• Title/Summary/Keyword: 힘 제어

Search Result 552, Processing Time 0.025 seconds

Force Control of one pair of 6-Link Electro-Hydraulic Manipulators (한 쌍의 6축 전기유압 매니퓰레이터의 힘제어)

  • 안경관;조용래;양순용;이병룡
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1997.10a
    • /
    • pp.353-356
    • /
    • 1997
  • Hydraulically driven manipulators are superior to electrically driven ones in the power density and electrical insulation. But an electro-hydraulic manipulator using hydraulic actuators has many nonlinear elements, and this parameter fluctuations are greater than those of electrically driven manipulator. So this is relatively difficult to realize not only stable contact work but also accurate force control for the autonomous field task such as the maintenance task of high voltage active electric line or the automatic excavation task by hydraulic excavator. In this report, we propose robust force control algorithm, which can be applied to there real field task such as the construction field, nuclear plant and so on. Proposed force controller has the same structure as that of disturbance observe for position control. The difference between force and position disturbance observer is that the input and output of disturbance observer are forces in the case force disturbance observer and the plant varies much compared to the case of position control. In the design of force disturbance observer, generalized plant is derived and the stabilized filter is designed by H infinity control theory to ensure the robuts t stability even though the stiffness of environment changes from sponge to steel, and the contact surface also changes from flat to round shape. Experimental results show that highly robust force tracking by a 6-link electro-hydraulic manipulator could be achieved under various environment conditions.

  • PDF

Slip Detection of Robot Gripper with Flexible Tactile Sensor (유연 촉각 센서를 이용한 로봇 그리퍼의 미끄러짐 감지)

  • Seo, Ji Won;Lee, Ju Kyoung;Lee, Suk;Lee, Kyung Chang
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.31 no.2
    • /
    • pp.157-164
    • /
    • 2014
  • In this paper, we design a gripping force control system using tactile sensor to prevent slip when gripper tries to grasp and lift an object. We use a flexible tactile sensor for measuring uniplanar pressure on gripper's finger and develop an algorithm to detect the onset of slip using the sensor output. We also use a flexible pressure sensor to measure the normal force. In addition, various signal processing techniques are used to reduce noise included in the sensor output. A 3-finger gripper is used to grasp and lift up a cylindrical object. The tactile sensor is attached on one of fingers, and sends output signals to detect slip. Whenever the sensor signal is similar to the slip pattern, gripper force is increased. In conclusion, this research shows that slip can be detected using the tactile sensor and we can control gripping force to eliminate slip between gripper and object.

Development of a New 6-DOF Parallel-type Motion Simulator (6자유도 병렬형 모션 시뮬레이터 개발)

  • Kim, Han-Sung
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.19 no.2
    • /
    • pp.171-177
    • /
    • 2010
  • This paper presents the development of a new 6-DOF parallel-kinematic motion simulator. The moving platform is connected to the fixed base by six P-S-U (Prismatic-Spherical-Universal) serial chains. Comparing with the well-known Gough-Stewart platform-type motion simulator, it uses commercialized linear actuators mounted at the fixed base whereas a 6-UPS manipulator uses telescopic linear ones. Therefore, the proposed motion simulator has the advantages of easier fabrication and lower inertia over a 6-UPS counterpart. Furthermore, since most forces acting along the legs are transmitted to the structure of linear actuators, smaller actuation forces are required. The inverse position and Jacobian matrix are analyzed. In order to further increase workspace, inclined arrangement of universal joints is introduced. The optimal design considering workspace and force transmission capability has been performed. The prototype motion simulator and PC-based real-time controller have been developed. Finally, position control experiment on the prototype has been performed.

Real-Time Force Control of Biped Robot to Generate High-Speed Horizontal Motion of Center of Mass (이족 로봇의 무게 중심 수평 위치 고속 이동을 위한 실시간 힘 제어 기법)

  • Lee, Yisoo;Park, Jaeheung
    • The Journal of Korea Robotics Society
    • /
    • v.11 no.3
    • /
    • pp.183-192
    • /
    • 2016
  • Generating motion of center of mass for biped robots is a challenging issue since biped robots can easily lose balance due to limited contact area between foot and ground. In this paper, we propose force control method to generate high-speed motion of the center of mass for horizontal direction without losing balancing condition. Contact consistent multi-body dynamics of the robot is used to calculate force for horizontal direction of the center of mass considering balance. The calculated force is applied for acceleration or deceleration of the center of mass to generate high speed motion. The linear inverted pendulum model is used to estimate motion of the center of mass and the estimated motion is used to select either maximum or minimum force to stop at goal position. The proposed method is verified by experiments using 12-DOF torque controlled human sized legged robot.

Force and Position Control of a Two-Link Flexible Manipulator with Piezoelectric Actuators (압전 작동기를 갖는 2 링크 유연 매니퓰레이터의 힘 및 위치 제어)

  • 김형규;최승복
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 1997.04a
    • /
    • pp.428-433
    • /
    • 1997
  • This paper presents a new control strategy for the position and force control of flexible manipulators. The governing equation of motion of a two-link flexible manipulator which features piezoceramic actuators bonded on each flexible beam is derived via Hamilton's principle. The control torque of the motor to command desired position and force is determined by a sliding mode controller on the basis of the rigid-mode dynamics. In the controller formulation, the sliding mode controller with perturbation estimation(SMCPE) is adopted to determine appropriate control gains. The SMCPE is then incorporated with the fuzzy technique to mitigate inherent chattering problem while maintaining the stability of the system. A set of fuzzy parameters and control rules are obtained from a relation between estimated perturbation and actual perturbation. During the commanded motion, undesirable oscillation is actively suppressed by applying feedback control voltages to the piezoceramic actuators. These feedback voltages are also determined by the SMCPE. Consequently, accurate force and position control of a two-link flexible manipulator are achieved. Computer simulations are undertaken in order to demonstrate the effectiveness of the proposed control methodology.

