Micrometric Movements Research Articles

Analysis of the Movements in Relation to the Degrees of Freedom in Precision Honing

Honing is a precise machining process with high standards for the resulting form, dimension and surface quality. Additionally, tolerances can even be further reduced by honing processes. Essential for the adherence of high quality is the coaxial interaction of the honing tool and the workpiece. This presented work investigates the fundamental kinematic and dynamic process during the internal long-stroke honing process. The focus of the investigation is the honing gimbal, which realizes the displacement and tilting compensation movements. Based on a substituted mechanical system, mathematical differential equation system was prepared in order to characterize the four degrees of freedom of the honing gimbal in relation to the honing tool. The next section describes the experimental setup, which allows to determine these micrometer movements, followed by the measurement results. The results cover the displacement compensation movements by the modification of the rotation speed from 50 min-1 to 2500 min-1.

Parametric Structural Schemes of Piezoactuators for Nano-and Micrometric Movements at a Longitudinal Piezoeffect

Solutions to the wave equation and structural-parametric models of piezoactuators at a longitudinal piezoeffect were obtained. Effects of the geometric and physical parameters of the piezoactuators and external load on its static and dynamic characteristics were determined. The parametric structural schemes for piezoactuators for nano- and micrometric movements at a longitudinal pie-zoeffect were obtained. The transfer functions were determined. The parametric structural schemes and the transfer functions of the piezoactuators were obtained for calculation of the automatic control systems for nano- and micrometric movements with piezoac-tuators at a longitudinal piezoeffect. The static and dynamic characteristics of the piezoactuators were determined. Application of the piezoactuators solves the problems of precise matching in microelectronics and nanotechnology, compensation for the temperature and gravitational deformations, atmospheric turbulence by a wave front correction. By solving the wave equation with allowance for the corresponding equations of the piezoelectric effect, the boundary conditions on the loaded working surfaces of a piezoactuator, the strains along the coordinate axes, it is possible to construct a structural parametric model of a piezoactuator. The transfer functions and the parametric structural schemes of the piezoelectric actuator were obtained from the equations describing the corresponding structural parametric models of the piezoactuators for nano- and micrometric movements at a longitudinal piezoeffect.

Transcription Kinetics Heterogeneity of Highly Mobile Identical Genes Revealed by Simultaneous Measurement at the Single Cell Level

2560-Plat Transcription Kinetics Heterogeneity of Highly Mobile Identical Genes Revealed by Simultaneous Measurement at the Single Cell Level Enrico Gratton, Paolo Annibale. Biomedical Engineering, University of California, Irvine, Irvine, CA, USA. Fluorescence microscopy was used in combination with molecular constructs to measure in real time and in living cells the transcriptional activity of individ- ual genes and their displacement within the nucleus. The question whether local mobility of individual chromatin regions is correlated to their transcriptional output is still the subject of active research. There is a consensus that the local chromatin environment and physical accessibility may play a role in modu- lating transcription, possibly determining the large heterogeneity observed in RNA Polymerase II (PolII) elongation rates measured from fluorescence as- says. Employing high-speed fluorescence nanoimaging we measure here at ms-temporal resolution PolII elongation and we are able to resolve the minute displacements of identical active genes surrounding a labeled transgene array. We observe a correlation between the transcriptional activity and sub- micrometer movements of the active genes that is evidence of an active molec- ular mechanism determining displacements of the active genes following transcriptional bursts. Furthermore, we detect a significant heterogeneity in the kinetics of identical genes measured simultaneously and at sub-second tem- poral resolution within the same cell. Together these observations rule out cell to cell variability as the underlying cause for the observed kinetic heterogeneity and point to the local chromatin environment and physical accessibility as the source of PolII elongation variability. Work supported in part by NIH P41- GM103540 and NIH P50-GM076516

Mechanical and control characteristics of multilayered piezodrives of nano- and micrometric movements for parallel and coded control

Mechanical and control characteristics of a multilayered piezodrive of nano- and micrometric movements are obtained in the case of parallel and coded control. Static and dynamic characteristics of simple and multilayered piezodrives of nano- and micrometric movements for longitudinal and transverse piezoelectric effects are determined.

Correcting devices of control systems for deformation of multilayered piezodrives of nano- and micrometric movements

Transfer functions of multilayered piezodrives of nano- and micrometric movements are obtained for longitudinal and transverse piezoelectric effect, piezodrive characteristics are corrected using built-in piezo sensor. Correcting devices are chosen for providing high quality of control systems for deformation of multilayered piezodrives and required index of oscillation. Absolute stability conditions of control systems for deformation of multilayered piezodrives of nano- and micrometric movements for longitudinal and transverse piezoelectric effect are determined.

Static and dynamic characteristics of multilayered electromagnetoelastic transducer of nano- and micrometric movements

A generalized structural-parametric model of a multilayered electromagnetoelastic transducer is constructed; the influence of geometric and physical parameters of the transducer and external load on its static and dynamic characteristics is determined; transfer functions of the multilayered electromagnetoelastic transducer of nano- and micrometric movements are obtained.

10.1007/s11488-008-1014-y

Absolute stability conditions for the control system of deformation of an electromagnetoelastic converter for nano- and micrometric movements under deterministic and random impacts are obtained.

