AC Servo Research Articles

Multi-motor average deviation coupling control strategy based on hyperbolic convergence law high-order sliding mode control using extended state sliding mode observer

This paper aims to develop a multi-motor synchronous drive control system for the direction of the width of the lifting arm of a catamaran. Firstly, we establish a mathematical model of permanent magnet synchronous motor and introduce the composition of AC servo control systems. We then analyze the sources of control interference in multi-motor drive systems. Based on the mean deviation coupling control strategy of multi-motor synchronous control, we design a speed tracking controller and a speed synchronization controller using hyperbolic convergence law high-order sliding mode control. Then, we design an extended state sliding mode observer to estimate the unmodeled dynamics of the system in real time. We prove the global stability of the controller using Lyapunov stability theory. Finally, the control model is simulated, and the results confirm the effectiveness of the multi-motor synchronization control method based on the hyperbolic convergence law of higher-order sliding mode control. The control method effectively mitigates the jitter associated with traditional sliding mode control and demonstrates improved synchronization and tracking performance.

Σ-X Series: AC Servo Drive for Achievement of Digital Solution

In recent years, AC servo drives have been required not only to play the role of high-speed and high-precision positioning devices but also as information devices that acquire various data through sensor networks. Our current flagship product: the Σ-X series, is a component that maximizes the performance of our customers' equipment and provides data acquisition functions to realize digital solutions such as preventive maintenance and failure prediction.

Design and Analysis of Automated Scum Removal and Filtering System for Jaggary Plant

An automated Scum Removal Machine is used to remove Scum produced during the production of Jaggery. Scum Removal is done by a manual method in our country. This project aims to develop an Automated Scum Removal Machine. The Scum removal machine can be adopted in the medium and large-sized jaggery production industry. This machine makes the process simple, easy and fast. It eases human effort and no requirement for skilled workers to operate the machine. It consists of the base, stands, leads screw, horizontal arm, thrust servo motor(0.5hp),shaft collectors, pan and multilevel filtration system.The stand and lead screw is mounted on the base and the horizontal is attached to the screw through the stand.The horizontal arm carriesa slow-speed AC servo motor and this AC servo motor runs the collector's through a vertical shaft. upward and downward movement of the arm is controlled by a lead screw which is controlled by switches.A multi-level filtration system is placed under the pan. The scum that is collected in the collector is lifted by raising the arm. Hence, the pure form of juice can be obtained from the above process. There is no availability of an Automated Scum removal machine.

An Anti-disturbance Control Algorithm for Permanent Magnet AC Servo System

Permanent magnet AC servo system is widely used in aerospace, industrial robots, petrochemical equipment and so on. In order to improve the anti-interference control performance of the permanent magnet AC servo system, in this paper, a non-singular terminal sliding mode controller based on the extended state observer is designed for the permanent magnet synchronous motor control system using the resolver as the angle sensor. The proposed algorithm uses the extended state observer to observe disturbance while realizing demodulation, and then uses the non-singular terminal sliding mode controller to realize high-precision anti-interference speed control. The proportion of the symbol term in the sliding mode controller can be reduced by compensating the disturbance observation term, thereby effectively suppressing the sliding mode chattering and improving the anti-interference performance of the system. Simulation results show that the proposed method has better control performance than the traditional PID control method in both steady-state accuracy and dynamic performance.

Dizajnirajte jeftinu delta robotsku ruku za aplikacije za odabir i postavljanje na osnovu kompjuterskog vida

In this paper, we develop a low-cost delta robot arm for grasping objects of unspecified size thanks to a vision system. Stepper motors are used instead of ac servo motors to build a low-cost delta robot arm. Furthermore, we use available materials and machining methods such as laser cutting and 3d printing instead of CNC milling and turning to reduce fabrication costs. The controller is based on a low-cost embedded controller - Arduino Uno for controlling the robot's motion. The vision system is constructed to determine the 3D coordinate of objects in the workspace as well as the sizes of objects. The gripper is opened with a distance of two fingers equal to the size of the objects, and the robot is controlled to the objects' coordinates to grasp them. An application to pick up objects on a conveyor belt is developed to validate the design. The experimental results show that the robot system works correctly, the robot arm moves smoothly, and the information determined by the vision system has a small error, ensuring that the robot can accurately pick up products.