  • PDF

Force and Pose control for Anthropomorphic Robotic Hand with Redundancy (여유자유도를 가지는 인간형 로봇 손의 자세 및 힘 제어)

  • Yee, Gun Kyu;Kim, Yong Bum;Kim, Anna;Kang, Gitae;Choi, Hyouk Ryeol
    • The Journal of Korea Robotics Society
    • /
    • v.10 no.4
    • /
    • pp.179-185
    • /
    • 2015
  • The versatility of a human hand is what the researchers eager to mimic. As one of the attempt, the redundant degree of freedom in the human hand is considered. However, in the force domain the redundant joint causes a control issue. To solve this problem, the force control method for a redundant robotic hand which is similar to the human is proposed. First, the redundancy of the human hand is analyzed. Then, to resolve the redundancy in force domain, the artificial minimum energy point is specified and the restoring force is used to control the configuration of the finger other than the force in a null space. Finally, the method is verified experimentally with a commercial robot hand, called Allegro Hand with a force/torque sensor.

A posture correction of the biped robot using the accelerometer (가속도 센서를 이용한 이족 로봇의 자세보정)

  • Lee, Sung-Ui;Seo, Jae-Kwan;Oh, Sung-Nam;Kim, Kab-Il
    • Proceedings of the KIEE Conference
    • /
    • 2002.07d
    • /
    • pp.2546-2549
    • /
    • 2002
  • 이족 로봇(A biped robot)의 안정된 보행과 움직임을 구현하기 위해서는 정밀 센서의 접목이 필수 사항이다. 센서의 정보를 종합한 다음 보행 및 움직임에 적용함으로써 로봇은 향상된 독립성과 자율성을 가지게 되고 그로 인해 지능형 로봇에 한층 더 접근할 수 있게된다. 본 논문에서는 이족로봇의 안정된 보행을 위해 기본이 되는 자세 기울어짐을 측정할 수 있는 가속도 센서를 이용한 이족로봇의 제어 방법을 다루고자 한다. 본 논문의 로봇은 소형 R/C servo motor를 사용하여 설계, 제작 하였으며, 하드웨어 시스템은 메인 CPU로 인텔사의 80C296SA50을 사용, 가속도 측정센서로는 Analog Device 사의 Accelerometer ADXL210를 사용하였다. 이와 같이 가속도 센서를 사용한 시스템은 로봇의 자세를 측정, 판단을 가능케 하여 실시간으로 로봇의 자세를 안정되게 보정 할 수 있어 외부의 변화되는 힘에 자율적으로 대처할 수 있다. 이 때문에 더욱 안정된 지능형 이족로봇을 구현할 수 있다.

  • PDF

Optimal Force Distribution for Compliance Control of Multi-legged Walking Robots (다각 보행로보트의 순응 제어를 위한 힘의 최적 분배)

  • Ra, In-Hwan;Yang, Won-Young;Chung, Tae-Sang
    • Proceedings of the KIEE Conference
    • /
    • 1995.07b
    • /
    • pp.874-876
    • /
    • 1995
  • Force and compliance control has been used in the control of legged walking vehicles to achieve superior terrain adaptability on rough terrains. The compliance control requires distribution of the vehicle load over the supporting legs. However, the constraint equations for ground reaction forces of supporting legs are generally underdetermined, allowing an infinite number of solutions. Thus, it is possible to apply an optimization criteria in solving the force setpoint problem. It has been observed that the previous force setpoint optimization methods sometimes cause a system stability problem and/or the load distribution among supporting legs is not well balanced due to a memory effect on the solution trajectory, This paper presents an iterative force setpoint method to solve this problem using an interpolation technique. By simulation it was shown that an excessive load unbalance among supporting legs and the memory effect in the force trajectory are alleviated much with the proposed method.

  • PDF

Design of a Hybrid Controller to Eliminate the Force Ripple in the Linear Motor (선형 모터에서 힘리플 제거를 위한 Hybrid 제어기의 설계)

  • Kim, Kyong-Chon;Kim, Jung-Jae;Choi, Young-Man;Gweon, Dae-Gab
    • Journal of the Semiconductor & Display Technology
    • /
    • v.7 no.1
    • /
    • pp.17-22
    • /
    • 2008
  • The proposed hybrid controller consists of PID controller, feedforward controller and RLSE (Recursive Least Square Estimating) adaptive controller to compensate the force ripple that is periodic function of position in a linear motor. The modeling of force ripple is divided into the current-dependent and current-independent components. The current independent components never change as the current into the linear motor changes. On the other hand, the current-dependent components change as current varies when the velocity and load of the linear motor change. The proposed controller can compensate both force ripples. The feedforward controller compensates the current-independent components and the RLSE adaptive controller compensates the current-dependents components. We verified the performance of the controller by simulation and experiments.

  • PDF

Robot Mobile Control Technology Using Robot Arm as Haptic Interface (로봇의 팔을 햅틱 인터페이스로 사용하여 로봇의 이동을 제어하는 기술)

  • Jung, Yu Chul;Lee, Seongsoo
    • Journal of IKEEE
    • /
    • v.17 no.1
    • /
    • pp.44-50
    • /
    • 2013
  • This paper proposed the implementation of haptic-based robot which is following a human by using fundamental sensors on robot arms without additional sensors. Joints in the robot arms have several motors, and their angles can be read out by these motors when a human pushes or pulls the robot arms. So these arms can be used as haptic sensors. The implemented robot follows a human by interacting with robot arms and human hands, as a human follows a human by hands.