison with several single rate feedforward control methods.

時間軸反転による状態変数軌道生成とマルチレートフィードフォワードを用いた完全追従制御法

時間軸反転による状態変数軌道生成とマルチレートフィードフォワードを用いた完全追従制御法

A Study on High-Speed and High-Precision Tracking Control of Large-Scale Stage Using Perfect Tracking Control Method Based on Multirate Feedforward Control

In hard-disk-drive control, the perfect tracking control (PTC) method has already obtained high performance. Therefore, the first author and his group study the PTC scheme for improving the performance of large-scale stages. This paper presents an application of the PTC scheme to the tracking control of two different stages. The results from both simulations and experiments show that the PTC method outperforms the conventional rigid-body-mode-based feedforward method.

Application of Perfect Tracking Control to Large-Scale High-Precision Stage

In the positioning system of the large-scale high-precision stage, the primary resonance mode appears in low frequency, though large-scale high-precision stages are used in industrial fields. In recent years, our research group has applied the perfect tracking control (PTC) method which can design the perfect inverse system of the plant to a large-scale high-precision stage to improve the control performance. Moreover, a synchronous position control based on PTC method is proposed as application to several stages. In early sections, the application of the PTC method to a large-scale stage is introduced. In latter sections, the application to synchronous position control is introduced.

Short Span Seeking Control System of Hard Disk Drives Based on Pivot Friction Compensation

In this paper, we propose a precise short-span seeking control system based on the pivot friction compensation. The proposed compensator consists of the feed forward compensation with perfect tracking control method and feedback compensation with optimum friction compensation. The effectiveness of the proposed compensator is verified by using numerical simulation.

Control Method for IPMSM Based on Perfect Tracking Control Method and PWM Hold Model in Overmodulation Range

Interior permanent magnet motors (IPMSMs) are employed for the drive motors of electric and hybrid vehicles. Therefore, control method to be used in the overmodulation range of the inverter is important to achieve fast torque response and expand the operating range of the IPMSMs. In this paper, a control method based on perfect tracking control and the PWM (Pulse Width Modulation) hold model in the overmodulation range is proposed. Finally, simulations and experiments are performed to show the advantages of the proposed method.

MultiRate Predictive Control of Piezoelectric actuators

Piezoelectric materials show nonlinear hysteresis behaviour when they are under high electrical field and mechanical load. Fundamental study of PEA depicts that the Hysteresis effect deteriorate the tracking performance of The PEA. This paper proposes a nonlinear model which quantifies the Hysteresis nonlinearity generated in Piezoactuators in response to applied driving voltages. A novel perfect tracking control method based on multirate feedforward control is proposed which uses the nonlinear model to compensate mentioned limiting factors in PEA. In this study a multirate control method based on modified Prandtle-Ishlinskii operator as nonlinear model is implemented. It compensates rate dependant hysteresis nonlinearity in PEA. The controller structure has a simple design and can be quickly identified. The control system is capable to achieve suitable tracking control and it is convenient to use and can be quickly applied to the practical PEA applications. Experimental results are provided to verify the efficiency of the proposed method.

Perfect tracking control based on multirate feedforward control with generalized sampling periods

In this paper, a novel perfect tracking control method based on multirate feedforward control is proposed. The advantages of the proposed method are that: (1) the proposed multirate feedforward controller eliminates the notorious unstable zero problem in designing the discrete-time inverse system; (2) the states of the plant match the desired trajectories at every sampling point of reference input; and (3) the proposed controller is completely independent of the feedback characteristics. Thus, highly robust performance is assured by the robust feedback controller. Moreover, by generalizing the relationship between the sampling period of plant output and the control period of plant input, the proposed method can be applied to various systems with hardware restrictions of these periods, which leads to higher performance. Next, it is shown that the structure of the proposed perfect tracking controller is very simple and clear. Illustrative examples of position control using a DC servomotor are presented, and simulations and experiments demonstrate the advantages of this approach.

High performance perfect tracking control based on multirate feedforward / feedback controllers with generalized sampling periods

In this paper, a novel perfect tracking control method based on the multirate sampling control is proposed, in which the concepts of the two-degree-of-freedom control are employed. Moreover, by generalizing the multirate input and output sampling periods, the proposed method can match the restrictions of the sampling periods caused by the hardware, and achieve higher performance. The main results of this paper are 1) the perfect tracking performance is assured in the in the intersampling points, if the input multiplicity is increased, 2) higher feedback performance is achieved, if the output multiplicity is increased. Illustrative examples of position control using a dc servo motor are presented, and simulations and experiments demonstrate the advantages of this approach.