Artist needing robotics advice for a project

Hello!

I have an idea for a sculpture that would involve some kind of automated mechanism. It's hard to describe it in words, but essentially I want to make a realistic heart out of paper mache and chicken wire, leaving the inside hollow. Inside of the "exoskeleton" I want to put some kind of pump mechanism filled with fake blood that can squirt the blood out in a heartbeat pattern.

I have pretty much no experience doing this kind of thing (im not even sure if this is considered robotics) so I wanted to see if anyone has suggestions on how I can do this in the simplest most beginner friendly way.