PMID- 31973899
OWN - NLM
STAT- PubMed-not-MEDLINE
LR  - 20200608
IS  - 1879-2022 (Electronic)
IS  - 0019-0578 (Linking)
VI  - 101
DP  - 2020 Jun
TI  - Digital implementation of a continuous-time nonlinear optimal controller: An 
      experimental study with real-time computations.
PG  - 346-357
LID - S0019-0578(20)30020-3 [pii]
LID - 10.1016/j.isatra.2020.01.020 [doi]
AB  - In this paper, the digital implementation of a continuous-time robust nonlinear 
      optimal controller is presented as an experimental study with real-time 
      computations. Complicated computations, solutions, and algorithms of nonlinear 
      optimal policies were always reported as limits to experimental implementations. 
      This work uses a combination of integral sliding mode control (ISMC) and the 
      state-dependent Riccati equation (SDRE) approach for controlling an experimental 
      setup, a rotary inverted pendulum (RIP) with nonlinear dynamics. Designing in the 
      continuous-time domain and performing an experiment using digital computers are 
      common and that leads to extra tuning in practice. Digital components are 
      considered in simulations to provide a more real output and omit extra tuning. 
      Analysis of sampling time effect on instability of a stable controller was done 
      and the obtained bound of sampling time was verified in the experiment. The 
      experimental study showed that the computations of the proposed controller were 
      able to be programmed into the platform interface with time-varying sampling time 
      which was bounded to the generated sampling time in the simulation. Successful 
      swinging up and stabilization of the RIP demonstrated the effectiveness of the 
      ISMC plus SDRE approach. The comparison of the proposed controller with the solo 
      SDRE controller validated the results and showed the performance of the design.
CI  - Copyright (c) 2020 ISA. Published by Elsevier Ltd. All rights reserved.
FAU - Nekoo, Saeed Rafee
AU  - Nekoo SR
AD  - Independent Researcher, Tehran, Iran. Electronic address: saerafee@yahoo.com.
LA  - eng
PT  - Journal Article
DEP - 20200120
PL  - United States
TA  - ISA Trans
JT  - ISA transactions
JID - 0374750
SB  - IM
OTO - NOTNLM
OT  - Digital control
OT  - Experimental study
OT  - ISMC
OT  - Rotary inverted pendulum
OT  - SDRE
COIS- Declaration of Competing Interest The authors declare that they have no known 
      competing financial interests or personal relationships that could have appeared 
      to influence the work reported in this paper.
EDAT- 2020/01/25 06:00
MHDA- 2020/01/25 06:01
CRDT- 2020/01/25 06:00
PHST- 2018/05/17 00:00 [received]
PHST- 2020/01/13 00:00 [revised]
PHST- 2020/01/13 00:00 [accepted]
PHST- 2020/01/25 06:00 [pubmed]
PHST- 2020/01/25 06:01 [medline]
PHST- 2020/01/25 06:00 [entrez]
AID - S0019-0578(20)30020-3 [pii]
AID - 10.1016/j.isatra.2020.01.020 [doi]
PST - ppublish
SO  - ISA Trans. 2020 Jun;101:346-357. doi: 10.1016/j.isatra.2020.01.020. Epub 2020 Jan 
      20.