New sensors for surface profilometry-tapping styluses, have been developed. During measurements, they tap surface to reduce scratching force of stylus and enable non-destructive measurements like AFMs. Microvibrators such as a quartz resonator, a micro-fork and a PVDF biomorph are used for the tapping and force sensing. This paper describes the principle of the tapping stylus, measurement characteristics of the three styluses, measurement results and features of the tapping styluses.

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Many force sensors used in robots use strain gauges. Because they have an analogue output, these force sensors are readily affected by electrical noise. They also often require amplifiers, low pass filters and AD converters. However, force sensors which use quartz resonators are robust to electrical noise since the output is a frequency which shifts in response to a change in an external force. The output frequency can be converted easily into a digital signal through a frequency counter. This type of force sensor also has quick response, high sensitivity, high resolution and wide bandwidth. Although force sensors with quartz resonators have many advantages, as mentioned above, such sensors have not yet been applied to measuring dynamic force such as in a contact force and position sensor. In this paper, a finger with four pairs of quartz resonators as a contact force and position sensor is proposed. The finger can detect two components of contact force and one-dimensional contact position along the finger. The performance of the finger was examined experimentally. As an application of the finger to sensing an environment, the two-dimensional shape of an environment was reconstructed by tracing the surface with the finger.

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A quartz-core cantilever fabricated from an optical fiber tip is proposed as a practical sensor for measurement of various physical quantities. Its operation is based on the principle that the resonance characteristics of the photothermally vibrated cantilever vary with the surrounding physical quantities. The cantilever is studied as a mechanical sensor for monitoring film thickness, liquid density and viscosity using a excitation vibration and detection system constructed solely of optical fiber. Thickness monitoring of Au film is possible with an accuracy of 0.5nm up to a thickness of 500nm. By utilizing the cantilever in liquid, the resonance frequency and half-power width dependence on the density and viscosity of the liquid were determined.

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A new design for a "double-frame" vibratory silicon gyroscope is described. The gyroscope consists of two frames and corresponding springs. The inner frame has electrode fingers and is suspended from the outer frame, which has sensing springs. The outer frame is linked to the substrate by driving springs. This decoupling of the lateral driving and sensing motions makes the structure easy to design and improves the S/N ratio. The gyroscope has a glass/silicon/glass structure with through-hole electrodes on one face. It is fabricated by the deep dry etching of silicon and low-pressure wafer-to-wafer anodic bonding. The noise equivalent angular rate is 0.8°/s (rms, bandwidth: 40Hz), and the linearity is less than 1% for angular rates from -250 to 250°/s. The overload resistance is over 1500G for 0.5ms, and the reliability of the package has been confirmed.

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Under the condition that the two resonant frequencies of driving and detecting modes are different, the sensitivity of a piezoelectric vibratory gyroscope decreases remarkably. In this paper, a method to avoid adecrease of the sensitivity is proposed, and the results on the equivalent circuit consideration and the experimental inspection are also shown. The method is realized by connecting an inductance element to the detecting side in parallel. The vibratory gyroscope has the high and constant sensitivity within a designed frequency bandwidth because a band-pass filter circuit is formed by this connection. As the resonant frequency of the driving side can be freely set in the bandwidth as a result, degrees of freedom for the vibratory gyroscope design increase fairly. The bandwidth on the frequency response characteristic also becomes wide. The validity of such the method that realizes the high sensitivity was confirmed experimentally.

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We examined the vabrational characteristics of a silicon 3D structure and considered the possibility of their applications. The silicon 3D structure with the cavity between the seismic mass which exists at the center of a chip and the beam which suspends the seismic mass has been realized. By using the 3D structure, the piezoresistive accelerometer was fabricated and it was obtained that the sensitivity for X-axis, Y-axis, and Z-axis component were 0.4-0.5mV/(m/s²) respectively. We also measured the frequency response of the piezoresistive accelerometer on condition that it was drived by a stacked piezo-electric. Additionally, we detected the angular velocity of the piezoresistive accelerometer and obtained the good agreement to the theory. Finally, we were able to verify the possibility of applying the silicon 3D structure to an angular rate sensor on the basis of experimental results.

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Parallel beam structure has many significant features, as follows. (i) The tip moves in parallel at the end. (ii)This structure converts the small displacement into the large strain. (iii) Each unit doesn't interfere to the other units by piling up this structures. We used this structure for piezoelectric vibrating gyroscope (angular rate sensor). In this paper, we analyzed features of the parallel beam structure by Finite Element Method, and showed that the resonance frequency of the drive unit and the sensor unit can be easily adjusted by changing the mass at the tip. From this result, this structure suits for the gyroscope. Experimental results are shown.

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Recently, micromachined vibratory gyroscopes are in the lime light. Especially, the double resonant mode is important in order to improve the sensitivity of micro gyroscopes. For such a purpose, some membrane structure of the micromachined gyroscopes have been reported. In this paper, we show the design strategy of the membrane spring for noting the resonance characteristics. In the paper, by measuring the fabricated devices and some simulations, we pointed out that the through knowledge of a nonlinearity of the membrane spring is important for micro structures.

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In this paper, we present a novel micromachined galvano-mirror. In the device, the mirror structure is made of the fluorinated polymer (CYTOP^®) in order to obtain high-speed response (i.e. light-weight mirror structure). The fluorinated polymer has a resistance to the anisotropic etchant, TMAH etc., the fabrication process becomes simple by using this polymer. The coil which makes torque to the mirror is made by electroplating metal, resulting in large cross-sectional area of the coil and enabling high current through the coil. We shows the fabrication process steps, measured mirror flatness and resonance characteristics.

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Recently, many micromachined vibratory gyroscopes are proposed. Almost all the devices have been made efforts to obtain the double resonant mode in order to improve the sensitivity of micro gyroscopes. Nevertheless, there are some difficulty to obtain the accurate structure for consistent resonant frequencies between reference vibration and detection vibration in fabrication steps. In this paper, we show the design strategy of the high sensitive vibratory gyroscope using the hard spring effect positively. We propose the method for adjusting vibrating frequency and show the example of the actual device and some measured data for high performance devices.

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