Size and Distance Estimation from an Acrylic Submersible.
Abstract
In an experimental evaluation of the visual properties of NEMO, a 5.5 foot diameter acrylic submersible, it was found that size and distance of underwater targets (white discs) were dramatically underestimated. In many cases this underestimation was in excess of 50% of the true size and/or distance. This result however, is in partial agreement with theoretical predictions established for the optical properties of NEMO. The results of this experiment differ from theory in that error rates (amount of underestimation) maximize at distances of 20-30 feet, whereas theory predicts an increase in errors (underestimation) to much further distances. Several reasons are offered for this discrepancy, including water turbidity, individual set or bias, and the effect of experience. It appears that with training which includes accurate information on true target size and distance, operators can accurately estimate size and distance. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1971
- Accession Number
- AD0722320
Entities
People
- Charles L. Eversole
Organizations
- United States Naval Research Laboratory