Proposed Position Control Scheme Research Articles

Development of a position control scheme for rotating sensor unit attached to in-pipe robot

In this article, we propose a position control scheme for the rotation axis of a rotating ultrasonic sensor unit with a position adjustment mechanism. The objective of the control is to adjust the position of the rotation axis of the ultrasonic sensor such that it can coincide with the center of a pipe. To realize the above objective, we provide a method to measure the vertical and horizontal positions of the rotation axis in a pipe. Using the measurements, we propose a position controller for the rotation axis. By carrying out experiments, we investigate the usefulness of the developed mechanism and the proposed position controller. As a result, it is shown that the proposed position control scheme ensures good performance.

토크 각도제어기법을 적용한 스테핑 전동기의 위치제어

This paper presents high speed position controller using stepping motor. The proposed position controller has close loop and open loop mode. In the high speed region, torque angle which is controlled by PI controller and memory based look-up table, is used to keep the reference position. The memory based look-up table produces a torque angle according to motor speed, and the PI controller can compensate the torque angle error. So, the fast dynamic response can be expected in the same position error. The open loop control mode which is divided by 3-modes control the actual position in the low speed and small position error. Each open loop modes are designed to reduce position error and dynamic brake in the stop command. The proposed position control scheme is verified by the practical stepping motor.

Robust balanced control of LPMSM servo drive with mass identification and large command change

Robust position control for a linear permanent-magnet synchronous motor servo drive is presented, considering the constituted component match under unknown mass and large command change. First, a field-weakening forcing current control scheme is developed to yield close current transient tracking response. In the proposed position control scheme, a cascaded two-degrees-of-freedom controller is quantitatively designed, and an internal robust model following controller (RMFC) is arranged to let the prescribed response be preserved under varying plant parameters and operating conditions. Then an identification scheme is devised to obtain a mass estimate from the compensating control signal generated by the RMFC. Finally, in making the large command positioning control, a match between the motor drive constituted components is considered. The amplitudes and/or ramping rate of step and ramp commands are determined according to the identified mass and the ratings of the inverter and motor. In this case, the response time is also predicable. Through applying the proposed simple command shaping control approach, quantitative positioning control performance under unknown mass and efficient capability utilisation of inverter and motor can be achieved, and the instability caused by nonlinearities under excessive saturation can be avoided.

Position control for ultrasonic motors using backstepping control and dead‐zone compensation with fuzzy inference

AbstractThe ultrasonic motor has comparatively high nonlinearity which varies with driving conditions, and possesses a variable dead zone in control input associated with the applied load torque. The dead zone is a problem for industrial applications and it is important to eliminate the dead zone in order to improve control performance. This paper proposes a new position control scheme for ultrasonic motors to overcome the dead zone. The dead zone is compensated by fuzzy inference, and backstepping control performs accurate position control. Compared with model reference adaptive control, which uses an augmented error, backstepping control can analyze a transient response. Mathematical models are formulated and experimental results show the effectiveness of the proposed position control scheme. © 2004 Wiley Periodicals, Inc. Electr Eng Jpn, 149(1): 69–77, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20016

Position Control for Ultrasonic Motors Using Backstepping Control and Dead-Zone Compensation with Fuzzy Inference

The ultrasonic motor has a heavy nonlinearity, which varies with driving conditions and possesses variable dead-zone in the control input associated with applied load torque. The dead-zone is a problem as an accurate positioning actuator for industrial applications and it is important to eliminate the dead-zone in order to improve the control performance. This paper proposes a new position control scheme of ultrasonic motors to overcome dead-zone employing model reference adaptive control (MRAC) with fuzzy inference. The dead-zone is compensated by fuzzy inference, and backstepping control performs accurate position control. As compared with MRAC which uses an augmented error, backstepping control can analyze a transient response. Mathematical models are formulated and experimental results are given to validate the proposed position control scheme.

Position control of ultrasonic motors using MRAC and dead-zone compensation with fuzzy inference

The ultrasonic motor has a heavy nonlinearity, which varies with driving conditions and possesses variable dead-zone in the control input associated with applied load torque. The dead-zone is a problem as an accurate positioning actuator for industrial applications and it is important to eliminate the dead-zone in order to improve the control performance. This paper proposes a new position control scheme of ultrasonic motors to overcome dead-zone employing model reference adaptive control with fuzzy inference. The dead-zone is compensated by fuzzy inference, whereas model reference adaptive control performs accurate position control. Mathematical models are formulated and experimental results are given to validate the proposed position control scheme.

Position control of ultrasonic motors using MRAC with dead-zone compensation

The ultrasonic motor has a heavy nonlinearity, which varies with driving conditions and possesses variable dead zone in the control input associated with applied load torque. This dead zone is a problem as an accurate positioning actuator for industrial applications and it is important to eliminate the dead zone in order to improve the control performance. This letter proposes a new position control scheme for ultrasonic motors, to overcome the load-torque-dependent dead zone employing model reference adaptive control with dead-zone compensation. The dead zone is compensated by an observer, whereas model reference adaptive control performs accurate position control. Mathematical models are formulated and experimental results are given to validate the proposed position control scheme.