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South pointing chariots have been the fascinating mechanical devices for designers for a long time. Up to date, the gear trains used in the south pointing chariots are the planetary gear trains with two degrees of freedom and with train value -1. The purpose of this work is to present a systematic approach for the kinematic design of south pointing chariots with planetary gear trains. According to train circuit equation, we propose equation of motion of PGTs. Then, based on the equation of motion of PGTs, we derive two constrained equations for the kinematic design of south pointing chariots. Finally, based on these two equations, we synthesize the corresponding south point chariots for arbitrary planetary gear trains with two degrees of freedom. Some design examples are illustrated to demonstrate the design process.

The traditional planetary grinding device can only polish one optical fiber ferrule. The other grinding device with donut polishing trace is also proposed for polishing wafer. This grinding device has a problem, that is, “the polishing qualities of different points on the wafer are not the same”. Hence, this paper proposes a new planetary grinding device for polishing more optical fiber ferrules and more wafers. Based on the kinematics of planetary gear train, the equations of polishing trace and velocity are derived. Then, the velocity deviation percentage (Vdp) is calculated, which is an important design parameter. Area ratio (AR) is defined as polishing area divided by grinding pad area. The area ratio (AR) is another important design parameter for designing planetary grinding devices. In this paper, two design examples are used to illustrate the design process. The research results of this paper can provide an experience for the systematic design of planetary grinding devices.

Typically, the motion of the output link of the mode clamping mechanism has reciprocating linear motion, but the motion of the input link can be reciprocating rocking motion or reciprocating linear motion. In addition, the mold clamping mechanism must have a dead-position configuration for the mold at the closed position. This article focuses on the kinematic design of a mold clamping mechanism having an input link with reciprocating linear motion and having dead-position configuration at closed positions. First, four design concepts of mold clamping mechanisms are proposed based on the mechanism creative design methodology. Then, one of the design concepts is chosen as the design example to illustrate the kinematic design of the mode clamping mechanism with minimal maximum acceleration. According to the design requirements, the best design of the mode clamping mechanism of this article is better than the existing patent by reducing 43.5% acceleration and 18.6% driving force.

An automotive gear differential is a joint-fractionated planetary gear train with two degrees-of-freedom. We summarize the characteristics of planetary gear trains and the design constraints of noncoupled automotive gear differentials to synthesize their corresponding kinematic graphs. Based on these graphs and the proposed respecializing process, we generate the atlas of design concepts for automotive gear differentials with any types of gear pairs. As a result, there are 4, 25, and 156 design concepts for five-, six-, and seven-bar automotive gear differentials, respectively.