Fault detection for Takagi–Sugeno fuzzy systems using multiple observers and ellipsoidal analysis

AbstractThis paper proposes a novel fault detection method for Takagi–Sugeno fuzzy systems via multiple observer design and ellipsoidal analysis. By considering only one fault distribution matrix at a time, the original system is divided into a limited number of fault modes. For each fault mode, an observer with finite‐frequency fault sensitivity performance and full‐frequency unknown inputs robustness performance is designed to generate the residual signal. Based on the designed observer, the ellipsoidal analysis is used to evaluate a residual and to give a fault detection index for each mode. In addition, the fault detection result is provided by combining “or” logical operation of the multiple indices. Numerical simulations and an AC servo motor experimental platform are used to verify the viability and validity of the proposed method.

Design of a Drum Brake Turnover Machine

In order to meet the demand of turning over brakes in an automatic assembly line of drum brakes, a drum brake turnover machine is designed. SolidWorks software is used to complete the three-dimensional modeling of the mechanical structure of the whole device; The control system of the drum brake turnover machine based on Schneider M241 PLC is designed, and the AC servo system control based on CANopen BUS is realized. The precise control of the position of reclaiming, overturning, discharging and turning angle of the drum brake is achieved. The engineering application results show that the equipment has a high degree of automation, stable operation, and good economy.

Research and Realization of Servo Control System Based on Medical Centrifuge

The power of the medical centrifuge is provided by the permanent magnet synchronous motor, so the AC control system of the permanent magnet synchronous motor directly determines the overall performance of the centrifuge. In this paper, the permanent magnet synchronous motor is the controlled object, the DSP28335 is used as the main control chip, and combined with the vector control strategy, the permanent magnet synchronous motor AC servo control system is designed. Finally, according to the design scheme, the soft and hard design of the motor control system is completed, and the system test is carried out. The test results show that the designed servo control system has fast response, good tracking performance, and stable operation, and has a certain market application prospect.

Dynamic and vibration characteristics of flexible robot manipulator under complex electromechanical coupling

Aiming at the complex electromechanical coupling effect at the joints of RP (rotating parallel) flexible robot, the electromechanical coupling dynamics and vibration response characteristics driven by AC servo motor, as well as the dynamic starting characteristics of the motor are studied. The physical model including electromagnetic and mechanical system coupling is established, and the dynamic model of the whole system is derived based on the overall electromechanical coupling effect and Lagrange Maxwell equation. With the help of Matlab/Simulink, a virtual simulation platform is built to analyze the output speed characteristics of the motor drive end and the motion of the moving base. Finally, through the joint simulation of Matlab/Simulink dynamic simulation model and Adams/controls virtual prototype model, the vibration characteristics of flexible manipulator under electromechanical coupling are obtained. The simulation results show that the electromechanical coupling effect of the motor drive end has a significant impact on the dynamic characteristics of the flexible manipulator. The conclusions obtained are of great value for improving the chiral energy of flexible machinery.

Radiation Principle and Spatial Direct Modulation Method of a Low Frequency Antenna Based on Rotating Permanent Magnet

The theory of mechanical antenna is still in its infancy at present, and its radiation mechanism, field distribution, modulation methods and other basic theories need to be explored and improved. The radiation mechanism of a rotating-magnet based mechanical antenna (RMBMA) is explored. An equivalent radiation model of the mechanical antenna is established. The field formula of mechanical antenna is derived using this model and rotation matrix. The spatial direct modulation method of mechanical antenna is also investigated. Two prototype antennas are fabricated using DC/AC servo motors and NdFeB magnets, and experiments are carried out to verify the correctness of the derivation and analysis. The measured and simulated results are in consistent with each other. By precisely controlling the moving parameters of an AC servo motor, signal of binary amplitude shift keying (BASK) is generated, and the original code sequence is recovered by demodulation.

Development of fast steerable launcher for ECRH system

Electron cyclotron resonance heating (ECRH) launcher is an electro-mechanical system mainly consisting of mirrors (flat and profiled), a steering mechanism, a vacuum barrier window and a UHV (Ultra High Vacuum) compatible gate valve which focuses and steers the ECRH beam into plasma. Presently, Steady-state Superconducting Tokamak (SST)-1 ECRH system has a 42 GHz Gyrotron capable of delivering 500 kW of RF power for the maximum duration of 500 ms. A new steerable ECRH launcher has been developed which can steer the EC beam along both poloidal and toroidal directions. The span of mirror movement in poloidal and toroidal directions is ±20° and ±50°, respectively. The poloidal motion of the mirror can be done in real-time during plasma operation and the mirror can be rotated by 20° in 100 ms. Two AC servo motors independently control the mirror movements through an assembly of motion feedthroughs, spur gears and mechanical linkages. The accuracy, repeatability and speed of both the motions have been measured under UHV in a specially designed vacuum chamber.

