Four-Bar 0 0 Double Rocker 04
(Interactive Simulation)

go to editable simulator
If simulation does not appear Download J2SE v 1.3.1_09

Instructions: Click and drag any ungrounded node of the mechanism to make it move. Nodes on triangles are grounded and cannot move. Select a node and you can toggle its grounding or tracing states. Select a link and you can make it longer or shorter using the buttons.