Radar bicycles and the million-dollar question

SAFER's lunch and networking seminar for the spring 2020 started of well! The first speakers of the year delivered an eventful seminar, even though the technology were not on its best behavior. Jacob Andrén, Aptiv and Jonas Andersson, RISE presented the SEBRA project. Linda Meiby, Scania went in depth on the subject of the challenges of human machine interaction. Attendants of the first SAFER lunch and networking seminar of the year were delighted with a fresh salad and first-class innovation as the speakers shared their respective topics. Magnus Granström, SAFER's director, were on site to start of the whole affair. After some technical difficulties Jacob and Jonas were ready to start.

The SEBRA project, or Sensor for Bicyclists impRoved Awareness, is simply explained a detection system to assist bicyclist. SEBRA is a SAFER collaboration between RISE, Aptiv and Liri, financed by FFI. The system is radar based and works with a haptic and visual HMI to communicate, both with the cyclist and the surrounding traffic. Radar being the most affordable and versatile system for this task, was a natural choice. Some of the systems functions include warnings. For instance; forward and rear collision warnings and blind spot warnings alert the rider to potential surrounding dangers.

A small-scale user testing has been implemented on the system. So far, the feedback has been a variety of positive and negative responses. Mostly surrounding signal interpretation and user experience. Interest to use the final product has been among the received comments and work, to evolve the system, continues.
Future studies will for instance include modeling of interaction between bikes and other road users. There is also an aspiration to work with smart helmets and V2X, amongst other topics, in the future.

At the time when Linda Meiby took the floor, most of the attendants of the seminar had finished their lunch. Maybe even glancing toward the direction of the coffee machine. But the general atmosphere of the room was eagerness to hear what she had to share.
Breaking it down to its very core HMI, or Human Machine Interaction, is essentially “rocket science” meeting psychology, according to Linda Meiby. The way the human brain preserves its surroundings has not yet adapted to the modern-day life, and especially not to modern autonomous vehicles (AV). In her work as a Technology Leader in HMI, Linda strives to resolve these challenges with increasing automation. To explain to the audience, she used examples concerning heavy AVs.

Linda explained something called “the cognitive sweet spot” in connection with AVs. The Cognitive sweet spot is where the human brain is at its uttermost efficiency and at its peak of alertness. Where the human is focused, quick to react and make calculated decisions. This sweet spot occurs when the balance of impressions is just right. Not too much as to overwhelm the brain, yet not to under stimulating as to cause it to shut down. This occurrence is usually not more than 20 minutes, and research is being conducted to formulate systems to cater to this.

Linda Meiby’s adduction promoted discussion, as the SAFER seminars so often do.
The audience learned that the personal preferences on how to interact with AVs differ greatly among users. The preferred interaction is very personal, voice control, touch screens, buttons, sensory control – many are the choices, but none so far are universally preferred.
Furthermore, the conversation was directed towards the correlation between the alertness of drivers, AVs and safety. Linda elucidated:
“The million-dollar question is: How do we engage the drivers of autonomous cars enough for it to be safe? We are still working on it.”.


Safer – Vehicle and Traffic Safety Centre

SAFER is the open innovation arena where researchers and expertise work together to create safe mobility. Our traffic safety approach covers people, vehicles and the infrastructure – and together we contribute to safer road transports and smarter, more sustainable cities.

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