  Multi-robot platforms are playing an increasingly important role in warehouse
automation for efficient goods transport. This paper proposes a novel
customization of a multi-robot system, called Tactile Mobile Manipulators
(TacMMs). Each TacMM integrates a soft optical tactile sensor and a mobile
robot with a load-lifting mechanism, enabling cooperative transportation in
tasks requiring coordinated physical interaction. More specifically, we mount
the TacTip (biomimetic optical tactile sensor) on the Distributed Organisation
and Transport System (DOTS) mobile robot. The tactile information then helps
the mobile robots adjust the relative robot-object pose, thereby increasing the
efficiency of load-lifting tasks. This study compares the performance of using
two TacMMs with tactile perception with traditional vision-based pose
adjustment for load-lifting. The results show that the average success rate of
the TacMMs (66%) is improved over a purely visual-based method (34%), with a
larger improvement when the mass of the load was non-uniformly distributed.
Although this initial study considers two TacMMs, we expect the benefits of
tactile perception to extend to multiple mobile robots. Website:
https://sites.google.com/view/tacmms
