L. Canan Dulger

A study on a hybrid actuator

Abstract Classically, constant speed motors drive some mechanical transmissions such as gears, cams and linkages in order to produce non-uniform motion in machines. Such machines may allow a limited flexibility, by changing dimensions of the components. To answer the need for flexibility constant speed motors are replaced by servomotors. Besides other disadvantages, the cost of this solution is often very high especially for large capacity machines. Hybrid machines, which are a combination of two types of motors and mechanisms, have flexibility at a reduced cost. A new hybrid actuator is proposed in the study presented here.

Mathematical modelling, simulation and experimental verification of a scara robot

Abstract A complete mathematical model of SCARA robot (Serpent 1) is developed including servo actuator dynamics and presented together with dynamic simulation in this paper. The equations of motion are derived by using Lagrangian mechanics. Dc servo motors driving each robot joint is studied with PD controller action. Serpent 1 robot is instructed to achieve pick and place operations of three different size cylindirical objects through assigned holes. The performance of robot-actuator-control system is examined with numerical simulation and experimentally verified. The results of experimentation are given with comments. An agreement between the model and the experiments is certainly obtained herein.

Signature verification (SV) toolbox: Application of PSO-NN

Analysis of signature is a widely used and developed area of research for personal verification. A typical signature verification (SV) system generally consists of four components: data acquisition, pre-processing, feature extraction and verification. A reliable SV toolbox, based on the verification of off-line signatures is developed with the proposed algorithm. The technique is based on a neural network (NN) approach trained with particle swarm optimization (PSO) algorithm. To test the performance of the proposed PSO-NN algorithm two types of forgeries-unskilled and skilled-are examined. The experimental results are illustrated on the selected signature databases and presented herein.

Mechanisms, classifications, and applications of servo presses: A review with comparisons

Servo presses have recently come into prominence for sheet metal forming operations due to their flexibility, controllability, and simplicity. Minimum energy consumption and maximum tool life are their significant characteristics, leading to considerable reductions in manufacturing costs. This article presents technological review on design and applications of servo presses. The characteristics of servo presses are described and compared to conventional and hydraulic presses. Mechanisms used in servo presses and their motion concepts are evaluated with design features. The industrial background of mechanisms is reported with typical examples from leading press manufacturers. A new classification of the servo presses is presented according to mechanisms and drivers. Besides, ranking of press types according to power control and mechanisms is determined. Servo presses with slider-crank mechanism design are preferred due to their distinctive characteristics.

Motion control and implementation for an AC servomotor system

This paper presents a study on trajectory tracking problem for an AC synchronous servomotor. A mathematical model for the system including AC synchronous servomotor, gearbox, and a load is developed to examine the systems dynamic behavior. The system is controlled by a traditional PID (proportional + integral + derivative) controller. The required values for the controller settings are found experimentally. Different motion profiles are designed, and trapezoidal ones are implemented. Thus, the experimental validation of the model is achieved using the experimental setup. The simulation and experimental results are presented. The tracking performance of an AC servomotor system is illustrated with proposed PID controller.

CONTROL OF A SCARA ROBOT: PSO-PID APPROACH

This paper presents an approach where the Particle swarm optimization (PSO) is employed to get optimum PID controller parameters to control of a SCARA robot. PSO is an evolutionary technique which is originated from swarm intelligence. A practical application of the PSO-PID controller is performed with the system dynamics. A simulation study is also included with the proposed controller by using the systems dynamic equations with the actuator dynamics and optimum PID parameters. Different trajectories are studied. Performances of the traditional controllers; PD, PID and the application of PSO-PID controller are then compared. Simulation results are presented. The numerical results definitely enforced the potential use of PSO-PID controller herein.

Robotic arm dynamic and simulation with Virtual Reality Model (VRM)

This paper presents a study on control and simulation of the robotic arm system. A dynamic model is designed, and a Virtual Reality Model (VRM) is built for the robot. A kinematic model is represented for the robot links and joints. A simulation module is built by using SIMULINK/SimMechanics and by estimation of motor-gear transfer function. A PID control system (Proportional-Integral-Derivative) is then applied. The virtual model is created by Simulink 3D Animation. OWI-535 robotic arm is an articulated manipulator robot, it was chosen as testing system. The robot was developed with an interface control system. The interface control system is built to perform closed-loop control. Different trajectories were implemented on the robot. The results were shown for the simulated system and real robot in designing accuracy and system control response. Robot followed the desired trajectories efficiently.

A New Artificial Neural Network Approach in Solving Inverse Kinematics of Robotic Arm (Denso VP6242).

This paper presents a novel inverse kinematics solution for robotic arm based on artificial neural network (ANN) architecture. The motion of robotic arm is controlled by the kinematics of ANN. A new artificial neural network approach for inverse kinematics is proposed. The novelty of the proposed ANN is the inclusion of the feedback of current joint angles configuration of robotic arm as well as the desired position and orientation in the input pattern of neural network, while the traditional ANN has only the desired position and orientation of the end effector in the input pattern of neural network. In this paper, a six DOF Denso robotic arm with a gripper is controlled by ANN. The comprehensive experimental results proved the applicability and the efficiency of the proposed approach in robotic motion control. The inclusion of current configuration of joint angles in ANN significantly increased the accuracy of ANN estimation of the joint angles output. The new controller design has advantages over the existing techniques for minimizing the position error in unconventional tasks and increasing the accuracy of ANN in estimation of robots joint angles.

Off-line Signature Verification (SV) using the Chi-square statistics

Off-line Signature Verification (SV) is performed using Particle Swarm Optimisation Neural Network (PSO NN) algorithm. The technique is based on NN approach trained with PSO algorithm. The presented verification system includes image-processing techniques and other mathematical tools in its structure. To test the performance of the proposed algorithm, three types of forgeries, namely random, unskilled and skilled, are examined. A database with 1350 skilled and genuine signatures taken from 25 volunteers is used for testing the algorithm. The experimental results are presented with comparisons on verification accuracy and statistical figures.

An automation system for data processing and motion generation

A user friendly automation system is developed and integrated with a servo press control system for position data processing and generation. Providing connection between controller and driver, the new motion generation that has capability of industrial motion produce for different strokes is designed. Three feed-forward input parameters; position, velocity and acceleration data are applied for enhancing the control precision. Performances of servo press are evaluated by looking at system responses with the ram motion. The press main parameters are taken as the stroke length and the number of strokes produced. It is possible to change ram kinematics by changing drawing speeds, stroke rates or introducing dwell. Experimental studies are applied with the manufactured prototype. Experimental results are indicated that the press driven by PMSM with cascade feed-forward (CasFF) control has shown high tracking performance. Flexibility in ram motions is certainly introduced with higher tonnage ratings performing higher strokes herein.