Safety-function design for the control system of a human-cooperative robot based on functional safety of hardware and software

Suwoong Lee, Yoji Yamada, Kazuhiro Ichikawa, Osamu Matsumoto, Keiko Homma, Eiichi Ono

Research output: Contribution to journalArticlepeer-review

10 Citations (Scopus)


Human-cooperative robots (HCRs) are expected to benefit various fields. Safety functions are essential to the control system of HCRs because their hazardous movements after a system failure may cause serious injuries to operators. Therefore, their reliability must be sufficiently high relative to the estimated risk, and it is important to design a suitable safety function for the control system to match the safety level required for an HCR. We propose a methodology of safety-function design for the control system of an HCR and attempt to effectively combine design approaches for hardware and software of safety-related systems (SRSs) on the basis of the concept of functional safety. This study describes the details of the methodology for an HCR that we adopted as a platform system. First, SRS hardware with a dual-channel voting architecture was designed, and then, functional safety analysis was performed to verify whether the hardware satisfied the required safety integrity level (SIL). Next, SRS software with diverse programming, which is recommended for the required SIL, was designed by utilizing a disturbance observer. Finally, experiments were conducted on the SRS for representative failures and the safety function was verified for the control system, as set by the proposed methodology.

Original languageEnglish
Article number6507654
Pages (from-to)719-729
Number of pages11
JournalIEEE/ASME Transactions on Mechatronics
Issue number2
Publication statusPublished - 2014 Apr
Externally publishedYes


  • Man-machine systems
  • Safety
  • System analysis and design

ASJC Scopus subject areas

  • Control and Systems Engineering
  • Computer Science Applications
  • Electrical and Electronic Engineering


Dive into the research topics of 'Safety-function design for the control system of a human-cooperative robot based on functional safety of hardware and software'. Together they form a unique fingerprint.

Cite this