  Chore division is a class of fair division problems in which some undesirable
"resource" must be shared among a set of participants, with each participant
wanting to get as little as possible. Typically the set of participants is
fixed and known at the outset. This paper introduces a novel variant, called
sequential online chore division (SOCD), in which participants arrive and
depart online, while the chore is being performed: both the total number of
participants and their arrival/departure times are initially unknown. In SOCD,
exactly one agent must be performing the chore at any give time (e.g. keeping
lookout), and switching the performer incurs a cost. In this paper, we propose
and analyze three mechanisms for SOCD: one centralized mechanism using side
payments, and two distributed ones that seek to balance the participants'
loads. Analysis and results are presented in a domain motivated by autonomous
vehicle convoy formation, where the chore is leading the convoy so that all
followers can enjoy reduced wind resistance.
