Integrated SolidWorks & Simscape Platform for the Model-Based Control Algorithms of Hydraulic Manipulators

Ahn, Doo Sung,Lee, Ill Yeong,Kim, Hyun Ho The Korean Society for Fluid Power and Constructio 2015 드라이브·컨트롤 Vol.12 No.4

Hydraulic manipulators have been widely used in many different fields due to their high force/torque to inertia ratio. The increased speed of hydraulic manipulators requires solutions to problems ranging from mechanical design to the need to determine a robot model suitable for model-based control. As a solution, this paper presents the integration of SolidWorks with Simscape for designing and controlling hydraulic manipulators. The integration provides a platform for the rapid control prototyping of a hydraulic robot without the need to build actual prototypes. The mechanical drawings of a manipulator are first created using Solidworks and are then imported into Simscape, where the manipulator is represented by connected block diagrams based on the principle of physical modeling. Simulation examples for a 3D manipulator made by KNR SYSTEM INC are verified to show the effectiveness of the presented platform.

Integrated SolidWorks & Simscape Platform for the Model-Based Control Algorithms of Hydraulic Manipulators

Doo Sung Ahn,Ill Yeong Lee,Hyun Ho Kim 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.4

Hydraulic manipulators have been widely used in many different fields due to their high force/torque to inertia ratio. The increased speed of hydraulic manipulators requires solutions to problems ranging from mechanical design to the need to determine a robot model suitable for model-based control. As a solution, this paper presents the integration of SolidWorks with Simscape for designing and controlling hydraulic manipulators. The integration provides a platform for the rapid control prototyping of a hydraulic robot without the need to build actual prototypes. The mechanical drawings of a manipulator are first created using Solidworks and are then imported into Simscape, where the manipulator is represented by connected block diagrams based on the principle of physical modeling. Simulation examples for a 3D manipulator made by KNR SYSTEM INC are verified to show the effectiveness of the presented platform.

Integrated SolidWorks & Simscape Platform for the Model-Based Control Algorithms of Hydraulic Manipulators

안두성,이일영,김현호 사단법인 유공압건설기계학회 2015 드라이브·컨트롤 Vol.12 No.4

Hydraulic manipulators have been widely used in many different fields due to their high force/torque to inertia ratio. The increased speed of hydraulic manipulators requires solutions to problems ranging from mechanical design to the need to determine a robot model suitable for model-based control. As a solution, this paper presents the integration of SolidWorks with Simscape for designing and controlling hydraulic manipulators. The integration provides a platform for the rapid control prototyping of a hydraulic robot without the need to build actual prototypes. The mechanical drawings of a manipulator are first created using Solidworks and are then imported into Simscape, where the manipulator is represented by connected block diagrams based on the principle of physical modeling. Simulation examples for a 3D manipulator made by KNR SYSTEM INC are verified to show the effectiveness of the presented platform.

Adaptive sliding mode control with backstepping technique for hydraulic manipulator

Duc-Thien Tran,Hoai Vu Anh Truong,Xuan Dinh To,Bomoon Seo,Kyoung Kwan Ahn 제어로봇시스템학회 2018 제어로봇시스템학회 국내학술대회 논문집 Vol.2018 No.5

In this paper, an adaptive sliding mode control with backstepping technique is proposed regarding to controlling position of a hydraulic manipulator in joint space. The proposed control is developed based on sliding mode control, backstepping technique, and radial basis function neural network (RBFNN). In the hydraulic manipulator, the primary torques are generated by hydraulic actuators, so it helps to extend load carrying capacity of the manipulator. But it brings some challenges, such as coupling issues, uncertainties in parameter, modeling, and external disturbance in mechanical and hydraulic dynamics. The properties of the proposed control can deal to these problems to guarantee the stability requirements and improve the precision. The sliding mode control with backstepping technique is used to handle the coupling issues and to ensure the stability and robustness. Additionally, two adaptive approximators based on RBFNN compensate the uncertainties and improve the precision. Some simulations are implemented and compared to other controllers to exhibit the effectiveness of the proposed control.

