Daiki Kamiya

Palmtop Pantograph Mechanism with Large-deflective Hinges for Miniature Surface Mount Systems

In the present paper, a new surface mount system with parallel arrangement miniature manipulators is proposed for use in system downsizing. The miniature manipulator consists of a molded palmtop pantograph mechanism, which is composed of large deflective hinges and links, both made of the same materials. In order to create such systems, first, durability of the pantograph mechanism has been confirmed by fatigue tests. Next, the input and output displacement characteristics of the pantograph mechanism have been experimentally discussed. Finally, propriety of the proposed system has been confirmed.

Large-Deflection Spiral-Shaped Micromirror Actuator

We present a new two-axis spiral-shaped micromirror manipulator developed for free-space optical switching. The actuator is an electrostatic actuator, which is composed of two different parts that are fabricated using conventional surface-micromachining processes and are then assembled. Instead of conventional monolithic self-assembling design approaches, these two parts are fabricated on two different chips and assembled using a spatial-mechanical approach. The design utilizes the increased flexibility of the spiral-shaped electrode and the zipping-effect technique in order to increase the maximum rotation angle. The footprint of the assembled device is 600 mum times 600 mum, and the height of the micropyramid is 200 mum. The switch is simulated using an energy method and a coupled electromechanical model. Its performance is measured statically using a reflection measurement approach. A continuous rotational actuation of 17deg has been achieved with an actuation voltage of 235 V.

Durability of Large-Deflective Hinges made of Blend Polypropylene used for Molded Pantograph Mechanisms

A molded pantograph mechanism consisted of large-deflective hinges and links is used in a new surface mount system proposed by Horie, et al.(2000). To obtain long life, large-deflective hinges, we showed the method to conduct the repetitive tensile-compressive and bending test on a hinge specimen, and manufactured experimental equipment for a fatigue test. We also evaluated the test equipment and confirmed its effectiveness. The materials of the large-deflective hinge were selected as follows: (1) polypropylene (PP), (2) polymerization blend PP, (3) machine blend PP, and (4) another machine blend PP(+MAH-PP). The hinge specimen used for the fatigue test was made with the injection molding machine. From the relationship between the number of cycles leading to the fracture of the hinge and the repetitive tensile-compressive loads in the fatigue test, it has been confirmed that the difference in hinge thickness and the difference in the materials greatly influenced the inner damage of the hinges.

Mathematical modeling and design of a novel 2-DOF micro attraction actuator for a micro optical switch

Many studies on optical switches have been performed in an attempt to develop optical information networks to speed information technology. In reality, however, mirror manipulators cannot be applied to multiple input and output systems due to both insufficient output displacements by the mirror parts inside the manipulator, and the difficulty of designing structures and mechanisms suitable for multi-dimensional manipulation. The principal reasons for insufficient displacement are the high rigidity of the elastic parts compared to the available driving forces and the pull-in effect. Therefore, in order to develop optical switches capable of multiple input and output switching, we suggest a novel 2-DOF(degree of freedom) electrostatic microactuator. The actuator is composed of one mirror with four beams laid about it in a corkscrew pattern, with four corkscrew electrodes on the substrate below and one mirror support pyramid situated under the mirror. Using electrostatic force, one or more of the beams are attracted from their outer ends toward the substrate. The mirror is then tilted by an angle proportional to the attracted length along the beam. The inclination and direction of the mirror are determined by the combined attracted length of the four beams. In this work we derive the mathematical model for the corkscrew beam microactuator for optical switches and show that this mathematical model accurately simulates the device by comparison with finite element analysis results. We use this mathematical model for design of the microactuator. Further we show that the designed optical switch microactuator is capable of rotating the mirror from +32 to -32 degrees about two axes with a maximum operating voltage of 163 volts. Finally, stress analysis of the actuator shows that the generated stress in the structure is at most 369 MPa.

New miniature pantograph mechanisms with large-deflective hinges for micro-bonding by adhesives

In this paper, a parallel arrangement of miniature size manipulators is proposed. This system can be used as a manipulator system for micro-bonding by adhesives or as surface mount systems for micro devices on a substrate in OA/AV aids, personal phones, etc. The miniature manipulator consists of a molded pantograph mechanism, which is composed of large deflective hinges and links with the same materials, i.e. polypropylene. First, the durability of the pantograph mechanism including one parallelogram is confirmed by a fatigue test. A pantograph mechanism with dimensions of hinge length 200 /spl mu/m, thickness 180 /spl mu/m, and width 5 mm was not destroyed for repeated input motion of more than one million times in the fatigue test. Next, the input and output displacement characteristics of the pantograph mechanism are experimentally discussed. The output point repeatability of the mechanism at a maximum /spl plusmn/11 /spl mu/m has been confirmed. Consequently, the feasibility of the proposed miniature pantograph mechanisms for a micro device adhesion system or a surface mount system has been shown by discussion related to the total working time compared to the traditional surface mount system. Moreover, in order to obtain a constant output link orientation, a new pantograph mechanism including three parallelograms is proposed. In the new mechanism, we confirmed that the maximum orientation angle error between vertical direction and output link moving direction is 1.61/spl times/10/sup -2/ degrees for pick working, and 1.29/spl times/10/sup -2/ degrees for place working.

