Japan Aerospace Exploration Agency

Ihi Corporation

Yusuke Maru

Hiroaki Kobayashi

Tetsuya Sato

Nobuhiro Tanatsugu

Takayuki Yamamoto

Hatsuo Mori

Takayuki Kojima

Takashi Ogai

Tsuyoshi Yagishita

Noriyoshi Mizukoshi

Satoshi Nonaka

Motoyuki Hongo

Shinsuke Takeuchi

An abnormality diagnosing method includes a model generation step of generating a simulation model of a monitoring target, an operation start step of starting an operation of the monitoring target, a measurement step of measuring an internal state quantity in the operating state of the monitoring target and extracting a measured value, a prediction step of inputting into the simulation model same control input value used in the operating state of the monitoring target and calculating a predicted value of the internal state quantity of the monitoring target, a Mahalanobis distance calculation step of calculating a Mahalanobis distance from a difference between the measured value and the predicted value, and an abnormality diagnosis step of diagnosing whether the operating state of the monitoring target is abnormal based on the Mahalanobis distance.

Abnormality diagnosing method and abnormality diagnosing system

An air intake includes a spike and a cylindrical cowl. The spike is composed of a plurality of plates which are arranged axial symmetrically around a central axis thereof, and the cowl includes an inner wall parallel to the central axis and is formed so as to enclose a rear portion of the spike via a given space. The adjacent ones of the plates form respective aerodynamic compressive surfaces in spaces formed by the adjacent ones. The distances between the adjacent ones of the plates are variable, and the distance between the forefront of the spike along the central axis and the cowl is variable.

Air intake and method for breathing air using an air intake

It is an object of the present invention to provide a flying object using a thin elongated nose cone with a small tip angle for reducing the air resistance during flying, wherein the maximum loading capacity can be increased without decreasing the volume efficiency of the flying object by limitations placed on the accommodation space, regardless of the structure thereof. In the flying object in accordance with the present invention, which comprises a nose cone in the tip portion, the nose cone portion has a compressed structure in the axial direction during accommodation and expands on the tip side in the axial direction during flying, due to an expandable nose cone structure such that a disk with a small diameter is disposed in the forward position and the disks with a successively increasing diameter are disposed in the axial direction. After separation, the nose cone expands in the axial direction, deep cavities are formed between the disks, and a fine elongated nose cone with a small tip angle is provided, whereby the air resistance is reduced.

Method for reducing resistance of flying object using expandable nose cone

Growing community of inventors

Kanagawa, Japan

Yusuke Maru