Hiroshi Hosaka

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Personal area networks would benefit from a wireless communication system in which a variety of information could be exchanged through wearable electronic devices and sensors. Intra-body communication using the human body as the transmission medium enables wireless communication without transmitting radio waves through the air. A human arm phantom is(More)
A local positioning system utilizing propagation loss of Bluetooth wireless technology is developed for indoor human positioning. The distance between a fixed station and a mobile station carried by a person is derived from the propagation loss. The position of the person is calculated from distance measurements on three different fixed stations. The(More)
Shoes for measuring foot pressure distribution pattern were developed and the algorithm of action patterns (walking, running, standing, sitting, squatting) recognition was derived. A wearable system which monitors human's movement by a wristwatch-type motion sensor and foot pressure sensing shoes that send data to a wearable PC via Bluetooth and infers(More)
The Smooth Impact Drive Mechanism (SIDM) is a linear piezoelectric actuator that has seen practically applied to camera lens modules. Although previous SIDM actuators are easily miniaturized and enable accurate positioning, these actuators cannot actuate at high speed and cannot provide powerful driving because they are driven at an off-resonant frequency(More)
Keywords: Smooth impact drive actuator Piezoelectric actuator Resonant vibration Micro electrical and mechanical system a b s t r a c t A smooth impact drive mechanism (SIDM) is one type of piezoelectric actuator that has been put into practical use. In previous SIDMs, soft-type multilayered piezoelectric elements with low mechanical quality factors were(More)
We developed a lifelog system that utilizes user's mobile phones. User's position, which is closely related to the user's activity and experience, is tracked by GPS in outdoors and by a newly developed positioning system utilizing signal strength of Bluetooth in indoors. The mobile phone is also equipped with a supplementary function that lets the user(More)
Hyperthermia-induced decline in cognitive performance is a moderate complication that poses challenges to the maintenance of safety. Although the underlying mechanism can be attributed to the disruption of brain networks, the propensity remains unclear. This study aimed to test the hypothesis that the extent of the alterations in cognitive performance is(More)
A radio positioning system which uses a PHS terminal and a radio beacon is developed to achieve a low-cost and high accurate positioning system for logistics. Since the PHS positioning error is several hundred meters, it cannot be used to find lost transport objects. In this system, a radio beacon is attached to the PHS terminal and their position is(More)
This paper presents a safety driving system that uses a seat belt motor retractor as a stimulating device for awakening the driver. When the driver becomes drowsy, the motor retractor applies additional tension repetitively in the seat belt to alert the driver. In the experiments using a driving simulator, the driver's drowsiness was detected by changes in(More)
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