With the recent development of autonomous driving technology, many researchers have studied autonomous mobile robots. Accordingly, they are developing diverse mobile robot actuators. However, most actuators mainly use reducers made of chains, belts, multi-stage gears, etc. So the volume and size of the actuators increase, and power transmission efficiency tends to be relatively low. Therefore, this study has proposed the reducer of the mobile robot actuator using a complex planetary gear train with small volume and high power transmission efficiency, and has confirmed the stability of the proposed reducer through finite element analysis.

In case of worm reducer, the worm and worm wheel are the significant design elements. Most of the worm and worm wheel are being importer and assembled because that the localization is inadequate. As the demand increases and the necessity of localization and precision grows, to develop them is now more important things. In this study, we conducted the design, manufactured prototype and performance evaluation for worm reducer for dual lead 5.2:1 servo motor. The worm reducer is analyzed design reliability by finite element method. The performance evaluation for manufactured prototype worm reducer was conducted on the backlash, operation temperature and contact efficiency with/without load and satisfied for the all test items.

During the field operation of the Korean MBT(Main Battle Tank), the multi-smoke projectile launching system failed to function. As a result of conducting analysis, it was confirm that the gear shaft of reducer was failed. Therefore, a study on improvement in impact resistance of the reducer was conducted. The reducer was improved impact resistance by changing the design and material of gear shaft. The reliability of modified reducer was investigated by finite element analysis, performance and environmental tests. As a result of analysis, a strength of the modified gear shaft was improved by about 20 times than before improvement. The results of performance and environmental test show that the modified reducer is applicable for Korean MBT under the severe conditions. The quality improvement of multi-smoke projectile launching system contributes to survivability of Korean MBT.

The mobility of the tactical vehicle is important for a mission completion and survivability. During the field operation of the MLRS(Multiple Launcher Rocket System), broken bolt was found in a final reduction gear with oil leakage. It was confirmed that the final reduction gear pad bolt was broken with ductile fracture after inspecting and scanning electronic microscope of the bolt. Furthermore, a finite element analysis on the bolt was conducted with regards to the operating conditions in the final reduction gear. Conducting the analysis, there was a possibility of the bolt being damaged when we put rusty spline and the adhesion of hub thrust pad as input parameters. Finally, improvements on the spline in the shaft are expected in the future by utilizing the result of this study.

There are many types of reduction drives for industrial uses. However, it is essential to use precision reduction drives for accuracy of position controls on robot systems. Among the precision reduction drives, the cycloid reduction drive is well known for its high performances and widely used in precision industrial field. Cycloid reduction drives are mainly used in manipulators in robot system requiring a characteristic of a high precision control. When we design this cycloid reduction drive, there are many factors that must be considered. First, a geometrical analysis of a tooth shape must be drawn from the basic concept. Secondly, load distribution, stress distribution and sliding velocity on a tooth should be calculated exactly. Finally, a computer software to optimize the design of a cycloid tooth needs developing. In this study, many different kinds of factors concerning the characteristic of a cycloid tooth were researched on the basis of the analysis of load, stress and sliding velocity on a tooth. The computer expert system to design the cycloid reduction drive was developed using a Visual C++ compiler. In conclusion, the most important factors can be obtained easily as the user put the simple input data.

The agitator with a reducer are usually using on the process of a water treatment. However, working the reducer at the field, a lubricant oil can leak out. It causes an environment pollution and a water service/sewerage pollution problem. In this study, the reducer with a drywell structure is developed in order to prevent the oil leakage. The drywell structure is that the reducer bottom housing and the support column of an output shaft are united, and taper roller bearings are in the bottom housing. During the development of the reducer, a mockup and a prototype are made by using CAD and a high speed CNC machine. Then, to prove the performance of the prototype, the performance tests, unload working test and the mechanical torque efficiency test, are conducted by the torque meter device. Also a motor velocity(rpm) control system is developed by a PID control according to the working loads(MLSS data). The results of the test are shown that the maximum torque efficiency is 88.45%, the oil leakage and the abnormal noise do not occur during the work. Therefore the reducer with the drywell structure and the motor rpm PID control system is successfully developed.