is this possible to do? please help

Hipster_Owl_Studios

ok so I'm making my actor pace back and forward through the method t-shirt booth showed on his website. and i want my actors to continue pacing back and forward on the same direction even when hit by another actor. when my ball actor hits the actors pacing back and forward my actors change course and eventually fly of the screen can someone help how to solve this problem? i tried messing around with constrain attribute but i could get it to go. any help would b great! thanks