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Side Collision Avoidance - disappointing?

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Max*

Charging
Apr 8, 2015
6,679
3,841
NoVa
Today was the first time the side collision avoidance (not warning) activated.

I was driving behind a bus in the right lane, decided to change lanes to pass him in the middle lane. As I'm about half way through passing him, he starts drifting into my lane, and then abruptly back into his. During his drift into my lane, my car sounds a quiet alarm (not like TACC, where it's very loud) the right rear sensor turns orangish-red, the steering wheel (I was driving, not AP) turns hard as if AP is engaged, and the steering wheel moves the car SLIGHTLY to the left away from the bus, the steering wheel goes back to normal.

I was in no danger of an accident (unless he kept drifting into my lane). At first when the steering wheel got hard and moved every so slightly, I didn't realize what's happening. But it quickly dawned on me.


I guess I expected the collision avoidance to be more... abrupt? Like a hard pull to the left away from the bus if the car thought she was in danger.

Anyone else have experience with this? Was your situation similar or different?
 
I had an experience on the freeway yesterday that I *think* was Side Collision Avoidance. Freeway construction crews were building what looked like a new HOV lane with a concrete pillar in the center divider and a new set of temporary pillars between my lane and the new lane. All of a sudden my sensors turned red/orange and the car slides right into the next lane along with the steering wheel tightening up like it was on AP. Mine didn't feel "ever so slightly" though. It was harder than that and freaked me out. I felt lucky there wasn't a car there at that time as I torqued out of the steering. But in thinking back on it the temporary concrete dividers on the left were very close to my car and SCA may have thought it was a threat and saw the right lane was clear (if that's even possible).
 
Mine pushed me from the center of the lane to the left side, but it never crossed over.

Alright maybe it's not disappointing if it can change lanes or do a hard shift. This was my first experience with it, so I had to ask.
 
Has Tesla ever issued an exact description of what the car will do in these kind of situations?
I assume that they have made tests simulating this and made videos of it?
If so, it would be nice to see so we can know what to expect.
 
I've never had it do anything when a vehicle beside me drifted over into my lane. However, I wonder if there's a problem with tractor trailer trucks where the side sonar is looking under the truck and doesn't trigger.
I agree with you there could be an issue with MS seeing under taller vehicles along side. I've had 3 instances where semi along side me loose the side indicators in the MS IC that something is next to me when I'm right next to the semi but can see well under it into the other lane... It seems to be the semis that have very long areas between axles... the ones carrying strapped-on cargo (once it was without cargo), opposed to the semis that have large enclosed trailers that my MS seems to always see just fine. This is one of the thing that has me a bit spooked with Autopilot in its current form, so I tend to always have very firm hands on the wheel as semis come near, and I'm looking forward to the 7.1 implementation with possibly some enhancements along these lines.
 
Thanks OP, I wondered how it acts when AP is disengaged. It sounds like it did exactly what I read at some point (sorry no reference). Basically, that the wheel will resist your move in order to avoid contact. The fact that it went "normal" is probably because the sensors detected the bus moving away from you and no longer felt an imminent collision.

As I understand it, the car will not cross into other lanes to avoid a side collision.
 
Max*, since the bus didn't end up hitting you, obviously the existing maneuver was enough to avoid the collision. In my opinion the car shouldn't veer any more than it needs to, because an abrupt turn could actually startle a driver more than needed and potentially *cause* an accident.

With no condescending tone intended, why would you want it to turn more abruptly than necessary?

By the way, on Monday I was on I-64 passing a work van. As I was passing him at 70 mph in the left lane of the pair of northbound lanes (I was literally just about to engage autopilot as I had entered the interstate less than 20 seconds earlier), his turn signal turned on and he turned into my lane. I had no choice but to slide over. I ended up with 3/4 of my car on the grass and 1/4 over the asphalt shoulder, going 65 mph and slowing to get behind him. It was not pleasant.

It wasn't until his van started veering into my lane that I realized that his left side mirror was completely gone. Not broken, but gone. I was livid because clearly he didn't even look. To make things worse, I don't think he even realized that he pushed me into the freakin' grass.

I passed him 30 seconds later, and he had the nerve to tail me. Needless to say, I shared some words and a gesture or two with him.

I didn't notice side collision avoidance doing anything here, although it may have been. I saw it coming, so had already initiated the veer into the grass after I saw him signal and the van started to come over.

After this and a number of other close calls with other drivers taking me out--well--I'm getting a BlackVue for Christmas!
 
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My impression is that it's designed to move you over in your lane, but not to leave your lane. This is probably for the best as you don't want to cause a collision on one side trying to avoid one on the other. This limitation means it won't always avoid a collision, but even a few inches (or realistically up to a couple of feet) of movement is a whole lot better than nothing and will avoid a large number of incidents.

I also have to second what Todd Burch said, it's hard to call it disappointing when you didn't in fact have a collision. The fact there was no collision proves that in this particular case it did not need to take any more action.
 
Max*, since the bus didn't end up hitting you, obviously the existing maneuver was enough to avoid the collision. In my opinion the car shouldn't veer any more than it needs to, because an abrupt turn could actually startle a driver more than needed and potentially *cause* an accident.

