Patent ID: 11940303
Assignee: SONY GROUP CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 12:
13. A position detection method comprising:
calculating a reference position of a moving body on a basis of a first signal and a second signal, the first signal being detected from a first track provided on the moving body and having a scale of predetermined cycles, and the second signal being detected from a second track provided on the moving body and having a scale of cycles less than the predetermined cycles;
specifying a cycle corresponding to the reference position of the moving body among the scale of cycles of the first track on a basis of the reference position;
calculating an interpolation angle of the moving body in the specified cycle on a basis of the first signal;
calculating an absolute position of the moving body on a basis of a combination of the specified cycle and the interpolation angle;
detecting a position deviation occurs between the reference position and the absolute position on a basis of a difference between the reference position and the absolute position being greater than a predetermined value set based on a total number of the predetermined cycles of the first track;
determining, based on the detected position deviation, a total number of cycles included in the difference between the reference position and the absolute position; and
calculating a corrected absolute position,
wherein the calculation of the corrected absolute position includes subtracting, from the absolute position, the determined total number of cycles included in the difference between the reference position and the absolute position,
wherein the total number of cycles included in the difference between the reference position and the absolute position is determined by rounding a value obtained by dividing the difference between the reference position and the absolute position by a number of degrees included in a cycle in the first track, and
wherein the corrected absolute position is determined by subtracting from the absolute position a value obtained by multiplying the total number of cycles by the number of degrees included in the cycle in the first track.