BILATERAL CONTROL OF MASTER-SLAVE MANIPULATOR
SYSTEM USING TIME DELAY CONTROL
Jong Kwang Lee, Hyo Jik Lee, Byung Suk Park, Seung-Nam Yu, Kiho Kim and Ho Dong Kim
Fuel Cycle System Engineering Development Division, Korea Atomic Energy Research Institute, Daejeon, Korea
Keywords: Time delay control, Master-slave manipulator, Teleoperation.
Abstract: A prototype of dual arm master-slave manipulator system has been developed for use in a hot-cell at Korea
Atomic Energy Research Institute. The slave manipulator can handle a 25 kgf payload in any posture, where
the gravity force of remote tools or handling equipment has a great impact on the position error which
produces the unnecessary force that operator does not have to feel. In this work, we applied a time delay
controller for bilateral teleoperaiton of the manipulator system. Experimental results show that the time
delay controller has good performance of the position tracking as well as force reflection.
1 INTRODUCTION
The use of remotely operated manipulators and other
mechanical devices as replacements for human
workers in hazardous environment is a growing field
of research. In particular, master-slave manipulators
have been extensively used in the nuclear industries
governed by the ALARA principle for more than
five decades. The master manipulator is an input
device which interfaces with a human operator on
one side and with a slave manipulator on the other.
Bilateral force-reflecting control plays a key support
role in a successful dexterous manipulator for
master-slave manipulators. Great increases in the
performance of master-slave manipulator systems
can be achieved through a good design of the
mechanical hardware and a proper implementation
of the embedded control strategies.
Recently, we developed a prototype master-slave
manipulator system for integrated demonstration of
Pyroprocess which is a technology for refining
nuclear materials from spent nuclear fuels using an
electrochemical method in a molten salt bath at high
temperature (Lee, Park, Lee, Kim & Kim, 2010).
The Pyroprocess demonstration facility has a
completely sealed argon gas-filled cell, with
dimensions 40.3 × 4.8 × 6.4 m (L × W × H), where
direct access by human operators is not possible
during operation due to the high toxicity of argon
gas. Therefore, all the operation and maintenance of
process equipment must be performed remotely
through master-slave manipulation.
Position-based bilateral control of master-slave
manipulator system using PD controller has been
mainly applied in the real field teleoperation system
for practical reasons. However, the control
performance will be degraded in case of existence of
disturbances. In the controller, the position error
occurs significantly due to the change of the gravity
force of handling equipments. Therefore, it produces
unnecessary force reflected to an operator owing to
the nature of position error based force reflection.
To achieve a good tracking performance as well
as highly transparent control, we applied Time
Delay Control (TDC) for master-slave teleoperation.
TDC has been proposed as an effective control
method for nonlinear time-varying systems with
unknown dynamics and/or unpredictable
disturbances (Youcef-Toumi and Ito, 1990) and its
stability was proven by Youcef-Toumi (1992) and
Jung, Chang and Kang (2007). Hasia and Gao (1990)
applied TDC to robot position control. Chang, Kim
and Park (2004) used TDC to force/position control
for robot manipulator. Song and Byun (2000)
suggested a time delay controller with a variable
reference model to improve the transient response
characteristics and verified its performance on the
BLDC motor position control. Recently, to
overcome the performance degradation of the TDC
in presence of nonlinear friction, Han and Chang
(2010) proposed TDC with gradient estimator.
In this paper, we applied TDC to bilateral control
of master-slave teleoperation system and verified its
performance through experimental studies. This
37
Lee J., Lee H., Park B., Yu S., Kim K. and Kim H..
BILATERAL CONTROL OF MASTER-SLAVE MANIPULATOR SYSTEM USING TIME DELAY CONTROL.
DOI: 10.5220/0003535800370042
In Proceedings of the 8th International Conference on Informatics in Control, Automation and Robotics (ICINCO-2011), pages 37-42
ISBN: 978-989-8425-75-1
Copyright
c
2011 SCITEPRESS (Science and Technology Publications, Lda.)