Unfortunately there are so many people who have joined just to put down Tesla that it has become difficult to trust that what they are saying is true. Why did you join?
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General info about stopping distances and killing people via ignorance of it.
If you are 80 feet (5 cars) behind me when I was going 117 fps (80mph), I would think you were a drunk or an idiot.
You should be at LEAST 200 feet at that speed. Seriously. Just the different in stopping distances between cars makes sub 1 second following something done by fools. The stopping distance in good conditions at 70mph is 172 feet in an X. Sports cars stop in under 130 feet at 70mph with stock tires.
Somebody with good reaction time and 2 foot driving is a 1/4 second to brake lights in cars. Normal people are 1/2 second with one foot driving. Distracted is easily past 1 second. And you gave yourself 0.7 seconds? Even the TACC can't actually make up the difference between car models when using 5 cars/80mph. If a vette nails it's brakes in front of you, and the car instantly goes max brakes, that 80 feet at 80mph will be consumed by the difference in stopping distances.
In any case, following distance should always be measured in time, not distance. Obviously following distance changes with speed.
This is naturally assuming public roads. Closed course? Rubbing is racing.
If you are 80 feet (5 cars) behind me when I was going 117 fps (80mph), I would think you were a drunk or an idiot.
You should be at LEAST 200 feet at that speed. Seriously. Just the different in stopping distances between cars makes sub 1 second following something done by fools. The stopping distance in good conditions at 70mph is 172 feet in an X. Sports cars stop in under 130 feet at 70mph with stock tires.
Somebody with good reaction time and 2 foot driving is a 1/4 second to brake lights in cars. Normal people are 1/2 second with one foot driving. Distracted is easily past 1 second. And you gave yourself 0.7 seconds? Even the TACC can't actually make up the difference between car models when using 5 cars/80mph. If a vette nails it's brakes in front of you, and the car instantly goes max brakes, that 80 feet at 80mph will be consumed by the difference in stopping distances.
In any case, following distance should always be measured in time, not distance. Obviously following distance changes with speed.
This is naturally assuming public roads. Closed course? Rubbing is racing.
The general rule is 3 seconds. You need 3 seconds between you and the car in front to account for reaction time. 70 mph is about 103 feet/sec. That means you need to be back about 309'. As AEB gets better it will become safer to follow closer but right now the 3 second rule is still a good one. Two seconds is pushing it and means you better be very vigilant. All of this assumes your car and the car you are following have the same braking distances.
Your story doesn't make sense. You can't set autopilot to 80mph unless 1) you're already driving 80mph when you engage it or 2) the speed limit is 80mph, or 3) you set a positive relative offset (for example +10mph and the speed limit is 70mph) while you are driving slower than 80mph. If 3), how is setting a positive offset being cautious? In any case, your second claim is even more suspect. How could your car accelerate to 80mph if you're already driving 80mph? If you were driving slower than 80mph when the incident occurred why would the car wait until that moment to accelerate to 80mph? Or if you meant it was slowly accelerating the whole time, how long is it taking your X to reach 80mph on autopilot? I don't understand how your car could "continue to accelerate" to 80mph when this incident occurred.
I must say that I am a bit surprised at the scorn some folks heap in this forum on anyone that dares criticize anything Tesla. I think this discourages some from sharing their concerns and experiences and diminishes the value of learning more about the dynamics or quirks of these amazing cars.
I am curious about the failure of adaptive cruise control in this case. The situation described does not really apply to beta auto steer but rather to a technology that has been out for a long time. Most cars with adaptive cruise would sense the car slowing down ahead and adjust the speed accordingly.
My previous Audi SQ5 would beep if I was not braking in response to the car in front of me slowing down rapidly, and then apply the brakes to slow me down if I did not react fast enough. Great system except when someone slowed to turn right off the road and I was slipping by them on the left. This was not even with cruise on and simply a safety feature of that car. With cruise on, it would adjust the distance automatically based on speed and brake hard if the car in front of me did so.
So far my MX has not slowed me down when I have been distracted and someone braked in front of me suddenly (cruise and auto steer off). I wonder if this is even a feature or if it has softer settings than in the Audi. The adaptive cruise in my car has worked well however and adjusted the distance flawlessly on the highway and in stop and go traffic.
So some questions here:
1. Does the MX brake if the car in front slows suddenly but your cruise and AP are not activated?
2. Is the distance setting of 5 mean 5 car lengths at any speed (fixed distance) or is it a 5 second gap at whatever speed you are going? Or something more arcane?
3. Is it possible that the sensors were dirty on Micquing's car and would this make a difference?
4. Is there a glitch in the algorithms for detection of cars slowing ahead and has anyone else had this problem?
S
I am curious about the failure of adaptive cruise control in this case. The situation described does not really apply to beta auto steer but rather to a technology that has been out for a long time. Most cars with adaptive cruise would sense the car slowing down ahead and adjust the speed accordingly.
My previous Audi SQ5 would beep if I was not braking in response to the car in front of me slowing down rapidly, and then apply the brakes to slow me down if I did not react fast enough. Great system except when someone slowed to turn right off the road and I was slipping by them on the left. This was not even with cruise on and simply a safety feature of that car. With cruise on, it would adjust the distance automatically based on speed and brake hard if the car in front of me did so.
