directionally accurate car indicators

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.