Improve nav to only use points in the middle of the hall as intermediaries.

[maxbogue]

The best way to accomplish this would probably be to edit the neighbor data so that every landmark only has one neighbor: a waypoint directing away from it in the middle of the hall.

[kberger]

I'm not entirely sure what you mean or how it would be an improvement over what we are doing now. Maybe sketch and attach an image of what you want?

[maxbogue]

Black is the wall with doors, blue is the graph, and purple is the A* result. We never want it to go along a wall, and we wouldn't want it to cut over to the hallway waypoint in the top example. Instead we want a corresponding hall waypoint for each door landmark.

[kberger]

Door landmarks are not neighbors, so the top case does not occur. I talked to Zack about the inconvenience of driving between adjacent doors a while ago and he didn't seem worried about it.

I think that the hall landmarks are a little too sparse, because at the moment we kind of have somewhere in between these two cases. By that I mean we have something close to the top case, but without the door-to-door edge so the robot (in the above case) would go from the right door to the hall landmark and then back-track somewhat along the edge to the left door.

[maxbogue]

That's odd; I saw the robot try to go along a wall once. Maybe it just navigated directly from near the one door to the other door because it was technically visible?

[kberger]

I think that might be a case of overlap between the start and goal zones, so that will happen between nearby doors in the current algorithm

[maxbogue]

Is there any way we could prevent it that would make any sense?

[kberger]

If we reduce the size of the goal and start zones, that would reduce the chance of them overlapping. I think it's at 4 or 5 landmarks now, if we reduce to 3 I feel like we should still get good nav results. If you're at a door and pull the nearest 3 landmarks, you'll get the current door and at least 1 hallway I would think...but you might still get an adjacent door.

As it is, it won't go from door-to-door unless the doors or adjacent (or maybe adjacent + 1) which might be okay behavior. "Oh cool, this door is right next to me...I'll just jump over there reallllll quick!"

[kberger]

Zack just brought up the part of this that I was not considering. I guess it is bad to jump between doorways because we have no side-facing obstacle avoidance, so we really do want to go back into the hallway.

A clever solution as not fallen from the sky into my head yet...I'll keep thinking. Hopefully we can come up with something that doesn't result in adding a crapload of landmarks to the map...