Kinematic Analysis of Robotic Bevel-Gear Trains - Nov/Dec 1986 Gear Technology

Introduction In robot configurations it is desirable to be able to obtain an arbitrary orientation of the output element or end-effector. This impliesa minimum of two independent rotations about two (generally perpendicular) intersecting axes. If, in addit:ion, the output element performs a mechanical task such as in manufacturing or assembly (e.g., drilling, turning, boring, etc.) it may be necessary for the end-effector to rotate about its axis. If such a motion is to be realized with gearing, this necessitates a three-degree-of-freedom, threedimensional gear train, which provides a mechanical drive of gyroscopic complexity; i.e., a drive with independently controlled inputs about three axes corresponding to azimuth, nutation, and spin. In a recent artide(2) an ingenious bevel-gear train of this type was described, and the-article refers to a project headed by Mr. Louis Erwin, Project Coordinator of the Bendix Cor-