Indicators are great, but they are less than 100% foolproof. Particular issues include inexact left and right turns, obstructions so that other cars don't know where you started from, and accidental indicator cancellation.

Consider this: I am in the UK, driving on the left: a roundabout has four exits, and I want to turn right (road 4). The road on which I approach (1) does not meet the roundabout at a right angle, so on the immediate entry to it, I am actually turning left (towards road 2). Driver of car opposite me (road 3) who wants to cross to my side, cannot see my right indicator because the roundabout is a hump. Thus, my indicator has automatically cancelled on my left-veering and he has every cause to assume I may be going straight on - i.e. the road he is coming out of. So he enters the roundabout, and I also stay on it because I am actually turning right. I avoid going into the side of him, or taking his front corner off, because I am not going too fast.

What would solve this? I'll tell you what - IN ADDITION TO A CONVENTIONAL INDICATOR STICK, buttons at intervals around my steering wheel which I could press to indicate my absolute angle of intended turn. Thus, when I am approaching the roundabout and look to the road on which I intend to leave, it is at roughly 2 o'clock. I engage that button. A long orange arrow, usually laid flat on my roof, flips up and points to my exit road. As I veer left onto the roundabout, it pivots to remain resolutely aiming for my exit, until I leave the roundabout, when I press the 'disengage' button.

This also might be useful for those kind of traffic lights with filter-right lanes (left if not UK) where you're never sure quite what the local rules are ... but that might be a problem no-one else has so I'll leave it for now.
-- badgers, Jul 09 2003

bristolz's illo from days of olden buns http://bz.pair.com/fun/indicators.html
[thumbwax, Oct 04 2004]

JKew wants this http://www.halfbake...20Turn_20Indicators
and could have found it in the category list [badgers, Oct 04 2004]

Pop-up arrow. How 20th century. I'm seeing a laser projecting your intended path on the road in front of you.
-- Worldgineer, Jul 09 2003


Oh jeez, how many times have we done *this* one by now?
-- DrCurry, Jul 09 2003


// Thus, my indicator has automatically cancelled on my left-veering //

So put it back on: it's your responsiblity to be correctly indicating as you go around the roundabout.

// A long orange arrow, usually laid flat on my roof, flips up and points to my exit road. //

It seems to me the apparent direction this points in will depend on the angle at which it's viewed.

How about indicators which get faster and more insistent the more imminent the turn?

Actually getting drivers to *use* indicators on roundabouts -- and to use them correctly -- is a more pressing problem IMHO.
-- JKew, Jul 09 2003


Well, I have no idea how many times *you* have done "this one" by now, because there are no such ideas on this site. The linked picture is nice but involves light-indicators in the conventional place. My indicator is visible from all sides and is the width of the car, so that if I am head on to you and turning right you will have a complete side elevation of the arrow. If I am at a 3/4 angle to you, or if you are on my left, the arrow will not appear to be the width of my car. The important point is that it will be abundantly clear, if the arrow appears very narrow or is not pointing across your trajectory, that I intend to leave at your exit. The arrow indicator is unashamedly analogue, and does not involve the loss of concentration which is a potential effect of re-indicating while I am trying to steer on the roundabout. I don't mean to whine but I didn't imagine this little idea would be worth such condescension.
-- badgers, Jul 12 2003



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