Optimised circuit design for precise bite force measurement using flexiforce sensors

The precise measurement of bite force is vital in dental diagnostics, particularly for evaluating tooth restorations, prosthetic interventions, and orthodontic treatments. This study presents the calibration and evaluation of the Flexiforce A301 sensor using optimised low-drive voltage circuits to extend its measurement range. Three circuit configurations, a voltage divider, a feedback resistor, and a feedback resistor with a capacitor were designed, simulated using LTspice, and experimentally validated. Results indicate that the configuration incorporating a feedback resistor provides superior linearity and stability, accurately measuring forces up to 100 kg, outperforming other configurations. This advancement enhances the reliability and range of bite force measurements, offering a robust foundation for high-force dental applications.