Johannes Quellmalz

Influence analysis on the model comparison performance index for servo drive control

The paper deals with the proposed performance index of [1], which can assess command action performance of a servo drive in terms of the parameterization of the comparison model. By reversing a tuning rule, the comparison model can be parameterized without any a priori knowledge, with the drawback of low significance for some controller detuning directions. The performance index is examined further regarding practical online usage as in a running production process here. Signal sampling is considered in terms of sample time and quantization. Excitation independence as a basic goal for a performance index is also examined. For a more realistic picture the index is calculated with the monitored system operated under cascaded position control. The influence of position command signal sequences with different jerk and acceleration parameters are analyzed. In conclusion the limitations of the performance index are discussed and required future work is discussed.

Improved Controller Performance for Electromechanical Axes

The cascaded position control structure is state of the art in modern production machines and machine tools. Since an adequate controller performance of the electromechanical axes is still a key aspect for a resource efficient and high-quality production, this topic is addressed by the paper. An overall approach/framework to monitor and ensure an improved controller performance over time, comprising five tangible approaches is presented. All methodologies were developed in the department for control and feedback control technologies of the Technische Universitaet Chemnitz. They will be demonstrated and also be discussed based on experimental results.

A Model Comparison Performance Index for Servo Drive Control

This paper describes an approach for monitoring closed loop speed control of electromechanical drives. The data of the closed loop is evaluated and concentrated to a performance index, giving a scalar value to measure setpoint change behavior. The method uses an order-reduced model as comparison basis to closed-loop signals, which is possible to implement on controller equipment. Parameterization of the comparison model is addressed even pointing out a provision without requiring a-priori knowledge. Influence of the main parameters is shown by means of simulation results. Following, experiments are carried out and compared to theoretical results. In conclusion usability and possible further improvement is discussed.

Optimierung des Energiebedarfs der CNC-gesteuerten Bearbeitung

Kurzfassung Der Energieverbrauch bei der spanenden Herstellung eines Werkstücks wird von einer Vielzahl von Größen beeinflusst. Der vorliegende Beitrag greift die Bereiche Prozessplanung, Regelungs- und Stelltechnik sowie Konfiguration der CNC-Steuerung und Anpassung des NC-Programms heraus. Mittels virtueller Prototypen und geeigneter Simulationen kann bereits im Vorfeld der realen Fertigung eine energetische Bewertung des geplanten Bearbeitungsprozesses erfolgen und das NC-Programm optimiert werden.

Comparison of Feed Drives with a Process Oriented Design Methodology

The paper points out a novel design methodology for electromechanical linear axis. It is based on common process parameters and an automated iterative solution algorithm. For the first time ever, different types of electromechanical linear axes can be compared. Furthermore, an optimum solution aiming a low moment of inertia ratio is the result of the design process. Using the example of a machining center, simulation and experimental results are shown. The performance of the process-oriented design methodology relating to additional design objectives is shown in this context.

Performance Index for Servo Drives under PI Speed Control

The paper points out a minimum variance based performance index for restricted controller structure, known in literature and applied in process industries. The theory is introduced briefly. As core of the paper adaption to the topic of speed control for electromechanical drives is shown. Simulational and experimental results for various single and dual-mass systems show good sensitivity to relevant parameters. As main drawback, the index prefers tough controller settings.

Control Structures for Opposed Driving, Coupled Linear Drives

In manufacturing linear motors are mainly used in the field of lightweight and highly dynamic drives. The high acceleration forces leads to vibration excitations of the machine structure that causes production inaccuracies. This can be improved by coupling two corporate acting and opposed driving linear drives in one drive train. The coupled structure can improve the static and dynamic properties by distributing the forces between both drives. In order to guarantee the requirement for high accuracy in synchronous tracking, control structures and controller tuning methods are going to be discussed based on simulation and experimental results.