• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 D
• /
• pp.2674-2676
• /
• 2004

In this paper, web based monitoring systems are implemented for multi-axis force control systems of an intelligence robot. A web based monitoring system is implemented by porting Linux at embeded systems which include Xscale processors. A divice driver is developed to receive data from multy-axis force sensors in Linux operation systems. To control this device driver, a soket program for web browser is also developped.

• 문화기술의 융합
• /
• 제8권5호
• /
• pp.547-552
• /
• 2022

본 연구에서는 궤도틀림이 차륜-레일 상호작용력에 미치는 영향을 분석하고 이를 바탕으로 궤도틀림을 관리할 수 있는 하중기반의 궤도틀림 분석기법을 제안하였다. 도시철도 침목플로팅궤도와 직결도상 접속구간에서 발생된 고저틀림 측정결과를 이용하여 고저틀림이 차륜-레일 상호작용력(동적윤중)과 레일의 진동가속도에 미치는 영향을 해석적으로 분석하였다. 직결궤도 총 4개소를 대상으로 부분적으로 직결궤도를 포함한 침목플로팅궤도 구간과 전, 후 인접 침목플로팅궤도 구간으로 구분하여 고저틀림을 비교, 분석하였다. 분석결과, 직결궤도를 포함한 구간이 침목플로팅궤도 보다 궤도틀림이 크게 나타났다. 고저틀림 데이터를 적용한 차륜-레일 상호작용력 분석결과, 거리에 비해 상대 변위차가 큰 구간에서 차륜-레일 상호작용력과 레일가속도가 증가하는 것으로 분석되었다. 반면 고저틀림 데이터의주기와 틀림량(변위)이 일정한 구간의 경우 차륜-레일 상호작용력과 레일가속도가 상대적으로 작게 나타났다. 따라서고저틀림의 주기가 짧고 상대변위차가 클수록 차륜-레일 상호작용력 측면에서 불리한 것으로 분석되었다. 본 연구에서는 궤도틀림 측정데이터를 이용한 차륜-레일 상호작용 해석을 통해 차륜-레일의 상호작용력을 바탕으로한 하중기반의 궤도틀림 분석기법 적용방안을 제시하였다.

• Structural Monitoring and Maintenance
• /
• 제5권1호
• /
• pp.93-110
• /
• 2018

In order to provide a novel strategy for long-span bridge health monitoring system design, this paper proposes a novel ultimate bearing capacity ratios based bridge internal force monitoring design method. The bridge ultimate bearing capacity analysis theories are briefly described. Then, based on the ultimate bearing capacity of the structural component, the component ultimate bearing capacity ratio, the uniformity of ultimate bearing capacity ratio, and the reference of component ultimate bearing capacity ratio are defined. Based on the defined indices, the high bearing components can then be found, and the internal force monitoring system can be designed. Finally, the proposed method is applied to the bridge health monitoring system design of the second highway bridge of Wuhu Yangtze river. Through the ultimate bearing capacity analysis of the bridge in eight load conditions, the high bearing components are found based on the proposed method. The bridge internal force monitoring system is then preliminary designed. The results show that the proposed method can provide quantitative criteria for sensors layout. The monitoring components based on the proposed method are consistent with the actual failure process of the bridge, and can reduce the monitoring of low bearing components. For the second highway bridge of Wuhu Yangtze river, only 59 components are designed to be monitored their internal forces. Therefore, the bridge internal force monitoring system based on the ultimate bearing capacity ratio can decrease the number of monitored components and the cost of the whole monitoring system.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
• /
• pp.253-256
• /
• 1997

This paper proposes a control strategy of position and force control in the same direction based on hybrid position/force control. In order to control position and force in the same direction, a weighting matrix is introduced instead of a selection matrix suggested by Raibert and Craig. The major part of the controller output comes from the position controller when a position control error is large, from the force controller when a position control error is large. The proposed algorithm is implemented by the simulation and experiment focusing on the peg-in-hole task where friction exist significantly and is not constant. It also adopts and event control scheme for more efficient performance.

