Did FIRST mess up the game element drawings?

[ybansal17]

Our team has been putting together the different field elements, and when we were testing our chassis on one of the obstacles, we realized that some of the dimensions are off.

In the game manual and other field drawings, the ramp leading up to all defenses are supposed to be 12 inches (1 foot) elevated at a 13.5 degree angle, connecting to the platform with the obstacle at a height of 3 inches. However, in the CAD drawings for the ramp, FIRST says to use a 48" by 10" piece of plywood, which would mean the ramp is only 10 inches long, and the angle at which the ramp is elevated is much more than 13.5 degrees.

Additionally, the drawings and sizing specifications for the rough terrain show spacing for 3.5" x 3.5" blocks as opposed to the 3"x3" blocks FIRST says will be used during matches.

Has anyone else notices these inconsistencies, or are we just missing something?


--Yashna Bansal ('17)
Team 1967, the Janksters

[Mechvet]

It's not an error. There's usually a Team version of field elements, and then the competition version. The team version is more cost effective for teams to make, at the sacrifice of accuracy for coefficient of friction, spacing, and small dimensions.

In the past if the team versions of field elements were easy for your robot, the actual field was too.

[Jared Russell]

Originally Posted by Mechvet

In the past if the team versions of field elements were easy for your robot, the actual field was too.

This has varied considerably from year to year.

[MechEng83]

Originally Posted by Mechvet

It's not an error. There's usually a Team version of field elements, and then the competition version. The team version is more cost effective for teams to make, at the sacrifice of accuracy for coefficient of friction, spacing, and small dimensions.

In the past if the team versions of field elements were easy for your robot, the actual field was too.

The 2012 bridge is a glaring counter-example.

[Wayne Doenges]

Originally Posted by ybansal17

Additionally, the drawings and sizing specifications for the rough terrain show spacing for 3.5" x 3.5" blocks as opposed to the 3"x3" blocks FIRST says will be used during matches.

The GDC used the 3.5" dimension because that is what a standard 4" x 4" is. It would take some effort to create a 3" x 3" block.

On another note. On the wooden chin up bar, the 45 degree angle starts right at the top of the pipe but if you look at the manual it appears that the angle starts 2" above the pipe.

[rich2202]

Originally Posted by Wayne Doenges

It would take some effort to create a 3" x 3" block.

We are gluing 2x4's together.

Actually, that was the first idea. Someone else decided to order steel tubing in order to get the right friction.

[Blizzard3197]

Originally Posted by ybansal17

Our team has been putting together the different field elements, and when we were testing our chassis on one of the obstacles, we realized that some of the dimensions are off.

In the game manual and other field drawings, the ramp leading up to all defenses are supposed to be 12 inches (1 foot) elevated at a 13.5 degree angle, connecting to the platform with the obstacle at a height of 3 inches. However, in the CAD drawings for the ramp, FIRST says to use a 48" by 10" piece of plywood, which would mean the ramp is only 10 inches long, and the angle at which the ramp is elevated is much more than 13.5 degrees.

Would this be THAT much of a problem with building the field, as there is the difference with wood/steel with friction, etc? There have (at least I think) always been differences in the competition field and the team practice fields.

[ybansal17]

Thanks!

[MechEng83]

One thing we've noticed after having built the team field elements, the width of the team version of the defenses is shorter than the competition ones. We noticed this when trying to set up a full field, and the spacing just didn't line up properly.

The team platforms are 48" (the width of a standard plywood sheet) while the competition platforms are 52.5" wide.

[Taylor]

Originally Posted by MechEng83

One thing we've noticed after having built the team field elements, the width of the team version of the defenses is shorter than the competition ones. We noticed this when trying to set up a full field, and the spacing just didn't line up properly.

The team platforms are 48" (the width of a standard plywood sheet) while the competition platforms are 52.5" wide.

Have you been putting in the side shield spacers between elements?

[MechEng83]

Originally Posted by Taylor

Have you been putting in the side shield spacers between elements?

That didn't include them. They're functionally 3/8" thick, from what I can gather from the field drawings. We're making adapter pieces to make up the missing width and hold the shields between the defenses

[Jimmy Nichols]

Originally Posted by rich2202

We are gluing 2x4's together.

Actually, that was the first idea. Someone else decided to order steel tubing in order to get the right friction.

We ordered the steel cut to length from our local supplier who buy all our metal from. Even @ $82 for a full set I felt it was worth it to have the right driving feel. Plus the time savings.

[2544HCRC]

Great catch on the 12" ramp. A student came and showed me how the angle was correct and 10" didn't work. I shrugged it off but we did lengthen to about 11" to make the bottom of the ramp work. We were splitting the difference between the 12" that DID work and the 10" that DIDN'T work.