I wonder if bikes should have turn signals? They'd help with maintaining a signal while you're waiting for clearance to turn, would be morevisible at night, and would allow two handed riding while signalling.
In another thread, I was asked how they could be made ("Talk through this a bit ... ). So I babbled the following:
For a road bike, rear ones on little booms sticking out from the seatstays above the wheel sight line, maybe total 12 inches apart. The half-power light distribution cones should be perhaps +-25 degrees from central axis. The booms should be rigidly attached to the seatstays, but able to flex and return or be straightened to resist permanent bending, and easy to correct if a large bend occurs while the bike is parked. LED with reflector/light director should be powered from a battery, and the battery float-charged either by a dynamo, an integrated solar panel (integral with the wheel? a photovoltaic dork disk?), or charged at home (no, this one is not float-charging). Size each lamp maybe 3/4 inch diameter each. dual thumb switches one on each hbar side. Similar lamps in the front, attached to hbars.
For a touring or commuting bike, integrate the rear booms with the luggage rack, or make a tail/turn rear lamp cluster.
In a more elaborate system they should share a power system with head/tail light, unified wiring harness in the frame (I know, getting a little constructeur here ..., but it needs to take up minimum space). Extruded flat-conductor cable manages heat extremely well, fits into small spaces, and is mechanically very robust. It can be folded to fit into little frame holes. I think the cabling should be neat and out of sight. The total power draw averaged over a ride for such turn signals is miniscule compared to head and tail lights, even LED, due to the low duty cycle. The power budget should also manage a brake light.
Problem here is designing the switches. The turn switches are easier for upright bars or trekker bars.
I see a lot of possibilities. Problems, too, but I think these are managable challenges. There's some curcuit design needed, probably to combine the output of multiple power sources, and to provide a regulated bus for the whole bike light system. It can be integrated into a powerful LED headlamp, like a Vega or Dinotte. With a dynamo, you can even add the USB charger for your cell phone or Garmin. An HRM can be on the same power system, with suitable voltage shifting. but now we're getting expensive.
Ok, put the power systems engineer back in the box now.
Any thoughts on some of these ideas? Has anyone seen much in the way of turn signals for bikes?