The scan methods of FDM in the RP were analyzed in this passage,and algorithm of shuttling region was proposed;based on the area plots what the solid and support need to be filled,the algorithm of relative -distance optimizing was to be carried out to find its best filling order;in the end,dynamic simulation was done with the help of Microsoft Visual C++ 8.

The paper first analyses the difference between the cloudlet and its shadow in the satellite remote sensing image,investigates the relationship between the scanning region and the sun azimuth at the imaging time,and sets up three equations to calculate the height of cloudlet,and proposes the method for the initial location of scanning region.

The paper focused on the phenomenon of warp distortion and balling,simple analyzed the reasons for each other and then proposed a new scanning path generating algorithm,which is repeat scanning combined with subfield scanning.