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Tetherbot License Plates


Jerry Palardy (Event Partner)
1 year ago

Some innovative students have created robots that have two or more parts that can essentially act as separate robots.  The parts are attached by a long tether containing motor wires going back to a single brain.  Here is a video of two such robots.  The following questions assume that these robots do not violate any rules in section 3 of the game manual and thus are legal.

In a match with tetherbots it may be difficult for the referee to quickly ascertain the alliance color of part of the robot.  For example, a tetherbot could pass inspection with license plates on opposing sides of the robot, even though part of the robot does not have a license plate once fully expanded.

The inspection checklist says:

Robot displays colored VEX Team Identification plates on at least (2) opposing sides, with only (1) color visible. R28

Rule R27 says: (Sorry, getting error trying to paste the text of the rule. Here is a link to the game manual.)

Although rule R27 has many details about license plates, it does not state the number of license plates required, but it does give the Head Referee latitude to ensure that the alliance color is abundantly clear.   

Even though robots are customarily expected to have only two license plates, should a Head Referee require that a tetherbot have license plates on opposing sides of each part of the robot that becomes separated after the match starts?  

Answered by Game Design Committee

The "red box" of R27 states the following:

The intent of this rule is to make it very easy for Head Referees to know which Alliance and which Team each Robot belongs to. Being able to “see through” a Robot arm to the wrong color License Plate on the opposite side of the Robot would be considered a violation of <R27a>.** It will be at the full discretion of the Head Referee and inspector at a given event to determine whether a given custom license plate satisfies the criteria listed in <R27>.** Teams wishing to utilize custom plates should be prepared for the possibility of this judgment, and ensure that they are prepared to replace any custom parts with official VEX License Plates if requested. Not bringing official replacement plates to an event will not be an acceptable reason for overlooking a violation of one or more points in <R27>.

It is impossible to provide a blanket answer that would encompass all hypothetical Robot designs or Match contexts. R27 intentionally provides Head Referees with full discretion to make this judgment call for a given Robot / Match / event. Whenever a rule relies on a Head Referee judgment call, we would always advise minimizing risks of a conflict by making it abundantly clear that the rule is not being violated.