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why no beep for backup sensor in Model 3? [rear cross traffic warning]

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There are things like this in terms of driver assistance gaps that add to my list of "how will FSD ever work with current hardware" questions.
If the car camera/sensors aren't enough to alert driver to cross traffic risk, then how well is the car going to back out of parking spots / execute 3 point turns / etc on its own?


The car self parks front-forward (which is objectively safer), so the intent is it never needs to back out of a spot.

3 point turns don't typically involve rear cross-traffic hidden by tight parked vehicles on both sides of you.
 
Exactly. So what’s Tesla’s problem?
It was pointed out in this thread already. It has no rear corner radars. All the other cars use rear corner radars to provide both rear cross traffic and blind spot monitoring.
https://www.continental-automotive....3007b4031/Rear-Cross-Traffic-Alert-EN.pdf.pdf

Discussed in depth in the Blind Spot Monitoring thread:
Blind Spot Monitoring

Basic gist is Tesla can implement better BSM if they want (currently it only warns or intervenes when you make an actual move into the lane; plus the recent update to show the camera), but they pretty much will never have rear cross traffic monitoring (as mentioned up thread, FSD will not need it either given it's designed to back the car in).

Basically there is nothing more available other than what the rear facing cameras already show when you back up the car.
 
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Agree 100%! My 10 year old Volvo has back-up warning beeps. I’m embarrassed to say that I’ve hit both of my sons’ cars backing my M3 out of my garage. I used the computer screen to guide me, but it showed that I had way more room than I actually had. Prior to getting this Tesla, I had only one minor accident in my 50 years of driving. Now, I’ve had two in six months, and both in my own driveway.
I don't think rear cross traffic warning is relevant to this. The 12 ultrasonic proximity sensors are however, and they already are active when you are moving the car slowly in parking situations. Are you saying they don't work in your car? In my Model 3, it makes noises when I move the car close to other cars when I park and as I get closer it shows the distance.

You can see where all the ultrasonic sensors are by looking at the front and rear bumpers and finding all the small circles on them. This picture shows all of them:
GUID-C4E89F56-EABB-47C3-97B8-C90D985BA3B2-online-en-US.png



You may need to make sure you have the sounds enabled in the menu:
Controls > Safety > Park Assist Chimes

See manual for more details.
Model 3 Owner's Manual | Tesla

Note if you have PPF on your car, you need to make sure there are holes from them already or your installer has cut out the holes. Otherwise the PPF may interfere with them working.
 
FWIW the ultrasonics are just about useless for this purpose.

Their max range is 24 feet.

Most studies put typical human reaction time for braking at 2-2.5 seconds.


A car moving 20 mph through a parking lot moves about 30 feet in 1 second.

Even at only 10 mph the car would cover the max range of the sensor in only 1.63 seconds.

Meaning they'd be useless to warn you about cross traffic.

I suppose if you tied AEB into it it MIGHT be useful, but AFAIK AEB only applies when moving forward, not backward.


tl;dr- Back into parking spots. It's objectively safer regardless of the tech on the car or not.
 
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Where I live in Brooklyn the parking beeps were going off all the time when squeezing by a double parked car/truck on narrow streets and were very distracting, and while parking too. I turned it all off. When I rented a Tesla in LA last week turning it off was the first thing I did as even pulling out of the wide spot where the car was set them all off. Doesn't anybody know how to park anymore without having the car bong at you when you are 2 feet away? If I think I'm close I'll use the screen to see how much room I have.
 
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The car self parks front-forward (which is objectively safer), so the intent is it never needs to back out of a spot.

3 point turns don't typically involve rear cross-traffic hidden by tight parked vehicles on both sides of you.
This is impossible in 45 degree angle street parking
I also question how the car will properly exit from a parallel parking spot

There's a lot "well it works for the easy 75% cases well enough 75% of the time" going on with FSD, which seems to violate the Full of FSD.
 
