• 제목/요약/키워드: compliant structure

검색결과 81건 처리시간 0.025초

비대칭 구조를 갖는 두 협조 로봇의 컴플라이언스 제어방법 (A compliant control method for cooperating two arms with asymetric kinematic structures)

  • 여희주;서일홍
    • 전자공학회논문지B
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    • 제33B권7호
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    • pp.40-50
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    • 1996
  • An unified compliant control algorithm to regulate the force by dual arms is proposed, where tow arms are treated as one arm in a kinematic viewpoint. The force error calculated form the information of two force/torque sensors attached to the end of each arm is transferred to minimum actuator coordinates, and then is distributed to total system actuator coordinates. The position adjustment at the total actuator coordinates is computed based on the effective computed based on the effective compliance matrix with respect to total actuator coordinates, which is obtained by coordinate transformation between the task coordinates and the total actuator coordinates. An experiment is carried out for dual arms with asymmetric kinematic structure to control an interaction force between manipulators and the environment. The performances of the proposed control algorithm are experimentally compared to those of dual arms employing master/slave scheme. The proposed compliant control algorithm not only ouperforms other algorithms, but also can be treated as an unified approach n the sense that it can be applied to arbitrary dual arm systems with general kinematic structures.

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Compliant Ultrasound Proximity Sensor for the Safe Operation of Human Friendly Robots Integrated with Tactile Sensing Capability

  • Cho, Il-Joo;Lee, Hyung-Kew;Chang, Sun-Il;Yoon, Euisik
    • Journal of Electrical Engineering and Technology
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    • 제12권1호
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    • pp.310-316
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    • 2017
  • The robot proximity and tactile sensors can be categorized into two groups: grip sensors and safety sensors. They have different performance requirements. The safety sensor should have long proximity range and fast response in order to secure enough response time before colliding with ambient objects. As for the tactile sensing function, the safety sensor need to be fast and compliant to mitigate the impact from a collision. In order to meet these requirements, we proposed and demonstrated a compliant integrated safety sensor suitable to human-friendly robots. An ultrasonic proximity sensor and a piezoelectric tactile sensor made of PVDF films have been integrated in a compliant PDMS structure. The implemented sensor demonstrated the maximum proximity range of 35 cm. The directional tolerance for 30 cm detection range was about ${\pm}15^{\circ}$ from the normal axis. The integrated PVDF tactile sensor was able to detect various impacts of up to 20 N in a controlled experimental setup.

컴플라이언트 메커니즘을 이용한 스윙 암 액추에이터의 설계 - 강성 효과를 고려한 다중목적 최적화 설계 - (Design of a Swing-arm Actuator using the Compliant Mechanism - Multi-objective Optimal Design Considering the Stiffness Effect)

  • 이충용;민승재;유정훈
    • 대한기계학회논문집A
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    • 제30권2호
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    • pp.128-134
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    • 2006
  • Topology optimization is an effective scheme to obtain the initial design concept: however, it is hard to apply in case of non-linear or multi-objective problems. In this study, a modified topology optimization method is proposed to generate a structure of a swing arm type actuator satisfying maximum compliance as well. as maximum stiffness using the multi-objective optimization. approach. The multi-objective function is defined to maximize the compliance in the direction of focusing of the actuator and the second eigen-frequency of the structure. The design of experiments are performed and the response surface functions are formulated to construct the multi-objective function. The weighting factors between conflicting functions are determined by the back-error propagation neural network and the solution of multi-objective function is acquired using the genetic algorithm.

Soil interaction effects on the performance of compliant liquid column damper for seismic vibration control of short period structures

  • Ghosh, Ratan Kumar;Ghosh, Aparna Dey
    • Structural Engineering and Mechanics
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    • 제28권1호
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    • pp.89-105
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    • 2008
  • The paper presents a study on the effects of soil-structure-interaction (SSI) on the performance of the compliant liquid column damper (CLCD) for the seismic vibration control of short period structures. The frequency-domain formulation for the input-output relation of a flexible-base structure with CLCD has been derived. The superstructure has been modeled as a linear, single degreeof-freedom (SDOF) system. The foundation has been considered to be attached to the underlying soil medium through linear springs and viscous dashpots, the properties of which have been represented by complex valued impedance functions. By using a standard equivalent linearization technique, the nonlinear orifice damping of the CLCD has been replaced by equivalent linear viscous damping. A numerical stochastic study has been carried out to study the functioning of the CLCD for varying degrees of SSI. Comparison of the damper performance when it is tuned to the fixed-base structural frequency and when tuned to the flexible-base structural frequency has been made. The effects of SSI on the optimal value of the orifice damping coefficient of the damper has also been studied. A more convenient approach for designing the damper while considering SSI, by using an established model of a replacement oscillator for the structure-soil system has also been presented. Finally, a simulation study, using a recorded accelerogram, has been carried out on the CLCD performance for the flexible-base structure.

