Framtagning av IoT-prototyp med LoRa och GPS

Sammanfattning: This thesis work has has been done at Sensative in Lund and the goal has been to build a prototype of a product which the company then may build further upon. The product aims to combine IoT with social responsibility by preventing drowning accidents with the data that is generated and sent via the product. Based of an initial description of the product provided by Sensative, the work then was divided into phases which include research, investigation, building of a prototype and programming of the system, and resulted in a prototype that can demonstrate the basic functionalities that the end product is suppose to have. The prototype can sense when it has been put into water by measuring the voltage between electrodes, and can also determine its position through the use of GPS and send the coordinates via the LoRaWAN protocol to a gateway once per hour or when an alarm triggers. Since the product is suppose to be worn by a user and powered by battery focus has also been put on trying to minimize power consumption by for instance using a motion sensor to determine if it is in use or not. The system is divided into a couple of distinct modes called Standby, Run, Warning, and Alarm where each mode contains its own set of code and conditions which will determine what happens next in the system. The system design also includes times when the microcontroller is put into to rest- or sleepmode in order to save further energy.