According to the mathematical equations listed below, rotation angle can be

calculated precisely.

Date Calculate：

X1 Axis：δX1=R cos (δθ+θX1+θ0)-R cos (θX1+θ0)

X2 Axis：δX2=R cos (δθ+θX2+θ0)-R cos (θX2+θ0)

Y   Axis：δY   =R sin (δθ+θY+θ0)-R sin (θY+θ0)

δX1：X1 Axis relative movement (mm) ｝

δX2：X2 Axis relative movement (mm) ｝(movement driven by ball screw)

δY  ：Y Axis relative movement (mm)    ｝

θX1：Angle position of pivot on  X1 Axis ( ° )

θX2：Angle positoin of pivot on  X2 Axis ( ° )

θY  ：Angle position of pivot on  Y Axis ( ° )

θ0  ：platform angle before movement  ( ° )

δθ：rotation angle of platform  ( ° )

R：radius distance from platform center to center of rotation bearings