  Critical systems must be designed resilient to all kinds of malfunctions. We
are especially interested by the loss of control authority over actuators. This
malfunction considers actuators producing uncontrolled and possibly undesirable
inputs. We investigate the design of resilient linear systems capable of
reaching their target even after such a malfunction. In contrast with the
settings of robust control and fault-tolerant control, we consider undesirable
but observable inputs of the same magnitude as controls since they are produced
by a faulty actuator of the system. The control inputs can then depend on these
undesirable inputs. Building on our previous work, we focus on designing
resilient systems able to withstand the loss of one or multiple actuators.
Since resilience refers to the existence of a control law driving the state to
the target, we naturally continue with the synthesis of such a control law. We
conclude with a numerical application of our theory on the ADMIRE fighter jet
model.
