High-fidelity 3D Haptic Shape Rendering on Handheld VR Controllers
dl.acm.org
dl.acm.org
I have noticed many of the same effects using the novint falcon haptic controller. It almost feels as if your hand is being pushed on when in fact it is not.
Interesting that it does occur at all.
I've seen papers done using these kinds of haptic systems combined with co-located graphics where the graphics and haptic systems displayed different information. What they found was just how dominant the visual system is and how haptic and proprioceptive were definitely secondary.
With a deformable surface you can make the graphics deform more than the haptic surface and people will think it's softer.