[Long post warning - originally posted to Navigation Experts forum]

I've been experimenting with the use of un-named segments to get better navigation instructions. The rationale is thus: when Waze shows a turn onto an unnamed segment, it gives the name of the following segment instead. This can be useful in a number of scenarios:

Freeway/Highway Split
When a freeway or highway splits in two, you often need Waze to give keep left/right instructions for both continuations. The Junction Style guide suggests using 'wayfinder segments'. An alternative approach we've been trialing in the UK is to use a blank segment before the split, and then naming the following segments as per the road name.

Example: M1 / M621 split will give these two navigation instructions, which are easy to match against road signs:

• Keep left to M1 (N)
  or
• Keep right to M621 (W)

Split Ramps
When a single ramp exits from a Freeway, and then splits into two different directions. Often it is helpful to know which of the split ramps you will need before leaving the freeway. By leaving the first ramp un-named, Waze will do exactly this. This gives the driver plenty of notice to read the signs and get in the correct lane as soon as possible. They will then get another instruction to keep left or right once they've entered the ramp.

Example: M4 (W) to M25 will give one of the following two instructions to exit the Freeway (streetview):

• Exit left to M4 (W) J4b to M25 (S), then
• Keep left to M4 (W) J4b to M25 (S)
  or
• Exit left to M4 (W) J4b to M25 (N), then
• Keep right to M4 (W) J4b to M25 (N)

Example: The A1 (M) / M62 Interchange has no names on any of the connecting segments, and all routes through the junction will give the correct names. For each set of directions, the driver will see the name of the freeway that they will be driving on to before they leave the previous freeway.

To illustrate, this route* will give the following instructions: (*ignore out-of-date Livemap, and instructions from addon)

• Keep left to A1(M) (S), then
• Keep right to A1(M) (S)

Double Roundabouts
Sometimes 1 roundabout just isn't enough, so road designers put in two with a connecting link road in between. There's often not enough time to give appropriate instructions to allow the driver to get in the right lane while navigating between the two roundabouts. By leaving the link road un-named, Waze will give the name of the exit road of the second roundabout before the driver has entered the first. This gives the driver plenty of time to read the road signs and move into the appropriate lane.

Example: Hopgrove Roundabout has two roundabouts and a short link between them. As you approach the junction from the south, you really do need to be in the right lane (streetview). Here, Waze will give three possible sets of instructions:

• At the roundabout, take the second exit to A64 (E)
  or
• At the roundabout, take the first exit to A1036 - Malton Rd, then
• At the roundabout, take the first exit to A1036 - Malton Rd
  or
• At the roundabout, take the first exit to A1237, then
• At the roundabout, take the second exit to A1237

Traveling in the opposite direction, e.g. from A1237 to A64, Waze will say which direction to go before the first roundabout:

• At the roundabout, take the second exit to A64 (E), then
• At the roundabout, take the first exit to A64 (E)
  or
• At the roundabout, take the second exit to A64 (W), then
• At the roundabout, take the second exit to A64 (W)

Pictures!
Caveat: TTS will not read out the name of the following segment, but it does display on the client.


Does this make sense? Can anyone see any problems with these scenarios? Is there any other scenario where un-named segments could be useful?