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Where I live in Brooklyn the parking beeps were going off all the time when squeezing by a double parked car/truck on narrow streets and were very distracting, and while parking too. I turned it all off. When I rented a Tesla in LA last week turning it off was the first thing I did as even pulling out of the wide spot where the car was set them all off. Doesn't anybody know how to park anymore without having the car bong at you when you are 2 feet away? If I think I'm close I'll use the screen to see how much room I have.
Right, the ultrasonics beep like crazy on entrance/exit from my tight 1970s suburban garage to the point of being pointless. I still end up having to slow and check all my mirrors&cameras.

In the city, the ultrasonics light up like crazy when parallel parking but at least the front/back distance indicators are helpful.

The ultrasonics can also NOT be relied on in complicated parking garage layouts with pillars and other protrusions. The ultrasonics only emit from a few fixed points, so you can end up hitting a protrusion when navigating a tight garage before one of the ultrasonics get tripped. It's similar to the ModelX FWD issue when you have ceiling protrusions it does not see.
 
This is impossible in 45 degree angle street parking

But at 45 degrees you're not blind backing out like you are at 90 degrees with big cars on both sides.

And you're generally backing into single-direction traffic too.


I also question how the car will properly exit from a parallel parking spot

Why would that be a problem? It already has side cameras that see backward into oncoming traffic and again there's nobody parked directly to your side blocking all views.


There's a lot "well it works for the easy 75% cases well enough 75% of the time" going on with FSD, which seems to violate the Full of FSD.

Nope. Back into 90 degree spots fixes that issue-and the 45 and parallel situations you don't have the blocked-view problem of 90 degree spots.
 
Right, the ultrasonics beep like crazy on entrance/exit from my tight 1970s suburban garage to the point of being pointless. I still end up having to slow and check all my mirrors&cameras.

In the city, the ultrasonics light up like crazy when parallel parking but at least the front/back distance indicators are helpful.

The ultrasonics can also NOT be relied on in complicated parking garage layouts with pillars and other protrusions. The ultrasonics only emit from a few fixed points, so you can end up hitting a protrusion when navigating a tight garage before one of the ultrasonics get tripped. It's similar to the ModelX FWD issue when you have ceiling protrusions it does not see.
I see you know what I'm talking about, yaknowaddimean? There should be a special Brooklyn version of the car!
 
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FWIW the ultrasonics are just about useless for this purpose.

Their max range is 24 feet.

Most studies put typical human reaction time for braking at 2-2.5 seconds.


A car moving 20 mph through a parking lot moves about 30 feet in 1 second.

Even at only 10 mph the car would cover the max range of the sensor in only 1.63 seconds.

Meaning they'd be useless to warn you about cross traffic.

I suppose if you tied AEB into it it MIGHT be useful, but AFAIK AEB only applies when moving forward, not backward.


tl;dr- Back into parking spots. It's objectively safer regardless of the tech on the car or not.
I'm assuming the person I was responding to was backing into stationary cars (given he/she was talking about misjudging the distance from the cameras), not moving cross traffic. I'm not trying to say they would be useful for rear cross traffic detection.
 
I've looked at threads and apparently I am in minority about feeling this should be an essential in the Model 3 standard that I got in December.
I have a Subaru Outback that is really superb for me in Florida with the crazy drivers here in parking lots etc. in terms of warning. I just don't feel like the rear camera gives me a broad enough picture.

While I am at it, the other thing that bothers me is that the screen showing adjacent cars in other lanes shows too much forward of car and far too little in terms of those coming up behind me. I would have thought that others would have felt this could be fixed better.

I will say this- if I had researched it more, despite all the great features, I don't think I would buy the Tesla again with these features missing.

Please don't put me down too much. Just my opinion.
I agree with you 100%. The 3 has
I've looked at threads and apparently I am in minority about feeling this should be an essential in the Model 3 standard that I got in December.
I have a Subaru Outback that is really superb for me in Florida with the crazy drivers here in parking lots etc. in terms of warning. I just don't feel like the rear camera gives me a broad enough picture.

While I am at it, the other thing that bothers me is that the screen showing adjacent cars in other lanes shows too much forward of car and far too little in terms of those coming up behind me. I would have thought that others would have felt this could be fixed better.

I will say this- if I had researched it more, despite all the great features, I don't think I would buy the Tesla again with these features missing.

Please don't put me down too much. Just my opinion.
I agree with you 100%. The 3 has significant blind spots and the cameras don’t do a good job of alerting the driver. I am backing into parking spots, but this is only half of the issue. Love the car; bad design.
 
