  We explore boundary scattering in the sine-Gordon model with a non-integrable
family of Robin boundary conditions. The soliton content of the field after
collision is analysed using a numerical implementation of the direct scattering
problem associated with the inverse scattering method. We find that an antikink
may be reflected into various combinations of an antikink, a kink, and one or
more breathers, depending on the values of the initial antikink velocity and a
parameter associated with the boundary condition. In addition we observe
regions with an intricate resonance structure arising from the creation of an
intermediate breather whose recollision with the boundary is highly dependent
on the breather phase.
