Answered: SG8 and the Fence

Hi Karthik,

I have a series of related questions regarding how SG8 is applied to the fence. I have quotes the rule below and have bolded the parts where these questions stem from.

In all images the red surface shows where a robot is reacting against.

As per the way this is written it is legal to react against one side of an element. In relation to the Fence this could be the ‘front’ side. (The side facing the driver). Is this correct?


Assuming it is legal, would the separate parts that make up the Fence be considered part of the same element, or would they all be considered their own elements? This would allow a robot to react on multiple surfaces that are facing different directions. (The inner side of the vertical and top of the crossbar).


Assuming the fence is considered a single element and we can only react to one side of it, would it be legal to react to other ‘elements,’ such as the field wall? This could be used to essentially lock the robot in place which is against the intent of this rule.


In a similar situation as above, a robot expands in such a way that it locks itself to the fence, but it still only reacting on one side of the Fence. As per the current rule this is legal, even though it against the intent of the rule. Am I correct?
In this image black represents a red robot expanding so that it has locked itself to the the fence by only contacting the blue side.

(Top view)

I only ask because it seems like an easy way for a potential wallbot to anchor itself to the field while remaining within the scope of the current rules, even though it is against the intent of them. Of course a team that underwent this kind of strategy would be under extra scrutiny of <G12>.

Thanks ahead of time for your answers.

Yes, this is correct.

The fence is one element. However what you are describing would be considered grasping and/or attaching, thus illegal.

No, this is not legal. As you’ve stated above, this would be a form of anchoring to the field, thus illegal by <SG8>, quoted above.

This is illegal. The first line of <SG8> is very important. “Robots may not intentionally grasp, grapple or attach to any Field Elements.” The depicted robot mechanism would be considered to be grasping and attaching to the Fence.

Yes, these were good questioned which addressed some areas of the rules that may not have been clear.