Karoly Santa

A Neural Approach for the Control of Piezoelectric Micromanipulation Robots

Micromanipulation has become an issue of primary importance in industry and biomedicine, since human manual capabilities are restricted to certain tolerances. The manipulation of biological cells or the assembly of a complete microsystem composed of different microcomponents are examples of the application of piezoelectric-driven microrobots. An automated microrobot-based micromanipulation desktop-station is developed by an interdisciplinary group at the University of Karlsruhe. The process of assembly takes place in the field of view of a light optical microscope. This paper focuses on motion control problems of the microrobots. The ability of an intelligent microsystem to adapt itself to the process requirements is of great importance, especially for assembly robots. The microrobots must be able to operate in a partially defined environment and to ensure reasonable behaviour in unpredicted situations. A neural control concept based on a reference model approach is proposed as a solution. It is shown, that the neural controller is able to learn the desired behaviour. It considerably outperforms an analytically designed linear controller. This is demonstrated both in simulation and in the real environment.

Control of microassembly-robots by using fuzzy logic and neural networks

Abstract An automated micromanipulation desktop-station that has been developed at the University of Karlsruhe includes several piezoelectric microrobots capable of moving over long distances and manipulating in the range of a few nanometers. In this paper, the control problems of the microrobots and the sensoric problems in the micromanipulation station are discussed. The ability of an intelligent microsystem to adapt itself to the process requirements is, especially for assembly robots, very important. The microrobots should be able to operate in a partially defined environment and to guarantee a reasonable behavior in unpredicted situations. For this, the control methods are needed, which do not require an exact system model and which allow a reasonable compromise between the real-time information processing and the amount of input data; they must also make definite decisions based on vague or incomplete information. Two promising methods are fuzzy control and control by a neural network. The paper presents some approaches to improve the robot behaviour by using these advanced control methods.

Sensor system and powerful computer system for controlling a microrobot-based micromanipulation station

Mobile microrobots, which are capable of performing microscopic motions, have become a subject of great interest all over the world. They have the potential to be used for a variety of applications: in industry for assembly of microsystems or for the testing of silicon chips; in medicine for handling biological cells, etc. A new model of an automated micromanipulation station, which includes piezoelectric microrobots is now being built by an interdisciplinary research group at the University of Karlsruhe, Germany. This paper describes a sensor system and a powerful tailorable computer for controlling the micromanipulation station.

Control system for motion control of a piezoelectric micromanipulation robot

Abstraet-Micromanipulation by microrobots has become an issue of primary importance in industry and biomedicine, since human manual capabilities are restricted to certain tolerances. The manipulation of biological cells or the assembly of a microsystem composed of several microcomponents are good examples. An automated microrobot-based micromanipulation desktop station has been developed at the University of Karlsruhe. The process of assembly takes place in the field of view of a light optical microscope. This paper focuses on motion control problems of the piezo-driven microrobots employed by the station. The ability to adapt itself to the process requirements is of great importance for micromanipulation robots. They must be able to operate in a partially defined environment and to ensure reasonable behavior in unpredicted situations. A neural control concept based on a reference model is proposed as a solution. It is shown that the neural controller is able to learn the desired behavior. It considerably...

Flexible piezoelectric micromanipulation robots for a microassembly desktop station

The design of a microassembly desktop station is a major challenge for microsystem technology. This paper presents several piezoelectric micromanipulation robots, which have been developed to be used in a microassembly station. These robots are of different design and use different actuation principles so that each robot serves for a specific task. They are capable of travelling over long distances and of manipulating in the range of a few nanometers. Several robots of this kind can be accommodated in a microassembly station and can cooperate and perform microassembly tasks as a team. They can also be used for other operations such as online testing of microelectronic chips or manipulating biological cells.

Development of a neural controller for motion control of a piezoelectric three-legged micromanipulation robot

Micromanipulation by microrobots has become an issue of primary importance in industry and biomedicine, since human manual capabilities are restricted to certain tolerances. The manipulation of biological cells or the assembly of a microsystem composed of several microcomponents are good examples. An automated microrobot-based micromanipulation desktop station has been developed at the University of Karlsruhe. The process of assembly takes place in the field of view of a light optical microscope. This paper focuses on motion control problems of the piezo-driven microrobots employed by the station. The ability to adapt itself to the process requirements is of great importance for micromanipulation robots. They must be able to operate in a partially defined environment and to ensure reasonable behaviour in unpredicted situations. A neural control concept based on a reference model is proposed as a solution. It is shown, that the neural controller is able to learn the desired behaviour. It considerably outperforms an analytically designed linear controller in the real environment.

Positioning Fault Detection of a Piezoelectric-Driven Microrobot

Abstract Micromanipulation has become an issue of primary importance in industry and biomedicine, the manual capabilities being restricted to certain tolerances. For example manipulation of biological cells or an assembly of a whole microsystem composed of different microcomponcnts have to be carried out by piezo electrically-driven miciorobots. For this reason, an automated microrobot-based micromanipulation station is developed by an interdisciplinary group at the University of Karlsruhe. The process of assembly takes place in the field of view of a light optical microscope. The principal sensors of the S3rstem are CCD cameras. One of them, coupled with the microscope, is the local sensor that allows the automation of the manipulation process under the microscope. A second one, the global sensor, supervises the entire system. In this work we present the first step of a method for the detection of faults occurring during the manipulation process. This first stage consists of detecting and processing a position deviation of the microrobot.

Information Processing in a Flexible Robot-Based Microassembly Station

Abstract In biology, microelectronics and microsystem technology many operations are today performed by hand which might also be done by micromanipulation robots. Several prototypes of such robots have already been built and tested, and now higher-level problems have to be tackled: control systems with adequate computational power, user-interfaces and planning systems for micromanipulation systems have to be implemented and tested. Special attention must be paid to the requirements of micromanipulation, which differs greatly in some aspects from conventional manipulation. This paper discusses the information processing aspects of the control system of a micromanipulation station. The micromanipulation station consists of a microassembly robot working under a light-optical microscope, a CCD camera and an XY-stage. The requirements for the control computer system are high: assembly and execution planning has to be done in order to perform fully-automated microassembly, a vision system is necessary, and the control of the microrobots and the peripherals connected to the system demand high I/O power. The paper also shows a user interface to access the system resources in a user-friendly way and presents a sketch of the planning and the control algorithms

Intelligente Ansteuerung von atuonomen Mikrorobotern in einer Mikromanipulationsstation

Zur Handhabung von Objekten, deren Abmessungen im μm- oder sogar im nm-Bereich liegen, wurde an der Universitat Karlsruhe am Institut fur Prozesrechentechnik und Robotik eine Mikromanipulationsstation entwickelt. Das Herzstuck dieser Station ist ein vielseitig einsetzbarer mit piezoelektrischen Elementen steuerbarer Mikromanipulationsroboter, der wartungsfreundlich und kostengunstig ist. Der Roboter besitzt zwei Manipulatoren, mit denen er verschiedene Mikromanipulationsaufgaben durchfuhren kann. Mit Hilfe dieses Roboters ist auch eine automatische Montage von Mikrosystemen denkbar. In diesem Beitrag werden verschiedene regelungstechnische Ansatze fur die Ansteuerung von verschiedenen Mikromanipulationsrobotern in einer Mikromanipulationsstation vorgestellt.