금속오링씰의 컴플라이언트 메커니즘 위상최적설계 (Compliant Mechanism Topology Optimization of Metal O-Ring)

  • 김근홍;이영신;양형렬
    • 대한기계학회논문집A
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    • 제37권4호
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    • pp.537-545
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    • 2013
  • 금속씰의 탄성복원력은 기밀성능을 결정하는 매우 중요한 요소이다. 본 연구는 장시간 운전조건에서 기밀성능을 유지할 수 있는 금속오링씰의 구조, 즉 탄성복원력이 우수한 구조를 얻기 위하여 컴플라이언트 메커니즘 위상최적화법을 도입하였다. 진화구조최적화법의 위상최적화 알고리듬이 사용되었으며, 강성 및 유연성을 동시에 고려하는 두 가지 종류의 목적함수가 사용되었다. 금속오링씰의 외형을 고려하여 원형의 최적화 설계영역이 고려되었으며 최적화 결과로 나타난 위상의 탄성복원력은 상용품의 탄성복원력과 비교되었다.

Design and Development of a Functional Safety Compliant Electric Power Steering System

  • Lee, Kyung-Jung;Lee, Ki-Ho;Moon, Chanwoo;Chang, Hyuk-Jun;Ahn, Hyun-Sik
    • Journal of Electrical Engineering and Technology
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    • 제10권4호
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    • pp.1915-1920
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    • 2015
  • ISO 26262 is an international standard for the functional safety of electric and electronic systems in vehicles, and this standard has become a major issue in the automotive industry. In this paper, a functional safety compliant electronic control unit (ECU) for an electric power steering (EPS) system and a demonstration purposed EPS system are developed, and a software and hardware structure for a safety critical system is presented. EPS is the most recently introduced power steering technology for vehicles, and it can improve driver’s convenience and fuel efficiency. In conformity with the design process specified in ISO 26262, the Automotive Safety Integrity Level (ASIL) of an EPS system is evaluated, and hardware and software are designed based on an asymmetric dual processing unit architecture and an external watchdog. The developed EPS system effectively demonstrates the fault detection and diagnostic functions of a functional safety compliant ECU as well as the basic EPS functions.

Compliant Micro Actuator made from Dielectric Polymer

  • Sunghwi Cho;Sungmoo Ryew;Jeon, Jae-Wook;Kim, Hunmo;Nam, Jae-Do;Park, Hyoukryeol;Ryutaro Maeda
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.103.2-103
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    • 2001
  • In this paper, we discusses compliant actuators those are made of electrostrictive polymer. Electrostrictive polymer actuators(EPAs) are based on the deformation of dielectric elastomer polymer in the presence of an electric field. We address actual design and fabrication method of an actuator using the electrostrictive polymer. We have developed primitive prototypes of the actuator using elastic restoring force. And they actuators have 1 to 3 DOF, 1 DOF actuators are simple linear actuators and 3 DOF actuator has linear actuation and steering capability. They are simple in structure with lightweight, high trust, force and large stroke. Basic design principles and experimental procedures for confirming their performance will be introduced.

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혈관 유연성을 고려한 경동맥 분기부 모델 혈류역학 해석 (Numerical Study on Blood Flow Dynamics and Wall Mechanics in a Compliant Carotid Bifurcation Model)

  • 웬민투안;이상욱
    • 한국가시화정보학회지
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    • 제13권2호
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    • pp.28-32
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    • 2015
  • Blood flow simulations in an realistic carotid bifurcation model with considering wall compliance were carried out to investigate the effect of wall elasticity on the wall shear stress and wall solid stress. Canonical waveforms of flow rates and pressure in carotid arteries were imposed for boundary conditions. Compared to a rigid wall model, we found an increased recirculation region at the carotid bulb and an overall reduction of wall shear stress in a compliant model. Additionally, there was appreciable change of flow rate and pressure wave in longitudinal direction. Both solid and wall shear stress concentration occur at the bifurcation apex.

순응형 파지와 정밀한 집기가 가능한 유연한 그리퍼의 강도 및 강성 분석 (Strength and Stiffness Analysis for a Flexible Gripper with Parallel Pinching and Compliant Grasping Capabilities)

  • 이덕원;전형석;정용준;김용재
    • 제어로봇시스템학회논문지
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    • 제22권10호
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    • pp.817-825
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    • 2016
  • In this paper, we introduce a flexible gripper that we have engineered to precisely pinch in parallel and compliantly grasp objects. As found in most conventional industrial grippers, the parallel pinching property is essential for precise manipulation. On the other hand, the grippers with a flexible structure are more adept at grasping objects with arbitrary shapes and softness. To achieve these disparate properties, we introduce a flexible gripper mechanism composed of multiple flexible beam structures. Utilizing these beam structures, the proposed gripper is able to grasp arbitrarily shaped objects. Additionally, a unique combination of flexible beams enables the gripper to pinch objects using the parallel fingertips for enhanced precision. A detailed description of the proposed mechanism is provided, and an analysis of the strength and stiffness of the fingertip and finger body is presented. The Results section compares the theoretical and experimental analyses and verifies the properties and performance of the proposed gripper.