Tracking Controller Design of Omnidirectional Mobile Manipulator System

Nguyen Hung,Dae-Hwan Kim,Hak-Kyeong Kim,Sang-Bong Kim 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8

This paper proposed a tracking controller for an omnidirectional mobile manipulator system, a three-linked manipulator mounted on a three-wheeled omnidirectional mobile platform, to track a desired trajectory with constant desired velocity. An end-effector mounted at the end of a manipulator of the omnidirectional mobile manipulator system is controlled to track a desired trajectory with constant desired velocity. A distributed control method is applied to control the omnidirectional mobile manipulator system that includes two subsystems such as an omnidirectional mobile platform and a manipulator. Two controllers are designed to control two subsystems, respectively. Firstly, based on a tracking error vector between a point of the end-effector and a reference point, a kinematic controller is designed for the end-effector of the manipulator to track a reference point. Secondly, based on a tracking error vector between a target point and a real point of the end-effector, a sliding mode controller based on its dynamic model is designed for the omnidirectional mobile platform to move so that the manipulator tracks the desired posture without its singulariry. The control laws are obtained based on backstepping technique and make the tracking error vectors go to zero asymtotically. The system stability is proved using the Lyapunov stability theory. The simulation results are presented to illustrate the usefulness of the proposed control scheme in the presence uncertainties and external disturbances.

Decoupling Control of 2-link Manipulator with Model Following Control and Proposed Control Gains Design (ICCAS 2012)

Linfeng Lan,Kousuke Okabe,Ryuichi Oguro,Hideki Honda 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

In this paper, a new decoupling control scheme of 2-link industrial manipulator with application of the model following control has been proposed. Compensation torque used for removing interference force between two arms of the manipulator has been designed in feed-forward control loop. Compared with the conventional scheme, the proposed scheme is more simple and realistic to be taken in to practice for general purpose controllers. And, a new design consideration for control gains has also been shown. Moreover, disturbance observer is applied to cope with model error problem in feed-back control loop. Effectiveness of the proposed decoupling control scheme has been confirmed through simulation results.

무게중심위치와 슬라이딩 모드 제어를 통한 이륜형 모바일 머니퓰레이터의 자세제어

김민규,우창준,이장명,Kim, Min-Gyu,Woo, Chang-Jun,Lee, Jangmyung 제어로봇시스템학회 2015 제어·로봇·시스템학회 논문지 Vol.21 No.8

This paper proposes an attitude control system to keep the balance for a two-wheeled mobile manipulator which consists of a mobile platform and a three D.O.F. manipulator. In the conventional control scheme, complicated dynamics of the manipulator need to be derived for balancing control of a mobile manipulator. The method proposed in this paper, however, three links are considered as one body of mass and the dynamics are derived easily by using an inverted pendulum model. One of the best advantage of a sliding mode controller is low sensitivity to plant parameter variations and disturbances, which eliminates the necessity of exact modeling to control the system. Therefore the sliding mode control algorithm has been adopted in this research for the attitude control of mobile platform along the pitch axis. The center of gravity for the whole mobile manipulator is changing depending on the motion of the manipulator. And the orientation variation of center of gravity is used as reference input for the sliding mode controller of the pitch axis to maintain the center of gravity in the middle of robot to keep the balance for the robot. To confirm the performance of controller, MATLAB Simulink has been used and the resulting algorithms are applied to a real robot to demonstrate the superiority of the proposed attitude control.

Implementation and Comparison of Controllers for Planar Robots

John Kern,Claudio Urrea,Hugo Torres 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.2

The nonlinear behavior and the high performance requirement are the main problems that appear in the design of manipulator robots and their controllers. For that reason, the simulation, realtime execution and comparison of the performance of controllers applied to a robot with three degrees of freedom are presented. Five controllers are prepared to test the robot"s dynamic model: predictive; hyperbolic sine-cosine; sliding mode; hybrid composed of a predictive + hyperbolic sine-cosine controller; and adaptive controller. A redundant robot, a communication and signal conditioning interface, and a simulator are developed by means of the MatLab/Simulink software, which allows analyzing the dynamic performance of the robot and of the designed controllers. The manipulator robot is made to follow a test trajectory which, thanks to the proposed controllers, it can do. The results of the performance of this manipulator and of its controllers, for each of the three joints, are compared by means of RMS indices, considering joint errors according to the imposed trajectory and to the controller used.

원격 와이핑 작업을 위한 제어 기법

전지명,이승호,문일동,오재윤 전북대학교 공학연구원 ( 구 전북대학교 공업기술연구소 ) 2002 工學硏究 Vol.33 No.-

This study proposes a technique utilizing virtual information instead of real information in a teleoperated wiping operation. A teleoperation system composed of a master manipulator, a slave manipulator, and a real-time control system is used for this study. Both the master and slave manipulator have a kinematic structure effectively conveying and following the operator’s command respectively. The master manipulator uses DC servo motors to do a major role for counter balancing. A force sensor attached at the end of the slave manipulator’s end effector is used to measure a contact force. MATLAB/xPC Target is used for real-time control of the teleoperation system in Windows OS. This study proposes algorithms for generating the virtual force and the virtual velocity. They are generated as the master manipulator’s grip moves up and down, and back and forth. A force-force control technique proposing in this paper uses the virtual force as a reference input for the contact force control, and uses the virtual velocity as a reference input for control the slave manipulator’s horizontal movement. A PID controller is used as a local controller for the contact force control. In order to show the effectiveness of the proposing force-force control technique, experiments are performed on a plastic plate with two bumps.

