Driving mechanism, the central part of a robot, was designed in this study. Power for the motive drive was acquired by directly connecting the motor shaft in worm shape of the low-end DC motor, car window motor, to a decelerator. The decelerator consists of a worm gear to receive power from the motor shaft, a pinion gear to be connected in line with the worm gear, and an output shaft to be engaged to the pinion gear. Motion driving is achieved by the power from the motor shaft with the designed gears, transferred to the deceleration mechanism and to the output gear

On cold start operation of an SI engine, a catalyst shows poor performance before it reaches activation temperature. Therefore, fast warmup of the catalyst is very crucial to reduce harmful emissions. In this study, an appropriate control strategy is investigated to increase exhaust gas temperature through changes of spark timing. Combustion stability is also considered at the same time. Exhaust gas temperature and pressure of combustion chamber are measured to investigate the effects of spark timings on cold start and idle performance. Experiments showed that retarded spark timing promotes the combustion at the end of expansion stroke and increases exhaust gas temperature during cold start.

Dry CVT(Continuously variable transmission) consists of a driving pulley and a driven pulley joined by rubber V-belt. Each pulley consists of a fixed flange and a movable flange. The movable flange of the driving pulley has the centrifugal roller and a ramp plate in the flange. The movable flange moves toward a fixed flange under the actuation of a centrifugal roller, as the driving pulley speed increases. The main advantages of the Dry CVT with V-belt, which has been popular in Asia, are a simple mechanism, less maintenance and low cost. The important claim which have an influence on the performance of the Dry CVT is the wear of the centrifugal roller. In this study ball type is proposed instead of roller type of movable flange to resolve claim. Also experiments are carried out for new model to evaluate performances.

World Widely, a lot of gearboxes are being developed for the increase of fuel efficiency. Among them, CVT has an infinite gear and shifts gear at the best situation which makes it have no impact by changing speed and reduce the expense of fuel. We designed and manufactured 2ranked gearbox for V-belt similar to CVT. We studied an energy generated when it is functioning and had an experiment of forwarding power of it. These studies are planned to find out its functions and the efficiency of forwarding power of it.

On cold start operation of an SI engine, a catalyst shows poor performance before it reaches activation temperature. Therefore, fast warmup of the catalyst is very crucial to reduce harmful emissions. In this study, an appropriate control strategy is investigated to increase exhaust gas temperature through changes of spark timing and exhaust valve timing. Combustion stability is also considered at the same time. Experiments showed that retarded spark timing promotes the combustion at the end of expansion stroke and increases exhaust gas temperature during cold start.An advance of exhaust valve timing decreases residual gas in cylinders due to decrease of valve overlap period. It helps improvement combustion stability by virtue of reduced residual gas. A control strategy of proper valve timing and spark timing is suggested in order to achieve fast light-off of the catalyst and stable operation of the engine in a cold start and idle operation

On cold start operation of a gasoline engine, a catalyst shows poor performance before it reaches activation temperature. Therefore, fast warmup of the catalyst is very crucial to reduce harmful emissions. In this study, an appropriate control strategy is investigated to increase exhaust gas temperature through changes of exhaust valve timing. An advance of exhaust valve timing decreases residual gas in cylinders due to decrease of valve overlap period. A control strategy of proper valve timing is suggested in order to achieve fast light-off of the catalyst and stable operation of the engine in a cold start and idle operation.

The scooter CVT is consisted of driving pulley, rubber V-belt and driven pulley. A driving pulley of CVT plays a vital role. In this study, contact forces of movable flange, roller and ramp plate are analyzed for wear of roller. As the results, 1) when incline angle of ramp plate become decreased, reaction difference of ramp plate and movable flange become increased, so roller wear can be decreased, 2) when radius of movable flange profile is increased, reaction difference become increased also. Roller wear had been caused serious claim. Based on the analysis, advanced model of driving pulley is presented.