  Suppose in a given planar region, there are smart mobile evaders and we want
to detect them using sweeping agents. We assume that the agents have line
sensors of equal length. We propose procedures for designing cooperative
sweeping processes that ensure successful completion of the task, thereby
deriving conditions on the sweeping speed of the agents and their paths.
Successful completion of the task means that evaders with a known limit on
their speed cannot escape the sweeping agents. A simpler task for the sweeping
swarm is the confinement of the evaders to their initial domain. The
feasibility of completing these tasks depends on geometric and dynamic
constraints that impose a lower bound on the speed the sweeping agent must
have. This critical speed is derived to ensure the satisfaction of the
confinement task. Increasing the speed above the lower bound enables the agents
to complete the search task as well. We present a quantitative and qualitative
comparison analysis between the total search time of same-direction sweep
processes and pincer-movement search strategies. We evaluate the different
strategies by using two metrics, total search time and the minimal critical
speed required for a successful search. We compare two types of pincer-movement
search processes, circular and spiral, with their same-direction counterparts,
for any even number of sweeping agents. We prove that pincer based strategies
provide superior results in all practical scenarios and that the spiral pincer
sweep process allows detection of all evaders while sweeping at nearly
theoretically optimal speeds.
