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In this paper, we describe the development of an orthogonal microrobot for accurate microscopic operations. To conduct the
microscopic operation, a simple locomotion mechanism composed of one piezoelectric actuator and two U-shaped electromagnets
is proposed. The orthogonal microrobot can move precisely in one-axis with the manner of an inchworm. W...
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... microrobots to study industrial applications where such precise microrobots provide effective benefits [12][13][14][15]. Over the last several years, we have developed versatile microrobots for micro- scopic manipulations [16]. We have also developed flexible micromanipulation organized by three versatile microrobots under microscopes as shown in Fig. 1 [17]. Here, a spherical micromanipulator is used as a microscopic manipulator. In experiments, we have demonstrated precise and flexible handling of a miniscule pipe under the good collaboration of these small robots. This manipulation device has 11 DOF with less than 100 nm resolution. We confirmed the efficiency of the microrobots. ...
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... Figure 9 is the experimental results. B 0 is the magnetic flux density when no voltage is applied. We notice that the amount of the change of magnetic flux density is proportional to the applied voltage. We also notice that the sum of right and left magnetic flux densities is constant. The approximate model of the magnetic force is explained in Fig. 10. Here, B represents the magnetic flux density and S U-shaped electromagnet Stacked type piezoelectric actuator represents the cross-section area of the magnetic core. F is the magnetic force between the magnetic core and the metal surface. In this model, we can describe approximately the magnetic force ...
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... 8 represents that the sum of magnetic force increases when electromagnets is applied a voltage. That is why the electromagnet which is applied no voltage moves although the other electromagnet which is applied a voltage is fixed. The motion sequence of this one-axis robot is depicted in Fig. 11. This simple one-axis microrobot moves like an inchworm with less than 100 nm resolution. We can make two-axial orthogonal microrobots if we connect the micro- robot to another microrobot orthogonally as Fig. 12. In this figure, the bottom robot moves itself to the X direction and the upper robot moves its steel base to the Y ...
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... moves although the other electromagnet which is applied a voltage is fixed. The motion sequence of this one-axis robot is depicted in Fig. 11. This simple one-axis microrobot moves like an inchworm with less than 100 nm resolution. We can make two-axial orthogonal microrobots if we connect the micro- robot to another microrobot orthogonally as Fig. 12. In this figure, the bottom robot moves itself to the X direction and the upper robot moves its steel base to the Y direction. We can easily set up these orthogonal microrobots in a narrow working space such as a table of an inverted microscope because the size of this robot is very small, i.e. 58 mm in length, 58 mm in width and 37 mm ...
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... can easily set up these orthogonal microrobots in a narrow working space such as a table of an inverted microscope because the size of this robot is very small, i.e. 58 mm in length, 58 mm in width and 37 mm in height. Figure 13 shows the experimental setup for measuring the displacements. We measure the robot's motion by capaci- tance sensors whose resolution is 30 nm. ...
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... the output noise is about 60 nm so the measuring resolution is 60 nm in experiments. Figure 14 is the experimental results of the relationship between the displacement and the number of steps at various frequencies. The robot moves up to 300 Hz and the step width is about 1.6 to 3.3 μm when 100 V is applied to the piezoelectric actuator. ...
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... width less than 0.1 μm can also be controlled if we control the applied voltage of the piezoelectric actuator. The robot can move with a 200 g payload. Generally, a piezoelectric actuator has a hysteretic non-linearity as depicted in Fig. 15. A distance d bp is a difference between a displacement at minimum voltage and a displacement at maximum voltage. A distance d h is a width of a hysteretic loop. The distance d h itself does not influence a repeatability of the step width directly because the orthogonal robot moves with an inchworm manner. We assume that a wire ...
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... have developed a micropump driven by the piezoelectric actuator as shown in Fig. 16. The sequence of this micro- pump is very simple. The piezoelectric actuator pushes and pulls the liquid inside the silicon tube as depicted in Fig. 17. Table 3 shows the typical performance of the micropump. This tiny pump is so small and light that the orthogonal microrobot can carry. In several experiments, we have checked this tiny ...
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... have developed a micropump driven by the piezoelectric actuator as shown in Fig. 16. The sequence of this micro- pump is very simple. The piezoelectric actuator pushes and pulls the liquid inside the silicon tube as depicted in Fig. 17. Table 3 shows the typical performance of the micropump. This tiny pump is so small and light that the orthogonal microrobot can carry. In several experiments, we have checked this tiny pump pushes 50±0.5 nl when the inner diameter of the glass pipette is 15 μm and input voltage to the piezoelectric actuator is 30 ...
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... micropump can hold an egg cell with a diameter of 100 μm by decreasing the input voltage of piezoelectric actuator. However, we could not control the discharge rate a Depending on the length of v-groove Fig. 16 Structure of the micropump of the pump when the inner diameter of injection pipette is smaller than 10 μm. Generally, inner diameter of the injection pipette should be less than a few micrometers at the artificial insemination and nuclear cell transfer. We plan to improve the sensitivity of this small ...
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... attach small manual stages to two-axial microrobots for positioning pipettes and a dish in Z direction as shown in Fig. 18. We positioned pipettes and the dish in focal height by manual Z stage in experiments. Fig. 19 is the photograph of the experimental set up and the working area for a cell processing organized by the three two-axial orthogonal microrobots on an inverted microscope. We put the holding pipette on the left robot for sample capturing. We ...
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... attach small manual stages to two-axial microrobots for positioning pipettes and a dish in Z direction as shown in Fig. 18. We positioned pipettes and the dish in focal height by manual Z stage in experiments. Fig. 19 is the photograph of the experimental set up and the working area for a cell processing organized by the three two-axial orthogonal microrobots on an inverted microscope. We put the holding pipette on the left robot for sample capturing. We also put the injection pipette on the right robot. Between these robots, we arrange another ...
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... succeeded in holding an egg cell with a diameter of 100 μm and sticking the pipette with a diameter of 5 μm into the egg cell under the good collaboration of the joystick and foot pedals' manual control and the visual feedback's automatic control. Figure 21 is the microscopic image of typical experimental operations. We believe that this manipulation device has much potential for actual use in various kinds of micromanipulation, such as an artificial insemination and a positioning of microparts of portable devices. ...
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