Two-axis pointing mechanism for earth observation system using heterodyne interferometry positioning sensor

The 2-Axis pointing mechanism which we developed is designed fbr earth observation system. This pointing mechanism is expected to work on the geostationary orbit with high resolution compare with former one. To achieve high resolution,we adopted optical heterodyne technique to minor angle detecting sensor instead of rotary encoder The angle of the mirror is calculated from the distance between mirror base and a certain point of reverse side of the miry lad. For mirror driving mechanism, we adopted a crank mechanism because a pointing mechanism working on the geostationary orbit is not necessary to rotate whole angle. We can get about 1:10 reduction ratio with a crank mechanism in addition to the reduction gear attached to the motor shaft. We have made experimental model and validated its performance.