With no condescending tone intended, why would you want it to turn more abruptly than necessary?

The bus wouldn't have hit me in either case, I would've changed lanes or hit the go pedal. I was in no danger of getting hit, this time. I've had other times where people would try to change lanes into me, and I'd need to abruptly maneuver out of the way and the side collision avoidance did nothing.

So I guess my thinking is that side collision avoidance (SCA, just so I don't have to keep typing it) should act like AEB. AEB doesn't engage unless it's an emergency, and when it does engage it's abrupt (or so I've heard, I don't think I ever triggered it). I would expect SCA to engage only in an emergency, and for it to maneuver away from the object that it's avoiding.

The amount of steering the car did to avoid the bus, was very minimal. Hence why I asked if this is normal, or if my case was minimal. If it's normal, than SCA is very disappointing. Almost like blind spot monitoring on 6.2. But someone upthread commented that SCA did a sharp maneuver for them when it thought it was in danger.

I get your question, you're right, in my case it didn't need to be abrupt. But I want to make sure that it CAN be abrupt when needed. And it had no need to activate today, but I would've liked it to activate at least a few other times in previous weeks/months since v7, but it never has.

I hope I explained what I mean.

By the way, on Monday I was on I-64 passing a work van. As I was passing him at 70 mph in the left lane of the pair of northbound lanes (I was literally just about to engage autopilot as I had entered the interstate less than 20 seconds earlier), his turn signal turned on and he turned into my lane. I had no choice but to slide over. I ended up with 3/4 of my car on the grass and 1/4 over the asphalt shoulder, going 65 mph and slowing to get behind him. It was not pleasant.

It wasn't until his van started veering into my lane that I realized that his left side mirror was completely gone. Not broken, but gone. I was livid because clearly he didn't even look. To make things worse, I don't think he even realized that he pushed me into the freakin' grass.

I passed him 30 seconds later, and he had the nerve to tail me. Needless to say, I shared some words and a gesture or two with him.

I didn't notice side collision avoidance doing anything here, although it may have been. I saw it coming, so had already initiated the veer into the grass after I saw him signal and the van started to come over.

After this and a number of other close calls with other drivers taking me out--well--I'm getting a BlackVue for Christmas!

Ouch.

- - - Updated - - -

The fact there was no collision proves that in this particular case it did not need to take any more action.

See above. In this case it needed to do 0 action. And the slow action that it did seems useless. I would expect in other situations for it to do something, and if it'll be just as slow, it's completely pointless.
 
I would like more details on how this works. There are times when I feel it should warn me, but doesn't. I also had an instance when me, myself and I - human avoided crossing into a lane as the other driver came into the same lane. I felt that it should have warned me or given me an audible warning.
Other times, it seem slike the dashboard is late.

I do have a SC appointment to check it out.

In the end these are "assistance" features after all. And glad I have them, but I'd like to have more info on how and when it works and doesn't.
 
My wife's car reacted exactly as the original post described about a week after 7.0 was released. I was actually very impressed with it's operation. Keeping the car in the current travel lane and warning you of potential disaster is exactly how I would expect and want it to work
 
So I guess my thinking is that side collision avoidance (SCA, just so I don't have to keep typing it) should act like AEB. AEB doesn't engage unless it's an emergency, and when it does engage it's abrupt (or so I've heard, I don't think I ever triggered it). I would expect SCA to engage only in an emergency, and for it to maneuver away from the object that it's avoiding.

Maybe it does in fact act like this. Hopefully none of us have to find out firsthand.
 
I've had side collision avoidance trigger perhaps 5 times, in each case with a stationary wall. I can consistently encounter SCA when passing through a specific tunnel - where the tunnel wall is located at the edge of the (narrowed, due to the tunnel) lane. In other words, no shoulder.

In my estimation, SCA triggers when it detects that the wall is within approximately 2 feet. It is intrusive enough that I have avoided the leftmost and rightmost lanes of this tunnel while driving the Tesla.

If anyone is curious, this tunnel is where I-290 passes through the old post office building as you enter downtown Chicago.

My first encounter with the system was more alarming, as it occurred on a curve. I was "straightening the turn" on a tunnel off ramp and approached the outside wall towards the end of the ramp. The car detected the wall, sounded the alarm, and took over control of the wheel. At no point was I in danger of hitting the wall. There was plenty of tire grip left, so the car moved away from the wall and towards the inside of the turn. But it left me questioning the situation: had I reserved less available grip, would the car have still overridden the steering wheel? If so, side collision avoidance potentially could have upset the balance of the car and actually caused a collision. I decided not to (deliberately) test this theory.

All of my experiences have been with autopilot off. I have yet to have SCA activate due to a moving object (which is where I think it provides the most value). I'm contemplating the pros and cons of disabling SCA.
 
I disabled side collision avoidance (and warning) last night. I was mildly disappointed that side collision avoidance cannot be disabled separately from side collision warning.

Your experience is similar to mine (post #3 above) with respect to the wall although I don't think I was 2 feet from it, maybe 3 or 4. I haven't disabled it yet but am considering it. That is a crazy feeling fighting the steering wheel to regain control. Not fun.