Journal of Electrical Engineering and Technology

The Korean Institute of Electrical Engineers (대한전기학회)
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Optimal Controller Design of One Link Inverted Pendulum Using Dynamic Programming and Discrete Cosine Transform

  • Kim, Namryul (Dept. of Electrical Engineering, Myongji University) ;
  • Lee, Bumjoo (Dept. of Electrical Engineering, Myongji University)
  • Received : 2017.10.23
  • Accepted : 2018.04.24
  • Published : 2018.09.01
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Abstract

Global state space's optimal policy is used for offline controller in the form of table by using Dynamic Programming. If an optimal policy table has a large amount of control data, it is difficult to use the system in a low capacity system. To resolve these problem, controller using the compressed optimal policy table is proposed in this paper. A DCT is used for compression method and the cosine function is used as a basis. The size of cosine function decreased as the frequency increased. In other words, an essential information which is used for restoration is concentrated in the low frequency band and a value of small size that belong to a high frequency band could be discarded by quantization because high frequency's information doesn't have a big effect on restoration. Therefore, memory could be largely reduced by removing the information. The compressed output is stored in memory of embedded system in offline and optimal control input which correspond to state of plant is computed by interpolation with Inverse DCT in online. To verify the performance of the proposed controller, computer simulation was accomplished with a one link inverted pendulum.

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References

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