センサ・マイクロマシン部門（E部門）では，生体情報をセンシングする技術に関連した論文・レターを集めた特集号を企画し，本誌の2018年12月号で今回の特集号を発行する運びとなりました。

人工知能，ビッグデータの急速な進展において，生体情

In this study, we developed a flexible motion sensor that is able to be pasted to the body skin by embedding a hetero-core optical fiber sensor in a medical tape. The proposed sensitive tape detects the small stretch and bend without temperature compensation by using a simple equipment incorporating a light emitting diode and a photodiode. Firstly, a sensitive tape was tested the sensor performance for stretch and bend. Body joint movements were measured by the sensitive tapes pasted on the body. In addition, nursing movements were monitored by the eight sensitive tapes placed on body joint segments including the arm, shoulder, waist, and thigh. The differences of nursing movements were obtained by the sensitive tapes tracking the small change on the skin. The results showed that the proposed sensitive tape can detect the deformation of the skin only by being pasted on the skin and can measure the body motion without constraint to the body.

TSV (Through-Silicon Via) is a technology, which realizes an electrical connection from the surface to the backside of the silicon (Si) substrate, offering advantages of device minimization for bioprobe applications. To realize the TSV, copper (Cu) has widely been used as the via material. However, Cu cannot be used for a high temperature process (e.g., 700°C for Si growth process). To realize TSVs for high temperature processes, here we propose a poly-Si-based ‘two-step TSV', which consists of different hole sizes at the surface and bottom of the Si substrate. By utilizing deep reactive-ion etching (RIE), a 50-µm-diameter and 240-µm-depth hole was formed on the backside of the substrate, while a 12-µm-diameter and 10-µm-depth one was formed on the surface side of the substrate with the same alignment. The TSV is then filled with heavily-doped poly-Si, which is simultaneously deposited in the process of Si₂H₆ gas-based vapor-liquid-solid (VLS) growth of Si-microneedles. The current-voltage characteristics of the fabricated TSV show a linear behavior with a resistance of 6 kΩ, confirming the feasibility of the proposed TSV.

Blood pressure changes every second and cannot be continuously monitored by conventional cuff method. In order to solve this problem, we proposed a blood pressure estimation system by pulse transit time (PTT) method. The system includes two devices; a master device which monitors ECG for starting time of the pulse wave, and a slave device for monitoring the propagated pulse wave at the wrist. Both devices have some sensors, such as an accelerometer and barometer, for monitoring the condition of the body and wrist. The detected condition will be used for compensation of the PTT data. As a result, estimation of the blood pressure by PTT is accurate enough comparing to sphygmomanometer for home use. In addition, the relation between barometric pressure and PTT by hand position was measured and used for establishing the correction equations.

Scuba diving is a pleasant marine activity, but it is not without danger as diving is not a natural human activity. As a means of improving diver healthcare, we investigated the feasibility of measuring pulse waves inside a diver's mouth by using a photoelectric sensor mounted on the mouthpiece used by a diver for underwater breathing. Testing showed that the pulse waves can be measured at the gum. The results also showed that the measurement is easier when there is little or no pressure between the sensor and gum.

In this paper, we propose a method of construction of inter-vehicle network for coupling and decoupling vehicles. First, we describe the problems associated with construction of inter-vehicle network. Second, we propose two sequences of procedures how to solve these problems by grasping the connection matrix. Finally, we show the prototypes to which the method is applied, and we perform the test for function confirmation and evaluation of the method.