Relief Displacement of Airborne Objects

Authors

Esteban Fernández-Juricic, Purdue University
Joe Crumpton, Mississippi State UniversityFollow
Morgan B. Pfeiffer, United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Sandusky, OhioFollow
Sathishkummar Saiappan, Mississippi State University
Jared A. Elmore, Clemson University
Landon R. Jones, Mississippi State University
B. Santhana Krishnan, Mississippi State University
Raymond B. Iglay, Mississippi State University
Bradley F. Blackwell, United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, National Wildlife Research Center, Sandusky, OhioFollow

ORCID IDs

Crumpton http://orcid.org/0000-0002-5932-2480

Pfeiffer http://orcid.org/0000-0002-1079-5295

Samiappan http://orcid.org/0000-0002-8443-883X

Elmore http://orcid.org/0000-0002-5980-1561

Jones http://orcid.org/0000-0003-1814-6115

Krishnan http://orcid.org/0000-0002-2880-5893

Iglay http://orcid.org/0000-0001-7300-7244

Fernández-Juricic http://orcid.org/0000-0001-5290-8078

Blackwell http://orcid.org/0000-0002-2628-8933

Document Type

Article

Date of this Version

2024

Citation

Remote Sensing Letters (2024) 15(9): 872-882

article doi: 10.1082/2150704X.2024.2387131

dataset doi: 10.54718/WXEG9194

Comments

United States government work

Abstract

The increasing availability of unoccupied aircraft systems (UAS, also referred to as drones) has led to their use in taking vertical aerial photographs at relatively small spatial scales. These photographs can be used to measure the distances between objects appearing in the photographs. However, relief displacement can cause an object above or below ground level to appear at a point in a vertical aerial photograph that is not directly in-line with the object’s actual location, causing a measurement error. A UAS was used in this study as a photographed airborne object because its location and altitude could be controlled. We were interested in predicting the horizontal distance of the UAS’s appearance from the centre of a vertical aerial photograph. Predictions of the location of the photographed UAS’s appearance in vertical aerial photographs over both level and sloped surfaces matched measured appearance distances within 0.06–0.48 m. This study shows that the relief displacement formulas typically used to compute the height of a vertical structure appearing in a vertical aerial photograph can additionally be used to compute the actual location of an airborne object (e.g., a flying UAS, bird, bat) if the object’s altitude is known or can be estimated.