Adaptive neural network sliding mode control for serially connected hydraulic cylinders of a heavy-duty hydraulic manipulator

Xinping Guo,Hengsheng Wang,Liang Wang,Hua Liu 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.7

A sliding mode control based on adaptive neural network is proposed aiming at the automatic control problem of the heavy-duty hydraulic manipulator, which is widely applied in construction machinery. The simplified state space model is established for the two hydraulic cylinders connected in series for the parallel movement of the boom of a rock drilling jumbo manipulator. By using the square of the norm of the neural network weight vector to replace the elements of the weight vector as the adaptive parameter, the computational burden of the controller is reduced and hence becomes more suitable for practical applications. The control law is designed by combining adaptive neural network with sliding mode control, and Lyapunov stability analysis is performed theoretically for the proposed control algorithm. Simulations are conducted to verify the feasibility of the designed controller. Extensive experimental studies are carried out on the heavy-duty hydraulic manipulator of a rock drilling jumbo. When tracking sinusoidal position, the error of the proposed controller is reduced by 53 % and 71 % compared with the traditional sliding mode controller and PID controller, respectively, thereby proving the effectiveness and practicality of the proposed control algorithm.

Design and Experimental Evaluation of a Robust Force Controller for a 6-Link Electro-Hydraulic Manipulator via H$_{\infty}$ Control Theory

Ahn, Kyoung-Kwan,Lee, Byung-Ryong,Yang, Soon-Yong The Korean Society of Mechanical Engineers 2003 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.17 No.7

Uninterrupted power supply has become indispensable during the maintenance task of active electric power lines as a result of today's highly information-oriented society and increasing demand of electric utilities. This maintenance task has the risk of electric shock and the danger of falling from high place. Therefore it is necessary to realize an autonomous robot system using electro-hydraulic manipulators because hydraulic manipulators have the advantage of electric insulation and power/mass density. Meanwhile an electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and its parameter fluctuations are greater than those of an electrically driven manipulator. So it is relatively difficult to realize not only stable contact work but also accurate force control for the autonomous assembly tasks using hydraulic manipulators. In this paper, the robust force control of a 6-link electro-hydraulic manipulator system used in the real maintenance task of active electric lines is examined in detail. A nominal model for the system is obtained from experimental frequency responses of the system, and the deviation of the manipulator system from the nominal model is derived by a multiplicative uncertainty. Robust disturbance observers for force control are designed using this information in an H$\_$$\infty$/ framework, and implemented on the two different setups. Experimental results show that highly robust force tracking by a 6-link electro-hydraulic manipulator could be achieved even if the stiffness of environment and the shape of wall change.

3축 전기유압 매니퓰레이터의 컴플라이언스 제어

안경관(Kyoung Kwan Ahn),표성만(Sung Man Pyo) Korean Society for Precision Engineering 2004 한국정밀공학회지 Vol.21 No.1

An electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and its parameter fluctuations are greater than those of an electrically driven manipulator. So it is relatively difficult to obtain stable control performance. In this report, we applied disturbance estimation and compensation type robust control to all axes in a 3 -link electro￢hydraulic manipulator. From the results of experiment, it was confirmed that the performance of trajectory tracking and attitude regulating is greatly improved by the disturbance observer, which model is the same for each axis. On the other hand, for the autonomous assembly tasks, it is said that compliance control is one of the most available methods. Therefore we proposed compliance control which is based on the position control by disturbance observer for our manipulator system. To realize more stable contact work, the states in the compliance loop are feedback, where not only displacement but also velocity and acceleration are considered. And we applied this compliance control to Peg-in-Hole insertion task and analyzed mechanical relation between peg and hole. Also we proposed new method of shifting the position of end-effector periodically for the purpose of smooth insertion. As a result of using this method, it is experimentally confirmed that Peg-in-Hole insertion task with a clearance of 0.05[mm] can be achieved.

RGB-D 센서, AR 마커, 색수정 알고리즘을 활용한 매니퓰레이터 투명화

김동엽,김영지,손현식,황정훈 한국로봇학회 2020 로봇학회 논문지 Vol.15 No.3

The purpose of our sensor system is to transparentize the large hydraulic manipulators of a six-ton dual arm excavator from the operator camera view. Almost 40% of the camera view is blocked by the manipulators. In other words, the operator loses 40% of visual information which might be useful for many manipulator control scenarios such as clearing debris on a disaster site. The proposed method is based on a 3D reconstruction technology. By overlaying the camera image from front top of the cabin with the point cloud data from RGB-D (red, green, blue and depth) cameras placed at the outer side of each manipulator, the manipulator-free camera image can be obtained. Two additional algorithms are proposed to further enhance the productivity of dual arm excavators. First, a color correction algorithm is proposed to cope with the different color distribution of the RGB and RGB-D sensors used on the system. Also, the edge overlay algorithm is proposed. Although the manipulators often limit the operator’s view, the visual feedback of the manipulator’s configurations or states may be useful to the operator. Thus, the overlay algorithm is proposed to show the edge of the manipulators on the camera image. The experimental results show that the proposed transparentization algorithm helps the operator get information about the environment and objects around the excavator.

