  The Robotarium, a remotely accessible swarm-robotics testbed, has provided
free, open access to robotics and controls research for hundreds of users in
thousands of experiments. This high level of usage requires autonomy in the
system, which mainly corresponds to constraint satisfaction in the context of
users' submissions. In other words, in case that the users' inputs to the
robots may lead to collisions, these inputs must be altered to avoid these
collisions automatically. However, these alterations must be minimal so as to
preserve the users' objective in the experiment. Toward this end, the system
has utilized barrier functions, which admit a minimally invasive
controller-synthesis procedure. However, barrier functions are yet to be
robustified with respect to unmodeled disturbances (e.g., wheel slip or packet
loss) in a manner conducive to real-time synthesis. As such, this paper
formulates robust barrier functions for a general class of disturbed
control-affine systems that, in turn, is key for the Robotarium to operate
fully autonomously (i.e., without human supervision). Experimental results
showcase the effectiveness of this robust formulation in a long-term experiment
in the Robotarium.
