Applied Research and Development of Falling Sphere Instrumentation.
Abstract
The report describes a falling-sphere system which was designed to determine air density at altitudes from 40 km to at least 140 km above the earth's surface. The principal sensor for the system is a triaxial accelerometer which is contained in a 10-inch sphere. The system enables measurements of the drag acceleration experienced by the sphere as it falls through the earth's atmosphere. The accelerometer has a spherical cavity which in turn contains a spherical reference mass. Drag acceleration causes the reference mass to be displaced within the cavity. Capacitive sensors, mounted in the walls of the cavity, monitor the position of the reference mass. Displacement is monitored along three axes. The axial components of displacement are converted to calibrated voltages which are transmitted to recording stations on the ground. Drag acceleration is calculated from displacement-time data. The operation of the system is described, and details of the accelerometer, the associated electronic circuitry, and the physical structure are presented. Calibration and test procedures are also discussed. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1975
- Accession Number
- ADA023484
Entities
People
- Clay D. Westlund
Organizations
- University of Utah