Parachute Jump Testing of Portable GPS Receivers

Paul Braisted

Abstract:	The satellite-based NAVSTAR Global Positioning System (GPS) has the capability to provide real-time 3-dimensional position and velocity information. Most other navigation systems are 2-dimensional, they do not resolve altitude. This makes GPS particularly interesting for vehicles that do not maintain a constant altitude, such as airplanes and helicopters. Much has been published about aircraft as platforms for GPS receivers. There is a type of "vehicle" for which altitude is the most important dimension, the parachute jumper. Whether in freefall or flying under a parachute canopy, the skydiver is powered by gravity. Position, velocity, and acceleration in the vertical dimension are of vital importance. Altitude lost can never be regained, making it the primary resource to be managed. But until recently, GPS receivers have been too bulky, heavy, and power hungry to be safely carried by a skydiver. This paper presents the experiences and results of two series of tests in which portable GPS receivers were carried by a freefall parachutist. Position and velocity solutions were recorded during the jumps for later playback and analysis.
Published in:	Proceedings of the 1989 National Technical Meeting of The Institute of Navigation January 23 - 26, 1989 San Mateo, CA
Pages:	15 - 24
Cite this article:	Braisted, Paul, "Parachute Jump Testing of Portable GPS Receivers," Proceedings of the 1989 National Technical Meeting of The Institute of Navigation, San Mateo, CA, January 1989, pp. 15-24.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In