How to create a specific shape/Blend circles of different sizes

Thank you for your kind words, Piter.

For my part, I trust Illy (job description Adobe Illustrator) unconditionally.

When you Expand/Expand Appearance/Flatten Transparency/do other things to simplify the structure of objects, there is a possible/likely/inevitable loss, which may be in quality/flexibility/usability/reversibility/accuracy, so there is no reason to worry about a small change in numbers.

Always set a copy of the original artwork aside before your starting to destroy it.

To encounter inaccuracies, there is no need to look further than a default circle, one of the objects most used.

You can try to Click with the Ellipse Tool and set W=H to 1,000 or 10,000 pt, then Object>Transform>Rotate by 7.5 degrees and follow up by  Ctrl/Cmd+D to repeat at least 5 times to reach 45 degrees rotation (or go all the way round), and enjoy or shudder as you look at the W and H values.

Edit: I have just extended the Graphic Style post to also include instructions for other numbers of circles.

Piter, I am sorry.

When I tried out your set I got the same strangeness; and then I realized that parts of the instructions in 4b) and 4c) were missing, lost between doing and describing.

I have added the missing parts in red in that post, and that changes the calculations as follows, changes shown in red:

49.895 (length)
- 16.6 (big circle)
- 28.8 (small circle 9.6 x 3)
/ 4 for each space
=
1.12375 + 9.6 = 10.72375

Then I added 8.3 to that 1.12375 (half the W/H of the larger circles) to the first gap and this was the result:

Then add 3.5 to that 10.72375 (half the difference between the W/H of the larger circles and the W/H of the smaller circles, which is 16.6 - 9.6 = 7), thereby getting a first gap that is 14.22375.

This ought to get it right, finally.

Piter,

In the blend way, were you actually using a circle with 5 Anchor Points created with the Circle script to start with and then resized?

The images look as if you have Anchor Points at the sides corresponding your using/starting with a default circle 4 in total. Especially large/complicated Blends can be confused by less optimized paths are used as spines.

In the Graphic Style way you can also start with a 5 Anchor Point circle created with the Circle script. Can you show what you have made so far?

Piter,

Here is a Blend approach; it is easier to explain than I believed, and more straighforward than it sounds.

And, like the Graphic Style approach it is fully accurate in itself, no need for any adjustments (which may be less than fully accurate).

As I still (mis)understand it, you wish to have 5 larger circles and 15 smaller circles placed evenly round a stroked circle of a certain size, evenly in the sense that you have the same space in between circles, corresponding to Align>Distribute Spacing rather than Align>Distribute Objects (the latter having the same distance between centres or similar).

You can, see imagery below:

1) To create the overall circle, use the free Circle script from the link (佐藤浩之, Satō Hiroyuki) below, setting the number of Anchor Points to 5, then change the W = H to the desired value and the Stroke Weight to the desired value with Round Cap and Round Join to form the background part of the final shape; rotate it by 90 degrees to the one Anchor Point at the top;
2) Ctrl/Cmd+C+F to create a copy on top, lock the original, and select the copy circle, then cut at the top Anchor Point;

Now the overall circle is ready for the Blend;

3) Create the first of the larger circles at the desired W = H and fill/nostroke;

4) Ctrl/Cmd+C+F to create a copy on top, then change the W = H to that of the smaller circles, then select both and Click the larger circle once more, then Align>Distribute Spacing horizontally with the value 0, to have them beside each other (you can move the smaller circle in other ways, but you need the Distribute Spacing later so you may as well have an easy start);

5) Select the smaller circle and Object>Move a copy horizontally by its W = H value, then Ctrl/Cmd+D to repeat;

Now you have the first set of circles;

6) Select the circle set and Object>Move a copy horizontally by the sum of the W = H values (1x large and 3x small), then then Ctrl/Cmd+D four times to repeat;

Now you have 6 sets of circles;

7) Select the last 3 circles and delete them;

Now you have 5 sets of circles with an additional larger circle at the end;

8 ) Select the overall circle from 2 and pick the Length value in Document Info, then subtract 5x the W=H value of the larger circles and 15x the W=H value of the smaller circles, then divide by 20;

9) Select all the larger and smaller circles, then Click the leftmost one, then insert the value from 8 instead of 0 and Align>Distribute Spacing;

Now you have the right distances between the circles;

10) Object>Blend>Blend Options, set Spacing to Specific Steps = 1 and Orientation to Align to Path;

11) Object>Blend>Make;

12) Shift>Click the overall circle from 2) and Object>Blend>Replace Spine;

Now you have an orderly mess round the overall circle where every second circle is unwanted;

13) Object>Blend>Expand, then deselect, then ShiftClick with the Direct Selection Tool on all the unwanted circles, every second starting and ending beside one of the larger circles, then press Delete;

14) Unlock the original circle from 1), then select everything and Ctrl/Cmd+G to Group.

Now everything ought to look right;

15) If you wish, you can deselect and Direct Select the topmost larger circle which is a double, then delete it.

Link to the Circle script and others by (佐藤浩之, Satō Hiroyuki):

http://shspage.com/aijs/en/

Click/RightClick to see full size, or Click Here to see it in Chrome 

Click within the image to Zoom in.

Another way

Using "Type on a Path Tool"

Make a partially doubled circle.

Create text to put on this path.

Adjust the position and spacing.

well, in eal work I would go follow:
1. Draw the main circle and the top bigger element. 

2. Create 4 copies using 18° rotation

3. Change the size of internal circles using Object > Transform > Transform Each

4. Rotate a bit the first and the third small circles to adjust the space. With my big/small proportions it was 3,3° and -3,3° respectively, yours may require some search but the needed angle is certainly between 3° and 4°.

5. Delete the lower big circle, select all the left circles and copy them rotating on 72°

6. If you need the solid shape, then 2 more steps:

- Outline stroke of the main circle

- Unite all the elements:

Looks long but really it took less than 5 minutes.

Do you need to find a method to create similar ones or is it just about exactly this one?

If the latter: calculate the exact angles and then first do the big ones, then copy/rotate one of the small groups and then copy/rotate the group.

well, the easiest way is to create blend with the same size, then expand it (Object > Blend > Expand), select all the circles you need to grow and use Object > Transform > Transform Each (make sure to set the anchor point in center)