‘Intelligent blinker’ for night riders

Home Technologist Online ‘Intelligent blinker’ for night riders

In just three months, five electrical engineering students developed a prototype for a smart blinking wristband to help keep cyclists safe at night.

A cyclist wearing the smart wristband 'Intelligent blinker'

For cyclists in large cities, braving the traffic and dodging cars while changing lanes is difficult enough during the day, let alone at night. So five PhD students from École Polytechnique Fédérale de Lausanne (EPFL) took matters into their own hands, quite literally, and created a smart wristband that flashes when a cyclist reaches out the arm to indicate a lane change.

The invention – ‘Intelligent Blinker’ – was recognised at the Texas Instruments Analog Design Contest, a European competition held in Munich.

Running on solar energy

The principle of the bracelet is relatively simple. The device consists of an accelerometer and a magnetometer – a kind of compass – that can detect the position of the user’s arm. When the rider reaches out to the side, the accelerometer and magnetometer provide data to a microcontroller, which turns on a LED source.

“According to the habits of the rider, it’s possible to adjust the angle at which the LED starts flashing,” says Pietro Buccella, one of the students participating in the project. The bracelet is also equipped with small solar panels connected to a battery. It’s possible to run it only on solar energy. “We still equipped it with a USB port to enable recharging with a computer, if necessary,” says the student.

Gearing up for multi-function wristband

Currently measuring about five square centimetres, the circuit controlling the operation of the wristband is too bulky to be worn comfortably. But then again, the young scientists developed their invention in just three months.

In the near future, the wristband will be miniaturised to the size of a small watch. Energy consumption will also be reduced, and the wristband will be equipped with additional sensors. Improvements will be made by students as part of their Bachelor of Electrical Engineering degree. At least this is the intention of the inventors of the concept, who already see a future for their technology.

“Electronic wristbands are already very fashionable among athletes, whether to measure physical activity, calories burned or sleep quality,” says Buccella. “We could very well imagine combining our technology into these fitness tracking wristbands.”

Adapted from EPFL Mediacom’s Summer Series.



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