Link xPendulumArmGimbalLink = new Link("xPendulumArmGimbalLink");
xPendulumArmGimbalLink.setMassAndRadiiOfGyration(0.05, 0.02, 0.02, 0.02);
xPendulumArmGimbalLink.setComOffset(-ARM_LENGTH/2.0, 0.0, 0.0);
Graphics3DObject xPendulumArmGimbalLinkGraphics = new Graphics3DObject();
xPendulumArmGimbalLinkGraphics.addSphere(0.04, YoAppearance.Red());
xPendulumArmGimbalLinkGraphics.rotate(-Math.PI/2.0, Axis.Y);
xPendulumArmGimbalLinkGraphics.addCylinder(ARM_LENGTH, ARM_RADIUS, YoAppearance.Pink());
// Pen:
xPendulumArmGimbalLinkGraphics.identity();
xPendulumArmGimbalLinkGraphics.translate(-ARM_LENGTH, 0.0, -PEN_HEIGHT);