This device measured acceleration by means of a gyroscope, which was mounted in such a way as to act as a pendulum. The resulting mechanism performed a mechanical integration of the measurement of acceleration, which by Netwon's calculus gives the velocity. Because the gyroscope acted as a pendulum, and because the properties of the gyroscope gave the mathematical inegration of acceleration, it was called a "PIGA," for "pendulous Integrating Gyro Acclerometer." The "25" referred to the diameter of the housing for the gyroscope rotor, 2.5 inches (about 6.3 centimeters).
Among the several ballistic missiles and spacecraft that used these devices was the Titan II Intercontinental Ballistic Missile, which was also used to launch m,anned and unmanned Gemini space capsules.
The MIT Instrumentation laboratory, of Cambridge, Massachusetts, designed this device; it was manufactured by the AC Spark Plug Division of General Motors.
Display Status
This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Country of Origin
United States of America
Type
INSTRUMENTS-Navigational
Manufacturer
AC Spark Plug Division, General Motors Corporation
Dimensions
3-D: 19.7 × 11.4 × 10.8cm, 2.4kg (7 3/4 × 4 1/2 × 4 1/4 in., 5.2lb.)
Materials
Aluminum
Steel
Copper Alloy
Plastic
Rubber
Synthetic
Paper
Coating
Unknown Metal
Ceramic
Inventory Number
A20090048000
Credit Line
Gift of Delphi Electronics & Safety
Data Source
National Air and Space Museum
Restrictions & Rights
Usage conditions apply
For more information, visit the Smithsonians Terms of Use.