I am wondering what is the best grid size when creating VRA missions in Pix4D Fields for the DJI Agras T50 drone? Thinking logically, excluding other flight parameters, the only thing that makes sense to me is that the spread width should be the same or approximately the same or even bigger as the size of the grid in the VRA mission?
Does the size of the grid affect the effectiveness of the VRA mission with the Agras T50, for example if I set the size of the grid to 4m, is that perhaps too small?
What grid size is optimal so that the Agras T50 can physically and accurately change the spray/spread rate when we do VRA fertilization with mineral fertilizers?
Beside that, when I am importing prescription map to DJI drone from Pix4D Fields it asks me to choose Resample option. It gives me two options Max value and Average value. Can anyone explain me what does that mean,which option is better to be agronomically useful?
Thanks in advance,
Rados
Hi,
Thank you for your comment. Based on our experience, 4 to 5 meters is the distance at which Agras react to the rate. The minimum that DJI accepts is a 1-meter grid, which is the minimum that can be exported from PIX4Dfields.
We would still suggest a 1- or 2-meter grid for fertilizer, and the drone will react in more meters.
Regarding the import of the prescription, it is advised to choose the maximum value, which means the drone will apply the maximum rate when reading two cells with different rates.
If you choose average, it will apply the average of the two cells that the drone is passing over.
Jose, thank you for your answer.
I am not sure I completely understand your answer. If Agras needs 4-5 meters to react to rate is the 1 or 2 m grid to small for the Agras to react in time and apply wanted fertilizer in area? Of course its not acceptable to have to many zones, in most cases I have 3 or 5 zones for VRA missions.
Thanks!
We suggest testing your own configuration and finding the optimal cell sizes. The drone will always need a few meters to adjust the rate.
When performing VRA, use a coarser prescription to ensure the drone operates properly. You can set this under Zone detail while creating the Operation.
It's clearer to me now, thank you very much for the detailed answer.
Best regards,
Rados
