Abstract
This report focuses on a development of a 3-dimensional drag sensor. Three strain gauges and a nonmetal cylindrical material constitute the sensor. The strain gauges are put on the side of the cylindrical material at intervals of 2π/3 radians. The strain gauges detect the deformation of the cylindrical material. The output voltage of the gauges can be approximated by sinusoidal functions with a phase difference of 2π/3 radians. We show that the contact angle and the load are estimated by the approximated sinusoidal functions and measured output voltage.
