Target operation safety airspace planning method based on space-time grid

The invention provides a target operation safety airspace planning method based on a space-time grid. The method comprises the following steps: step 1, dividing the whole space and time; step 2, dividing an airspace needing to be analyzed and calculated from a geographic space, and dividing levels of the airspace according to the space; step 3, analyzing fixed unavailable airspaces in the airspaces, and dividing levels of the airspaces according to the space; 4, analyzing a dynamic change unavailable airspace in the airspace, and dividing levels of the airspace according to the space; step 5, calculating the time when the target arrives at each space subdivision grid; step 6, associating a time vector for each element in the set; 7, expanding the elements in the time vector associated with the grid elements; step 8, calculating an available airspace grid set; step 9, calculating a security interval grid; and step 10, calculating an actual available airspace of the dynamic target in a preset range. According t