Friction-free approach for a servo system: Design of a robust sliding-mode control based on a recurrent fuzzy neural network

Uncertainties such as disturbance and nonlinear friction always exist in physical motion control systems and degrade the precision of their tracking performance. In this research, a practical control strategy is integrated with a continuously differentiable friction model for a high-performance AC servo motor that performs with a continuous control input and is, hence, more properly suited for industrial applications. To further lessen the external disturbance and improve the tracking accuracy, a recurrent fuzzy neural network scheme was developed to approximate the system uncertainties, and its stability was guaranteed by the design of robust laws. The proposed controller was implemented on a high-performance digital signal processor (TMS320C6727). The results of the tracking simulations and experiments show that the proposed control scheme has a feasible and effective design for engineering servo system. In comparison with other algorithms, our approach has smaller values for both the peak and the root mean square of the tracking error while maintaining friction compensation, and it can potentially have a software implementation.

High-Speed Control of AC Servo Motor Using High-Performance RBF Neural Network Terminal Sliding Mode Observer and Single Current Reconstructed Technique

This paper proposes a phase current reconstruction strategy based on a dc bus using a single current sensor for a surface permanent magnet synchronous motor (SPMSM). The method of a single current sensor reduces the number of mechanical hall sensors and shunt resistors by using a modified current reconstruction algorithm. The information of rotor position is estimated by the sliding mode observer for its rapid response and strong anti-interference ability, and the observer needs to detect voltage and current components from α − β coordinate system. In order to reduce the buffeting problem of sliding mode observers, an adaptive neural network is introduced, by the way of extracting angle speed estimated values from sliding mode observers, and these values are trained to obtain the compensate angular velocity and minus index value to suppress speed value. The performance of this sensorless speed regulation strategy in the high-speed region using a single current sensor with an optimized adaptive neural network is verified and evaluated by PSIM simulation and experiments.

Analysis of Power Quality issues of different types of household applications

Most of the loads used in our day-to-day life are non-linear in nature. To investigate the performance of various non-linear loads, a laboratory setup on different load combinations such as light, fan and drive system in this work. The unbalance in supply voltages, supply current and frequency, reduction in power factor and total harmonic distortion for current and voltages are monitored through this lab setup and also the results obtained from these systems are discussed in this paper. To check the nature of voltage, current, reactive power and power factor in real-time systems, a turret punch machine incorporated with several single-phase AC servo motors is considered. The variations in the parameters are recorded using the fluke analyzer. Finally, it is observed that current harmonics at the source side are dominant in both the laboratory setup and the real-time system. Next, shunt active power filters are applied to mitigate the current harmonics. The simulation for the system with compensations is conducted in the Matlab platform and the hardware implementation validates the same.

Fuzzy Wavelet Neural Network with the Improved Levenberg–Marquardt Algorithm for the AC Servo System

In this study, a fuzzy wavelet neural network with the improved Levenberg–Marquardt algorithm (FWNN-LM) is proposed to conquer nonlinearity and uncertain disturbance problems in the AC servo system. First of all, use the particle swarm optimization algorithm based on Levenberg–Marquardt (LM) to optimize parameters in the FWNN controller. Second, the potentiality of fuzzy rules (PFR) method is developed to optimize the structure of the FWNN by error reduction ratio (ERR). Furthermore, stability of FWNN-LM is proved by the Lyapunov method. Finally, simulation and prototype test results show that this method can improve the accuracy and robustness of the system in presence of load disturbances and parameter perturbations.

The Isometric And Eccentric Grip Strength In Athletes And Controls.

