particle hair comes through mesh even with collision

[Ksusha (Ksusha K)]

Hello
I am using blender 3.2.1
I have a small animation of a suzanne’s head and a hair strand paranted to it.

The hair is particle hair. It was made this way: 1) making a curve circle and a path curve, in object data properties Geometry → object and selecting the curve circle. 2) converting result of previous step into a mesh 3) deleting some vertices 4) Fibermesh in HairNet. (this tutorial “Hair addon blender (HairNet) Part 2” https://youtu.be/ebM4JZKTITY)

My problem is: when suzanne’s head moves slowly (± 15 frames between each keyframe) hair works fine (hair does not come though head), but when the head moves faster (± 7 frames between each keyframe) hair starts to come throgh suzanne’s ear.
screenshots

Could you please tell me how to makr hair collide with suzanne?

I want the hair strand not to come through Suzanne’s ear while Suzanne’s head is moving fast.

I have ticked “hair dynamics” box. There tried setting a Collision Cillection in hair dynamics, but it did not change anything.

I have set a collision modifier to suzanne’s head in physics properties. In “soft body and cloth” section i played with Damping, Thickness Outer, Inner, but to no avail.

I am new to blender and I will be greatful for any help

Link to my file https://cloud.mail.ru/public/zQk3/AiZjPUZAQ

[thetony20]

First couple of things to look at are the resolution of the hair strands and the monkey head.

Basically if there isn’t any near vertex in the hair to collide with the mesh, then the hair cuts through. You’d also need to increase the collision steps, especially the faster the movement, but that will take longer to calculate.

Also, keep in mind, if you are using Child hairs at all, those are not tested for collisions, so if the main hair gets close, the child hair will cut through.