Proposal:Height Weight Length Restrictions

We need to be able to use relations for height, weight and length restrictions. I would have put that together with the turn based restrictions, but I feel that this suggestion will drown in all the discussions about how turn based restrictions should work, that I feel it needs a separate proposal.

This restriction will apply for either a way (length of way with a certain weight limit) or a node (a point of the way limiting the max height of a vehicle).

In practice

For this relation to have any practical use, a suggested detour or bypass should be added, so where a routing software wants to pass a point with restriction, it should be referred to a safe way to pass this restriction. If no such safe bypass exists, than the simple tag on the way or node itself should be enough to prevent the vehicle to pass, and calculate a different route.

Examples

• Height: For tunnels and roads passing under physical structures, limiting the possible height of vehicles following the road.
• Weight: For bridges and roads where high ground pressure might damage the road or cause other problems. Can be divided into shaft weight, boggy weight and total weight.
• Length: For roads where physical barriers on curves prevents long vehicles passing.
• Width: For roads that passes physical barriers that limits the width of a vehicle passing.

Example 1

The main highway passes under the railroad track. The height limit to pass under is 2.8m

-----------x---------
  \--------------/

• type=height
• height=2.8
  • member=x
  • member=the way bypassing x, role=bypass

The primary way is tagged highway=primary, the bypass is tagged highway=unclassified and is significantly longer, it also contains speed bumps and other things that most routing software tries to avoid.

Discuss

Please discuss on the talk page.