So far my MX has not slowed me down when I have been distracted and someone braked in front of me suddenly (cruise and auto steer off). I wonder if this is even a feature or if it has softer settings than in the Audi. The adaptive cruise in my car has worked well however and adjusted the distance flawlessly on the highway and in stop and go traffic.
So some questions here:
1. Does the MX brake if the car in front slows suddenly but your cruise and AP are not activated?
2. Is the distance setting of 5 mean 5 car lengths at any speed (fixed distance) or is it a 5 second gap at whatever speed you are going? Or something more arcane?
3. Is it possible that the sensors were dirty on Micquing's car and would this make a difference?
4. Is there a glitch in the algorithms for detection of cars slowing ahead and has anyone else had this problem?
S
On a divided highway you can set autopilot all the way up to 90mph, regardless of speed limit. It only restricts the speed if you are on a non-divided highway, and then it's 5mph over the limit.
Don't forget that a setting of "5" on the following distance doesn't necessarily mean 5 car lengths, just like 2 doesn't mean 2 car lengths. It varies by your speed, try it out.
Here is my Model X
Attachments
@Epymiam - It's not scorn, it's skepticism. Many of us here are also TSLA investors and it's been an annoying few months with constant false accusations/stories of Tesla problems which have the unfortunate affect of affecting the stock price and tarnishing the brand in the media. An accusation of unintended acceleration is very serious. As an experienced Tesla owner, I just don't buy this story at face value. It's either made up or the OP is leaving out/changing important details. To answer your questions:
1) yes
2) it's relative scale where follow distance varies with speed at each setting.
3) no. The car (annoyingly) reports sensor errors in real time.
4) no. I have a follow setting of "3" and have had zero issues with regular highway traffic and thousands of miles of autopilot driving. The only time there is some risk is if the car in front of you panic brakes but in many or most situations the driver might not fare any better if autopilot were off.
1) yes
2) it's relative scale where follow distance varies with speed at each setting.
3) no. The car (annoyingly) reports sensor errors in real time.
4) no. I have a follow setting of "3" and have had zero issues with regular highway traffic and thousands of miles of autopilot driving. The only time there is some risk is if the car in front of you panic brakes but in many or most situations the driver might not fare any better if autopilot were off.
FYI, 5 cars distance is not the stopping distance, it's the adaptive driving distance between your car and the car in front of you, and keep that distance while driving. Front car slows, your car slows automatically and vice versa
Ryan MF
Member
All the other systems (MBz, etc) that have been tested to perform worse do not say anything about being in test development.
Yes, but to set the speed you actually have to be traveling at that speed or use a positive offset or that has to be the posted speed limit. There is no knob or number pad or other interface option with which to "set" the autopilot speed to be 90mph.
mspohr
Well-Known Member
I just returned from a 2200 mile trip across NV and ID. Most of the driving on AP at 80 or 85. AP performed flawlessly, slowing smoothly behind traffic, changing lanes and no false exits.
Something is fishy about this story.
Something is fishy about this story.
I am relieved to see that you are located in Washington DC and not in my area because I do not want to be driving on the freeway at 70 and be followed by a Tesla owner who has their TACC distance set at 2. That is far too close. If the car in front of you had to make an emergency stop, by the time you or your TACC could react your frunk would be compressed into the trunk of the car in front of you.
Unintended acceleration is very serious, that's why my wife reported the incident immediately, hoping Tesla would look into it. As a MX owner, the purpose of my post is to share my experience and caution MX owner when using AP. After two years delay in delivering Model X, I feel like Tesla still rushes MX to the market. My MX was recalled for the 3rd row seat after only a month delivery; Last week, glass bubbles appear in the roof window and needs to be replaced; Delivery specialists over promise the MX features due to lack of training... As a Tesla investor myself, Tesla is a great company, but seems it has too many things on the plate at the same time: Model 3 announcement and Solar City (I'm also a Solar City customer)bid. Maybe Tesla should really focus on setting the right expectations to the clients and deliver solid product consistently.
That's not entirely true. You can set the speed to be your speed, and then you can full press the tacc stalk up several times to increase the speed setting by 5mph each time. If you're going 65 it only takes 3 full presses up to reach 80.
ZeroDarkSilver
HEPA cleaning your atmosphere, you're welcome
I've had AP active on my P85D since it was first introduced. I have put over 20k miles on the car since then and use AP fairly often. When the feature first became active, like lots of other owners, I did a few stupid things with it (like treat it as if it were an autonomous car). Since then, I use AP as it is intended and I've NEVER had a problem. That doesn't mean that AP works perfectly, it just means that I am always ready to take total control of the vehicle and I'm always aware of what AP is doing. I don't let it get me so far into a situation that I can't recover.
It's actually fairly simple to ensure that AP doesn't turn into a problem but people want to misuse the system.
It's actually fairly simple to ensure that AP doesn't turn into a problem but people want to misuse the system.
stopcrazypp
Well-Known Member
It is not just "anyone". A new member with little post history starting a new thread that heaps on non-constructive criticism (rather than suggesting ways for improvement, or asking about ways to avoid a similar situation, it suggests Tesla should have not released the feature at all) raises alarm bells. In this thread, we already have two known Tesla/TSLA naysayers chiming in also. It would be completely different if the comment was written differently and from a well known member.
Note: I'm not saying the OP is not an owner, but that he just happened to fit a profile that draws suspicion.
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