Procedure. of separating the environment from animals was accomplished by detecting a temperature

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1 Materials Supplier IR Thermometer MLX90614 You-Do-It Electronics Sharp GP2Y0A02YK0F IR Range Finder RobotShop.com Green LED Mr. Loven Wires Mr. Loven Arduino Genuino Uno Mr. Loven Cardboard Amazon Electrical Tape Walmart 4.7 k Ω resistors You-Do-It Electronics 0.1μF decoupling capacitor You-Do-It Electronics Computer ASUS Arduino Software Arduino.cc Velcro Joanne Fabrics iphone Armband Amazon Laser Pointer (Laser Diode 5 MW 650 NM) You-Do-It Electronics Procedure RESEARCH OF POSSIBLE SENSORS To begin engineering the device, research was done on multiple different sensors that could have been used to differentiate between a surrounding environment and animals. The task of separating the environment from animals was accomplished by detecting a temperature difference between the animal and the surrounding area. The sensor chosen for the device was also compatible with an Arduino Genuino Uno. After looking through a multitude of viable options for the device, the MLX90614 Infrared Thermometer was chosen. The MLX90614 worked for this device because it could get a temperature reading of an object without coming into contact with the object. Once the sensor chosen to differentiate the surrounding environment from animals was chosen, a sensor was need that could measure the distance away from the animal. The sensor

2 required was a range finder. The difficulty in finding the proper range finder was that there are two major types of range finders: infrared and ultrasonic. Ultimately, infrared range finders were chosen because the direction in which infrared range finders are pointed in is more easily controlled than an ultrasonic range finder. The Sharp GP2Y0A02YK0F IR Range Finder was chosen to accomplish the task because the sensor could measure distances and was compatible with the Arduino Genuino Uno. CONSTRUCTION OF PROTOTYPE Following the purchasing of the MLX90614 IR Thermometer and the Sharp GP2Y0A02YK0F IR Range Finder, the sensors needed to be connected to the Arduino Genuino Uno. The connection setup for the sensor MLX90614 is shown in Figure 1* which uses capacitors and resistors. Figure 1* The diagram above shows the circuit connection to the Arduino for the MLX90614 IR thermometer.

3 To connect the GP2Y0A02YK0F to the Arduino Genuino Uno, wires were soldered onto the three output pins on the back of the sensor. These wires were then connected to their respective ports on the Genuino Uno, which were specified on the back of the GP2Y0A02YK0F. Once the sensors were hooked up to the Arduino Genuino Uno, two more attachments were added: a laser pointer and a green LED. The green LED had two wires, of which one connected to ground and the other connected to power. The laser pointer had two wires which were connected much like the way the green LED was connected to the Genuino Uno. WRITING CODE FOR DEVICE Once the setup of the attachments for the device was complete, the code for the sensors needed to be written. First, the Arduino library that was associated with the MLX90614 was downloaded. Then, modifications were made to the example code, provided by the library, that met the specific needs of the device. Initially, the MLX90614 only measured and showed two values: ambient temperature and object temperature. The code was altered such that when the MLX90614 detected an object temperature above the ambient temperature, the serial monitor would output the word animal. Additionally, the GP2Y0A02YK0F code was retrieved from the GP2Y0A02YK0F data sheet. This code was incorporated into the code for the MLX90614 so that the two sensors could work as a single unit. The newly altered code would allow for the serial monitor to both show when there was a temperature difference between what it pointed at and the environment, and the distance to that object. Code was then written for the green LED so that whenever the MLX90614 detected a temperature difference, the LED would light up. No code was needed for the laser pointer.

4 TESTING FUNCTIONALITY OF DEVICE After the setup of the sensors and attachments, as well as the code associated with them was complete, testing needed to be done. The test results would tell if the sensors accomplished the desired task of determining whether what it was pointed at was an animal or not, as well as measuring the distance from the sensor to the object. To begin testing, one of the two sensors needed to be tested. The GP2Y0A02YK0F range finder was tested first. The GP2Y0A02YK0F was setup in line with a ruler so that trial measurements could be taken accurately. A hand was placed at increments of five centimeters up until the 25-centimeter mark. At each of the five settings, 25 data points were recorded. The data points were the outputs of the sensor in the serial monitor within the Arduino program. For each data set, a graph was made to compare the measured distance shown in the output of the serial monitor to the actual distance. The graph illustrated the differences between what the sensor measured and what the actual distance was. The code in the sensor was reworked until the measurements were within 20% of the actual distance. Figure 2* The picture above depicts the setup used to test the Sharp GP2Y0A02YK0F IR Range Finder.

5 After the testing of the GP2Y0A02YK0F IR range finder was complete, the MLX90614 IR thermometer was tested. The testing was done by standing in front of the sensor to test whether the LED would turn on or not. The LED turning on would signify if the code and sensors were functioning. However, simply because the MLX90614 was working, does not mean that it was the most optimal sensor for the scenario. Multiple alternate sensors were researched. The most promising sensor was an IR thermometer of the same company and model, but with a lens that narrowed the viewing angle of the sensor. This sensor was then tested using the same code from the MLX CONSTRUCTING A CASE After the sensors were tested and were functioning, a container was constructed to serve as a protective case for the device. A cardboard box was taken apart and parts of the flaps were cut and trimmed to create a box that could hold the Arduino board as well as batteries for the device if needed. The cardboard container could hold the device and the sensors on it. Additional slots were needed for the case as there were protruding wires. Another slot was needed to allow a cable to connect the Arduino Genuino Uno to the computer to update the code from time to time. Electrical tape was used to hold the box together, as well as hold any loose wires in place. Once the box was completed, the box was attached to an existing iphone armband using Velcro. This addition to the device made it possible for the device to be worn by a user. Holes were cut in the cardboard for the sensors to fit through. The MLX90614 required a hole large enough so that the view of the sensor was not obstructed. Another hole was for the laser pointer to go through. The laser pointer was taped in place once put through the hole. Another hold was needed for the LED to fit through and be visible. The GP2Y0A02YK0F did not have a hole, but instead wrapped

6 around the outside of the container to the face of the container and electrical tape was used to hold the sensor in place. Figure 3* The picture above shows a top view of the cardboard version of the case. The whole device was tested by having someone put the device on their arm. Then, a hand was passed in front of the device at differing distances. If the LED lit up, it meant that the IR thermometer was indeed detecting a temperature difference between the environment and the hand. Additionally, if the laser pointer was pointing at the end, that signified that the direction in which it was pointing was sufficient. These tests were also done with a ruler next to the GP2Y0A02YK0F. The code was reworked until the distance given by the serial monitor was within 20% of the actual distance. If there was an error in either of the mentioned parts of the device, the container was looked over to make sure no sensors were being obstructed by anything. Furthermore, wires were checked to make sure that they were plugged into the proper ports. If there were still issues with the measurements, the code was looked over and changed again.