Peek-A-Bear Analysis - William Hancock

The Peek-A-Bear is a Karakuri Paper model, that will play peek-a-boo with the user. It works using a cam shaft as the input of a four-bar linkage and two five-bar linkages that come off of the four bar linkage, one to move the head and one to move each arm. As the cam shaft is spun, the head moves up and down and the arms rotate in and out to cover the face, giving the motion of peek-a-boo to the bear. Each of the linkages are a 1-DOF system coming off the same input link, meaning that the entire system is a 1-DOF system.