  We numerically examine ballistic active disks driven through a random
obstacle array. Formation of a pinned or clogged state occurs at much lower
obstacle densities for the active disks than for passive disks. As a function
of obstacle density we identify several distinct phases including a depinned
fluctuating cluster state, a pinned single cluster or jammed state, a pinned
multicluster state, a pinned gel state, and a pinned disordered state. At lower
active disk densities, a drifting uniform liquid forms in the absence of
obstacles, but when even a small number of obstacles are introduced, the disks
organize into a pinned phase-separated cluster state in which clusters nucleate
around the obstacles, similar to a wetting phenomenon. We examine how the
depinning threshold changes as a function of disk or obstacle density, and find
a crossover from a collectively pinned cluster state to a disordered plastic
depinning transition as a function of increasing obstacle density. We compare
this to the behavior of nonballistic active particles and show that as we vary
the activity from completely passive to completely ballistic, a clogged
phase-separated state appears in both the active and passive limits, while for
intermediate activity, a readily flowing liquid state appears and there is an
optimal activity level that maximizes the flux through the sample.
