MechGen FG App Makes Design Calculations Easy

The MechGen iPad App helps you design a link that connects an input crank to the coordinated rotation of an output crank. Locate the two cranks and define their input and output angles and let MechGen FG design linkages for you. The design data and an animation of your linkage is easily distributed by email.

The use of linkages for calculation dates back to Charles Babbage’s “difference machine” from the mid 19th century. One hundred years later, Svoboda designed mechanical computers to direct artillery by fitting the input-output properties of linkages to a desired function. In 1954, Freudenstein used the newly developed digital computer to find a simple linkage that computed complex functions. This introduced computer-aided design by numerical solution of polynomial synthesis equations derived from linkage loop equations.

Today the design algorithms for six and eight bar function generators push the limits of computational ability.

MechGen FG helps the designer because it repeatedly makes routine calculations that would otherwise be very difficult, and it creates many candidate designs, which is where computational power comes into play.

An example design that the MechGen app will solve for you is that of a trashcan lid connected by a link to a foot pedal designed to open it. You want the lid to open 100 degrees so that it creates a large opening for you to put trash in it without the lid getting in the way of the entrance (because that is an annoying thing for people to deal with and this is a concern with this product) and being over 90 degrees will allow it to rest or stay open instead of falling back down and closing, but you also don’t want a person to have to move the pedal over too big a distance; you want the pedal to only move 20 degrees so it’s easy for a person to do.

This is a nice design problem. How do you get a lid to swing 100 degrees when you move a pedal 20 degrees? Well, you can start with the MechGen FG App.