The most important part of a train ticket is its magnetic stripe.
As long as it's readable, a train ticket can go through a human barrier. But if the magnetic stripe is damaged, it cannot go through an automated barrier.
So it's vital to protect the magnetic stripe during the transportation.
Pigeon rucksack prototype 2.0
I altered the fundamental structure of the rucksack. I realised it should not go around the pigeon's wings. I referred to photographs of an experiment by a company to send a SD card
using a homing pigeon. The improved version of the rucksack uses fine mesh material and Velcro. It's a bit like a dog's harness, it goes under its stomach. It looks like as if it's wearing
a nappy.