How to set grid_bins and resolution in the RBFs representation?

[PencilAndBike]

I did the cart-pole and mountain car experiments. Both of them perform badly using RBFs representation when the variable grid_bins are set. But they could get a good result when grid_bins are none which means RBFs centers are chosen uniform-randomly and resolution are set to 10 to 20, but still perform badly when resolution are set too small. I don't know how to choose these parameters so that experiments can be sure to perform well. Thanks a lot.