Search Results

This study proposes a motor-controlled torque-vectoring differential equipped with electric hybrid functionality, hereinafter referred to as H-TD (Hybrid Torque-vectoring Differential). The mechanism of H-TD consists of an open differential, a planetary gearset, an electric motor, a clutch brake, and a clutch. The main difference between H-TD and preciously published TVD (Torque Vectoring Differential) systems is that it uses the electric motor to be able to not only distribute torque between output shafts, but also provide additional hybrid power. Hence, H-TD provides the possibility to integrate multiple functions into a single system. Furthermore, H-TD can be utilized in both hybrid electric vehicles and electric ones. Firstly, the constitution of H-TD mechanism is introduced, and three operation modes of the system, control strategy, as well as the dynamic models for the system are presented.

A hybrid transmission may be in any combination of a power-split, series or parallel configuration. This study is aimed to develop a hybrid transmission with six possible configurations: power-split, series, two parallel configurations, and two EV configurations. The Function Power Graph (FPG) methodology was applied in this study. After creating and merging FPGs, a possible solution consisting of only one planetary gearset, one ICE, one MG1, one MG2, two rotating clutches, and one brake clutch was synthesized to satisfy all configuration requirements. This transmission was based on power-split configuration which can switch to other configurations. The parallel configuration I extracted more power from MG1 and ICE during lower speed driving in order to utilize the two sufficiently, and respond to the increased desire for horsepower in the market. Additionally, parallel configuration II was set up so that ICE can directly propel the vehicle during freeway cruising.

A systematic modeling methodology using Function Power Graph (FPG) to analyze mechanical systems is proposed in this paper, and the novel Centrifugal Anti-lock Braking System (C-ABS) is used as the example. In this paper, a systematic modeling process combined with the FPG method and SimulationX-based modeling has been demonstrated. First, schematic diagram and working principle of the C-ABS model has been developed and illustrated. Based on the FPG method, several symbols (power unit, clutch/brake unit, and connection unit) for the C-ABS have been introduced. Second, system mode, operation, and function inspection of the C-ABS have been analyzed. Then, each component model of the C-ABS (wheel, disc brake, gearbox, and centrifugal braking device) has been established, and then the schematic diagram of the C-ABS has been transferred into practical image of the system structure (or physical model) through SimulationX to identify the dynamic characteristics of the C-ABS.

The purpose of the present study is to carry out failure analysis of a scooter's continuously variable transmission (CVT) system that is considered to be one of the key components of the scooter. In the study, many reliability analytical tools such as failure mode, effect and criticality analysis (FMECA) and fault tree analysis (FTA) are used to identify possible failure modes of the CVT system and its subsystems. The failure effects of components on the CVT system are emphasized in particular. Aside from the qualitative evaluation, simulation algorithms are also developed to examine the performance of the CVT system and assess the reliability of the belt. Through the study, it is found that mechanical wear at both sides of the V-belt is the most serious problem that affects the CVT performance. The sliding collar of the driven pulley is another component that has to be observed carefully. Some design improvements are pointed out at the end of the paper.