Let me see. You want to create a plot from 3 independent variables, but one of them is always zero. So there is no information content in that dimension. You might as well have said there are 5 other variables, each of which is also zero. And so?
The rest of your data is massively replicated, so you have only 9 distinct points, at these combinations.
unique(AD,'rows')
ans =
500 30
500 60
500 90
1000 30
1000 60
1000 90
1500 30
1500 60
1500 90
Sorry, but what? There is nothing that can be interpreted to represent a surface in those points.
