Title:
VIBRATION TYPE DIGITAL INTEGRATING ACCELEROMETER
Document Type and Number:
Japanese Patent JPS62185118
Kind Code:
A
Abstract:
An accelerometer transducer has a base holding a sheet normal to an input axis. The sheet is suspended from the base by a first spring arrangement for oscillatory motion in the way of limited angular excursions about a central axis lying in the sheet. A weight is spring-suspended from the sheet in a manner permitting displacement of the center of gravity of the weight along the input axis. Acceleration along the input axis varies the moment of inertia of the assembly consisting of the sheet and the weight about the central axis, altering the frequency of oscillatory motion by an amount functionally related to the magnitude of the acceleration. The sheet is driven at its characteristic frequency, and its frequency of oscillation is measured. In a preferred embodiment, a first transducer includes a weight suspended offset from the sheet in a first direction along the input axis, and a second transducer includes a weight offset from the sheet in the opposite direction along the input axis. The change of oscillatory frequency of the second transducer is subtracted from that of the first transducer to develop an output quantity linearly related to the acceleration. In a preferred embodiment, the sheets, springs and weights are micromechanical devices fabricated by semiconductor fabrication techniques. Electrostatic driving elements for driving the sheet, and a capacitive pick-off for sensing its vibration are also shown.
Inventors:
BAATON BOKUSENHOON
Application Number:
JP2265287A
Publication Date:
August 13, 1987
Filing Date:
February 04, 1987
Export Citation:
Assignee:
DRAPER LAB CHARLES S
International Classes:
G01C19/56; G01P15/08; G01P15/097; G01P15/10; (IPC1-7): G01C19/56; G01P9/04
Domestic Patent References:
| JPS60213814A | 1985-10-26 | |||
| JPS6073414A | 1985-04-25 |
Attorney, Agent or Firm:
Motohiro Kurauchi