I'm trying to create a dashed line with arrow heads along its length in Illustrator. I don't think it's possible to do just with dashed line options (is it?), so I'm trying to create a brush which would have the same effect. The problem is the arrow heads are distorting on corners which does not look good. Is there a way to work around this?
Another method would be to use a Scatter brush instead of a Pattern brush.
Create your arrow head, select it and create new Scatter brush. Select "Rotation relative to path".
Select your path, apply Scatter brush to your stroke, then go to Appearance panel and add a new dashed stroke.
The good thing about Scatter brush is that they don't distort.
The bad thing is that it will not adapt to the dash, meaning you'll end up with parts where arrow will overset dash, which will be quite inelegant.
Another issue will be that Scatter brush will start at the start of your path (logical isn't?) but we want it to end at the end really... Setting rotation to 180° will solve but that means you must start drawing your path from the end...
So it definitely isn't a perfect method, but it's worth mentioning it..
If using a pattern brush, then one method is to modify your path curves so that the arrowheads are not positioned near to extreme curves, thus minimizing any distortion. Obviously this will take some degree of messing around with the curves.
Another more manual option is to place arrowheads individually, not as part of a brush. Here I created a brush with a gap to leave enough room to place individual rotated arrowheads.