Delay-Induced Coexistence of Attractors in a Controlled Drill-String

Ibukunolu O. Oladunjoye, James Ing, Sumeet S. Aphale

Research output: Chapter in Book/Report/Conference proceedingPublished conference contribution


The realistic modeling and effective control of drill-strings has been an ongoing research challenge. This has recently come to focus due to the volatility in the oil industry. Owing to the severely nonlinear nature of the drill-string, evolved nonlinear control techniques have recently been proposed to overcome the inherent stick-slip dynamics which are severely detrimental to the drilling performance as well as structural health of any given drill-string. Yet, most of the controller performance is analysed without including the significant delay intrinsic to the overall system. In this paper, the impact of system delay on
the overall performance of a controlled drill-string is studied via extensive
simulations. The analysis presents the impact of delay on three recently proposed sliding-mode control schemes. A surprising coexistence of attractors is observed from the delayed system on the third controller. This result will potentially impact the design of implementable control schemes proposed in future.
Original languageEnglish
Title of host publicationModeling, Design and Simulation of Systems
Subtitle of host publicationAsiaSim 2017, Part 1
EditorsMohamed Sultan Mohamed Ali, Herman Wahid, Nurul Adilla Mohd Subha, Shafishuhaza Sahlan, Mohd Amri Md. Yunus, Ahmad Ridhwan Wahap
Place of PublicationSingapore
Number of pages13
ISBN (Electronic)9789811064630
ISBN (Print)9789811064623
Publication statusPublished - 26 Aug 2017
Event17th Asia Simulation Conference - Meleka, Malaysia
Duration: 27 Aug 201729 Aug 2017

Publication series

NameCommunications in Computer and Information Science (CCIS)
ISSN (Print)1865-0929
ISSN (Electronic)1865-0937


Conference17th Asia Simulation Conference
Abbreviated titleAsiaSim 2017


  • Drill-string dynamics
  • Stick-slip oscillation
  • Coexistence
  • Attractors
  • Sliding-mode controller
  • Delay


Dive into the research topics of 'Delay-Induced Coexistence of Attractors in a Controlled Drill-String'. Together they form a unique fingerprint.

Cite this