I guess blurring is a hopeless way to make trackable gradients for your robot experiments. You need something like this:
This is drawn with pattern brush which has a linear 3-stop gradient white-black-white. The screenshot is from Affinity Designer which allows any PNG image to be used as a brush. The curve can be an arbitary path, you only apply the brush ...
IF all the objects have the same Gradient applied to them..
Simply select all the objects and make any adjustments you wish in the Gradient Panel.
Common gradients can be changed in unison by merely selecting the objects.
Change the gradient as you want on one instance;
Open the Graphic Styles palette (Window > Graphic Styles or Shift+F5;
Drag your correctly gradiented object into the palette to create a new Graphic Style;
Select all other objects;
Click the Graphic Style in the palette.
For the future only: Drag an object to the Symbols panel. From there you can drag multiple instances of it to the artboard. Edit the original in the Symbols panel or one of the instances on the artboard. All instances will get the same edit including the gradient.
Auto tracing a raster image is not a good way to do this. The result of auto tracing a complex image with gradients is usually rubbish. In my opinion, it would be better to recreate it manually, i.e. re-draw it from scratch. This is not a simple task.
This is not a tutorial, but here's a breakdown of some basic steps that could be taken to reproduce such a ...
Adobe doesn't give excuses. It's not implemented and that's that. A marketing person could say "Our software is designed for highest quality, best performance and to meet customer's needs with pinpoint accuracy. Wish you well and happy new year!".
You can insert a layer mask to make the transparency as an extra step. Make a gradient map where the stops are ...
I like to use the 'minus front' option on the pathfinder for this kind of thing. Make sure your 'K' is on the layer above the circle. If the gradient messes up like this you can throw your net over the remaining shapes from the circle and hit command + 8 or go to object in your top bar and follow this path object>compound path>make.
This should get you ...
If you have a 'live' gradient applied to an object within Illustrator, you can generate a set of flat swatches by selecting the object and clicking the 'edit gradient' (in the gradients palette). Add some nodes to the gradient wherever you want a new colour. Then, go to your swatches palette and create a new colour group, using the 'from selected artwork' ...
The best solution is to create a single path, either via copying and editing, or from scratch, which matches only the outline of the bus shape. Then use this new, simpler shape, to define the clipping mask.
I can suggest a method to make the cone, but I think the gradients will probably have to be created manually. I can't really think of a quick way of doing them. Sorry about that.
Anyway, here goes:
Select the circle and squish it into an oval
Copy it, paste in front, and group the copy
Hide the group
Use the Lasso Tool to select the middle anchors
This is for Illustrator
Draw a white filled square
Use the Mesh tool (U) to select a corner
Double click on the fill colour icon, choose a colour from the colour picker
Repeat steps 2 and 3 for each corner