Advantages of fingerprint sensing in the car

For several years, car manufacturers have looked to the smartphone to provide a model for the development of an increasingly sophisticated user experience, particularly for the driver. Cars have followed the smartphone's lead by, for instance, providing a larger Centre Information Display (CID) screen offering higher resolution and fast, responsive capacitive touch sensing.

Now the automotive industry is looking to another feature of the smartphone's user interface, the fingerprint sensor, to enhance and modernise the driver's interface to functions in and even beyond the car. In fact this – and other forms of biometric authentication – appear to show great promise if implemented with sensitivity to user privacy and the limitations of the automotive operating environment. But the use cases of biometric authentication in the car look set to differ, perhaps surprisingly, from those of the smartphone.

Personalising the user experience
The obvious assumption about fingerprint sensing in the car is that it should be used as a convenient and secure replacement for the key both for providing access to the cabin and for starting the engine. In the smartphone, of course, fingerprint sensing performs this security function, barring access to any person other than the registered owner. In a car, however, fingerprint sensing is an unsatisfactory form of security in vehicles for two reasons.

The first is because of a difference in the usage model of a car from that of a smartphone. A car may be driven by people other than its registered owner. For instance, users of a valet parking service need to give the valet a means of starting the car. Equally, a driver who finds himself or herself incapacitated might want a suitably insured person to drive the vehicle on their behalf. A fingerprint sensor, then, can never entirely replace a key.

There is a security as well as a convenience reason why a fingerprint sensor cannot be the sole means of securing the car. This is because every fingerprint sensing technology in existence has a 'false acceptance rate'. Occasionally, every fingerprint sensor will wrongly identify a stranger's fingerprint as that of the registered user. Even the smallest risk that a potential car thief could steal this expensive asset simply by pressing a fingerprint sensor is too great for car manufacturers to accept. For security reasons, therefore, fingerprint sensing would always need to be backed by a supplementary form of access control. Conventional RF-operated keys, then, are not about to be superseded by fingerprint sensors on the door handle or Start button.

Fingerprint sensing does, however, enable two far-reaching improvements to the driver's user experience: personalisation, and payment authentication.

In a car with two or more regular drivers, the fingerprint sensor may identify who is driving, allowing the car's operations to be configured to that driver's preferred settings. This affects convenience settings such as the position and height of the driver's seat, mirrors and steering wheel, comfort settings such as the temperature and direction of the cabin air stream and vents, and entertainment settings, such as Bluetooth pairing with the driver's phone, the choice of favourite radio stations, the sound balance in the audio system, and even the appearance and menu configuration of the CID.

Personalisation of the user interface strengthens the emotional bond between owners and their vehicle, making it uniquely theirs. In an important way it also improves the driver's ability to make use of the sophisticated features and functions in a car, many of which in today's cars are hidden behind multi-layered menu structures and complex sets of commands. Research has shown that for every step added to a user interface, 10% of the users drop out. Personalisation via a fingerprint sensor reduces the number of steps to one or even none for many aspects of the user interface, thus making valuable features much more readily accessible to users.