Force feedback control of robot manipulator by the acceleration tracing orientation method

Teleoperation systems are subject to different types of disturbances. Such disturbances, when unaccounted for, may cause poor performance and even instability of the teleoperation system. This paper presents a novel nonlinear bilateral control scheme using the concept of disturbance observer based control for nonlinear teleoperation systems. Lumping the effects of dynamic uncertainties and external disturbances into a single disturbance term enables us to design a disturbance observer in order to suppress these disturbances and alleviate their adverse effects on the teleoperation system. A disturbance observer based control law is proposed for nonlinear teleoperation systems which will guarantee global asymptotic force tracking and global exponential position and disturbance tracking when the bilateral teleoperation system is experiencing slow-varying disturbances. In the case of fastvarying disturbances, the tracking errors are shown to be globally uniformly ultimately bounded, with an ultimate bound that can be made as small as desired using the design parameters. Simulations are presented to show the effectiveness of the proposed approach.

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“…. , and C 6 are chosen as in (19), (20) and (21). The controllers and disturbance observer gains and initial conditions are chosen as…”

Section: Simulation Studymentioning

confidence: 99%

“…Similar schemes have been used in applications such as control of direct drive motors, mechatronics system control [15], [16], [17], independent robot joint control [18], robot joint friction compensation [19], [20], and sensorless torque control of robotic manipulators [21], [22].…”

Section: Introductionmentioning

confidence: 99%

Disturbance observer-based control of non-linear haptic teleoperation systems

Mohammadi

Tavakoli

Marquez

2011

IET Control Theory Appl.

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“…In addition, the break point frequency of the Q-filter can also affect the performance of the system (8) . When the break point frequency of the filter is within the control bandwidth, the nominalization of the system cannot be achieved (10,11) . As a result, the frequency characteristics of the closed-control system (i.e., pneumatic isolation table) in the frequency region within the control bandwidth can be changed which creates the need for redesign of the feedback controller.…”

Section: Introductionmentioning

confidence: 99%

“…In order to circumvent the use of a sensor for the measurement of a disturbance, disturbance observers (DOBs) (7) are widely used for the rejection of disturbances to the systems in various applications (8)(9)(10)(11) . For the implementation of DOBs, low pass filters which are known as Q-filter are used together with inverse nominal plant.…”

Section: Introductionmentioning

confidence: 99%

Flow Disturbance Compensation Based on Off-Line Estimated Signal for a Pneumatic Isolation Table

Shirani

Nakamura

Wakui

2013

JAMDSM

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The flow disturbance to a pneumatic vibration isolation table causes periodic fluctuation of the table. In current study, one cycle of flow disturbance is estimated offline using a disturbance observer. The time series data of one cycle estimated disturbance is then stored in the memory of digital signal processor. The program codes are prepared which can detect every cycle of the flow disturbance based on the threshold of table position. The estimated signal is then repeatedly injected from the memory through a compensator to the servo valve to suppress table fluctuation due to periodic actual flow disturbance. The effectiveness of this method is demonstrated by experimental results.

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“…Many friction models and compensation methods have been proposed [3]. One of the most promising methods is observer-based control where a DO is used to estimate friction [4]; 3) DO's have been used in robotic manipulators for force feedback and hybrid position/force control where the DO works as a torque sensor [5]- [7]. In this case, it is supposed that the friction and other dynamics are well modeled and compensated for.…”

mentioning

confidence: 99%