2 Oct 2025

Modeling Thermocouple Placement in a CUBI Test Fixture

Abstract: This report describes an effort to model the response of temperature thermocouples mounted on a multisurface CUBI test fixture as a means to document potential thermocouple error sources. (CUBI is a euphemistic term that describes an assembly of contiguous cubic or rectangular solids.) The thermal solver within the commercially available Multi-Service Electro-Optical Signature (MuSES) Infrared (IR) was employed for modeling and analysis. Modeling was divided between the development of models to study individual temperature sensors and the incorporation of many such sensors into a full-up CUBI apparatus. The MuSES model of the simple plate in replicating analytic results to a high degree of accuracy, thus validating the MuSES solver. Additionally, MuSES modeled a CUBI fixture as a 2D shell in an outdoor environment. This model was run with and without attached sensors. The difference in temperature of a particular sensor and of the underlying CUBI surface with the sensor absent provided a prediction of the measurement artifact introduced by that sensor.

2 Sep 2021

Spatial and Temporal Variance of Soil and Meteorological Properties Affecting Sensor Performance—Phase 2

ABSTRACT: An approach to increasing sensor performance and detection reliability for buried objects is to better understand which physical processes are dominant under certain environmental conditions. The present effort (Phase 2) builds on our previously published prior effort (Phase 1), which examined methods of determining the probability of detection and false alarm rates using thermal infrared for buried-object detection. The study utilized a 3.05 × 3.05 m test plot in Hanover, New Hampshire. Unlike Phase 1, the current effort involved removing the soil from the test plot area, homogenizing the material, then reapplying it into eight discrete layers along with buried sensors and objects representing targets of interest. Each layer was compacted to a uniform density consistent with the background undisturbed density. Homogenization greatly reduced the microscale soil temperature variability, simplifying data analysis. The Phase 2 study spanned May–November 2018. Simultaneous measurements of soil temperature and moisture (as well as air temperature and humidity, cloud cover, and incoming solar radiation) were obtained daily and recorded at 15-minute intervals and coupled with thermal infrared and electro-optical image collection at 5-minute intervals.