The full text of SG6 is quoted below, with some portions bolded for emphasis:
In addition to “grasp, grapple, or attach to”, you can also look towards the key words “latch onto” and “anchor” to help understand the intent of this rule. Some additional synonyms that are covered by the intent of this rule are “grip”, “pinch”, or “clamp”. These are all terms that describe active retention of the field element or opposing Mobile Goal, such that a robot mechanism is actively exhibiting force on multiple sides of it.
On the other hand, it is possible to “push”, “encompass”, or otherwise passively manipulate something without “clamping” to it. This is why scenarios like these are considered legal:
To answer your specific questions:
- The first image (the “claw” representation) would not be legal.
- The second image (the “U-shaped robot with red flaps”) would be legal if the “flaps” did not exist or were stationary.
- However, the second image would not be legal if the red flaps actuated inward (as shown by the green arrows) and “locked” the goal in place.