Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsBicycle Wheels Using Curves of Constant Widthhttp://demonstrations.wolfram.com/BicycleWheelsUsingCurvesOfConstantWidth/]]>http://demonstrations.wolfram.com/BicycleWheelsUsingCurvesOfConstantWidth/