This report documents the development of the Subwave, a remotely-operated underwater vehicle (ROV), and an artificial neural network based inertial positioning system. The Subwave uses the open-source ArduSub software framework, commercial-off-the-shelf hardware components, and several custom systems. It is designed as a platform for researching autonomous underwater vehicles (AUVs). The first step for an AUV is navigating waypoints, which requires the AUV to know its global position. Since global navigation satellite systems (GNSSs) are denied underwater, the available underwater positioning systems were surveyed and determined that all the available systems were too large and expensive for the Subwave. It was also discovered that the only consistent underwater positioning method was inertial positioning. So, experimentation began on a small, low-cost system that employs an artificial neural network to predict latitude and longitude using micro-electromechanical system (MEMS) inertial measurement unit (IMU) data as inputs, which would become the Neural-Inertial Positioning System.