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This work is basically a dirigibility study applied to tricycles of human traction, HPT - Human Powered Tricycle. The behavior of the vehicle is simulated in a track with compacted floor, contend curves, straight line, up and down grades. A simplified mathematical model is used to model the system (vehicle + cyclist). As the system of equations obtained is extremely coupled and non-linear, it is necessary to use numeric procedures to solve the equations and to obtain the behavior of the system during its path in the racetrack. The influences of the track and the mass center position of the vehicle in its stability, the behavior of the vehicle using chainset transmissions and CVTs (Continuously Variable Transmission) are also analyzed.

This study aims to evaluate the impact that changes in the parameters of the project to a continuously variable transmission has on its ability to transmit torque and power. A half-toroidal transmission is cinematically analyzed and key geometric parameters and their relationships are studied and characterized. A change in the parameters of the transmission geometry allows a verification of their influence on the entire system live-time for any type of cycle, as defined in the theory of life provided the causes of failure, fatigue and subsurface. Additionally is possible to evaluate the capability of transmitting torque through the theory of Elasto-Hydrodynamic (EHD) contact relationship and the range of possible transmission ratio to be achieved. In this paper, a geometric model of a traction based Half-toroidal CVT (see figure 1) were explored by adding new geometric parameters related to the system control mechanism (the roller tilting angle).

The increasing market of the continuously changeable transmissions demands that its characteristics of performance fully are known and constantly developed. Of the some existing constructive types one initially opted to the modeling of the system of pulleys of changeable diameter and leather strap. Knowing, that the transmissions are part of the train of force of any vehicle, the model will go to include the characteristics of exit of the engine, torque and rotation and all the components of an automatic transmission that uses CVTs. The initial objective is to determine the geometry of functioning and the positioning of the leather strap in the CVT. Saber its behavior, if it is playing its role in the excellent way.

Had to the development of new projects of vehicles more economic as for example, the hybrid vehicles, have become bigger investments in transmission systems mechanics more adjusted. Thus being the increasing market of the continuously changeable transmissions it demands that its characteristics of performance fully are known and constantly developed. Of the some existing constructive types one initially opted to the modeling of the system of pulleys of changeable diameter and leather strap. To leave of this modeling one became alterations of some components and verified the behavior of this CVT in a simulation of passage of a vehicle. This passage was drawn so that the vehicle more faced daily situations of a vehicle considered in a track accented, that requested of the transmission the reactions boundary lines that supplied to torque and power of enough engine, or, so that the vehicle executed the passage, a not to leave of the limitations of the system and the CVT.