Executive Summary : | The project aims to create a silk torsion pendulum sensor with the highest sensitivity of 100 zepto-Newton-meter (1 zeptoNm = 10^-21 Nm). Despite being an ancient device since the 18th century, reaching zNm sensitivity has been challenging. The project aims to overcome five challenges: developing critical components, calibrating the sensor with 100 zNm precision, developing a rapid detection scheme for measuring sub-micro radian angle, reducing noise floor, and building a battery-operated zNm torsion sensor capable of providing torque readings round-the-clock 24x7. The team extracts sub-500 nm diameter silk fiber as an ultrasensitive torsion spring, fabricates an ultrathin microgram mirror, creates an ultrahigh vacuum chamber, uses radiation pressure for calibration, and develops a real-time measurement technique for torque. The silk-sensor will continuously measure torque 24x7 for over a year, outperforming conventional high-end counterparts by 10 to 100 times in sensitivity and speed of measurement. A prototype zNm silk sensor will be developed, capable of operating on battery and storing and transmitting time-resolved torque for standalone remote operation. The zepto-Newton-meter sensor will be used to record micro-seismic activities before, during, and after an earthquake. |