  Integrating the heterogeneous controllers of a complex mechanical system,
such as a mobile manipulator, within the same structure and in a modular way is
still challenging. In this work we extend our framework based on Behavior Trees
for the control of a redundant mechanical system to the problem of commanding
more complex systems that involve multiple low-level controllers. This allows
the integrated systems to achieve non-trivial goals that require coordination
among the sub-systems.
