Alain Lee_imp said:
Hi GO,
Can you please describe/explain how the Yamaha "Self Cancelling" works?
Hey Alain:
I didn't tear one down. I just used them as a rider.
Given the era in which they worked, I suspected they were quite primitive. I don't mean mercury switch primitive, but possibly a voltage source detection primitive. There might be some online information.
I recall when the rider asserts a turn signal, the engine rev speed was either high (moving and possibly decelerating) or stopped and lower engine rev. In the first case the system voltage is high - maybe 13.5V. When stopped idling at a light the system voltage might be 12.4V. When the rider accelerates again, the engine speed increases and the system voltage transitions back up to 13.5V. Maybe a "capacitor-based timer" begins following the transition of low-to-higher voltage and when it completes, it kills the signal relay using a switching transistor.
Assuming this was somewhat the approach (and I really don't know), the problem was when the rider signaled during a constant velocity turn keeping a decent engine speed. In this case, the signals would often not cancel automatically (which I experienced) because the elevated system voltage was maintained. In addition, I also recall sitting stopped at turns with signals flashing and revving the throttle a few joyful times. That would also sometimes cancel the signals.
I don't recall auto signal cancelling during lane changes at speed working well either.
Of course today, this can all be nicely done in a lightweight digital embedded system and likely a reasonably organized state machine design around some reliable sensors.