Entries by Prof. McCarthy

2016 Mechanisms and Robotics Conference

The 2016 Mechanisms and Robotics conference is part of International Design Engineering Technical Conferences organized by ASME International in Charlotte, North Caroline, August 22-24. Plenary speaker Bernard Roth is the Academic Director of Stanford University’s d.school and the author of the Achievement Habit. For some reason, ASME has broken these links to the 2016 IDETC conference, but you can find […]

Motion Gen Linkage Design App

MotionGen is a planar four-bar linkage simulation and synthesis app that helps users synthesize planar four-bar linkages by assembling two of the planar RR-, RP- and PR-dyad types, (R refers to a revolute or hinged joint and P refers to a prismatic or sliding joint). The input task is a planar motion given as a set […]

Mechanical computation and algebraic curves

A mechanical computer that draws an algebraic curve is a useful device, and  Mathematicians Michael Kapovich and John Millson have shown that a design always exists. This is Yang Liu’s design of a mechanical system that draws an elliptic cubic curve. Here is how it is done. Algebraic curve. An algebraic curve is the set of points P=(x, […]

Want a patent? Try a Six-bar linkage

Patents including six-bar linkages are rare. Thousands of U.S. Patents have been awarded over the past forty years that involve four-bar linkages, but less than a hundred involve six-bar linkages, Figure 1. Add two bars to a four-bar to get a six-bar. A four-bar linkage, familiar to all mechanical designers, has an input lever connected […]

Fourier Curve Tracing

This animation by Yang Liu is inspired by the mechanical Fourier synthesizer described by Dayton Miller, see A 32-element harmonic synthesizer. This mechanical system combines the terms of a Fourier approximation of the batman curve found on Wolfram.com. The video below shows this device draws the batman curve.

Heart Trajectory

This mechanical system was designed by Yang Liu to trace the shape of a heart. The work is inspired by the mechanical 32-element harmonic synthesizer described by Dayton Miller in the 1916 article in the Journal of the Franklin Institute.