Contact-based force and surface tracking with omnidirectional mobile manipulation
Abstract
Description
Mobile manipulators have the capability to perform various tasks in different environments
(terrestrial in flat or smooth terrains, underwater, aerial, outer space...). Yet despite their
potential, there are still few practical use cases where these robots are deployed to carry out
tasks autonomously. Aside from motion planning and control of mobile manipulators, the other
topic that we explore in this thesis is continuous force-tracking tasks. Tasks where a continuous
force is exerted on an external asset, for example in cases where the manipulator cleans a surface
by rubbing against or putting a probe in contact with an asset to inspect it.
All the efforts in this thesis were driven to this ultimate goal, to develop a control architecture
that enables an omnidirectional mobile manipulator to perform continuous force-tracking tasks
on a free-form external asset. The control architecture comprises various modules that tackle
the technical problems that arise to make these applications autonomously in relatively high
unstructured environments. The main problems addressed are force control, whole-body motion
planning, managing collisions between robot links and the external environment, and integrating
various robotic and sensing schemes in a holistic control architecture. To validate our proposed
mobile-manipulation framework, working demos have been implemented on an omnidirectional
terrestrial mobile manipulator designed to operate in flat indoor spaces.