Automated Guided Vehicle (AGV) is commonly used in manufacturing plant, warehouse, distribution center, and terminal. AGV is self-driven vehicle used to transport material between workstations in the shop floor without the help of an operator, and AGV includes a material transfer system located on the top and driving system at the bottom to move the vehicle as desired. For navigation, AGV mostly uses lane paths, signal paths or signal beacons. Various predominant sensors are also used in the AGV. However, in the conventional AGV, there is a problem of not turning or damaging nearby objects or AGV in a narrow space. In this paper, a new driving system is proposed to move the vehicle in a narrow space. In the proposed driving system, two sets of the combined steering-drive unit are adopted to solve the above problem. A prototype of AGV with the new driving system is developed for the comparative analysis with the conventional AGV. In addition, the experimental result shows the improved performance of the new driving system in the maximum speed, braking distance and positioning precision tests.

The purpose of this study is to design and control position and torque based on the steering controller of power tiller simulator developed by the National Institute of Agricultural Sciences. The tiller simulator selects sensors and motors to detect the motion of the mechanism required for steering, and controls the tiller's steering controller through the PID control method and the PWM control method which can control simultaneously the position and torque. Simulation tests are carried out under various conditions to verify the efficiency of the proposed controller. The power tiller training simulator can be used as a means to prevent agricultural machinery accidents caused by human factors. Through the simulator, the driver can experience a variety of tasks without any risk of collision, the results of his actions, and learn the cause and effect concepts, which can be used for safety education and accident experience.

This paper has been carried out the forming analysis, die stress analysis, and relevant tests for the straightness improvement of hollow shafts with blocktooth. Hollow forward extrusion is a process that a material in a die is pressed with a punch and the material is formed into the same direction through the gap of a mandrel and a bottom die. For an asymmetric shaped product, due to the difference of reduction ratios of the cross sections in its extruding, a phenomenon that the product bends from the difference of the flow speed comes to occur. As applying the key to the mandrel has a uniform flow speed, bending problem was solved. These were processed using Deform-3D as a finite-element analysis program. Analysis was compared with the experiment. Keyway height of the mandrel has been confirmed that the straightness best when it comes 0.1mm. These study are expected to be available as fundamental data in die design necessary for the manufacture of asymmetric goods in the future.

This paper carried out design in order to reduce the process of asymmetric pinch yoke, one of the important parts which transfer power to wheels through gearing box in automobile steering system. The purpose of the study is to reduce prime costs and strengthen competitiveness by designing the total 8 processes including the up-setting and forging process of the No. 1 as the forging process the current method of production. The process with die stress analysis by using the finite element method have been carried out through new optimal die design. As this study result, it is expected that die life can be secured as excellent material flow and caused by forming load. A prototype has been produced by basis of the analysis result and the reduction of the process was successful. As the unit price is lower than that of the current process, the competitiveness can be expected.

When manufacturing die casting mold, generally, the casting layout design should be considered based on the relation between injection system, casting condition, gate system, and cooling system. Also, the extent or the location of product defects were dif