2024 |
Gyunghoon Park / Hyungbo Shim / Tomomichi Hagiwara On Existence of Uniformly Marginally Stable Zeros of Linear Sampled-data Systems and its Application to Stable Inversion-based Control Journal Article In: IEEE Access, vol. 12, pp. 49826 - 49836, 2024, ISSN: 2169-3536. Abstract | Links | BibTeX | Tags: Linear Systems, marginal stability, Sampled data system @article{nokey, This paper investigates a class of sampled-data systems in which at least one of the discretetime zeros remains on the unit circle regardless of the sampling period. This type of zero is referred to as an ‘‘uniformly marginally stable’’ (UMS) zero. Utilizing this novel concept, we present necessary conditions as well as sufficient conditions for the continuous-time plant whose sampled-data model has an UMS zero. The significance of the symmetry regarding the zeros and the poles of the continuous-time plant is highlighted as it plays a vital role in enforcing a discrete-time zero of the sampled-data system to be UMS, for both discretization zeros and intrinsic zeros. We develop the theory for sampled-data systems employing a conventional sampler and a zero-order hold together with a single-input single-output continuous-time plant, and then observe that certain results can be extended to the generalized holds. As an application, we establish a condition for sampled-data systems that allow for discrete-time stable inversion-based control where the absence of such an UMS zero is crucial in the design of such control systems. |
2020 |
Jiyeon Nam / Taekyoo Kim / Gyunghoon Park / Hyungbo Shim Weighted Averaged Behavior of Synchronization among Heterogeneous Agents in a Sampled-data Setting Proceedings Article In: Proc. of 2020 Annual American Control Conference (ACC), pp. 4405-4410, IEEE, Denver, CO, USA, 2020. Abstract | Links | BibTeX | Tags: Blended dynamics, Heterogeneous multi-agents, Sampled data system @inproceedings{NamKimParkShim20, In this paper, we address the problem of synchronization among heterogeneous agents in a sampled-data setting. The key observation is that the sample-and-hold process introduces additional node-wise weights on the Laplacian matrix in the discrete-time domain. We then show that in the sampled-data setting, all of the agents' states approach the state of the so-called weighted averaged dynamics, an auxiliary dynamics that represents the collective behavior of heterogeneous agents when they are synchronized. In addition, admissible ranges of the sampling period and the diffusive coupling gain are computed, with which the consensus among the agents is achieved in a practical sense. |
2016 |
Gyunghoon Park / Hyungbo Shim / Kyungchul Kong Can Continuous-time Disturbance be Represented by Sampled Input Disturbance? Proceedings Article In: Proc. of 2016 16th International Conference on Control, Automation and Systems, pp. 1261-1266, IEEE, Gyeongju, Korea, 2016. Abstract | Links | BibTeX | Tags: Continuous-time system, Sampled data system, Stability @inproceedings{ParkShimKong16, Abstract: In this paper, we study whether any continuous-time disturbance to a continuous-time plant can be equivalently represented by a sampled input disturbance to a sampled-data model. With the help of the sampled-data system theory, we show that such equivalent sampled disturbance exists for almost sampling period and even for mismatched continous-time disturbances. Moreover, it is also discussed that whether the equivalent sampled disturbance is bounded significantly depends on the zeros of the sampled-data system. Simulation results verify the validity of the stability analysis. |
List of English Publication
2024 |
On Existence of Uniformly Marginally Stable Zeros of Linear Sampled-data Systems and its Application to Stable Inversion-based Control Journal Article In: IEEE Access, vol. 12, pp. 49826 - 49836, 2024, ISSN: 2169-3536. |
2020 |
Weighted Averaged Behavior of Synchronization among Heterogeneous Agents in a Sampled-data Setting Proceedings Article In: Proc. of 2020 Annual American Control Conference (ACC), pp. 4405-4410, IEEE, Denver, CO, USA, 2020. |
2016 |
Can Continuous-time Disturbance be Represented by Sampled Input Disturbance? Proceedings Article In: Proc. of 2016 16th International Conference on Control, Automation and Systems, pp. 1261-1266, IEEE, Gyeongju, Korea, 2016. |