Tesla Model 3, Model S fail automatic braking system stress test: IIHS

The Tesla Model 3 didn’t
do well in the tests.
Hollis
Johnson/Business Insider

• Five cars with automatic braking systems were stress
  tested by research group the Insurance Institute for Highway
  Safety.
• The Tesla Model 3 and Model S performed the worst,
  behind a BMZ, a Volvo, and a Mercedes.
• They were required to drive toward a stationary item
  with their adaptive cruise controls turned off, and only
  automatic braking on.
• The two Teslas were the only cars which failed to stop
  in time, and hit the object.
• In other parts of the test, the Teslas performed
  better, and were even over-cautious when braking.

New tests of automatic braking systems in cars found some
worrying problems with the technology, and two Tesla models were
the worst performers.

Test carried out by research group the Insurance Institute for
Highway Safety (IIHS)  found that some braking systems may
not notice stopped vehicles, and could even steer cars into a
crash rather than away from it.

In a series of tests created by the Insurance Institute for
Highway Safety (IIHS),
published in a report on Tuesday,
five cars were set to drive at 31 mph toward a stationary
object with the adaptive cruise control turned off, but with
automatic braking on.

The five models tested were:

• A 2017 BMW 5-series with its “Driving Assistant Plus”
  function.
• A 2017 Mercedes-Benz E-Class with “Drive
  Pilot.”
• A 2018 Tesla Model 3 with “Autopilot.”
• A 2016 Model S with “Autopilot.”
• A 2018 Volvo S90 with “Pilot Assist.”

The stress test found that the Tesla Model 3 and Model S were the
only two models that didn’t stop in time.

Both cars had braked and lessened the impact of a crash, but
still hit the stationary item.

The Tesla Model
S.
Tesla

However, in a separate test with the adaptive cruise control
turned on, the IIHS found that the Tesla models decelerated
gradually and braked earlier than the other cars.

This occurred in a test simulating multiple cars driving in a
row, where all the cars suddenly had to stop.

In fact, the IIHS noted that the Model 3 was prone to what it
called “unnecessary or overly cautious braking.”

While travelling a distance of 180 miles, the car unexpectedly
slowed down 12 times, seven of which after spotting tree shadows
on the road, and the others for vehicles traveling toward it in
another lane or crossing the road far ahead.

Jessica Jermakian, a senior research engineer at IIHS, said: “The
braking events we observed didn’t create unsafe conditions
because the decelerations were mild and short enough that the
vehicle didn’t slow too much.

“However, unnecessary braking could pose crash risks in heavy
traffic, especially if it’s more forceful.

“Plus, drivers who feel that their car brakes erratically may
choose not to use adaptive cruise control” — which was turned off
in the first test that the Teslas failed — “and would miss out on
any safety benefit from the system.”

The Teslas performed the best when it came to staying within
their lanes on curves and hills, however.

Results
from the Insurance Institute for Highway Safety’s tests on
electronic driver assist systems, published in a report on August
7, 2018.

Insurance
Institute for Highway Safety

The IIHS in particular highlighted the
fatal crash of a Tesla Model X in March as evidence of the
shortcomings of driver assistance systems.

The car, which was driving while the semi-autonomous Autopilot
software was engaged, crashed into a highway barrier in Mountain
View, California, and caught fire. The driver, Walter Huang, died
after being taken to the hospital.

Tesla later released a statement saying that Huang must not
have been paying attention for the accident to take place,
“despite the car providing multiple warnings to do so.”

The episode, the
IIHS said, “demonstrates the operational limits of advanced
driver assistance systems and the perils of trusting them to do
all of the driving, even though they can’t.”