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And any other traffic light engineers, I suppose. Thought this was neat:

https://www.vancouverisawesome.com/vanc ... ll-3601397

You rang?

While Lidar is a useful concept, its implementation can be tricky.  The angles must be precise, and the equipment must be "taught" to recognize a standard bus and distinguish it from a recreational vehicle or a long flatbed (with or without a load).  It must also learn the difference between an articulated bus and an 18-wheeler tractor/trailer arrangement.  Relying on only one identification system is asking for trouble.

Better results can be obtained with a combination of systems -- OCR cameras, MIRT emitters and receivers, RFID systems, and roadbed loops.  In such an arrangement, a "majority vote" (bus or not bus) determines the outcome.

Interesting.

Due to the location, I can't imagine any other type of vehicle stopping to make a left turn there - only buses are allowed to turn there, they just don't have a dedicated left turn lane.. so probability is if the vehicle is there & large enough, it's all but certainly a bus waiting to turn left.

If "only buses are allowed to turn there" worked in real life, they would need no such system at all.  The fact that they need to detect buses at all indicates that enforcement of the "Buses Only" rule may not be very effective.  Time will tell, however.

They don't have a dedicated left turning lane so they just sit there waiting for the light to change. This is to fix that - so the light changes and lets them turn. The turn is into a bus loop, so I can see why they want only busses to trip that vs. any car who happens to be stopped at the light.

Ahh ... Many nearby cities (here in Cali) use a combination Loop / MIRT / RFID system.

• The MIRT transmitter sends out a coded IR signal unique to each bus.
• The loop detects a large, low vehicle at the intersection.
• The MIRT system sends a signal to trigger the RFID system.
• The RFID interrogates a transponder in the bus, which responds with another unique code for that bus.
• The traffic lights cycle to give preference to the bus.

Note that if no MIRT signal or RF transponder is detected, or if the MIRT code and the RFID code do not match, the traffic lights remain in their default pattern, relying only on timing and/or occupancy of embedded loops, and not on the types of vehicles occupying those loops.

Oh, and one other thing ... when you drive up to an intersection, try to move as close to the crosswalk as possible, because if the forward-most loop is unoccupied, the lights will take longer to change, even if loops further back are occupied.