웨어러블 조작기 기반 유압 구동 6축 다관절 작업기의 실시간 시뮬레이션

차영택(Young Taek Cha),이연호(Yeon Ho Lee),김정구(Jung Gu Kim),최성준(Sung Jun Choi) 대한기계학회 2021 대한기계학회 춘추학술대회 Vol.2021 No.10

웨어러블 조작기로 조정되는 다관절 작업기의 경우, 운전자가 작업기의 제어 루프(Loop) 안에 있는 Human-In-The-Loop 형태의 제어 방식을 취하고 있기 때문에, 작업 대상물과 작업기의 동작에 대한 운전자의 반응은 웨어러블 조작기 및 작업기의 기구 구성과 적용된 제어기의 성능에 따라 달라진다. 이러한 운전자의 조작과 반응을 시스템 설계단계에서부터 반영하기 위해서는, 운전자와 실시간으로 상호작용할 수 있는 시스템 시뮬레이션이 적용되어야 한다. 하지만, 유압 구동계를 가지고 있는 다관절의 경우, 유압 구동계의 시스템 시뮬레이션이 수치적으로 스티프(Stiff)하므로, 실시간 시뮬레이션에 적합한 수치해석기법의 적용과 유압회로의 간략화 및 유압 파라미터의 튜닝이 필요하다. 그러한 측면에서, 본 논문에서는 유압 구동계가 적용된 6축 다관절 작업기에 대한 실시간 시뮬레이션 방안을 제안하였으며, 가상 환경상에서 몇가지 작업을 수행함으로써, 실시간성을 평가하였다. 또한, 각 관절의 단독 동작과 복합 동작에 대해 시험결과와 비교함으로서, 제안된 실시간 시뮬레이션 방안의 타당성을 평가하였다. In the case of a multi-joint manipulator controlled by a wearable joystick, since the driver takes a human-in-the-loop type control method within the multi-joint manipulator’s control loop, the drivers reaction to the work object and the operation of the work machine depends on the mechanical configuration and the applied controllers performance. In order to reflect the drivers manipulation and reaction from the system design stage, a system simulation capable of interacting with the driver in real-time must be applied. However, in the case of a multi-joint having a hydraulic drive system since the system simulation of the hydraulic drive system is numerically stiff, application of numerical analysis suitable for real-time simulation, simplification of hydraulic circuits, and tuning of hydraulic parameters are required. In this respect, this paper proposed a real-time simulation method for a 6-axis multi-joint work machine to which a hydraulic driver is applied, and real-time performance was evaluated by several tasks on a virtual environment. In addition, the validity of the proposed real-time simulation method was evaluated by comparing the test results with the single and complex movements of each joint.

Tip-position/velocity Tracking Control of Manipulator for Hull Derusting and Spray Painting based on Active Disturbance Rejection Control

Zhong Wang,Xiao-Hong Jiao,Meiyu Feng 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.4

During sandblasting and spray painting for hull, the tracking performance of the end-effector of manipulator to the outer surface of the hull in uniform velocity is seriously affected by uncertainty of the electrohydraulic actuator and deflection of the manipulator. To effectively improve the tracking performance of the tipposition/ velocity, a novel tracking control strategy is proposed, which is based on active disturbance rejection control (ADRC) with extended state observer (ESO) and setting position feedforward control with deflection compensation. First, to reduce tracking error caused by the deflection, the reference positions of two cylinders driving telescopic and luffing motion are calculated with consideration of the deflection influence according to manipulator geometry. And then, ADRC technique is adopted to design the position servo controller of the luffing/telescopic cylinder with the help of the estimate for the uncertainty of the electro-hydraulic system by the ESO. The stability of the whole closed-loop system and the convergence of tracking error are guaranteed theoretically, simultaneously, simulation carried out in Matlab/Simulink environment with physical parameters of a real system demonstrates the effectiveness and superiority of the proposed control strategy compared with existing control schemes. Furthermore, the experimental result is given to show the feasibility and availability of the control method.