PURPOSE: To compare the characteristics of eccentric grip strength among athletes, elite climbers, and normal healthy subjects. METHODS: A total of 17 male subjects, including 8 athletes (age, 23.3 ± 3.1 years; height, 173.7 ± 3.6 cm; weight 71.4 ± 5.6 kg), 3 elite climbers (age, 19.3 ± 1.2 years; height, 162.8 ± 4.3 cm; weight 58.3 ± 3.1 kg), and 6male healthy control subjects (age, 26.0 ± 5.8 years; height, 172.3 ± 3.3 cm; weight, 64.0 ± 7.0 kg), participated in this study. They performed two maximal voluntary contraction tests (i.e., isometric [ISO], and eccentric [ECC] contraction) using a handgrip dynamometer (Takei, Co., Ltd, Tokyo, Japan) and original device utilized an AC servo motor (60 W class) to generate eccentric force at a constant speed of 32.67 mm/s. These tests were performed using the right hand. The values were calculated relative to body mass. RESULTS: ECC grip strength relative to body mass in athletes was higher than that in control subjects (p = 0.02, 1.15 ± 0.2 kg vs. 0.90 ± 0.2 kg). In particular, elite climbers showed higher ECC grip strength compared to athletes and control subjects (1.35 ± 0.1 kg, 1.08 ± 0.1 kg, and 0.88 ± 0.2 kg, respectively). There was no significant difference in ISO grip strength between athletes and control subjects. However, ISO grip strength relative to body mass in climbers was higher than those in athletes and control subjects (0.82 ± 0.1 kg, 0.69 ± 0.1 kg, and 0.67 ± 0.1 kg, respectively). The effect sizes of ECC and ISO grip strength relative to body mass between athletes and control subjects were 1.5 and 0.5, respectively. CONCLUSIONS: Our results suggest that eccentric grip strength might be more effectively manifested in athletes rather than isometric grip strength, especially in climbers.

Path Tracking of Permanent Magnet Synchronous Motor Using Fractional Order Fuzzy PID Controller

Permanent magnet synchronous motor (PMSM) AC servo system has the characteristics of uncertainty, time-varying, nonlinear and fractional order. Applying the traditional control method is difficult to achieve the desired control effect. The fuzzy control has strong adaptability to the parameter change, nonlinearity and imprecise model of the controlled object. The simulation model of permanent magnet synchronous motor three closed-loop systems is established. The control principle and the realization of space vector pulse width modulation (SVPWM) are studied by using a vector control strategy. Due to the fractional-order characteristic of the motor, a fuzzy logic algorithm is used to realize the parameter self-tuning of the fractional-order proportional integral differential (PID) controller. The controller is selected as the position regulator of the servo motor. It combines the precision of fractional-order PID controller with the adaptability of fuzzy control and adds feed-forward to improve the response speed. The path tracking experiments on several different paths are carried out, and the results show that the control method is effective and can meet the trajectory tracking requirements of servo control. Finally, the speed and position tracking test of the PMSM AC servo system is carried out on the test verification platform, which verifies the effectiveness of the control algorithm.

Improving the Tracking Performance under Nonlinear Time-Varying Constraints in Motion Control Applications: From Theoretical Servo Model to Experimental Validation

In the high-accuracy control of an AC machine, the knowledge of pure system parameters, with no deviation in drive coefficients and no disturbance or other nonlinear components, is a difficult issue for operators, even though it is occasionally nonviable. To overcome these troubles, this paper introduces a robust adaptation strategy based on pseudo fuzzy logic and sliding mode control (PFSMC) for an AC servo drive subject to uncertainties and/or external disturbance. Owing to the robustness of the SMC technique, the reduced sensitivity to uncertainties, and the enhanced resistance to disturbances from the pseudo fuzzy mechanism, this control algorithm can guarantee not only system stability but also the improvement of tracking errors in the steady state. To validate the design efficiency of PFSMC, both simulation and laboratory tests of the proposed scheme and a conventional PID scheme were performed to compare them as follows. In a computer environment, test cases with and without certainties were implemented with two controllers to visualize the comparative responses. Then, the two control methods were integrated into a real-world hardware platform to acquire practical outcomes. From these results, it can be noted that our successful approach showed a feasible, effective, and robust performance in AC drive.

Research on servo motor motion control system based on Beckhoff PLC

In order to meet the requirements of high precision, reliability and real-time control of biaxial motion.Taking Beckhoff PLC CX9020 and Yaskawa Σ - 7S series AC servo controller as the control core, using Yaskawa SGM7J series motor and servo driver matching, the X-Y double axis servo motion control system is designed, and the overall hardware design of the control system is carried out. This paper focuses on the parameter setting, analog and digital acquisition, programming and HMI interface setting of servo motor control system. The debugging operation shows that the system runs stably and meets the control requirements of accurate positioning.

Hardware design of PMSM control system based on DSP

Compared with traditional motor, permanent magnet synchronous motor has the characteristics of strong anti-interference ability, high starting torque and power density, and good speed regulation performance.Permanent magnet synchronous motor servo system has become a research hotspot in the field of servo drive.In this paper, with DSP28335 as the main control chip to give a permanent magnet synchronous motor AC servo control hardware system design scheme, the paper introduces in detail the system core control circuit, main power circuit, detection circuit design and the choice of main components.The hardware system designed has been applied to engineering practice, and has achieved good control effect.