Figure 1: A photograph showing the robotic arm along with the circle it is programmed to characterize. The robotic arm is constructed using the LEGO NXT Mindstorms System. It employs one motor to allow it to rotate about a vertical axis indicated by the black line in the top center of the image and two motors to extend and lower the arm about the joints located at the positions indicated by the short arrows. The LEGO light sensor, also shown in the inset, is attached to the end of the arm as indicated by the long arrow.