[EricH]

Same as in soccer.

Or, for a more in-depth answer, turn to Section 9.6.3.

9.6.3 Yellow and Red Card Rules
<T05> The Head Referee may assign a YELLOW CARD as a warning of egregious ROBOT or team member behavior. This will occur at the completion of a match, before the field is reset, and will be indicated by the Head Referee standing in front of the team’s PLAYER STATION and holding a yellow card in the air. In the first match that a team receives a YELLOW CARD, it acts as a warning.
<T06> After a team receives a YELLOW CARD, a yellow flag will be placed on their ROBOT at the beginning of all subsequent matches as a reminder to the team, the referees, and the audience that they have been issued a YELLOW CARD.
<T07> A team will be issued a RED CARD (disqualification) in any subsequent match that they receive an additional YELLOW CARD. This will occur at the completion of a match, before the field is reset, and will be indicated by the Head Referee standing in front of the team’s PLAYER STATION and holding a yellow card and red card in the air simultaneously. The team will still carry their YELLOW CARD into subsequent matches.
<T08> YELLOW CARDS do not carry forward between qualification matches and elimination matches. All teams move into the elimination matches with a clean slate.
<T09> If a team is disqualified during a match for a reason other than receiving an additional YELLOW CARD, they will receive a RED CARD. This will occur at the completion of a match, before the field is reset, and will be indicated by the Head Referee standing in front of the team’s PLAYER STATION and hold a red card in the air.
<T10> During the qualification matches, a team that receives a RED CARD will receive zero ranking points and zero qualification points. The rest of the team’s in their ALLIANCE will still receive the earned qualification points and ranking points.
<T11> During the elimination matches, a team receiving a RED CARD will cause the disqualification of their entire ALLIANCE for that match.