Backing on to dock. B-Double. Aldi warehouse in Minchinbury, NSW Australia.
A-trailer(front) slides back on rail via electric motor and lever to connect with b Trailer (rear), with doors on both front and back of rear trailer to allow walk through loading / unloading.
Few years late but made a video explaining the technique used for anyone looking for some pointers. https://www.youtube.com/watch?v=eezMlfSS8qs