Folding Cartons with Fixtures: A Motion Planning Approach

Packaging products such as telephones and two-way radios after assembly is a common manufacturing task. Carton folding is a packaging operation performed by human operators or with fixed automation. We present a flexible method to fold cardboard cartons using fixtures; a carton blank is folded by moving it through a fixture with a robot. This method of using interchangeable fixtures enables rapid changeovers between product models. We outline a procedure to design a fixture given a carton and a folding sequence. We present an implemented motion planning algorithm that generates all folding sequences for a carton by modeling it as a many degree of freedom robot manipulator with revolute joints and branching links. A fixture constrains the carton to move along paths consisting of line segments in its configuration space, and the motion planner generates these paths. To illustrate the method, we selected a folding sequence for an example carton, designed a fixture, and demonstrated folding of the carton from blanks with an industrial robot.