A Semi-Scientific Ranking of Semi-Autonomous Features

Manufacturers are racing to arm their vehicles with enough cameras, radars, sensors, and tech to properly outthink man.
1. Automatic parking
Admit it: You suck at parallel parking. But when you activate automatic parking on some Fords and Nissans, you never again worry about lining up your wheels. Tesla takes it one step further: Stop the car within 33 feet of the space, get out, hit a button on the key fob, and watch the car park itself. 

2. Adaptive cruise control
Laser or radar systems monitor surrounding vehicles and adjust speed accordingly. Back in 2010, Audi’s A8 was the first to incorporate GPS data, which allowed the car to detect vehicles headed for exit ramps and slow down if necessary. Now traffic-jam functions are the norm: Cars can fully stop and accelerate again if the pause is less than three seconds. 
3. Blind-spot assist
Sensors in body panels can detect vehicles lurking in your blind spot. Early forms of the tech were first introduced in the Volvo S80 in 2007, and now nearly every manufacturer offers a range of them—from an alarm bell to an indicator light to an actual braking correction in the Infiniti Q70. The catch: Most don’t start looking until you’ve put on your blinker. 
4. Lane departure
In 2004, the Infiniti FX was the first U.S. vehicle to alert drivers when they started drifting out of their lane. Today, Bentley’s new Bentayga will gently guide the wheel back to center, while Mercedes-Benz’s E-Class and Infiniti’s QX30 have wheels that vibrate to give the driver a heads up—though poorly marked roads can cause the systems to fail. 
5. Hands-free driving
Tesla’s Model S comes with an “autopilot” mode—the most advanced hands-free system on the road, which employs radar, cameras, ultrasonic sensor, and GPS to steer the car. But is it too advanced? In May, a man using autopilot died in a crash; Tesla reportedly blamed its braking system, but the incident caused concern throughout the industry.