Nowadays, with the growing use of atomic force microscope (AFM) nanorobots in the fabrication of nanostructures, research in this area has proliferated. A major limiting factor in the utilization of AFM nanorobots is the lack of real-time monitoring. Computer simulations have been widely used to improve the feasibility of nanoparticles pushing by means of the AFM-based nanorobots. In order to prevent damage to a cantilever during the nanoparticle displacement, it is necessary to come up with an algorithm that can check the feasibility of the manipulation operation with regards to the geometrical constraints of the cantilever and the considered path. The existing models for predicting the feasibility of manipulation processes are limited to 2D manipulation models (spherical nanoparticles), which are incapable of predicting the feasibility of 3D operations (lack of a comprehensive model of 3D cases). In this paper, to predict the feasibility of displacing cylindrical nanoparticles and to consider the path of motion (rough surface), a model has been proposed that can ensure the feasibility of the manipulation operation in advance. Finite element simulation has been employed to obtain the maximum load that can be withstood by a cantilever of a specific geometry. Also, the effect of surface roughness on the critical manipulation force has been explored. Ultimately, an algorithm has been presented for determining the feasibility of the manipulation operation by considering the particle motion path and the cantilever geometry.

In this paper, the process of pushing rough cylindrical micro/nanoparticles on a surface with an atomic force microscope (AFM) probe is investigated. For this purpose, the mechanics of contact involving adhesion are studied first. Then, a method is presented for estimating the real area of contact between a rough cylindrical particle (whose surface roughness is described by the Rumpf and Rabinovich models) and a smooth surface. A dynamic model is then obtained for the pushing of rough cylindrical particles on a surface with an AFM probe. Afterwards, the process is simulated for different particle sizes and various roughness dimensions. Finally, by reducing the length of the cylindrical particle, the simulation condition is brought closer to the manipulation condition of a smooth spherical particle on a rough substrate, and the simulation results of the two cases are compared. Based on the simulation results, the critical force and time of manipulation diminish for rough particles relative to smooth ones. Reduction in the aspect ratio at a constant cross-section radius and the radius of asperities (height of asperities based on the Rabinovich model) results in an increase in critical force and time of manipulation.

Due to the growing use of Atomic Force Microscope (AFM) nanorobots in the moving and manipulation of cylindrical nanoparticles (carbon nanotubes and nanowires) and the fact that these processes cannot be simultaneously observed, a computer simulation of the involved forces for the purpose of predicting the outcome of the process becomes highly important. So far, no dynamic 3D model that shows changes in these forces in the course of process implementation has been presented. An algorithm is used in this paper to show in 3D, the manner by which the dynamic forces vary in the mentioned process. The presented model can simulate the forces exerted on the probe tip during the manipulation process in three directions. Because of the nonlinearity of the presented dynamic model, the effective parameters have been also studied. To evaluate the results, the parameters of the 3D case (cylindrical model) are gradually reduced and it is transformed into a 2D model (disk model); and we can observe a good agreement between the results of the two simulations. Next, the simulation results are compared with the experimental results, indicating changes in lateral force. With the help of the offered dynamic model, the cantilever deformation and the forces interacting between probe tip and particle can be determined from the moment the probe tip contacts the nanoparticle to when the nanoparticle dislodges from the substrate surface.

Since their invention, nanomanipulation systems in scanning electron microscopes (SEMs) have provided researchers with an increasing ability to interact with objects at the nanoscale. However, most nanomanipulators that are capable of generating nanometer displacement operate in an open-loop without suitable feedback mechanisms. In this article, a robust and effective tracking framework for visual servoing applications is presented inside an SEM to achieve more precise tracking manipulation and measurement. A subpixel template matching tracking algorithm based on contour models in the SEM has been developed to improve the tracking accuracy. A feed-forward controller is integrated into the control system to improve the response time. Experimental results demonstrate that a subpixel tracking accuracy is realized. Furthermore, the robustness against clutter can be achieved even in a challenging tracking environment.

Piezoelectric nanoactuators, which can provide extremely stable and reproducible positioning, are rapidly becoming the dominant means for position control in transmission electron microscopy. Here we present a second-generation miniature goniometric nanomanipulation system, which is fully piezo-actuated with ultrafine step size for translation and rotation, programmable, and can be fitted inside a hollowed standard specimen holder for a transmission electron microscope (TEM). The movement range of this miniaturized drive is composed of seven degrees of freedom: three fine translational movements (X, Y, and Z axes), three coarse translational movements along all three axes, and one rotational movement around the X-axis with an integrated angular sensor providing absolute rotation feedback. The new piezoelectric system independently operates as a goniometer inside the TEM goniometer. In situ experiments, such as tomographic tilt without missing wedge and differential tilt between two specimens, are demonstrated.

A novel 3-DOF prismatic-revolute-cylindrical (PRC) translational compliant parallel micromanipulator (CPM) has been designed for 3-D nanomanipulation in this paper. The system is configured by a proper selection of hardware and analyzed via the established pseudo-rigid-body (PRB) model. The CPM workspace is determined taking into account the physical constraints imposed by piezoelectric actuators and flexure hinges.