Robust Sensor Nodes for Smart Savannas : with a specification in water quality

Abstract: Project Ngulia is a public-private partnership that aims at developing innovative cost-efficient technical solutions in Ngulia sanctuary, Kenya. The technologies assist KenyaWildlife Service (KWS) with improving the security of rhinoceros. So far they have, amongothers, developed a dashboard showing the status of the sanctuary. This thesis attempts toinstall a LoRaWAN network system containing a server and a gateway, and to develop anappurtenant end-device prototype sampling the pH, conductivity, and temperature of thewater holes in the sanctuary. The plan is for Project Ngulia to, later on, include the samplesfrom the end-device in the dashboard using the LoRaWAN network system. In addition,the thesis attempts to evaluate the advantages and disadvantages of using LoRaWAN inthis use case by both literature studies and by tests during the implementation.The total system was developed according to a model inspired by the NASA engi-neering design process, an iteration of six steps;Identify criteria and constraints,identify theproblem,explore hardware and possibilities,select an approach,build a prototypeandevaluate. TheLoRaWAN network system and the water sample prototype was in every iteration devel-oped on the basis of the design goals of robustness and power consumption.The final prototype was built upon an Arduino Pro Mini 3.3V 8MHz, the LoRa ra-dio transceiver SX1276 and the open source LoRaWAN library calledarduino-lmic version1.5.0+arduino-2. The gateway, however, was build on a Raspberry Pi 3 model B, the opensource library namedpacket ́forwarderand an iC880A concentrator which contains theSX1301 LoRa radio transceiver. The server used was the LoRaServer software. An ad-vantage of LoRaWAN is that the range of the LoRa radio signal seems to cover the waterholes of interest in Ngulia sanctuary quite good with five gateways. Another is that onegateway can handle up to 100 end-devices broadcasting data every 20 minutes or less. Adisadvantage, on the other hand, is the memory occupation the LoRaWAN protocol occu-pies in the end-device, limiting the number of sensors to be connected to each end-device.