3-DOF Planar Positioning-Orientation Mechanisms with Links and Large-Deflective Hinges

One of the author has already proposed and developed the molding pantograph mechanism with large-deflective hinges and links for miniature surface mount system for manufacturing system. The characteristic of the pantograph mechanism is investigated theoretically and experimentally. The aimed final miniature manufacturing system for micro assembling is composed of the pantograph mechanisms and the following positioning-orientation mechanism. In this paper, a new molding 3-DOF(Degrees of freedom) planar positioning-and-orientation mechanism with large-deflective hinges and links is proposed. The mechanism has two function: a transmission function between manufacturing stations and a positioning-orientation function at the manufacturing station. The mechanism with six large-deflective hinges and seven links is made by the small molding injection machine. The used material is PP (Polypropylene). The mechanism has three linear actuators. In the experiments, the singular points of the mechanism is investigated in its working space and compared with the theoretical results. The performance concerning the transmissibility of the proposed new molding 3-DOF planar positioning-orientation mechanism is confirmed.

Development of miniature pantograph mechanisms with large deflective hinges for new surface mount systems

In this paper, a new surface mount system with parallel arrangement miniature manipulators is proposed for use in system downsizing. The miniature manipulator consists of a molded pantograph mechanism, which is composed of large deflective hinges and links, both made of the same materials. In order to create such systems, first, durability of the pantograph mechanism is to be confirmed by fatigue tests. Next, the input and output displacement characteristics of the pantograph mechanism are to be experimentally discussed. Finally, propriety of the proposed system should be confirmed.

Characteristic analysis of basic mechanisms with large deflective elastic hinges for three-dimensional micromechanisms

In this paper, a basic mechanism of 3D micromechanisms is proposed by making use of number synthesis of mechanisms. The output point of the proposed mechanism can move in the vertical direction when two linear input points move in the inverse horizontal direction, and can move horizontal direction when two linear input points move in the same horizontal direction. The validity and the characteristics of the proposed mechanism are investigated theoretically and experimentally by using a polyethylene macromodel manufactured by a small modeling injection machine. Finally, an example of a micromechanism manufactured by semiconductor fine-machining technique is shown.

Optimum Design of Mass Distribution of the Injection Molding Pantograph Mechanism with Constant Output Link Orientation

In this paper, an optimum design of an injection molding pantograph mechanism is discussed. This mechanism will be used to the miniature surface mount system in one room factory. First, a reduction of force acting at hinge caused by the movement of the mechanism is discussed. And the injection molding pantograph mechanism is synthesized based on the result of a numeric calculation of the algorithm. Moreover, the force acting at hinge of this mechanism is analyzed, and the algorithm that reduces force acting at hinge by changing the shape and dimension of links considering the influence of the movement of the mechanism is proposed. In addition, the shape and dimension of links to which force acting at hinge of this mechanism is reduced from the result of a numeric calculation of this algorithm is designed.

Displacement analysis of micromirror composed of large deflection spiral beams

We present a new two-axis spiral-shaped micromirror manipulator developed for free space optical switching. The actuator is an electrostatic actuator, comprised of two different parts, which are fabricated using conventional surface micromachining processes and then assembled. In spite of the conventional monolithic self-assembling design approaches, these two parts are fabricated on two different chips and assembled using a spatial-mechanical approach from point of view of a simple MEMS-manufacturing process of each part. Making as one MEMS device becomes a lot of number of processes. Because a fixed place of the screw beam from the mirror device is at the position where only the height of a lower micro pyramid is low compared with the height of a central point. The design utilizes the increased flexibility of the spiral shaped electrode and zipping effect technique in order to increase the maximum tilt angle. The footprint of the assembled device is 600µm×600µm and height of the micro pyramid is 200µm.The switch was simulated using an energy concept and electromechanical coupled model. Its performance was measured statically using a reflection measurement approach. A continuous tilt actuation of 17 degree has been achieved with actuation voltage of 235 volts.