Update! (Inserted at the top of the article for reasons of importance.) Since writing this piece some 15 months ago, I have since discovered that some of the sources I used for it were based on garbled information about the filming of Series 3; although More Panda Monium was dropped during filming, that was an entirely separate incident to the one that resulted in injury (which happened when the robot activated without warning), and the name of the robot involved is not known. See this page on the Robot Wars Wiki for more information.
A kind-of, sort-of appendix to the Edit Wars series of articles, here, and specifically the fourth one. (The series has long ago stopped being about actual edits and more about stuff that happened backstage that wasn't mentioned on the show for obvious reasons, but there's not really a snappy title for that.)
As already covered there: there was a serious health and safety incident during the filming of the third series of Robot Wars, where a robot (by the name of More Panda Monium and pictured above, incidentally) malfunctioned in the pits and put its weapon through someone's foot, leading to some of the filming being shortened or cancelled outright because of the resulting health and safety investigation.
Now, in the same series, and also covered in that article, Pussycat was disqualified for using an illegal hardened steel blade that shattered on the arena wall. Were those two facts connected? If the first incident hadn't occurred, might Pussycat have been allowed to go through? Did the impaling lead to an immediate, much stronger enforcement of the health and safety rules?