Silicon magnetic Hall sensor for high temperature applications has been developed with Silicon-On-Insulator(SOI) structure. The Hall cell of magnetic sensor is dielectrically isolated by silicon dioxide from silicon substrate in order to reduce leakage current between the Hall cell and silicon substrate at high temperature. The theoretical sensitivity of the magnetic sensor was calculated and compared to the experimental result. There is a tradeoff between sensitivity and available temperature range. The magnetic sensor has temperature offset drifts which are caused by size mismatching, unbalance of doping condition and thermal stress between sensor and package. These offsets are compensated by design optimization and signal conditioning circuit. As a result, silicon magnetic Hall sensor with SOI structure could be operated steadily over high temperature of 200°C.

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For the purpose of a highly precise position measurement of a tunneling machine, this paper presents simple models of a tunneling machine s motion including the effect of conduits. There are two modes in the tunneling machine s movement. First, a doublestep forward movement mode that is used to hard soil, is studied. Its model is derived from the force/moment equilibrium acting on the tunneling machine, assuming elastic deformation of the ground. Next, a single-step forward movement mode that is applied to soft soil, is analyzed and its model is obtained by applying the minimum energy theory to the ground strain assuming both elastic and plastic deformations of the ground. By comparing the calculated results with experimental results, the feasibility of the proposed models is confirmed. Finally, the position measurements of the tunneling machine using a rate-gyroscope and a gyrocomps are studied. The measuring errors caused by the translation motion of the tunneling machine and by the discrete measurement are estimated by using our model. The analysis shows that the position measurement with the gyrocomps is more precise than that of using the rate-gyroscope.

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We have fabricated a micro manipulator with 1mm in diameter and 80mm in length. This manipulator has 5 degrees of freedom and uses SMA (Shape memory alloy) plates as actuators. To eliminate the assembly process and reduce the number of parts, we have developed MIF (Multi-function Integrated Film). This is a thin flexible film, which includes all electrical components; heaters, sensors, cables and electrodes, required to the SMA manipulator. As the MIF is fabricated with technology of semiconductor manufacturing, it is possible to reduce the size easily. The structure of this manipulator is very simple, because all electrical components are integrated in the MIF and the SMA plates have two functions; actuator and structural component. Therefore, complex assembly techniques are not needed. Using the strain and temperature sensors in MIF, we realized feedback control for SMA plates. As a result, this manipulator achieved 1mm in position accuracy at the tip. In addition, we have developed the device, which includes CMOS electrical circuit in MIF monolithically. For this device, electrochemical etching is applied.

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We developed a micro tunneling unit, a device which can control the magnitude of a tunneling current that passes through a vacuum gap by adjusting the gap distance with a microactuator. Since the unit has a tunneling tip in the direction lateral to the substrate, we call it a lateral tunneling unit (LTU). Because of its layout and fabrication process, the LTU is suitable for integrating with each other or with other microstructures on a single substrate. This paper describes the design, the fabrication, and an experimental result which shows LTU's ability to control tunneling current.

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A two-dimensional optical scanner suitable for integration in a plane structure has been developed. To make it vibration robust, a torsional vibration system with two degrees of freedom is adopted for the resonator, and the vibration system axis is matched to the center of gravity. Piezoelectric bimorph cells are used as the actuator to excite the torsional vibration. Algorithms of Luh, Walker and Paul, which are usually used for motion analysis of manipulators in robot engineering, were applied for deriving the equations. This optical scanner is capable of optical scanning in two orthogonal directions independently or simultaneously at a scanning angle of ±30 degrees or more. One-dimensional scanning is enabled by driving the bimorph cells with the resonance frequency of either of the two torsional vibrations. Two-dimensional scanning is achieved if the bimorph cells are operated by adding the resonance frequency signals of the two torsional vibrations.

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