  In this paper, we consider issues relative to prescribed time stabilisation
of a chain of integrators of arbitrary length, either pure (i.e., where there
is no disturbance) or perturbed. In a first part, we revisit the proportional
navigation feedback (PNF) approach and we show that it can be appropriately
recasted within the framework of time-varying homogeneity. As a first
consequence, we first recover all previously obtained results on PNF with
simpler arguments. We then apply sliding mode inspired feedbacks to achieve
prescribed stabilisation with uniformly bounded gains. However, all these
feedbacks are robust to matched uncertainties only. In a second part, we
provide a feedback law yet inspired by sliding mode which not only stabilises
the pure chain of integrators in prescribed time but also exhibits some
robustness in the presence of measurement noise and unmatched uncertainties.
