It did look like you tipped them on purpose.
FIRST needs to change their rules, and it needs to go something like this:
(Some is the same)
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1) No robot can have a device to intentionally damage another robot or aspect of the playing field
2) No robot can have a 'powered' device (pneumatic or motor) to get underneath another robot.
3) A robot may not tip another robot by wedging them between themselves and a part of the playing field.
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This would make wedges ok, but catapults illegal, and would also eliminate the no tipping rule. If two robots are pushing up against each other in a match and one is tipped, it should be alright. It is wrong however to tip a robot when they can't back up and run away essentially.
Either this, or they take away the tipping rule entirely. Maybe then teams will start developing clever ways to upright themselves