• 센서학회지
• /
• 제23권6호
• /
• pp.357-361
• /
• 2014

This paper describes the evaluation of the effectiveness of rehabilitation therapy for patients with finger paralysis based on a two-finger force measurement system (TFFMS). The paralyzed fingers can be recovered through rehabilitation therapies. The finger pressing force of the patients can be measured utilizing the TFFMS previously developed by the author [7]. The TFFMS, however, has not been fully adopted as a standard method for evaluating the therapy owing to the lack of a standard protocol. The pressing force of healthy volunteers and patients is analyzed with the TFFMS to explore the feasibility of the TFFMS as an evaluation device. The test confirms that the established standard protocol is useful to quantitatively assess the progress of finger rehabilitation therapy.

• 한국생산제조학회지
• /
• 제8권1호
• /
• pp.100-111
• /
• 1999

This paper resents a discrete-time model of an edge-following with accommodation force control. Since an irregular workpiece shape causes disturbances to the system while following an edge, the use of preview control is proposed to improve the system performance. The preview control employs future information of the workpiece contour shape, and it can be developed by LQ-optimal control principles. This study provides a general method how to utilize the local future information obtained by the finite preview to minimize an optimality criterion evaluated over a problem duration. The force controller is designed based on the preview control scheme, and then implemented on a VME-based computer. Experimental results using an industrial robot show that the preview control system achieves faster tracking speed and better force regulation than the conventional nonpreview control system.

• 한국산업융합학회 논문집
• /
• 제3권2호
• /
• pp.123-130
• /
• 2000

Fuzzy control is proposed to regulate cutting force in turning operations under varying cutting conditions. The traditional linear controllers based on crisp mathematical model cannot effectively control cutting force becasue of the nonlinear dynamics of turning operations. The proposed fuzzy controller is based on operator experience and expert knowledge. The membership functions for the inputs and the output of the controller are designed. Cutting force is regulated by adjusting feedrate according to the variation of cutting conditions. The performance of the proposed controller is evaluated by experiments. The results of experiments show that the proposed fuzzy controller has a good cutting force regulation over a wide range of cutting conditions.

• International Journal of Control, Automation, and Systems
• /
• 제2권2호
• /
• pp.238-246
• /
• 2004

In displaying a virtual wall using a passive haptic device equipped with passive actuators such as electric brakes, unsmooth motion frequently occurs. This undesirable behavior is attributed to time delay due to slowness in the virtual environment update and force approximation due to the inability of a brake to generate torque in arbitrary directions. In this paper a new control scheme called direct control is proposed to achieve smooth display on the wall-following task with a passive haptic device. In direct control, brakes are controlled so that the normal component of a resultant force at the end-effector vanishes, based on the force analysis at the end-effector of the passive haptic device using the passive FME (Force Manipulability Ellipsoid). Various experiments have been conducted to verify the validity of the direct control scheme with a 2-link passive haptic system.

• Journal of Mechanical Science and Technology
• /
• 제18권5호
• /
• pp.789-797
• /
• 2004

The nanoscale sensing and manipulation have become a challenging issue in micro/nano-robotic applications. In particular, a feedback sensor-based manipulation is necessary for realizing an efficient and reliable handling of particles under uncertain environment in a micro/nano scale. This paper presents a piezoresistive MEMS cantilever for nanoscale force measurement in micro robotics. A piezoresistive MEMS cantilever enables sensing of gripping and contact forces in nanonewton resolution by measuring changes in the stress-induced electrical resistances. The calibration of a piezoresistive MEMS cantilever is experimentally carried out. In addition, as part of the work on nanomanipulation with a piezoresistive MEMS cantilever, the analysis on the interaction forces between a tip and a material, and the associated manipulation strategies are investigated. Experiments and simulations show that a piezoresistive MEMS cantilever integrated into a micro robotic system can be effectively used in nanoscale force measurements and a sensor-based manipulation.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.50-52
• /
• 2004

Mobility of an indoor wheeled robot is affected by adhesion force that is related to various floor conditions. When the adhesion force between driving wheels and the floor decreases suddenly, the robot has slip state. First of all, this paper models adhesion characteristics and slip in wheeled robot. Secondly, the paper proposes estimation method of adhesion force coefficient according to slip velocity. In oder to overcome this slip problem, optimal slip velocity must be decided for stable movement of wheeled robot. The paper proposes an anti-slip control system based on an ordinary disturbance observer, that is, the anti-slip control is achieved by reducing the driving torque enough to give maximum adhesion force coefficient. These procedure is implemented using a Pioneer 2-DXE parameter.