A flexible pressure sensor array for self-powered identity authentication during typing.

The keyboard, a staple tool for information entry and human-machine interaction, faces demands for enhanced information security due to evolving internet technologies. This study introduces a self-powered flexible intelligent keyboard (SFIK) that harnesses the giant magnetoelastic effect to convert the mechanical pressure from key presses into electrical signals. The sensor boasts a wide sensing range (35 to 600 kPa) and a rapid response time (∼300 ms), allowing it to record and recognize individual keystroke dynamics. Integrated with machine learning, this keyboard enables identity authentication through both fixed- and dynamic-text inputs. It accurately authenticates fixed passwords of eight characters with a 95.3% success rate and dynamic text from 14 sets of double keys with 100% accuracy. Given its capabilities, the SFIK offers promising applications in artificial intelligence, network security, and access control for computers and networks.