Best Practice

Replace the car key with your voice

Together with Brose, Reply's voice experts have developed a prototype that enables the secure unlocking of the car by voice control.

#unlock car
#voice biometrics
#vehicle security

"Please open the door" and one of the doors or the boot unlocks - thanks to biometric verification, there is no need to worry about unauthorized access.

The idea

Secure unlocking by voice command

Every driver knows the difficulty of unlocking their vehicle when both hands are full, for example with work bags or shopping. Unlocking by voice command is particularly suitable and helpful for this purpose – but the question arises: "What then stops any random person from accessing my car?" This is a justified concern that Reply's voice experts have addressed together with a special research team from automotive supplier Brose.


The solution

Voice biometrics for enhanced vehicle security

What we know from our cell phones' facial recognition or fingerprint sensors now also works with our voice. Experts from Reply and Brose have jointly developed a voice-controlled vehicle model that only executes voice commands if the user is recognized by the car as authorized. To do this, the system checks the biometric properties of our voice – our acoustic fingerprint. This guarantees security when the vehicle is opened by voice control.

How we did it

Voiceprints, microcontrollers and a digital twin

To unlock the car securely by voice control, the experts from Reply and Brose have implemented the following elements:

Voice verification

To distinguish authorized from unauthorized users, Aculab's Voisentry – a cloud-based provider – was used. The voiceprints of authorized users were stored on the provider's platform. Verification is performed on the basis of these voice samples using AI.

Development with digital twin

To speed up development and increase efficiency, Reply's voice team created a digital twin of the vehicle. After verification of the voice, this can be operated by voice control and simulate the functionality of the planned product.

Opening via actuator

In order to be able to open the doors or the trunk of the real car, the Brose research team built a vehicle model with a microcontroller and actuators. This model enables the idea to actually be used in reality.

The result

A prototype with future

The experts from Reply and Brose have succeeded in developing a promising model that makes it possible to unlock a car's doors securely by voice control – really a prototype with future. Indeed, plans are already underway to link the project to the electronics of a test vehicle in collaboration with a car manufacturer.




Brose is the fourth largest family-owned automotive supplier. Every second new car worldwide is equipped with at least one Brose product. The company's intelligent solutions for vehicle access and interior provide more comfort and flexibility. Innovative concepts for thermal management increase efficiency and contribute to environmental and climate protection. Brose's understanding of systems enables new functions in vehicles of all kinds - whether on four or two wheels. Including the Brose Sitech joint venture, the company employs 30,000 people at around 70 locations in 25 countries. In 2022, the Brose Group generated a turnover of around 7.5 billion euros.