We want to create a bag that can comfort you as a pet can do. The interaction is simple. You need to stroke the bag. The bag will then start breathing, it's heart will start beating, it will give off warmth and make soothing sounds. The thing is, you can not feel the heart, breath and heat unless you hold the bag close to your body.
Perhaps, when you hit your bag it give more aggressive sound.
Plan for day two:
-Buy sleeping donkey toy, to hack out the breathing action.
-Use 2/3 vibro's for purring effect.
-Program the purring sound with the piezo
-Prepare a basic bag onto which the electronics can be placed.
-Use conductive capacitor sensors to register the stroking of the bag.