DRCC emergency stop at 70mph

I've generally gotten used to trusting the car to maintain distance and slow down autonomously with DRCC.

However today I'm not sure I trust it completely.

I had it set at 70mph, with the shortest gap out of the three gap settings. An accident up ahead with police cars, which I could see several cars ahead, and the cars in all four lanes slowed down very abruptly.

The Prius only looks at the car in front, and decided to brake so late, that I decided to apply the foot brake myself to come to a stop. I didn't feel like it was going to stop safely without my intervention, which made me afraid.

I remember the red brake sign coming up on the dashboard, and the tyres squealing as it attempted to stop.

It made me think about human vision by the driver, where we can see way up ahead vs the radar on the car which can only see the car the car in front. A friend in a BMW says they sometimes have experienced this when using radar cruise.

Anyone else had similar experience?



Posted via the PriusChat mobile app.

 

From my UK manual on DRCC,
"Before using dynamic radar cruise control with full-speed range
Driving safely is the sole responsibility of the driver. Do not rely solely on the
system, and drive safely by always paying careful attention to your surroundings.
The dynamic radar cruise control with full-speed range provides driving
assistance to reduce the driver’s burden. However, there are limitations to
the assistance provided.
Even when the system is functioning normally, the condition of the preceding
vehicle as detected by the system may differ from the condition
observed by the driver. Therefore, the driver must always remain alert,
assess the danger of each situation and drive safely. Relying on this system
or assuming the system ensures safety while driving can lead to an accident,
resulting in death or serious injury.
■Cautions regarding the driving assist systems
Observe the following precautions, as there are limitations to the assistance
provided by the system.
Failure to do so may cause an accident resulting in death or serious injury.
●Assisting the driver to measure following distance
The dynamic radar cruise control with full-speed range is only intended to
help the driver in determining the following distance between the driver’s
own vehicle and a designated vehicle traveling ahead. It is not a mechanism
that allows careless or inattentive driving, and it is not a system that
can assist the driver in low-visibility conditions. It is still necessary for
driver to pay close attention to the vehicle’s surroundings.
●Assisting the driver to judge proper following distance
The dynamic radar cruise control with full-speed range determines
whether the following distance between the driver’s own vehicle and a
designated vehicle traveling ahead is appropriate or not. It is not capable
of making any other type of judgement. Therefore, it is absolutely necessary
for the driver to remain vigilant and to determine whether or not there
is a possibility of danger in any given situation.
●Assisting the driver to operate the vehicle
The dynamic radar cruise control with full-speed range has no capability to
prevent or avoid a collision with a vehicle traveling ahead. Therefore, if
there is ever any danger, the driver must take immediate and direct control
of the vehicle and act appropriately in order to ensure the safety of all
involved."

Then, the disclaimers surrounding, Toyota Safety Sense,
"Toyota Safety Sense∗
◆ PCS (Pre-Crash Safety system)
◆ LDA (Lane Departure Alert with steering control)∗
◆ Automatic High Beam∗
◆ RSA (Road Sign Assist)∗
◆ Dynamic radar cruise control with full-speed range∗
◆ Dynamic radar cruise control∗
The Toyota Safety Sense consists of the following drive assist
systems and contributes to a safe and comfortable driving experience:
WARNING
■Toyota Safety Sense
The Toyota Safety Sense is designed to operate under the assumption that
the driver will drive safely, and is designed to help reduce the impact to the
occupants and the vehicle in the case of a collision or assist the driver in
normal driving conditions.
As there is a limit to the degree of recognition accuracy and control performance
that this system can provide, do not overly rely on this system. The
driver is always responsible for paying attention to the vehicle’s surroundings
and driving safely."

Thanks for the reminder that it's a driver assist feature. I guess I got lulled into a false sense of security because I was reading about others using it in traffic and my initial experience where it did seem more advanced than it actually is in reality. A reality check as you point out.

 

That's interesting to hear your usage of the system. I tried 1 bar today simply because with 2 or 3 bars, I found that other cars were pulling into the gap very frequently.

 

Well, with so many electronics and driver 'aids' in new vehicles today, and given that each brand's systems may work differently than another brand's system, maybe car companies/dealers should be offering short courses to 'properly' educate new owners on what the system can do, and what it can't do, and how best to use it in all different scenarios? Just like those test environments that Toyota set up for journalists to try the new Safety Sense features away from public roads.

Yes of course, there is a several hundred page online manual available post purchase, but I'm starting to think that the option of a practical course at the dealership would be a useful one.

 

To be clear, what I meant was that practical courses would be developed by Toyota themselves, but administered by the dealer.

 

Yes of course, you are right the manuals are available to anyone. However, I suspect many owners are not passionate enough to be on PC and I would hazard a guess that they wouldn't bother to read the online manual before purchase. Hence, I stated post purchase as the behaviour of the masses.

 

ROFL. Yes, at my local Toyota dealer, the sales person insisted the new Prius was not available with 15 inch wheels, despite the model in the showroom that we were staring at, having 15 inch wheels. Needless to say, I didn't buy the car through them.