• Progress in Superconductivity and Cryogenics
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• v.18 no.1
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• pp.6-9
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• 2016

The history of IFMFC (International Forum on Magnetic Force Control) shows the usefulness of the magnetic force control in the fields of the environment and material resource in Japan, Korea and China. The IFMFC started in 2010 and has been organized in every year. This paper shows the application of the magnetic force control in each countries with the accumulated knowledge and experience of the magnetic force control with IFMFC.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.4
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• pp.122-128
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• 1996

In high speed and high precision assembly systems such as a surface mounting device and robotend effector, the contact force control is required. As the operation repeats, the repetitive control is applied to reduce the periodic contact force errors. Since high order unmodelled dynamics are easily excited in contact force control, a Q filter was introduced and its robust stability was analyzed. Simulation and Experimental results show the effectiveness of the algorithm.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.8
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• pp.801-806
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• 2014

LAS (Laparoscopy Assisted Surgery) has been substituted alternatively for traditional open surgery. However, when using a commercialized robot assisted laparoscopic such as Da Vinci, surgeons have encountered some problems due to having to depend only on information by visual feedback. To solve this problem, a haptic function is required. In order to realize the haptic teleoperation system, a force feedback and bilateral control system are needed. Previous research showed that the perturbation value estimated by a SPO (Sliding Perturbation Observer) followed a reaction force that loaded on the surgical robot instrument. Thus, in this paper, the force feedback problem of surgical robots is solved through the reaction force estimation method. This paper then introduces the possibility of the haptic function realization of a laparoscopic surgery robot using a bilateral control system. For bilateral control, the master uses an impedance control and the slave uses a SMC (Sliding Mode Control). The experiment results show that a torque and force sensorless teleoperation system can be implemented using a bilateral control structure.

• The Journal of Korea Robotics Society
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• v.1 no.1
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• pp.81-88
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• 2006

Control of a robot manipulator in contact with the environment is usually conducted by the direct feedback control using a force-torque sensor or the indirect impedance control. In these methods, however, the control algorithms become complicated and the performance of position and force control cannot be improved because of the mechanical properties of the passive components. To cope with such problems, redundant actuation has been used to enhance the performance of position control and force control. In this research, a Double Actuator Unit (DAU) is proposed, with which the force control algorithm can be simplified and can make the robot ensure the safety during the external collision. The DAU is composed of two actuators; one controls the position and the other modulates the joint stiffness. Using this unit, it is possible to independently control the position and stiffness. The DAU based on the planetary gears is investigated in this paper. Performance using the DAU is also verified by various experiments. It is shown that the manipulator using this mechanism provides better safety during the impact with the environment by reducing the joint stiffness appropriately on detecting the collision of a manipulator.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.11
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• pp.1096-1101
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• 2009

In this paper, an embedded system has been designed for force control application to interact between a robot arm and a human operator. Force induced by the human operator is converted to the desired position information for the robot to follow. For smooth operations, the impedance force control algorithm is utilized to represent interaction between the robot and the human operator by filtering the force. To improve the performance of position control of the robot arm, a velocity term has been obtained and tested by several filters. A PD controller for position control has been implemented on an FPGA as well. Experimental studies are conducted with the ROBOKER to test the functionality of the designed hardware.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.3 s.174
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• pp.653-660
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• 2000

The automatization by industrial robot of today is merely rely on to the simple position repeating works, but requirements of research and development to the force control which would adapt positively to various restriction or contacting works to environment. In this paper, a learning control algorithm using, neural networks is proposed for the position and force control by a direct-drive robot. The proposed controller is the feedback controller to which the learning function of neural network is added on to and has a character of improving controller's efficiency by learning. The effectiveness of the proposed algorithm is demonstrated by the experiment on the hybrid position and force control of a parallelogram link robot with a force sensor.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.130-134
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• 1992

The ability of a robot system to comply to an environment via the control of tool-environment interaction force is of vital for the successful task accomplishment in many robot application. This paper presents the implementation of external force control for two dimensional contour following task using a commercial robot system. Force accommodation is used since a constraint imposed in our work is not to modify the commercial robot system. A linear, decoupled model of two dimensional contour following system in the discrete time domain is derived first. Then the experimental verification of linear control is obtained using a PUMA 560 manipulator with standard Unimation controller, Astek FS6-120A six axis wrist force sensor attached externally to the arm and LSI-11173 microcomputer. Experimentally obtained data shows that the RMS contact force error is 0.8246 N when following the straight edge and 2.3768 N when following 40 mm radius curved contour.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.408-411
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• 1995

In this paper, we discuss the force control of flexible manipulators. Since the force control of flexible manipulators with planar one or two links using the distributed-parameter modeling has been the subject of a considerable number of publications until now, real time computations of the force control schemes are possible. But, application of those control schemes to multi-link spatial manipulators is fairly complicated. In this paper, we apply a concise hybrid position/force control scheme for a flexible manipulators. We use a lumped-parameter modeling for the flexible manipulators. The Hamilton's principle is applied to derive the equations of motion for the system and then, state-space model is obtained by the Lagrange's method. Finally, comparison of simulation results with experimental results is given to show the performance of our method.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.12
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• pp.1034-1039
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• 2016

This paper presents the implementation and control of a small-scaled excavator system. The commercial miniature of an excavator system has been modified and its control hardware is embedded to access the feedback control. Encoder sensors are attached to the joint and a force sensor is mounted on the end-effector so that feedback position control is accessible as well as force control. The dynamic model of the excavator system is derived as a four linkage robot arm and its control performances are simulated. Experimental studies of contact force control tasks are conducted to test the control algorithm for the excavator system.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.552-555
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• 1996

In this paper, we present a force control of a five-axes robot, using an impedance model. Tasks such as assembly, grinding, and deburring, which involve extensive contact with the environment, are better handled by controlling the forces of interaction between the manipulator and the environment. The five-link articulated robot is equipped with a wrist force sensor which consists of an array of strain gauges and can delineate the three components of the vector force along the three axes of the sensor coordinate frame, and the three components of the torque about these axes. For the precise control of the contact force, impedance models of a robot and the environment are defined. Experimental results are shown.