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Dynamic analysis of an a-shaped piezo-actuated walking microrobot
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010, Vancouver, BC ; Volume 10 , 2010 , Pages 161-170 ; 9780791844472 (ISBN) ; Vossoughi, G ; Sharif University of Technology
2010
Abstract
In this paper, a novel, A-shaped microrobot with nanometric resolution for precision positioning applications is addressed. The locomotion concept of the mechanism is founded on the "friction drive principle". To achieve the translational motion, a stack piezoelectric actuates the microrobot near its natural frequency. The dynamic modeling of the mechanism is based on the assumptions of linear behavior of piezo stack actuator and Coulomb friction model at contact points. The suitability of three simple, friction-based locomotion modes for implementation on the proposed device is presented. Influences of different friction coefficients on the behavior of the microrobot, with respect to...
Sliding Contact Problem of a Round Wedge with a FGM Coated Substrate
, M.Sc. Thesis Sharif University of Technology ; Adibnazari, Saeed (Supervisor)
Abstract
In this research, sliding contact problem of a rounded apex wedge with a FG coated substrate is investigated. The structure includes two components. The first is the FG coating and then, the homogeneous substrate which is connected to the FG coating. Usually, it is considered that the homogeneous substrate is a metal and properties at the connection are metallic. Then, properties varies gradually through the thickness of the FG coating, so, the material at the surface of the structure is a ceramic. It is assumed that, properties varies exponentially and continuously through the FG coating and the poisson’s ratio is constant. Beside, it is supposed that the conditions of coulomb friction...
Locomotion modes of a novel piezo-driven microrobot: Analytical modeling and performance evaluation
, Article Mechanism and Machine Theory ; Volume 52 , 2012 , Pages 248-266 ; 0094114X (ISSN) ; Vossoughi, G. R ; Sharif University of Technology
2012
Abstract
This paper presents a novel, sliding, A-shaped microrobot with nanometric resolution for precision positioning applications. The microrobot is actuated near its natural frequency using a piezoelectric stack actuator to produce translational motion. The dynamic modeling of the mechanism is based on the assumptions of the linear piezoelectric behavior and the Coulomb friction model. Using this model the required condition for generating net motion is found. The suitability of three simple, friction-based locomotion modes for implementation on the proposed device is addressed. Influences of some important configuration parameters on the behavior of the microrobot, based on defined criteria, are...
Robust velocity control for an A-shaped micro-robot with stick-slip locomotion
, Article Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science ; Volume 230, Issue 14 , 2016 , Pages 2413-2426 ; 09544062 (ISSN) ; Vossoughi, G. R ; Sharif University of Technology
SAGE Publications Ltd
Abstract
In this paper, the problem of velocity control of a micro-robot's locomotion with nanometric resolution has been investigated. A sliding, A-shaped micro-robot, used in precision positioning applications is analyzed. This micro-robot is actuated by means of a piezoelectric stack actuator in order to produce translational and periodic motion. A dynamic model of the robot is proposed assuming linear behavior for the piezoelectric stack and Coulomb friction model. Then, in order to control the velocity of micro-robot, first a robust sliding mode control is used so that the relative angle between the legs in the micro-robot tracks a periodic reference signal. The velocity tracking for the...
Modeling and Control of Atomic Force Microscope Based Nanoparticle Manipulation
, M.Sc. Thesis Sharif University of Technology ; Meghdari, Ali (Supervisor)
Abstract
In the recent years, there has been great interest in exploring methods for assembly and manipulation at the micro/nanoscale to build miniaturized systems, devices, structures, and machines. This thesis aims at two-dimensional manipulation of nanoparticle using Atomic Force Microscope (AFM) probe. The nanoprobe is used to push the spherical micro/nanoparticle. Continuum based modeling and simulation of the manipulation task is presented. The proposed nanomanipulation model consists of all effective phenomena in nanoscale. Nanoscale interaction forces, elastic deformation in contact areas, and friction forces in tip/nanoparticle/substrate system are considered. The utilized friction models...