  Autonomous underwater robots typically require higher cost and time for
demonstrations compared to other domains due to the complexity of the
environment. Due to the limited capacity and payload flexibility, it is
challenging to find off-the-shelf underwater robots that are affordable,
customizable, and subject to environmental variability. Custom-built underwater
robots may be necessary for specialized applications or missions, but the
process can be more costly and time-consuming than purchasing an off-the-shelf
autonomous underwater vehicle (AUV). To address these challenges, we propose a
modular underwater robot, Modularis, that can serve as an open-source testbed
system. Our proposed system expedites the testing of perception, planning, and
control algorithms.
