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      12-26-2013, 12:24 PM   #5

Drives: 2013 BMW ActiveHybrid 3
Join Date: Dec 2012
Location: NorCal

iTrader: (0)

Originally Posted by drob23
Originally Posted by glennQNYC View Post
Can anyone with "Active Cruise Control with Stop&Go" describe what happens when the front sensor is obstructed? Does the system scale back to conventional cruise control, or do you lose any/all cruise control until the sensor is cleared?
What do you mean by obstructed? You are going to cover the sensor housing with something or you mean there is some small wall in the way?!?

Stop and go ACC on most vehicles uses a combination of forward facing radars and a forward facing camera, i.e. a sensor fusion algorithm. The radars don't work well once the vehicle comes to a stop (or at low speed) and is where the camera works best. The camera is usually mounted in the rear-view mirror housing. I think it's also used for the auto-high beam.
I'm not sure what the BMW system uses, but my first gen Chrysler 300C in 2008 used a Hella supplied LIDAR state as the sole sensor. That was easily blocked by either snow accumulation or even heavy rain or direct sunlight, as typical for a LIDAR system. When it was blocked, there was no cruise control at all. It was bad enough that they eventually released a software update that allowed you to hold the cruise control switch to enable legacy cruise control mode.

Usually stop and go systems, as you mentioned, combines two sensor technologies. However, i would still expect that if either sensor reports a fault, the entire system will refuse to operate