Blocking a robot driving clock-wise

[Vikesrock]

The main issue here would not be impeding. Both of you are correct in saying that according to the rules you would not be impeding by preventing motion on the clockwise direction.

The issue is pinning. According to <G41> (quoted below) a robot deemed to be pinning an opposing robot must move to allow the other robot out within 6 seconds of the pinning signal by the referee. If a robot has it's arm up so it cannot proceed forward without tipping and you are behind them such that they cannot back-up or turn I would say you are most certainly pinning and would have to move within 6 seconds of the referee signaling the pin.

<G41> Permitting To Pass - When a ROBOT has received a signal to pass (see Rule <G38>), or
when the REFEREE signals that a ROBOT is pinning an opponent in place, the ROBOT
shall have 6 seconds to move out of the way and create a “passing lane” to allow the
opposing ROBOT through. ROBOTS that fail to do so within 6 seconds after the “signal to
pass” shall receive a PENALTY. Repeated infractions will result in a YELLOW CARD being
issued to the ROBOT.