Page 15 - EngineerIt June 2021

AUTOMOTIVE ELECTRONICS

Emerging automotive in-cabin sensing

solutions for safety and comfort

By Andreas Pellkofer, product applications engineer and Gopal Karnam, system architect

utomotive cabin sensing is a rapidly evolving area with a increasing brand recognition and ensure customer loyalty. The
range of applications, using a combination of sensors and ever-increasing expectations of customers is putting an onus
Aintelligent algorithms. Today there are two key aspects on OEMs to add features that offer this enhanced experience.
driving the development of in-cabin sensing technologies. Personalisation and advanced human machine interface (HMI)
Firstly, regulations to improve occupant safety are being concepts (intuitive vehicles) are becoming key components
realised. Both Euro NCAP standards and European Commission of the user experience. OEMs can strengthen their brands by
(EC) regulations mandate the use of driver monitoring systems implementing unique comfort features. These could be automatic
(DMS) by 2022, and the U.S. National Transportation Safety climate control or ambient light adjustment based on the driver’s
Board (NTSB) recommends DMS in semi-autonomous cars. A mood and mental condition. Touch-free HMI systems allow driver
hands on/off detection (HOD) system is already required in 2021 interaction without requiring drivers to move their hands from the
to meet UN legislation (R79) for lane keeping assist systems steering wheel. Along with voice-operated systems, more precise
(LKAS). Also, child presence detection systems will become DMS using eye-tracking technologies continue to close the
mandatory in the U.S. by 2022. With this forthcoming legislation, gap with traditional touch-based interfaces. Differentiation and
DMS and occupant sensing capabilities will become a standard customer loyalty drive a need for an enhanced user experience.
feature of L2+ and above driving assist platforms.
The second key aspect is comfort enhancement for Applications
passengers — for example, through emotional sensing. OEMs A wide range of applications is covered by in-cabin sensing.
have detected that this is a differentiation factor and will use Figures 1 and 2 show application examples.
leading-edge innovation technologies to address it. Driver monitoring addresses the legislation requirements,
with features like HOD systems, and is becoming a mandatory
How DMS can reduce EU traffic fatalities solution deployed as a standard in future cars.
Safety Vital sign monitoring is also an emerging feature addressing
The European Transport Safety Council (ETSC) has calculated not only health-conscious drivers but also the aging population
that 51 people per million inhabitants in the EU were killed in road trends by monitoring the driver’s health, stress level, well-being
accidents in 2019, with 95% of the cases caused by a human and fitness to operate the vehicle.
factor: driver error, distraction, drowsiness, stress or fatigue. Biometric authentication not only provides support for that
1
The European Commission has announced a major package of personalised experience, such as seat and steering wheel
transport safety initiatives with the “target of a 50 per cent cut in position and preferred infotainment setup, but also provides
road deaths and serious injuries by 2030, with Vision Zero the security with the ability to authenticate the driver of the vehicle.
aim by 2050.” 2 Another vital safety application is occupant sensing. This
DMS today already support other advanced driver assistance
systems (ADAS). As an example, an LKAS is usually combined
with an HOD system to detect the hands of the driver on the
steering wheel. The system informs the driver to take back control
when required. In addition, DMS offers new features to detect the
driver’s health and ensure adequate attention levels.
The introduction of vital sign monitoring (VSM) technology,
such as electro-cardiography (ECG) or electro-dermal activity
(EDA → skin impedance), offers the ability to sense the driver’s
health and stress level in order to avoid potential issues before
they even arise. For example, if the VSM system detects the
driver is unable to control the car due to drowsiness or fatigue,
ADAS can bring the car to a safe state (slow down, steer to an
emergency lane, or stop the car).

Comfort
Ensuring an excellent driver and passenger experience is
more critical than ever. It offers the opportunity to innovate, Figure 1: Cabin sensor application examples.

EngineerIT | June 2021 | 13