Obstacle avoidance and altitude control for autonomous UAV

Drones or UAVs are quickly becoming a bigger part of today's society. Delivery servicesand transportation are elds were big development is being done. For the UAVs to beable to perform its given tasks safely more and more sensors are implemented.This report covers the development and implementation of a sensor system to helpan UAV to keep a xed altitude and provide proximity measurements of the environ-ment to avoid obstacles. The system is build around the ATmega328P microprocessorand uses I2C to communicate with the sensors. Measurements are ltered and pub-lished into ROS where the autopilot can reach the measurements and make decisionsbased on the readings. Additionally, simple algorithms to avoid obstacles have beenimplemented and simulated in the simulation software Gazebo. The altitude controlsystem which has been the main focus of the project has been implemented with goodresults in both simulation and real ight tests. The system will be used in a competi-tion held in Arizona, USA where the project team together with two other project willcompete in the prestigious CPS-challenge