Profile: PRE-SAFE® Child

May 20, 2019


Networked child seat [6] with PRE-SAFE® functions


Before an impending crash, the seat belts of the child seat are preventively tensioned and side-mounted impact protection elements are extended if the triggering threshold of PRE-SAFE® is reached. Being more firmly fixed in the seat, the child is better protected from physical forces in a critical situation, e.g. during emergency braking. The loads acting on the child's head and neck areas during an impact are also reduced, as it is more firmly attached to the vehicle.

In detail

·         The spring of the belt tensioner is pretensioned by rotating the seat by 90° before lifting the child into it.

·         The side-mounted impact protection elements are mechanically pretensioned by manually pressing them into the seat, and they are out of the way when the seat is in use.

·         When triggered, the side impact protection elements minimise the gap between the door and the child seat.

·         When the PRE-SAFE® algorithm recognises that a crash may be impending, a radio signal is sent to the child seat. Within milliseconds the mechanical pretensioning of the five-point belt system and that of the side impact protection element facing door is electrically released by solenoid switches. The necessary power comes from a long-life battery integrated into the child seat.


Additional functions

·         Installation monitoring: Eight icons[7] on the seat and corresponding 3D animations in the media display signal correct installation.

·         Monitoring of vital signs: The temperature, pulse, breathing, state of wakefulness and sitting time of the child are monitored. During a journey, clearly understandable animations in the media display show the child's condition.

·         Baby Live video: When the car is stationary, e.g. at traffic lights, it is possible to briefly switch over to a live image from the child seat in the media display. To this end the child seat has a 12 volt onboard power supply via USB.

·         Mercedes me: Vital signs and live video information can also be sent to smartphones via Mercedes me - but only when the ignition is switched on.

What accident research says

·         A study published by insurance company accident researchers (UDV) in October 2018 found that almost one in two child seats are not correctly installed in the car. 48 percent of the 1042 children examined were not correctly secured in their child seats. The main causes were seat installation errors and incorrect belt fastening.

·         The aim of installation monitoring for the ESF child seat is to prevent such mistakes.


·         PRE-SAFE® vehicle sensors

·         Installation monitoring

·         Integrated sensors to measure the child's vital signs

·         Camera in the seat for video function and monitoring the child's condition

[6] From birth to 4 years / 40–105 cm / 0-18 kg; up to 15 months in reboard position.

[7] The icons show correct belt buckle fastening, PRE-SAFE® pretensioning, seat correctly rotated and engaged in position, belt tensioned, ISOFIX locking, supporting leg with floor contact, radio connection, power supply