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Just wondering if anyone has stories of the CitySafety system working in the wild.<p>Also, would the CitySafety system prevented this accident: Image an XC60 stopped behind a car - both are ready to merge onto a highway. Watching the traffic on the highway, the XC60 sees that the coast is clear so accelerates - only the car in front doesn't go. Any ordinary car smacks the car in front. Will the XC60 rear-end the car in front?
 

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Re: Any Real-Life Experiences with CitySafety? (DCPattie)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>DCPattie</b> »</i></TD></TR><TR><TD CLASS="quote">...would the CitySafety system prevented this accident: ...the XC60 sees that the coast is clear so accelerates - only the car in front doesn't go. Any ordinary car smacks the car in front. Will the XC60 rear-end the car in front? </TD></TR></TABLE><p>Yes I believe it would rear-end the car in front.<p>The City Safety system, as currently implemented, is designed to apply the brakes if it senses an impending low-speed collision, <B>but only if the driver is not providing active control input</B>. In other words, if the driver is not paying attention and the car is coasting. In your example, the driver is deliberately accelerating if not steering the car, so City Safety will not activate. Likewise, if the driver is steering, or actively braking the car though not quite hard enough, City Safety will not activate because the driver is considered to be "alert" and in control.<p>If you watch people taking the City Safety demonstration test, you will see some percentage that hit the pylons or the balloon car obstacle. Those are the people that could not resist the urge to provide some brake, steering or throttle input, despite the instructions to drive 5-10 MPH and then lay off the controls as the car closes in on the obstacle.<p>Possibly in future generations of this technology, Volvo and other makers will choose to allow the system to second-guess the driver more aggressively. However, I think they are being deliberately very cautious in introducing these self-controlling features because of liability concerns. I am sure that despite all best intentions to improve safety and reduce injury & damage, there will soon be lawsuits which claim the safety system: should have intervened sooner, should not have intervened at all, is flawed in design, is confusing, should not have been included at all, should have been included on all models years before, etc.<p>
 

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Re: Any Real-Life Experiences with CitySafety? (jhalbert)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>jhalbert</b> »</i></TD></TR><TR><TD CLASS="quote"><p>Yes I believe it would rear-end the car in front.<p>The City Safety system, as currently implemented, is designed to apply the brakes if it senses an impending low-speed collision, <B>but only if the driver is not providing active control input</B>. In other words, if the driver is not paying attention and the car is coasting. In your example, the driver is deliberately accelerating if not steering the car, so City Safety will not activate. Likewise, if the driver is steering, or actively braking the car though not quite hard enough, City Safety will not activate because the driver is considered to be "alert" and in control.<p>If you watch people taking the City Safety demonstration test, you will see some percentage that hit the pylons or the balloon car obstacle. Those are the people that could not resist the urge to provide some brake, steering or throttle input, despite the instructions to drive 5-10 MPH and then lay off the controls as the car closes in on the obstacle.<p>Possibly in future generations of this technology, Volvo and other makers will choose to allow the system to second-guess the driver more aggressively. However, I think they are being deliberately very cautious in introducing these self-controlling features because of liability concerns. I am sure that despite all best intentions to improve safety and reduce injury & damage, there will soon be lawsuits which claim the safety system: should have intervened sooner, should not have intervened at all, is flawed in design, is confusing, should not have been included at all, should have been included on all models years before, etc.<p></TD></TR></TABLE><p>Actually, this description applies to adaptive cruise with collision warning. City Safety activates and will apply brake force IF the driver does not, but steering and throttle inputs will not defeat the system. In the demonstrations where the driver hit the obstacle, it was as you mentioned, a result of them applying brake pressure, but not enough to stop the car. I personally have accelerated at the last second and the car did in fact stop itself in time.
 

