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Nanorobotic strategy for nondestructive mechanical characterization of carbon nanotubes

Micro and Nanosystems 2010年第1期2卷 32-37页

作者： Eichhorn, V. Bartenwerfer, M. Fatikow, S. Division Microrobotics and Control Engineering University of Oldenburg 26111 Oldenburg Germany

The characterization of individual nanoscale objects such as carbon nanotubes (CNTs) is one of the main challenges in material science and nanotechnology. In this paper, we present a nanorobotic strategy allowing the nondestructive mechanical characterization of individual CNTs. A nanorobotic setup is developed to perform elastic deformations of multiwalled carbon nanotubes (MWCNTs). Characteristic force/displacement curves are measured and used to calculate the Young's modulus. Transmission electron microscope (TEM) images of the given CNTs show an additional conical layer of amorphous carbon enclosing the real multiwalled structure. Thus, different theoretical models are examined aiming to find the proper mechanical description of the analyzed CNTs. The experimental results show a significant influence of the outer carbon layer on the whole mechanical behavior of the MWCNTs. © 2010 Bentham Science Publishers Ltd.

关键词： Elastic moduli

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Real-time object tracking for the robot-based nanohandling in a scanning electron microscope

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Journal of Micromechatronics 2006年第3期3卷 267-284页

作者： Sievers, Torsten Fatikow, Sergej Division Microrobotics and Control Engineering University of Oldenburg D-26111 Oldenburg Germany

In this paper, current research work on an automated nanohandling station using mobile microrobots is presented. For the automated positioning of mobile microrobots a closed-loop control system is necessary, usually using data from pose sensors for the degrees of freedom (DOF) of the microrobot are needed. Mobile microrobots with piezo slip-stick actuation mostly do not have internal pose sensors to determine a global pose. This paper focuses on the continuous pose estimation (tracking) of mobile microrobots by external visual sensors. One possibility for fast pose estimation is the application of video cameras in combination with image processing algorithms as global sensors. However, for pose estimation with accuracy in the nanometer range high-resolution sensors are necessary. In consideration of resolution, image acquisition time and depth of focus a scanning electron microscope (SEM) is a powerful sensor for high-resolution pose estimation of a microrobot. On the other hand, the use of a SEM requires high demands on the image processing. High update rates of the pose data for the robot control require a short image acquisition time of the SEM images. As a result, the image noise increases as frame averaging or averaging of the detector signal is time consuming. This paper presents two approaches to tracking a micro-object in a SEM image stream. First, a cross-correlation algorithm is described, which enables pose estimation (x, y, Ψ) in extremely noised images in real-time. Afterwards object tracking with active contours is presented. This approach allows real-time tracking with more than 3 DOF by using shape spaces, instead of defining large model sets as it is necessary for correlation-based pattern matching. © VSP 2006.

关键词： Nanotechnology

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Towards Automated Robot-Based Nanohandling

Towards Automated Robot-Based Nanohandling

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2009中国控制与决策会议

作者： Fatikow S. Wortmann T. Mikczinski M. Dahmen C. Stolle C. Division Microrobotics and Control Engineering(AMiR) University of OldenburgGermany

ISBN: (纸本)9781424427239

One of the key challenges of microsystem- and nanotechnologies is the automation of robot-based nanomanipulation. However,there is limited sensor feedback due to lack of appropriate *** feedback is required for repeatable actuator movements from macro- down to the *** complicates the design of reliable automation *** this paper,the development of an automated robot-based toolbox for cell injection and handling is presented. This toolbox includes several sensor methods,bridging several orders of magnitude as feedback for automation. A non-linear support vector machine(SVM) is applied for classification of the viability of cells as feedback for quality control.A visual servoing algorithm for position tracking of the injection needle as well as an injection force sensor have been *** automation results and the control system are explained.

关键词： Nanohandling cell classification visual servoing force-sensing distributed control architecture

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Image processing architecture for real-time micro- and nanohandling applications

Image processing architecture for real-time micro- and nanoh...

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11th IAPR Conference on Machine Vision Applications, MVA 2009

作者： Wortmann, Tim Dahmen, Christian Tunnell, Robert Fatikow, Sergej Division Microrobotics and Control Engineering University of Oldenburg Germany

ISBN: (纸本)9784901122092

This article presents a software architecture for image processing applications. Its intended use is in the automation of manipulation processes at the microand nanoscale. The main requirements for this architecture are the capability for real-time processing, the flexibility to cover a wide range of different applications and simplicity of usage. Some of the biggest challenges include online changes of control- and data-flow, integration of a large number of devices for microscopy and the need for high-speed result forwarding. The architecture has been implemented and tested extensively. Three key applications are presented: object tracking, classification of biological cells and 3D image reconstruction for scanning electron microscopes.

关键词： Application programs

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Enhanced low harmonic waveform for low-bandwidth inertia-drive actuator 17

Enhanced low harmonic waveform for low-bandwidth inertia-dri...

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17th International Conference and Exhibition on New Actuator Systems and Applications, ACTUATOR 2021

作者： Wei, Junyang Fatikow, Sergej Division Microrobotics and Control Engineering University Oldenburg Germany

ISBN: (纸本)9783800754564

Inertia-drive is one category of drive principles that is widely used for piezoelectric actuators, thanks to its simple control and drive structure. However, such principle suffers from the residual vibrations caused by its saw-tooth waveform, leading to a limitation of the actuation performance. In this paper, an optimized driving waveform that named enhanced low harmonic waveform, is proposed to tackle with the deadband issue of low-bandwidth inertia-drive actuator when actuated with Low Harmonic Waveform. The waveform is composed of a basic low-harmonic waveform and a friction reduction vibration waveform. The dynamic model of the drive is established and the performance comparisons are made between simulations and experiments. The effectiveness of the enhanced low harmonic waveform is verified. © VDE VERLAG GMBH · Berlin · Offenbach.

