Excerpt from the article:

In the past, the zoo had always used horizontal sliding gates. But the relentless rise in health and safety standards had led to the design of an elaborate new warren of cages for the tigers. The simple horizontal gates would not fit in five of the locations and these gates would have to slide vertically. Initially I couldn’t understand why this was difficult; I only later realized the problems involved.

Tim Hunkin

Tim Hunkin trained as an engineer but became a cartoonist for a U.K. Sunday newspaper. He next made The Secret Life of Machines TV series and now runs an arcade of homemade coin-operated machines in Southwold, England. He wrote “Building with PLCs” in MAKE Volume 23.

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