Active vehicle optical alignment aid and a passive vehicle three-dimensional alignment target ensure proper orientation and alignment plus control of the closure range and rate between two bodies, one in controlled motion and one at rest

Beam, R. A.

Morris, D. B.

English

NASA Technical Reports Server

Guidance 
Reticle Pattern
Target 
May 1967	 Brief 67-10120 
NASA TECH BRIEF 
NASA Tech Briefs are issued to summarize specific innovations derived from the U.S. space program, 
to encourage their commercial application. Copies are available to the public at 15 cents each 
from the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia 22151. 
Visual Attitude Orientation and Alignment System 
An active vehicle optical alignment aid and a 
passive vehicle three-dimensional alignment target are 
used for proper orientation and alignment plus control 
of the closure range and rate between two bodies, one 
in controlled motion and one at rest. The alignment 
aid and target may be located other than at the sur-
faces required to be aligned. The visual aid is a small, 
lightweight, highly accurate and reliable optical sys-
tem designed to project a collimated optical alignment 
image for superimposition on a three-dimensional 
visual target on the body at rest.
In principle, the alignment aid device is similar to 
the World War II fighter aircraft optical gun sight. 
A light source projects the image to the pilot's right 
eye by means of a beam splitter or combining glass. 
The optical system is such that the image presented 
appears to be the same distance away as the target. 
Unlike etched lines on a window, or a ring and post 
type sight, it is not necessary for the head and eyes of 
the pilot to remain fixed in one position to maintain 
accurate alignment. While the image is projected to 
the right eye only, the pilot sights with both eyes open. 
(continued overleaf) 
This document was prepared under the sponsorship of the National 
Aeronautics and Space Administration. Neither the United States 
Government nor any person acting on behalf of the United States
Government assumes any liability resulting from the use of the 
information contained in this document, or warrants that such use 
will be free from privately owned rights.
https://ntrs.nasa.gov/search.jsp?R=19670000120 2020-03-11T20:46:02+00:00Z
The single eye projection keeps the system small and 
eliminates apparent parallax of the projected image 
caused by eye accommodation (focusing) and con-
vergence when target sighting during the final docking 
phase. 
The target on the body at rest must, in conjunction 
with the body-in-motion sighting aid, provide the 
pilot with a visual cue to align within 12 degrees of 
freedom (6 for each body: yaw, pitch, roll, and 3 in 
translation). When the two bodies are aligned in all 
axes, the standoff cross of the three-dimensional 
target appears in the center of the target base and the 
projected image reticle pattern appears centered 
around the outer diameter of the target base. This 
aligns the two bodies in yaw, pitch, and translation. 
Roll is aligned when the horizontal and vertical 
markings on the target and the projected reticle pat-
tern are parallel and oriented top to top.
Notes: 
1. This man-in-the-loop, ±6 degree of freedom 
visual targeting system should be useful in many 
applications where two bodies are to be docked or 
maintained in predetermined attitude relationships. 
2. Inquiries concerning this invention may be di-
rected to:
Technology Utilization Officer 
Manned Spacecraft Center 
Houston, Texas 77058 
Reference: B67-10120 
Patent status: 
Inquiries about obtaining rights for the commercial 
use of this invention may be made to NASA, Code 
GP, Washington, D.C. 20546. 
Source: R. A. Beam and D. B. Morris

of North American Aviation, Inc.
under contract to

Manned Spacecraft Center
(MSC-647) 
Brief 67-10120	 Category 02


Visual attitude orientation and alignment system

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server