Patent ID: 8899110

Claim:
A pedaling motion measuring device comprising: a measurement body unit that has second sensor units arranged on a bicycle provided with a crank member having a right and left crank arms each connected between a hanger shaft and each of a pair of pedals, each of the pedals rotating with respect to a pedal shaft parallel to the hanger shaft, each of the crank arms angled with respect to the pedal shaft and the hanger shaft, the second sensor units sensing magnitude and direction of a force applied to each of the right and left crank arms; a second work calculation unit that calculates user's work provided to the crank member by the user, based on the magnitude and direction of the force applied to each of the right and left crank arms and sensed by the second sensor units, wherein the second sensor units each include an angle sensor measuring angle positions of corresponding one of the crank arms rotated by an operation of the user, and a plurality of force sensors each measuring a force applied to the crank member based on a distortion of the crank member, the second sensor units outputting information on the force applied to the crank member in association with the angle positions of the crank arms, wherein the second work calculation unit calculates magnitude and direction of the force applied to the crank member by comparing reference distortion information previously stored as an output value of each of the force sensors when a certain force is applied from a certain direction to each of the crank arms at each of the angle positions against an output value from each of the force sensors.