The technology competitions of automobile manufacturers are getting hot. The characteristics of the environment friendly automobile are not only lowering the emission of harmful exhaust gas through the change of the power source, but also paying great attention to improvement of the power efficiency. As the market for pure electric vehicles continues to grow, we have analyzed the global technology competitiveness by DCT (Dual Clutch Transmission) patents. Clustering can be classified into five types ; 1) a cluster associated with a dual clutch transmission system, 2) a cluster of a torque transmission device and a reverse speed ratio, 3) a cluster of co-planar sets and dual clutch assemblies related to transmitting devices, 4) Device clusters, and 5) a cluster of synchronizers and clusters to prevent simultaneous operation of dual clutch transmissions. In recent years, demand for pure electric vehicles has been rapidly increasing, and patent applications related to DCT have been steadily increasing for energy efficiency of motor power sources.

A precise control of the launcher in MLRS(Multiple Launcher Rocket System) is important for a mission completion. During the field operation of the MLRS, a friction noise was heard in the elevation clutch that controls the launcher. It was confirmed that unsteady friction between friction plates and clutch plates has caused the noise in the clutch. Conducting the analysis of drive mechnism in the clutch, there was a possibility of the unsteady friction because of moderated spring constant. Therefore, after performing experiments on the elevation clutch varied with spring constant, it was determined the proper spring constant. Finally, an improvement on the spring constant in the elevation clutch is expected in the future by utilizing the result of this study.

This paper is a case study of reliability assessment with field warranty data of Clutch Master Cylinder (CMC) in hydraulic clutch system. We estimate lifetime distribution using field warranty data which contain much useful information for understanding reliability of the system in the real-world environments. However, the estimated parameters are far from existing reference values, which seems to be caused right censored field warranty data. To modify the parameters, we use the information of the durability test which is performed to verify that the lifetime of the item meets the required level. After that, we can observe that the modified parameters are closer to the existing reference values. This case study shows a possible idea to supplement lack of right censored field warranty data and its applicability.

This paper is a case study of reliability assessment with field warranty data of Clutch Master Cylinder(CMC) in hydraulic clutch system. We estimate lifetime distribution using field warranty data which contain much useful information for understanding reliability of the system in the real-world environments. However, the estimated parameters are far from existing reference values, which seems to be caused right censored field warranty data. To modify the parameters, we use the information of the durability test which is performed to verify that the lifetime of the item meets the required level. After that, we can observe that the modified parameters are closer to the existing reference values. This case study shows a possible idea to supplement lack of right censored field warranty data and its applicability

A variable release torque-based compliance spring-clutch (VCSC) is presented. VCSC is a safe joint to reduce the impact of collisions between humans and robots. It is composed of four functional plates, balls, springs to make some functions in compliant movement, release mechanism, gravity compensation during its work. Also, it can estimate torque applied to a joint by using distance sensor and parameters of cam profile. The measured variable torque of prototype is 4.3~7.6 Nm and release torque is 4.3 Nm. In our future studies, a calibration for torque estimation will be conducted.