Hysteresis characteristics of piezotransducer for nano- and micrometric movements and their harmonic linearization

Hysteresis characteristics of a piezotransducer for nano- and micrometric movements are studied; experimental and theoretical hysteresis characteristics with main and partial loops are presented. Transfer function of the nonlinear part with the hysteresis characteristic in the form of the main hysteresis loop for piezotransducer deformation is obtained. The coefficients of harmonic linearization of the hysteresis characteristic of the piezotransducer are determined.

Investigation of static and dynamic characteristics of a piezomotor for nano-and micrometric movements

Static and dynamic characteristics of a piezomotor of nano-and micrometric movements for nanotechnology and microelectronics equipment are calculated, the parametric structural diagram of the piezomotor is constructed, and the influence of physical and geometric parameters of the piezomotor on the static and dynamic characteristics is determined.

Absolute stability conditions for the control system of deformation of an electromagnetoelastic converter for nano- and micrometric movements

Absolute stability conditions for the control system of deformation of an electromagnetoelastic converter for nano- and micrometric movements under deterministic and random impacts are obtained.

Generalized structural-parametric model of electromagnetoelastic converter for control systems of nano- and micrometric movements: V. Multidimensional scheme

On the basis of solution of the wave equation and taking into account deformations over coordinate axes, the multidimensional structural-parametric model and the parametric structural diagram of the electromagnetoelastic converter in the form of a piezodrive of nanomotions are constructed. The influence of geometric and physical parameters of the piezodrive and the external load on its static and dynamical characteristics and transfer functions is determined. The parametric structural diagrams of multicoordinate piezo converters are obtained.

Generalized structural-parametric model of an electromagnetoelastic converter for control systems of nano-and micrometric movements: IV. Investigation and calculation of characteristics of step-piezodrive of nano-and micrometric movements

The characteristics of the compound pawl and the compound central piezo converter of the step piezodrive are considered. The influence of the geometric and physical parameters of the compound piezo converter and the external load on its static and dynamical characteristics is determined. The transfer functions of the piezo converter as an electromechanical system with distributed or lumped parameters are obtained. The static and dynamical characteristics of the step piezodrive are studied.

A generalized structural-parametric model of an electromagnetoelastic converter for nano-and micrometric movement control systems: III. Transformation of parametric structural circuits of an electromagnetoelastic converter for nano-and micrometric movement control systems

Based on the solution of a wave equation, a structural-parametric model of electromagnetoelastic converter for the electromechanical drive of nano-and micrometric movements was constructed. A transformation was conducted for the structural-parametric model and the parametric structural circuits. The influence of the geometric and physical parameters of this converter and of the external load on the static and dynamical characteristics was estimated.

Design and control of a mobile micromanipulator driven by ultrasonic motors with multidegrees of freedom

A miniature mobile micromanipulator system for performing submillimeter grasping and manipulation tasks has been designed and tested. The system consists of a two-fingered gripper attached to a 5 d.o.f. robot micromanipulator. Features of the system include: (i) the structure of the mobile micromanipulator is composed of high-precision ultrasonic actuators with several degrees of freedom (d.o.f.) (this makes the robot system easy to integrate and allows it to perform directed and precise translation motion or rotation in a plane or in space); (ii) the electronic drivers, based on a bidimensional PWM control architecture, allows us to command the multidirectional manipulator movement accurately, and, through them, to control the position and orientation of the gripper; and (iii) the gripper is actuated by a shape memory alloy actuator and employs strain gage sensors to perform the gripping force control. The prototype version of this mobile micromanipulator can perform micrometer movements with speeds in the range of few mm/s to several 10-1 m/s and manipulates objects in the size range of 2-0.5 mm. The design of the micromanipulator affords plenty of scope for further miniaturization. With the recent increased interest that has been shown in micro-robotics, the prototype robot system described in this paper could, with further development and miniaturization, form part of a micro-robot assembly system.

Calibration of a Siemens Elmiskop 1b double tilting goniometer stage

The calibration of a double tilting stage, comprising two concentric gimbal rings with orthogonal axes, is described. An empirical analytical expression is used to relate the observed angular tilts and drive micrometer movements. The angular tilts were estimated from the displacement of a Kikuchi pattern produced by a single crystal platelet of ZnS. The calibration parameters are presented using graphical methods which facilitate ready reference during the operation of the microscope. Taking into account the complexity of the movement, the method of calibration is less time consuming than other methods which have been described. Adequate accuracy is achieved for obtaining approximate orientation relationships between phases.

Electronic micrometer system for precise recording of coordinates from ultracentrifuge plates

The reading of position coordinates from ultracentrifuge schlieren and interference plates is greatly facilitated by the use of a zero-backlash transducer that can be attached to a standard microcomparator stage. On command from the operator, an electronic system controls the operation of a Flexowriter which prints and punches paper tape records of micrometer positions to the nearest 1 μ for all points selected throughout the full range of micrometer movements. The combination of human control with automatic recording of digital data by a mechanically simple system is believed to utilize the capabilities of man and machine to best advantage in performing the measuring tasks of an ultracentrifuge laboratory.