Papers by Keyword: Micromanipulation

Abstract: The actual miniaturization trend, present in several industrial sectors, requires high performance capabilities in micromanipulation and assembly. A complete automation of these operations, by means of robots, could result in a significant cost cut in the final product. In this work we present the mechatronic design and optimization of a 3 d.o.f. Delta type PKM for micromanipulation. Starting from a reference task (pick and place with high stroke rate) the optimal links length has been determined by considering several kinematic performance indexes; afterwards the actual link sizing has been performed considering dynamic loading, also taking into account the effect of the links flexibility on end effector trajectory. A direct drive actuation has been chosen, where the motor sizing has been performed to satisfy several criteria: maximum and r.m.s. torque and maximum speed. The motor selection has been speeded up querying a database built by collecting data from the catalogues of several producer. Furthermore robot joints have been carefully designed in order to reduce backlash and friction.

Abstract: At present, sub-micro-Newton (sub-μN) micro-force in micro-assembly and micro-manipulation is not able to be measured reliably. The piezoelectric micro-force sensors offer a lot of advantages for MEMS applications such as low power dissipation, high sensitivity, and easily integrated with piezoelectric micro-actuators. In spite of many advantages above, the research efforts are relatively limited compared to piezoresistive micro-force sensors. In this paper, Sensitive component is polyvinylidene fluoride (PVDF) and the research object is micro-force sensor based on PVDF film. Moreover, the model of micro-force and sensor’s output voltage is built up, signal processing circuit is designed, and a novel calibration method of micro-force sensor is designed to reliably measure force in the range of sub-μN. The experimental results show the PVDF sensor is designed in this paper with sub-μN resolution.

Abstract: Orientation adjustment is an important issue in the micromanipulation of cells. A non-contact method based on a swirl for cell orientation control was introduced in this paper. The swirl is produced by a pair of opposite micro-fluids squirting from two parallel tubes. Cell orientation adjustment is realized by cells rotation due to swirl viscous drag, which drives cells to desired configurations. The appropriate distances between the end face of the two tubes and the distance between the axes of them are 1-3 times tube diameter for the cells rotating in the swirl central zone. Especially when the distances are kept double the cell diameter, cells rotate steadily round the swirl central point. By pulsating jetting, fluctuant micro-fluid are generated which make cell rotating a certain angle. Adjusting the pulse duration, pressure and jetting velocity, the cell rotation angle can be controlled which make orientation control more precisely. The method is valid for cells of different shapes and sizes. The effectiveness of the proposed non-contact method for cell configuration control was verified by experiments.

Abstract: Trapping and positioning of single cells has played a major role in various fields of bioengineering, such as cell screening, analysis, induction and pathologic diagnosis, etc. In this work, we report a new non-contact microfluidic-based method for single cells trapping and positioning. A pair of microtubes of same specification is symmetrically placed on opposite sides of the cell. When fluid flowing through microtubes squirts in the same velocity toward the cell, the cell will be immobilized and clamped due to symmetrical fluid pressure generated around it. Feasibility of the reported method is validated by experiments. This method is also capable of trapping and positioning micro particles.

Abstract: At present, reliable micro-force sensing is one of the most important research for micromanipulation and micro-assembly. Six kinds of methods to detect micro-force are described in this paper. Analysis of the basic principle and detection accuracy of each sensing method, and applications in micro-assembly and micromanipulation are briefly introduced. The purpose of this paper is to be useful to provide some references for scholars engaging in the micro-force sensing, which in turn promotes automatic processing level of micro-assembly and micromanipulation to reliably manufacture micro devices of high quality.

Abstract: Position and orientation adjustment is an important issue in the micromanipulation of cells. A non-contact method based on micro-fluid for cell position and orientation control was introduced in this paper. The cells were positional fixed by the pressure force of a pair of lined micro-fluids from two tiny tubes. The orientation adjustment was realized by rotating cells in swirls caused by a pair of parallel micro-fluids. By spraying fluctuant micro-fluid, cells orientation can be controlled more precisely. The experiments proved that this non-contact cell position and orientation adjustment method is feasible and secure.

Abstract: In this paper, an electromagnetic design method for a novel DC Lorentz Motor for micromanipulation is described. To optimize permanent magnet (PM) array and minimize the magnetic field coupling among PMs, the distribution of magnetic field and the fluctuation of Lorentz force are obtained by the 3D finite-element method (FEM). Through the electromagnetic analysis, an optimized distribution and shape of PMs are found. Finally, the optimized DC Lorentz motor is manufactured. These simulation results are verified by those of the experiment results, which presents the finite element model and simulation results are reasonable.

Abstract: This paper describes how the web technologies are utilized for a robot system synthesis. A web application is created for automation of the synthesis of closed structures for micro- and nano-applications, utilizing the advantages tense piezo-actuators and closed robot kinematical structures. The algorithm, integrated into the developed web based application, offers a synthesis of robot kinematic chains without extensive knowledge in this domain. The aim is to facilitate synthesis of such kind of kinematic chains from specialists who will generate optimal solutions for automation and robotisation of the requested micro- and nano-process.

Abstract: An ultra-precision instrument with concomitant micromanipulation techniques is designed and set up to measure the damage strength of a single biomimetic microcapsule. It can provide the capability of simultaneously measuring the applied force and resultant displacement of a single microcapsule, with maximum force range of 5mN, resolution of 0.1µN and ultimate traveling distance up to 12mm, resolution of 1nm, respectively. By armed high magnification side-view system, it can offer extra and withal valuable information for the supervened analyzing. The bursting force of urea-formaldehyde biomimetic microcapsules of diameter 65µm in glucose solution was measured by this technique. The microcapsule was burst when the deformation reached a value of 56.2% of its diameter and the corresponding resonant force is about 1700µN. The technique provides an effective means to characterize elastic properties of micro biomimetic capsules and compare mechanical strength of microcapsules made of different ingredients.