• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1999.10a
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• pp.363-369
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• 1999

In these days, there are a lot of studies in the port automation, for example, unmanned container trasporter, unmanned gantry crain, and automatic terminal operation systems and so on. In terms of loading and unloading equipments. we can consider container transporter. This paper describes the automatic control for the UCT(unmanned container transporter), especially steering control systems. UCT is now operated on ECT port in Netherland and tested on PSA ports in Singapore. So we present a design on the controller using neural network PID(NNPID) controller to control the steering system and we use the neural network self-tuner to tune the PID parameters. The computer simulations show that our proposed controller has better performances than those of the other.

• Korean Journal of Agricultural Science
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• v.37 no.2
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• pp.295-302
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• 2010

Electro-hydraulic transmission (HST) and an electronic control system was designed, and performance of the components were investigated through indoor tests. When input values for HST swash plate control were given at 3 levels (5, 10, 13 degrees) in forward and reverse directions, the errors were less than 0.6 degrees. Response time was in ranges of 0.14 ~ 0.16 s and 0.16 ~ 0.2 s for forward and reverse direction controls while driving, and the values were 0.23 ~ 0.25 s and 0.18 ~ 0.23 s at static condition, respectively. Similar experiments for left and right steering resulted errors less than 0.5 degrees. Resonse time was in ranges of 0.16 ~ 0.22 s and 0.11 ~ 0.23 s for left and right turns while driving, and the values were 0.07 ~ 0.21 s and 0.09 ~ 0.14 s at static condition, respectively. From frequency response experiments, control system appeared to follow sine waves appropriately at frequencies less than 0.8 Hz with gain of 0.11 dB and 0.09 dB for forward and reverse direction controls, respectively, and the gain decreased above the frequency. Phase difference showed a gradual increase and were less than 45 degree up to 0.8 Hz. Similar experiments for left and right streering showed that the control system appeared to follow sine waves appropriately at frequencies less than 0.8 Hz with gain of 0.28 dB and 0.26 dB for left and right steering controls, respectively, and the gain decreased above the frequency. Phase difference showed a gradual increase and were less than 45 degree up to 0.8 Hz, which was the same as for the forward and reverse controls.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2365-2368
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• 2001

This paper describes a fuzzy steering controller for an autonomous mobile robot with MR sensor. Using the magnetic field($B_{x}$, $B_{y}$, $B_{z}$) obtained from the MR sensor, we designed fuzzy controller for driving on the road center. Fuzzy rule base was built to magnetic field($B_{x}$, $B_{y}$, $B_{z}$). To develop an autonomous mobile robot simulation program, we have done modeling MR sensor, dynamic model of mobile robot and coordinate transformation. A computer simulation of the robot (including mobile robot dynamics and steering) was used to verify the steering performance of the mobile robot controller using the fuzzy logic. Good results were obtained by computer simulation. So, we confirmed the robustness of the proposed fuzzy controller by computer simulation. Also, we know that proposed control algorithm was applied to real autonomous mobile robot.