Tests of automated driving systems show drivers shouldn't rely on them

Mercedes-Benz C-Class

Standard active safety system: Active Distance & Active Steering Assist

• ACC stops the C-Class from hitting a stationary car at up to 44mph, while AEB helps to avoid or mitigate an incident up to the top speed tested. 
• The driver is able to swerve to avoid a pothole; the system reactivates after this. 
• Hands-off warnings start early and are progressive. The car is brought to a controlled stop if they are ignored. 

Hands-off ACC warning timeline

Nissan Leaf

Standard active safety system: ProPilot

• ACC prevents the Leaf from hitting a stationary car below 38mph. AEB should assist at up to 56mph, but it didn't activate in the test we observed. 
• Lets the driver avoid a pothole, an assistance continues afterwards. 
• ProPilot is the quickest to provide a hands-off warning. If ignored, it soon brings the car to a controlled stop. 

Hands-off ACC warning timeline

Tesla Model S

Standard active safety system: Autopilot

• ACC stops the Model S from hitting a stationary car up to the top speed tested, bringing it to a gradual stop. 
• The system initially resists if the driver tries to swerve to avoid a pothole. The system deactivates when the driver applies torque to the steering wheel. 
• Hands-off warnings are the slowest to occur. However, if the warnings are ignored the hazard warning lights come on and the car is brought to a controlled stop. If this happens, the steering assistance can't be re-engaged for the rest of the trip. 

Hands-off ACC warning timeline

Toyota Corolla

Standard active safety system: Safety Sense

• ACC stops the car from hitting a stationary vehicle at up to 30mph; AEB assists up to the top speed tested. 
• The driver is able to steer around a pothole and the system resumes afterwards. 
• Visual and audible hands-off warnings are given quickly. If they're ignored, the system deactivates, but the car isn't brought to a stop. 

Hands-off ACC warning timeline

Volvo V60

Standard active safety system: Pilot Assist

• ACC doesn't respond to a stationary vehicle, but AEB does, providing assistance up to the top speed tested. 
• Lets the driver swerve to avoid a pothole and continues assisting afterwards. 
• Hands-off warnings start in good time and the system deactivates quickly if they're ignored. The car isn't brought to a halt though. 

Hands-off ACC warning timeline

Since the publication of these tests, Volvo has confirmed that it will remove any mention of 'semi-autonomous' from its marketing material.  

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