  This paper introduces a novel attitude controller for spacecraft subject to
actuator saturation and multiple exclusion cone constraints. The proposed
solution relies on a two-layer approach where the first layer prestabilizes the
system dynamics whereas the second layer enforces constraint satisfaction by
suitably manipulating the reference of the prestabilized system. In particular,
constraint satisfaction is guaranteed by taking advantage of set invariance
properties, whereas asymptotic convergence is achieved by implementing a
non-conservative navigation field which is devoid of undesired stagnation
points. Multiple numerical examples illustrate the good behavior of the
proposed scheme.
