There are 2 problems to solve:
- To distribute the barbs evenly along the length of the curve
- To do so without distorting the barbs
This used to be a typical use for Dupliframes, but they has been removed from 2.8.. they apparently don't play well with the new dependency graph.
so you can treat the barbs as particles (which will not be distorted), and distribute their emitter evenly along the curve. Distortion of the emitter will not be inherited.
- Create a plane to be an emitter for the barbs
- Give the emitter-plane Array and Curve modifiers, both along its Z, to distribute instances of it along the curve
- Give the plane a particle system with the barb as target object.. particle settings something like the illustration below:
(Lifetime: as long as you like .. Count: the count of the plane's array modifier, the Barb object edited to have its local X along the curve)
Result: (plane yellow, barb blue, curve red)..
.. which has the advantage that you can put a random twist on to the barbs, if you want to, using the 'Phase' settings in the particle system's 'Rotation' panel.