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I agree with you 100%. The 3 has

I agree with you 100%. The 3 has significant blind spots and the cameras don’t do a good job of alerting the driver. I am backing into parking spots, but this is only half of the issue. Love the car; bad design.
Exactly
The amount of blind spots given the current sensor/camera suite and people arguing “the car can’t alert you / have these features“ as a result and “its fine cuz you should know how to drive with your mirrors!!” .. well OK, but how is this car supposed to FSD then?
 
Exactly
The amount of blind spots given the current sensor/camera suite and people arguing “the car can’t alert you / have these features“ as a result and “its fine cuz you should know how to drive with your mirrors!!” .. well OK, but how is this car supposed to FSD then?
Note there is blind spot monitoring in the Tesla, it just doesn't alert or intervene until it determines a crash is likely. That is not the desired behavior of people in this thread (who want a light that shows as soon as a car is in the blind spot) but it is there.

As for rear cross traffic, the car simply never sets itself up for a situation where it would back out from a 90 degree spot, as it backs in when it parks in those spots. In fact, I believe even in existing L4 cars, they rarely if ever back up, nor do they necessarily handle the end parking part at the depot.
 
Yes, I had the warning go off the other day when I purposely went around a car that ended up in the blind spot while I was moving back into the lane. He was stationary though. It was a pretty ordinary maneuver, at least for Brooklyn.
 
Note there is blind spot monitoring in the Tesla, it just doesn't alert or intervene until it determines a crash is likely. That is not the desired behavior of people in this thread (who want a light that shows as soon as a car is in the blind spot) but it is there.

As for rear cross traffic, the car simply never sets itself up for a situation where it would back out from a 90 degree spot, as it backs in when it parks in those spots. In fact, I believe even in existing L4 cars, they rarely if ever back up, nor do they necessarily handle the end parking part at the depot.
The cars sensor suite absolutely has blind spots.

Low & forward off-center it seems to have issues identifying lane cross events by adjacent lane car which are partially overlapping with your vehicle, to the front.

I have had multiple events where the car in NoA/AP did absolutely nothing, had no beeps/screen warnings/etc as a lane crosser nearly sent me into the guardrails. The car did not even attempt to slow down. It is clear the car did NOT see anything because a similar lane cross (or even non-crossing tire-touching-paint) event & say 1-4 car lengths forward, the car starts braking unnecessarily hard.

So its sort of worst of both words of over-caution in events where the human would not, and then a blind spot to clear&present danger that a human could not miss.
 
The cars sensor suite absolutely has blind spots.

Low & forward off-center it seems to have issues identifying lane cross events by adjacent lane car which are partially overlapping with your vehicle, to the front.

I have had multiple events where the car in NoA/AP did absolutely nothing, had no beeps/screen warnings/etc as a lane crosser nearly sent me into the guardrails. The car did not even attempt to slow down. It is clear the car did NOT see anything because a similar lane cross (or even non-crossing tire-touching-paint) event & say 1-4 car lengths forward, the car starts braking unnecessarily hard.

So its sort of worst of both words of over-caution in events where the human would not, and then a blind spot to clear&present danger that a human could not miss.
I'm not sure what that has to do with blind spot monitoring, which only monitors the blind spot in the rear for the human, it does nothing for blind spots in the front.

Also, NoA/AP has pretty much nothing to do with the current FSD stack, which is far more advanced and has not merged with NoA/AP yet. What you describe does not have to do with a blind spot either (at least one camera definitely sees the car in your situation), it is because the old stack only works with individual frames and does not handle objects that straddle two cameras very well. You can easily see this happen in the visualization when there are parked cars straddling two cameras, it will blink in and out. FSD Beta instead merges all the views and also has persistence between different frames in time.
 
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The cars sensor suite absolutely has blind spots.

It certainly does.

But none are remotely big enough to fit a whole other car into.

Basically it can't see anything in the space forward of the front fender cams and below the hoodline.

The B-pillar angled-forward cams and 3 front cams can see just fine above said hoodline.

You could sneak a skateboard in there (without the human standing on it) but not a car.