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Re: Any Real-Life Experiences with CitySafety? (T Schroeder)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>T Schroeder</b> »</i></TD></TR><TR><TD CLASS="quote"><br>Actually, this description applies to adaptive cruise with collision warning. City Safety activates and will apply brake force IF the driver does not, but steering and throttle inputs will not defeat the system. In the demonstrations where the driver hit the obstacle, it was as you mentioned, a result of them applying brake pressure, but not enough to stop the car. I personally have accelerated at the last second and the car did in fact stop itself in time.</TD></TR></TABLE><p>I'm not confusing City Safety with CDW - I have that also and it is a different system with different attributes (and pretty useful I think). I cannot say how <U>much</U> throttle input is required to over-ride the City Safety, but Volvo is very clear that throttle, steering and braking are all part of the equation.<p>From the owner's manual:<br><I>"Driver commands are always prioritised, which is why City Safety™ does not intervene in situations where the driver is steering, braking or accelerating in a clear manner, even if a collision is unavoidable."</I><p>Similar statements have been issued in various articles, videos and Volvo presentations. I'm not disputing your test experience, but they have been consistent about what to expect and not to expect from City Safety. The message is: Do not expect it to save you if you are actively controlling the car.
 

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Re: Any Real-Life Experiences with CitySafety? (T Schroeder)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>T Schroeder</b> »</i></TD></TR><TR><TD CLASS="quote"><p>Actually, this description applies to adaptive cruise with collision warning. </TD></TR></TABLE><p>Perhaps. In order for Collision Warning to work, the car has to be moving forward at least 17 mph and for the system to be active.
 

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Re: Any Real-Life Experiences with CitySafety? (DCPattie)

I would like too to hear real life cases how CitySafety (or CWAB) actually works. Does it give any false alarms/braking ?<p>I have been now using S80 first generation ACC+CW about 3 years and during that time sometimes CW gives wrong alarms. <p>One easy case is that if there are 3 lanes and one of the lanes (left most lane) is turning lane and at same time street is having a small curve. Then if there is a bus in the left most outer lane waiting to turn (other 2 lanes continues as usual), then CW will give an false alarm (driving speed 60km/h) as it detects bus as being in the same lane even it's not. Hence I'm always wondering in those case that would XC60 do a autobraking ?<p>It would be quite confusing if car would do a autobrake in 60km/h speed just becase of there was a bus in outer lane waiting to turn...
 

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Re: Any Real-Life Experiences with CitySafety? (turbot)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>turbot</b> »</i></TD></TR><TR><TD CLASS="quote">...I have been now using S80 first generation ACC+CW about 3 years and during that time sometimes CW gives wrong alarms. <p>One easy case is that if there are 3 lanes and one of the lanes (left most lane) is turning lane and at same time street is having a small curve. Then if there is a bus in the left most outer lane waiting to turn (other 2 lanes continues as usual), then CW will give an false alarm (driving speed 60km/h) as it detects bus as being in the same lane even it's not. Hence I'm always wondering in those case that would XC60 do a autobraking ?<p>It would be quite confusing if car would do a autobrake in 60km/h speed just becase of there was a bus in outer lane waiting to turn...</TD></TR></TABLE><p>I think they may have improved this behavior. In my XC60, I will get a Collision Detection warning (or a significant automatic brake application if Adaptive Cruise Control is on) when a car <U>is in the process</U> of moving out of my lane and slowing down to turn. The XC60 will not attempt to predict that the slowing car will complete its exit into the turn lane, and so it continues to track the car as a potential obstacle until it is <U>completely</U> out of my lane. In this situation, I would naturally be comfortable to maintain my speed because I can see the car ahead moving out of my way. (Arguably from a defensive-driving point of view, I should not depend on that assumption - he might change his mind at the last second so I shouldn't cut it too close.)<p>However, I do not see this problem at all (even on curved roads) if a another car is <U>already</U> in the adjacent turn lane and has not been previously tracked in front of my car.<p>Perhaps Volvo and their partners have improved the algorithms in the past year or two.
 

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Re: Any Real-Life Experiences with CitySafety? (jhalbert)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD><i>Quote, originally posted by <b>jhalbert</b> »</i></TD></TR><TR><TD CLASS="quote"><br>However, I do not see this problem at all (even on curved roads) if a another car is <U>already</U> in the adjacent turn lane and has not been previously tracked in front of my car.<p>Perhaps Volvo and their partners have improved the algorithms in the past year or two.</TD></TR></TABLE><p>It's good that improvement has happened and curved road case is not any more a problem. I think one key element is also the camera which is nowadays there (I only have the radar).
 
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