A lightweight scripting engine for the Slocum Glider

Underwater Vehicle (AUV) capable of deployments lasting several weeks or months. The layered control architecture used by the vehicle is difficult to program and restrictive. As part of previous work we have developed a more flexible programming framework capable of performing dynamic feature tracking. However, the gliders new and more computationally capable Linux Single Board Computer (SBC) results in additional energy demands. In this paper, we describe a lightweight scripting engine we have developed to allow the execution of code as part of the glider´s existing layered control system. In this scheme, the SBC creates code and initiates remote code execution on the glider´s stock infrastructure. In order to save energy, the SBC may enter a low power mode during the remote code execution. The SBC may be woken up periodically, or by specified events encountered during remote code execution. The resulting system can provide the enhanced computational capabilities of the SBC system, but only in situations where it is necessary, thereby potentially enabling significant energy savings. The lightweight scripting engine is not restricted to our prototype system but can also be used on a stock glider. The engine provides an alternative programming infrastructure for marine science application programmers to implement and test novel algorithms for their vehicle, thereby enhancing the usability of a stock glider. Along with the engine, we have developed a higher level programming language and compiler, and showcase the flexibility of the system by using it to track a thermocline.