More Thermal Imaging

Introduction
The goal of this lab was to better understand the thermal heat transfer between objects and their surroundings. The better understanding of thermodynamics helps with the analysis for future infra-red (IR) data collection.

Methods

Figure 1. A RGB Image of the sousvide setup

In this lab, the method to image the temperature change of objects to collect data on their rate of heat transfer was by placing 4 3d printed planes into a hot water bath, and imaging it with an IR camera. Three of the four planes were frozen and one was put into a plastic bag with no air, one was put into a plastic bag with air, and one was put into a wool sock. Their was also a plane which was keep at room temperature and placed into a plastic bag with air. All planes were placed into the hot water bath and the IR sensor, specifically a Zenmuse XT2 camera, watched the airplanes to see how their temperature changed over time.

Figure 2. An IR image of the sousvide

Results 
Each of the 4 airplanes increased their temperature at different rates based on their enclosure. The locations of the planes in the images are; the frozen plane in the wool sock: top left, the frozen plane in the bag with air: bottom left, the room temperature plane in the bag with air: top right, and the frozen plane in the bag with no air: bottom right.

Figure 3. A RGB image of the planes in the sousvide

Figure 4. An IR image of the planes in the sousvide at the start
of the experiment  

The frozen plane placed in a plastic bag without air increased its temperature the most rapidly because it was in direct contact with the water, and it had no insulation to help slow the heat transfer. Waters thermal conductivity .58 Watts per meter kelvin, which means that water can transfer thermal energy at a high rate to objects submerged in it.

Next was the frozen plane in the wool sock, this planes rate temperature increase was slower than the first plane, because wool is a good insulator. Wool being a good insulator helped keep the plane cold as it prevents the heat from flowing from the hot water to the cool plane as easily as the plane in direct contact with the water. Wool thermal conductivity .0464-.0732 Watts per meter kelvin, which means the wool takes a while to transfer thermal energy through it, making it a good insulator to keep things warm or cold.

Finally the frozen airplane in the bag with air and the room temperature airplane in the bag with air increased their temperatures at the same rate. This rate was slower than the other plane that was in direct contact with the water because the thermal conductivity of air is much smaller than that of water. These planes were also slower to heat up than the wool plane. This is why a dry suit is used in cold diving situations because it keeps a gap of air as a layer of insulation between you and the water. Airs thermal conductivity .024 Watts per meter kelvin, which is very low, meaning that air is a really good insulator and has a very low rate of energy and it insulated the planes very well.

Figure 5. An IR image of the planes in the souvide at the
end of the testing. 

 The results of this lab showed the advantages of using an IR camera to analyse the rate of thermal change is that it is easy to see what is happening to the objects compared to taking their temperatures, which could interfere with the process. 

The two planes that remained the coldest for the longest period of time was the one frozen one that was in the bag with air and the frozen one that was in the wool sock.

Discussion
This application of a UAV mounted IR camera is most likely not one that you are going to use them for, viewing 3d printed planes in a sous vide, but their are other applications that knowing the rate of thermal energy transfer is important. An application that an IR camera on a UAV is helpful for is checking roofs of buildings to see how are insulated and where more insulation could be use. Another use IR cameras and the rate of temperature change is the ability to monitor structures, as thermal if one part of a structure is heated or cooled more rapidly than the other this can cause warping or fractures to develop. A UAS could use an IR camera to spot locations that conduct thermal energy faster than others. Finally IR cameras on UAS can be used to spot locations that are ideal for solar panel installation, as you want those areas to get a high rate of energy for a long period of time. In conclusion the use of IR cameras on UAS can help understand the rate of energy transfer in systems and at locations to improve the efficiency and safety of an installation.
Conclusion
In conclusion, an IR camera is a sensor that when mounted on a uav, can help either fill gaps in data collection on the temperature of objects or it can identify information that was not expected to be there. IR cameras play an important role in using uas to remotely sense thermal change, and providing important information to the clients.