Trailer hitch rules contradiction?

(http://forums.usfirst.org/showpost.php?p=23558&postcount=2)

How do we attach the Trailer Hitch on the BUMPER PERIMETER using hardware that must remain inside the BUMPER PERIMETER? I can’t see any way to follow the rule and meet the requirement in this GDC answer. Before I submit my own question officially, I wanted to find out if I was overlooking something that others see as an obvious option.

My guess would be that these connection devices only are considered for weight constrictions not volume constrictions.

I do not think you are overlooking anything. Drawing GE-09040 shows an example of how the trailer hitch should be attached using bolts that are at least 1.25 in long. Since the bolts have to be removed during the inspection process to weigh the robot with out the trailer hitch, I think the GDC assumes that you will not attach the bolts to the robot during the inspection process and instead will just weigh them with the rest of the robot. I think this is a simple case of the GDC assuming that anything that counts in the weight of the robot must count in the volume of the robot and not catching this obvious exception. I would submit the question.

I saw that too. I think it’s going to be like bumper attachments. (Going back to old rules …) bumpers were commonly attached via a bolt on the bumper going through the frame, held on by a nut. How many teams threw a handful of nuts onto the scale with the robot?

The ruling is consistent with previous rules. If the application of the rule by inspectors is consistent with previous inspections, the spirit of the rule will be met but the letter will not.

Go ahead and ask. But like any good lawyer will tell you, you don’t ask a question you don’t want to hear the answer of. Oh sorry, we’re not supposed to lawyer the rules. Strike that last comment from the record and instruct the jury to disregard it.

To add insult to injury, size must be checked without the hitch. Either the inspection box will allow it or the hitch will have to be removed for inspection. Watch for an update on this one.

Eesh, we just finished the frame design in CAD last night. It has a fiberglass panel as the back bumper perimeter, and then the steel hitch spacer and c-channel hitch mount went outside of that. The intent is for it to be removed via bolts during inspection.

Hopefully that update comes by Friday, as the original plan was to weld the frame next week. ^

No, GDC put on the Q&A:

Any hardware used to mount the Trailer Hitch is considered part of the ROBOT and not the Trailer Hitch. As such, it must be weighed and volume-checked with the ROBOT.

The specific method for mounting the Trailer Hitch to the ROBOT is left to the TEAM to decide, based on the particulars of their design. Note however, that an inadequate design that is not robust enough to keep the TRAILER attached to the ROBOT will result in a violation of Rule <G35>.

so the mounting IE the 7 inch bar along the robot is included. But is the actual swivel icluded

Ummm… what?

The Trailer Hitch is the 7" C-channel and the 7" spacer bar. Neither is included in the weight/volume.

And, to answer the original question, according to the Q&A, the hardware will be weighed and then checked individually to see if it adds volume.