• 제어로봇시스템학회:학술대회논문집
• /
• 1997.10a
• /
• pp.1692-1695
• /
• 1997

In this paper, a new control scheme for master-slave control of telerobot is proposed. The porposed method can be classified into unilater master-slave control methods in the aspect of the data flow. But the master arm in the proposed control scheme can deliver operator the similar kinesthetic sense as other bilateral force reflecting master arms do. The principle concept is that the sensed operator's force/torque is used as the reference input for a damping controller type of telerobot controller which track the operators efforts. Master arm and master controller can be implemented in a simple form, and it needs not be driven by actuators, but force sensing capability.

• Proceedings of the KIEE Conference
• /
• 1991.07a
• /
• pp.795-798
• /
• 1991

The hybrid positon/force control is required when two or more robots perform a coorperative task in a uncertain environment, or when single robot does a task with a constant force to the environment. In this paper, a new control algorithm which control simultaneously the position and the force are proposed, however, especially the conventional position controller employed in the present robot control is used. Moreover, in order to improve the output response characteristics of the system, the PI gains which were computed from the PI gain tunning techniques, are varied based on the results of the Fuzzy algorithm.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.5 no.3
• /
• pp.36-51
• /
• 1995

An approach to robot hybrid position/force control, which allows force manipulations to be realized without overshoot and overdamping while in the presence of unknown environment, is given in this paper. The manin idea is to used dynamic compensation for known robot parts and fuzzy compensation for unknown environment so as to improve system performance. The fuzzy compensation is implemented by using rule based fuzzy approach to identify the unknown environment. The establishment of proposed control system consists of following two stages. First, similar to the resovled acceleration control method, dynamic compensation and PD control based on known robot dynamics, kinematics and estimated environment stiffness is introduced. To avoid overshoot the whole control system is constructed with overdamping. In the second stage, the unknown environment stiffness is identified by using fuzzy reasoning, where the fuzzy compensation rules are obtained priori as the expression of the relationship betweenenvironment stiffness and system. Based on the simulation result, comparison between cases with or without fuzzy identifications are given, which illustrate the improvement achieced.

• Proceedings of the KIEE Conference
• /
• 1989.07a
• /
• pp.693-697
• /
• 1989

In this paper, force control for a multi-legged walking robot is investigated. For stable but relatively rapid walking, a simple force control algorithm is proposed in conjunction with the position control system. The proposed control method is tested on an experimental one leg system of two degree of freedom with a force controller using a position controller and a monoboard microcomputer to implement the proposed control algorithm. The experimental results shows that the control algorithm can be applied for walking in a terrain with wide range variation.

• Journal of the Korean Society for Precision Engineering
• /
• v.22 no.7 s.172
• /
• pp.102-111
• /
• 2005

In this paper, we address a position control for a parallel stage, which is levitated and driven by electric magnetic force. This consists of a levitating object (called platen) with 4 permanent magnetic linear synchronous motors in parallel. Each motor generates vertical force for suspension against gravity and propulsion force horizontally as well. This stage can generate six degrees of freedom motion by the vertical and horizontal force. A dynamic equation of the stage system is derived based on Newton-Euler method and it's special Jacobian matrix describing a relation between the limited velocity and Cartesian velocity is done. There are proposed two control methods for positioning which are Cartesian space controller and Actuator space controller. The control performance of the Cartesian space controller is better than the Actuator space controller in task space trajectory while the Actuator space controller is simpler than the Cartesian space controller in controller realization.

• Journal of Institute of Control, Robotics and Systems
• /
• v.13 no.12
• /
• pp.1207-1212
• /
• 2007

We propose a haptic interface algorithm for joystick operators working in remote control systems of unmanned vehicles. The haptic interface algorithm is implemented using a force-feedback joystick, which is equipped with low price DC motors without encoders. Generating specific amounts of forces on the joystick pole according to the distance between a remote controlled vehicle and obstacles, the haptic interface enables the operator to perceive the distance information by the sense of touch. For the case of no joystick operation or no obstacles in the working area, we propose an origin control algorithm, which positions the joystick pole at the origin. The origin control algorithm prevents the false movement of the remote vehicles and provides the operator with a realistic force resisting the joystick pole's movement. The experiment results obtained under various scenarios exemplify the validity of the proposed haptic interface algorithm and the origin control algorithm.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.63 no.10
• /
• pp.1428-1433
• /
• 2014

In this paper, we propose the formation control algorithm using the leader-following robots in given space. The proposed method is as follows: First, we plan a path of the leader robot for the obstacle avoidance. After that, we propose the formation control algorithm of the following robots using the position and the orientation angle of the leader robot. Also, we propose method for adjusting the formation of the swarm robots when the following robots detect an obstacles. Finally, we show the effectiveness and feasibility of the proposed method though some simulations.

• Journal of Electrical Engineering and Technology
• /
• v.11 no.4
• /
• pp.1042-1048
• /
• 2016

This paper presents a lateral displacement restoring force control for the independently rotating wheelsets (IRWs) of shallow-depth subway systems. In the case of the near surface transit, which has recently been introduced, sharp curved driving performance is required for the city center service. It is possible to decrease the curve radius and to improve the performance of the straight running with the individual torque control. Therefore, the individual torque control performance of the motor is the most important point of the near surface transit. This paper deals with a lateral displacement restoring force control for sharp curved driving. The validity and usefulness of the proposed control algorithm is verified by experimental results using a small-scale bogie system.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.290-295
• /
• 2005

Hydraulic actuators are important in modern industry due to high power, fast response, and high stiffness. In recent years, hybrid actuation system, which combines electric and hydraulic technology in a compact unit, can be adapted to a wide variety of force, speed and torque requirements. Moreover, the hybrid actuation system has dealt with the energy consumption and noise problem existed in the conventional hydraulic system. Therefore, hybrid actuator has a wide range of application fields such as plastic injection-molding and metal forming technology, where force or pressure control is the most important technology. In this paper, the solution for force control of hybrid system is presented. However, some limitations still exist such as deterioration of the performance of transient response due to the variable environment stiffness. Therefore, intelligent switching control using Learning Vector Quantization Neural Network (LVQNN) is newly proposed in this paper in order to overcome these limitations. Experiments are carried out to evaluate the effectiveness of the proposed algorithm with large variation of stiffness of external environment. In addition, it is understood that the new system has energy saving effect even though it has almost the same response as that of valve controlled system.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.18 no.10
• /
• pp.2554-2566
• /
• 1994

Robot position/force control has been a difficult task owing to the interaction between a robot and an environment with a rather high stiffness. In addition to the dynamic instability, the interaction causes the following problem : 1) chattering at steady-state, 2) dynamic coupling effect of robot, and 3) performance degradation due to a titled environment. To solve the problem, the Time Delay Control(TDC), which has been known to be quiet robust to plant uncertainties and disturbances, has been applied. In conjunction to TDC, the following three ideas were also used : 1) To reduce the amplitude of the chattering at the steady state, a novel scheme was adopted to enhance the resolution type solution of A/D conversion for the force sensor. 2) To reduce the dynamic coupling, a trajectory type position command was tried on a comparative basis to the step command, as well as a more accurate mass matrix was used instead of the constant mass matrix. 3) And finally to improve the performance in the tilted environment, force derivatives instead of position derivatives were used in the TDC law. Computer simulations and experiments resulted in obvious improvements on the quality of the hybrid control, thereby clearly demonstrating the effectiveness of TDC with the proposed ideas.