Simultaneous precision positioning and vibration suppression of reciprocating flexible manipulators

Ma, Kougen,Ghasemi-Nejhad, Mehrdad N. Techno-Press 2005 Smart Structures and Systems, An International Jou Vol.1 No.1

Simultaneous precision positioning and vibration suppression of a reciprocating flexible manipulator is investigated in this paper. The flexible manipulator is driven by a multifunctional active strut with fuzzy logic controllers. The multifunctional active strut is a combination of a motor assembly and a piezoelectric stack actuator to simultaneously provide precision positioning and wide frequency bandwidth vibration suppression capabilities. First, the multifunctional active strut and the flexible manipulator are introduced, and their dynamic models are derived. A control strategy is then proposed, which includes a position controller and a vibration controller to achieve simultaneous precision positioning and vibration suppression of the flexible manipulator. Next, fuzzy logic control approach is presented to design a fuzzy logic position controller and a fuzzy logic vibration controller. Finally, experiments are conducted for the fuzzy logic controllers and the experimental results are compared with those from a PID control scheme consisting of a PID position controller and a PID vibration control. The comparison indicates that the fuzzy logic controller can easily handle the non-linearity in the strut and provide higher position accuracy and better vibration reduction with less control power consumption.

State Control of a 12 DOF Mobile Manipulator via Centroid Feedback

Gang Wang,이장명 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

This paper presents a method for controlling the time-varying centroid of a two-wheeled mobile manipulator via centroid feedback. The state control of a two-wheeled mobile manipulator is a typical example of the stable control of a nonlinear time-varying system. Because of the principle of the two-wheeled inverted pendulum robot, when the centroid of the mobile manipulator changes, the state of the mobile manipulator changes. To control the state of the mobile manipulator, the centroid of the mobile manipulator must be kept at a vertical position. The position of the centroid of the mobile manipulator can be obtained in Cartesian space via coordinate transformation. The position data are then fed back to the mobile platform for achieving state control of the mobile manipulator. Through simulations, the centroid feedback control is combined with a basic PD control, which completes the state control of the mobile manipulator. The experimental data demonstrate the effectiveness of the proposed method in achieving state control of a 12DOF mobile manipulator

Balancing control of Mobile Manipulator with Sliding mode Controller

Yudong Zhao,Changjun Woo,Jangmyung Lee 제어로봇시스템학회 2015 제어로봇시스템학회 국제학술대회 논문집 Vol.2015 No.10

This paper proposes an attitude control system to keep the balance of a two-wheeled mobile manipulator which consists of a mobile platform and a three D.O.F. manipulator. In the conventional control scheme, complicated dynamics is utilized for balancing control of a mobile manipulator. In this paper, however, three links are considered as one body and the dynamics is derived easily by using inverted pendulum model. sliding mode controller is characterized as low sensitivity to plant parameter uncertainties and disturbances and non-necessity of an explicit model of the system. Therefore, it is adopted in this research for the attitude control of mobile platform with respect to the pitch axis. The center of gravity for the whole mobile manipulator is changing along with the motion of the manipulator. And the orientation variation of center of gravity is used as reference input for the sliding mode controller to maintain the center of gravity in the middle of robot so that the whole system can keep balance. To confirm the performance of the controller proposed in this paper, MATLAB Simulink has been used and an experiment is carried out to demonstrate the superiority of the proposed attitude control.

다관절 머니퓰레이터의 사용자 중심 제어기 설계

손현석,강대훈,이장명,Son, HeonSuk,Kang, DaeHoon,Lee, JangMyung 대한임베디드공학회 2008 대한임베디드공학회논문지 Vol.3 No.2

This paper proposes a PC-based open architecture controller for a multi-axis robotic manipulator. The designed controller can be applied for various multi-axes robotic manipulators since the motion controller is implemented on a PC with its peripheral devices. The accuracy of the controller based on the computed torque method has been measured with the dynamic model of manipulator. Since the controller is implemented in the PC-based architecture, it is free from the user circumstances and the operating environment. Dynamics of the manipulator have been compensated by the feed forward path in the inner loop and the resulting linear outer loop has been controlled by PD algorithm. Using the specialized language, it can be more efficient in programming and in driving of the multi-axis robot. Unlike the conventional controller that is used to control only a specific robot, this controller can be easily changed for various types of robots. This paper proposes a PC-based controller that has a simple architecture with its simple interface circuits than general commercial controllers. The maintenance and the performance of the controller can be easily improved for a specific robot. In fact, using a Samsung multi-axis robot, AT1, the controller performance and convenience of the PC-based controller have been verified by comparing to the commercial one.

Modeling, Identification and Control of a Redundant Planar 2-DOF Parallel Manipulator

Yao-Xin Zhang,Shuang Cong,Wei-Wei Shang,Ze-Xiang Li,Shi-Long Jiang 대한전기학회 2007 International Journal of Control, Automation, and Vol.5 No.5

In this paper, the dynamic controller design problem of a redundant planar 2-dof parallel manipulator is studied. Using the Euler-Lagrange equation, we formulate the dynamic model of the parallel manipulator in the joint space and propose an augmented PD controller with forward dynamic compensation for the parallel manipulator. By formulating the controller in the joint space, we eliminate the complex computation of the Jacobian matrix of joint angles with end-effector coordinate. So with less computation, our controller is easier to implement, and a shorter sampling period can be achieved, which makes the controller more suitable for high-speed motion control. Furthermore, with the combination of static friction model and viscous friction model, the active joint friction of the parallel manipulator is studied and compensated in the controller. Based on the dynamic parameters of the parallel manipulator evaluated by direct measurement and identification, motion control experiments are implemented. With the experiments, the validity of the dynamic model is proved and the performance of the controller is evaluated. Experiment results show that, with forward dynamic compensation, the augmented PD controller can improve the tracking performance of the parallel manipulator over the simple PD controller.