I would like to know whether the technology exists to create
pressure-sensitive fabrics.  A fabric, specifically a heavy fabric
such as canvas, that changes colour when it is struck or pressure is
applied and then slowly reverts back to its original colour.

I haven't but I have heard of materials that change color when heat is
applied like your hand. Pressure sensitive would have to involve
piezoelectric materials electrically attached to Thermotropic Liquid
Crystals. Curious: what are you trying to accomplish with this
knowledge if I may ask?

://www.google.com/search?lr=&ie=UTF-8&oe=UTF-8&q=Thermochromic%20Plastisol%20Ink
://www.google.com/search?lr=&ie=UTF-8&oe=UTF-8&q=Thermochromic

if you need information please be more specific.

TheGuyThatKnows

I am not looking for a thermal-sensitive fabric.  That would not be
suitable for the application that I have in mind.  The fabric needs to
change in some way upon impact so as to show where the impact occured,
and then revert back to its normal appearance relatively quickly (in
less than 30 seconds).

I cannot specify the application that I have in mind but think of
beating a rug and seeing some mark to show where your blows hit the
rug and then having the marking slowly disappear.

Any assistance would be greatly appreciated.