# Accession Number:

## AD0630890

# Title:

## A STUDY OF THE EFFECT OF MAN'S MOTION ON THE ATTITUDE AND ORBITAL MOTION OF A SATELLITE.

# Descriptive Note:

## Technical rept., Sep 64-Mar 65,

# Corporate Author:

## SYSTEMS ENGINEERING GROUP RESEARCH AND TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

# Personal Author(s):

# Report Date:

## 1965-12-01

# Pagination or Media Count:

## 147.0

# Abstract:

A mathematical model is developed and used for investigating the effects of mans motion on the attitude and orbital motion of an earth satellite. The model is obtained by writing the translational and rotational equations of motion for a rigid-body vehicle containing interconnected moving parts and then reducing these equations to a system consisting of a rigid-body satellite and a point mass man. For the particular portion of the model concerned with the perturbations in the satellite attitude, the equations obtained are found to be independent of the orbit of the vehicle. The solution to the system of equations is primarily restricted to the case determining the disturbance of a given satellite due to an astronaut walking on the surface. It is shown here that the disturbance of the attitude, due to mans motion, is of greater importance than the disturbance due to gravity gradient while the disturbance of the satellite orbit is of the same order of magnitude as that due to the oblateness of the earth. Except for some special cases which contain closed form solutions, the general equations are solved on an analog computer. In all cases studied, the magnitude of the constraint force between the astronaut and the spacecraft is seen to be small. However, the changes in the angular velocity and attitude of the vehicle are shown to be significant. Unlike the attitude of the vehicle, the orbit of the center of mass of the satellite is found not to be seriously affected by mans motion. Author

# Descriptors:

# Subject Categories:

- Astronautics