PMID- 25037321
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20150417
LR  - 20150302
IS  - 1879-2022 (Electronic)
IS  - 0019-0578 (Linking)
VI  - 54
DP  - 2015 Jan
TI  - Finite-time state-dependent Riccati equation for time-varying nonaffine systems: 
      rigid and flexible joint manipulator control.
PG  - 125-44
LID - S0019-0578(14)00126-8 [pii]
LID - 10.1016/j.isatra.2014.06.006 [doi]
AB  - This article investigates finite-time optimal and suboptimal controls for 
      time-varying systems with state and control nonlinearities. The state-dependent 
      Riccati equation (SDRE) controller was the main framework. A finite-time 
      constraint imposed on the equation changes it to a differential equation, known 
      as the state-dependent differential Riccati equation (SDDRE) and this equation 
      was applied to the problem reported in this study that provides general 
      formulation and stability analysis. The following four solution methods were 
      developed for solving the SDDRE; backward integration, state transition matrix 
      (STM) and the Lyapunov based method. In the Lyapunov approach, both positive and 
      negative definite solutions to related SDRE were used to provide suboptimal gain 
      for the SDDRE. Finite-time suboptimal control is applied for robotic manipulator, 
      as finite-time constraint strongly decreases state error and operation time. 
      General state-dependent coefficient (SDC) parameterizations for rigid and 
      flexible joint arms (prismatic or revolute joints) are introduced. By including 
      nonlinear control inputs in the formulation, the actuator׳s limits can be 
      inserted directly to the state-space equation of a manipulator. A finite-time 
      SDRE was implemented on a 6R manipulator both in theory and experimentally. And a 
      reduced 3R arm was modeled and tested as a flexible joint robot (FJR). 
      Evaluations of load carrying capacity and operation time were investigated to 
      assess the capability of this approach, both of which showed significant 
      improvement.
CI  - Copyright (c) 2014 ISA. Published by Elsevier Ltd. All rights reserved.
FAU - Korayem, M H
AU  - Korayem MH
AD  - Robotic Research Laboratory, School of Mechanical Engineering, Iran University of 
      Science and Technology (IUST), 1684613114 Tehran, Iran.
FAU - Nekoo, S R
AU  - Nekoo SR
AD  - Robotic Research Laboratory, School of Mechanical Engineering, Iran University of 
      Science and Technology (IUST), 1684613114 Tehran, Iran. Electronic address: 
      rafee@iust.ac.ir.
LA  - eng
PT  - Journal Article
DEP - 20140716
PL  - United States
TA  - ISA Trans
JT  - ISA transactions
JID - 0374750
OTO - NOTNLM
OT  - Finite-time
OT  - Flexible joint robot
OT  - Manipulator control
OT  - Nonlinear
OT  - Optimal
OT  - SDDRE
OT  - SDRE
EDAT- 2014/07/20 06:00
MHDA- 2014/07/20 06:01
CRDT- 2014/07/20 06:00
PHST- 2014/05/02 00:00 [received]
PHST- 2014/05/30 00:00 [revised]
PHST- 2014/06/15 00:00 [accepted]
PHST- 2014/07/20 06:00 [entrez]
PHST- 2014/07/20 06:00 [pubmed]
PHST- 2014/07/20 06:01 [medline]
AID - S0019-0578(14)00126-8 [pii]
AID - 10.1016/j.isatra.2014.06.006 [doi]
PST - ppublish
SO  - ISA Trans. 2015 Jan;54:125-44. doi: 10.1016/j.isatra.2014.06.006. Epub 2014 Jul 
      16.