Invisible Biometric Lock: Building the Smart Door Handle

Architect Ramesh is known for blending contemporary residential design with classical accents. For his own bungalow in Bangalore he imagined a completely keyless way of living: no keys for the stilt parking entrance, the main ground-floor door, or any of the bedroom and walk-in wardrobe doors. The house is entered through a grand 12-foot door with traditional design elements.

The brief

Ramesh invited us to consult on the automation design for his new bungalow after seeing our earlier projects. He wanted a complete system: energy-efficient lighting, mood and scene-based lighting, motorised window treatments to manage sunlight, whole-home Wi-Fi, multi-room audio and automated irrigation.

The most demanding request was an invisible biometric lock for the main entrance. He felt that standard biometric scanners take away from the beauty of a door like this.

Two ways biometric locks are normally built

Most biometric door systems follow one of two layouts. The images below show typical components for illustration.

Option 1: One integrated unit

The scanner and the lock are a single device. It works on simple "unlock when the finger is recognised" logic.

Option 2: Separate scanner, lock and controller

The scanner and the lock are separate parts managed by a central controller, which allows real access rules:

• One finger can unlock the main door, a bedroom and a wardrobe together
• A housekeeper's finger can open only the main entrance
• A "lockdown" scan can disable all other biometric access until a primary user resets the system

Option 2 is far more flexible. But the scanner still had to be mounted somewhere visible, and that was exactly what Ramesh wanted to avoid.

Hiding the scanner in the handle

After extensive research and brainstorming, we found a way to build a compact fingerprint scanner directly into the door handle. The sensor has a very small footprint, so it is almost unnoticeable.

We also offered to conceal it completely behind the handle. Ramesh preferred it on the front of the handle for better ergonomics.

In the end we delivered the invisible biometric solution along with elegant automation keypads. Mood lighting was configured across all the living areas, with lighting scenes built around chandeliers and spike lights for the plants in the living mezzanine areas.

See it in action

What came next