Positioning Control of DC Servomotor-Based Antenna Using PID Tuned Compensator

Direct current (DC) servomotor-based parabolic antenna is automatically positioned using control technique to track satellite by maintaining the desired line of sight for quality transmission and reception of electromagnetic wave signals in telecommunication and broadcast applications. With several techniques proposed in the literature for parabolic antenna position control, there is still a need to improve the tracking error and robustness of the control system in the presence of disturbance. This paper has presented positioning control of DC servomotor-based antenna using proportional-integral-derivative (PID) tuned compensator (TC). The compensator was designed using the control and estimation tool manager (CETM) of MATLAB based on the PID tuning design method using robust response time tuning technique with interactive (adjustable performance and robustness) design mode at a bandwidth of 40.3 rad/s. The compensator was added to the position control loop of the DC servomotor–based satellite antenna system. Simulations were carried out in a MATLAB environment for four separate cases by applying unit forced input to examine the various step responses. In the first and second cases, simulations were conducted without the compensator (PID TC) in the control loop assuming zero input disturbance and unit input disturbance. The results obtained in terms of time-domain response parameters showed that with the introduction of unit disturbance, the rise time improved by 36 % (0.525–0.336 s) while the peak time, peak percentage overshoot, and settling time deteriorate by 16.3 % (1.29–1.50 s), 43.5 % (34.7–49.8 %), and 7.6 % (4.35–4.68 s), respectively. With the introduction of the PIDTC for the third case, there was an improvement in the system’s overall transient response performance parameters. Thus to provide further information on the improved performance offered by the compensator, the analysis was done in percentage improvement. Considering the compensated system assuming zero disturbance, the time-domain response performance parameters of the system improved by 94.1, 94.7, 73.1, and 97.1 % in terms of rising time (525–30.8 ms), peak time (1,290–67.9 ms), peak percentage overshoot (34.7–9.35 %), and settling time (4.35–0.124 s), respectively. In the fourth case, the compensator’s ability to provide robust performance in the presence of disturbance was examined by comparing the step response performance parameters of the uncompensated system with unit input disturbance to the step response performance parameters of the compensated system tagged: with PID TC + unit disturbance. The result shows that PID TC provided improved time-domain transient response performance of the disturbance handling of the system by 91.0, 95.4, 80.0, and 93.1 % in terms of rising time (336–30.5 ms), peak time (1500–69.1 ms), peak percentage overshoot (34.7–10.0), and settling time (4.68–0.325 s), respectively. The designed compensator provided improved robust and tracking performance while meeting the specified time-domain performance parameters in the presence of disturbance.

Comparison and Speed Control of DC Motor and DC Servomotor Using IMC Based PID Controller

IMC based PID controllers are being used to speed control of DC motor and DC servomotor in industry. As this controller offer good performance comparitive to conventional controllers like PI, PID and Ziegler Nichols frequency method controllers. This paper presents the speed control of the DC motor and DC servomotor using PI, PID, Ziegler Nichols method and IMC-PID controllers, to realize the optimization of control action. A mathematical calculation of DC motor and DC servomotor has developed and simulations are carried out in MATLAB/ Simulink environment. From the results, it is observed that time domain parameters like rise time 0.6 secs, settling time 2 secs, speed for peak over shoot 1450, peak amplitude 1, with no oscillations using IMC-PID controller on DC motor. And for DC servomotor its rise time is 0.3 seconds, settling time is 1 second, speed for peak overshoot 1450 rpm, peak amplitude 1 with absence of oscillations by using IMC-PID controller

Estabilidad y diseño de un controlador LQR para un sistema Bola-Viga

This article presents the design of an LQR controller for a Ball-Beam system, as well as its stability analysis, the control of a Ball-Beam system is one of the most interesting for control engineering since it is a highly non-dynamic system linear. The objectives of this document focus on the performance of the system using an LQR control for different disturbances as well as obtaining the phase plans. The work starts with the modeling of the ballgirder system, which consists of two mechanical arms, a gear box and a DC servomotor, later the LQR control is designed, this allows simulation and obtaining the response of the controller under different conditions. In the system the input torque is generated from the DC servo motor to control the position of the ball on the beam, where the ball rolls freely on the beam. Performance analysis is performed using robust LQR and the performance characteristics of the system are presented. Finally, the stability analysis is carried out by plotting the phase planes.

Design and Test of a Microdestructive Tree-Ring Measurement System

Analysis of a tree ring is the primary method for determining the growth and age of a tree. In a microdestructive tree-ring measurement system, the tree under test is drilled with a microdrill at a constant rotating speed to detect the difference in density between the early and late wood, thereby realizing a microdestructive measurement of the tree-ring. The measurement system comprises a microdrill with a diameter of 3 mm, mechanical transmission, direct current (DC) servomotor, stepper motor, and control and detection circuit. The DC servomotor and stepper motor realize rotation and translation of the microdrill, respectively, through mechanical transmission. When the microdrill rotates and drills into the tree, the control and detection circuit samples and acquires the armature current of the DC servomotor, which is proportional to the resistance encountered by the drill bit and reflects the change in the density of the tree. The tree-ring number can be obtained by filtering the sampled original signals of the armature current using a finite impulse response (FIR) filtering algorithm. The annual rings of larch and fir tree discs were measured and tested using the designed system. It was observed that the average annual ring measurement accuracy of the larch discs reached 95.28%, while that of the fir discs was 84.16%. The diameter of the drill hole in the trunk was less than 3 mm after measuring the living wood, thereby achieving a microdestructive measurement of the tree-ring.

Parametric optimization-based design of PI controllers: application to a DC servomechanism

Purpose This paper aims to propose an analytical method for designing parametric optimization-based proportional integral (PI) controllers. Design/methodology/approach In this method, a performance index containing the weighted summation of the integral square of the error and its derivative is minimized. This performance index is analytically calculated in terms of the controller parameters by solving a Lyapunov equation. Then partial derivatives of the performance index with respect to controller parameters are calculated. Equating these partial derivatives to zero gives explicit relations for the PI controller parameters. Findings The experimental tests on a DC servomotor system are given to demonstrate the efficiency of the proposed method. Originality/value This paper proposes an analytical parametric optimization approach for designing PI controllers for the first time. The application of the proposed method in a laboratory experiment is examined.