关键词： Harmonic analysis

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Fast and robust position determination in the scanning electron microscope

Fast and robust position determination in the scanning elect...

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2013 Australasian Conference on Robotics and Automation, ACRA 2013

作者： Dahmen, Christian Tiemerding, Tobias Division of Microrobotics and Control Engineering University of Oldenburg Germany

ISBN: (纸本)9780980740448

This paper deals with the extraction of small object positions in the scanning electron microscope (SEM). An approach based on line scanning and new object tracking approaches are presented and evaluated for their capabilities to reliably track objects in the SEM when the objects are moving quickly. Image acquisition of such fast moving objects has the issue of strong distortions and very high displacements, which can affect the performance of the algorithms. The new approaches are compared to common image processing algorithms.

关键词： Scanning

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Hardness determination of EBiD-layers containing tungsten and cobalt

Hardness determination of EBiD-layers containing tungsten an...

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3rd International Conference on Computational Methods and Experiments in Material Characterisation 2007

作者： Wich, T. Luttermann, T. Mircea, I. Division Microrobotics and Control Engineering University of Oldenburg Germany

ISBN: (纸本)9781845640804

Electron Beam induced Deposition (EBiD) is a promising process technology for nano-structuring and -prototyping inside a scanning electron microscope (SEM). Firstly, the EBiD-process used for layer deposition is described. We have performed nanoindentation experiments on EBiD-layers with the purpose of determining their hardness. A special setup for nanoindentation inside the SEM is described. Before performing tests on EBiD-layers, calibration measurements on fused silica and sapphire were necessary. Hardness of the silicon wafer substrate and of the EBiD-layers has been also determined. The layers were small quadrates, with dimensions in the range of 20 20 m, with a thickness varying between 93 and 2256 nm. Nanoindentation tests on the deposited layers revealed values between 7.1 and 10.0 GPa for tungsten containing deposits and between 3.4 and 3.5 for cobalt containing deposits depending on the metal-content.

关键词： Deposition

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Carbon nanotube detection by scanning electron microscopy

Carbon nanotube detection by scanning electron microscopy

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11th IAPR Conference on Machine Vision Applications, MVA 2009

作者： Wortmann, Tim Fatikow, Sergej Division Microrobotics and Control Engineering University of Oldenburg Germany

ISBN: (纸本)9784901122092

This study describes an approach towards the detection of carbon nanotubes in scanning electron microscopic images. It is designed to work in a real-time environment for automated nanofabrication. Main difficulties are the high level of image noise and the occurrence of debris objects. A descriptor derived from the principle component analysis of the geometrical object distribution is found to be a very helpful indicator for object classification. It turns out to be largely invariant to alterations in imaging conditions. All methods described have been implemented and evaluated in largescale experiments. The procedure has also been fully integrated into a distributed control architecture.

关键词： Carbon nanotubes

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Hardware-software co-design tracking system for predictable high-speed mobile microrobot position control

Hardware-software co-design tracking system for predictable ...

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5th IFAC Symposium on Mechatronic Systems, MECHATRONICS 2010

作者： Diederichs, Claas Division Microrobotics and Control Engineering Oldenburg University Oldenburg Germany

ISBN: (纸本)9783902661760

Fast closed-loop control is a key issue for high-throughput automated micro-and nanohandling. Currently, mobile robot position control relies on computer vision using FireWire- or USB-cameras. This approach has several drawbacks for closed-loop control, such as limited update rate, high latency and unpredictable jitter. To overcome these drawbacks, a new hardware-based position tracking algorithm is presented and compared to current position control sensors. Additionally, several measurements of a closed-loop controlled mobile robot for micro- and nanohandling show the system's advanced performance in terms of speed and accuracy using the new sensor. © 2010 IFAC.

关键词： Field programmable gate arrays (FPGA)

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Development of a force microsensor for robot-based nanohandling 9th

Development of a force microsensor for robot-based nanohandl...

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9th IFAC Symposium on Robot control, SYROCO 2009

作者： Luttermann, T. Mikczinski, M. Wich, T. Fatikow, S. Division Microrobotics and Control Engineering University of Oldenburg Oldenburg Germany

ISBN: (纸本)9781617825583

The process of electron beam induced deposition was used to create sensor structures for strain measurements with outer dimensions of 20 μm by 30 μm. The sensor principle was derived from classic macroscopic strain gage sensors. Therefore, electrically conductive lines with a width of 200 nm were directly deposited on an SiO2 coated silicon wafer by writing them with the electron beam of a scanning electron microscope and in the presence of an organometallic tungsten precursor. To determine the properties of the sensor structure, the electric noise was measured and compared to a constantan strain gage and a semiconductor strain gage. From this noise voltage, the best achievable mechanical resolution for every strain gage type is determined. The electric resistance of the sensor structure was measured at defined strain and compression to determine the gauge factor which is needed to calculate the value of arbitrary strain from measured resistances. Long time period measurements of the electrical resistance showed effects of a burning-in process, aging and wear of the sensor structure, which were analyzed in the last part of this work.

关键词： Strain gages

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