Orbit Logic has been using STK* for visualization of our mission planning and scheduling solutions since the company was founded in 2000. This year we have been moving towards web-based and multi-user solutions. In this environment we still have some users who use the analysis powers of STK, but others who merely want to see visualization of their plans. After a trade study, we chose Cesium to provide a light-weight, low cost and web-compatible visualization solution.

Within our satellite imagery collection planning solutions we use 3D map visualization to show the satellites and their ground track; field of regard and constraints for the sensor; the camera boresight path and off-nadir guidelines; collection orders and labels that are color-coded by status; and terrain and forecasted cloud cover. Within the map, the user can zoom in or out, manipulate what is displayed (or not), change colors, adjust the viewpoint, and animate the plan. We employ this Cesium visualization for collection planning from space-to-ground, space-to-space, and ground-to-space. The 3D visualization provides insight that Gantt charts and tables do not fully realize.

Drawing on our extensive experience with STK and Google Earth, we designed our Cesium-based solution to visualize satellites and display various cones (field of regard, field of view, sun glint keepout, antenna blockages, etc.) based on calculations we made ourselves. The open source nature of Cesium was helpful when we were looking for a way to show umbra/penumbra. We found an example with day/night on one of the Cesium forums. Since we were interested in twilight as well, we extended that example and posted our own solution to make it available for the Cesium community.

*Systems Tool Kit, a modeling environment for complex systems made by AGI, the company that started Cesium.