Gazebo simulation of an autonomous rover

We are currently building an autonomous rover that is designed to travel trough a farm or field, this rover will use a camera for image processing, and will detect weeds or unwanted crops. It will then only spray pesticides on the weeds or unwanted crops. What i need is a simulation of this robot on gazebo, we have the cad designs or solidworks assembly for our rover, the simulation must take place in a farm land, around 28x28 meters in size, this rover should do a mapping mission, where it will scan every bit of the field. In this field, there are 4 parameters, healthy crops; which we will not spray, the rover should just keep moving ignoring the crop, weed/unwanted crops; the rover will keep moving but it will spray pesticides on it, obstacles; such as a boulder or a tree, the rover needs to leave its formation to go around the obstacles and get back to its formation-mission line and keep on moving. and finaly, ditches; as it is a farm land we need to put in 5-6 ditches in the field, the rover will get past it, but we need to show that there are ditches and the rover needs to either move on a 3d field, or we can just do a 2d field and it will just slow down when its on top of the ditches. This is it, i need this project due to 28th of june, 2021, I require the algorithm, and a simulation video showing each step. Duration does not matter as long as it does the job. No editing required.