# Rule 1.3.2: path width center to center

Hello,

I have a question regarding the 2018 rules.

1.3.2 The width of the path is 30 cm from the center of the wall to the center of the wall, and may open into foyers wider than the path.

What is the point of this information if no wall width is given? This rule also contradicts

1.1.4 Doorways are at least 30 cm wide.

If the wall to wall center distance is 30 cm and doorways (that is a path limited by two walls) are at least 30 cm wide, the wall has a width of 0 cm (or at least very small given the 5 % tolerance rule).

The easiest solution to this problem is to either decrease the minimum doorway distance (for example to 28 cm, so that a wall can be up to 2 cm in width) or increase the width of the path (center to center) to 32 cm.

Or maybe somebody has a better suggestion?

Best,
Jan

Just one example why it is not a good idea to set the wall-to-wall distance to 30 cm:

This is how most of the arenas in Germany are built and I think the same applys to most other arenas. If the wall-to-wall distance will be set to 30cm, this arena is useless (or local competitions need to “override” this rule which would make it pointless again).

I hope I could make the problem clear. The best solution might be to define a minimum and maximum wall-to-wall distance and wall width, for example 30 cm to 32cm respectively 0.5 cm to 2cm. This should include all currently used arenas.

Best,
Jan

Hi Jan,
Rules regulate the world convention. We will leave that region to manage the regulations and regulations.
Also, we allow a tolerance of 5% for field dimensions.
If the range of dimensions is further specified, the dimensions are expanded including the allowable range.

Hi Naomi,

But the problem I described in the original post is still there. If the center-to-center distance is defined, the wall width should be defined as well, otherwise the information is not helpful because the path the robot drives through could have any size. The point of this rule is to define the size of the path, isn’t it?

Best,
Jan

We have not yet concluded which one is better to define the wall thickness or the width of the aisle.
I will answer after discussing at TC.

Hello,

In my interpretation, the distance between two parallel walls is 30cm. This allows for different wall thicknesses depending on local suppliers. Also, it is important to note that 30cm x 30cm “tiles” need to be placed within the maze. If the inside distance is less than 30cm the tiles would not drop into the maze.

For example, the rules state:
1.2.4 A tile is defined as a 30 x 30 cm space, which is aligned to the grid made up by the walls.

The rules can be revised to make this clearer.

In addition, the “foyer” is simply a space that is greater than one tile wide.
1.3.2 Paths will be approximately 30 cm wide and may open into foyers wider than the path.

Regards,
Steven Aizenberg,
RoboCup International 2018 Montreal Canada LOC

It is a discrepancy caused by changing only one of the rules.
A slightly different idea came up, so I will answer after consulting with TC.
2018TC Naomi