18 research outputs found

    Position referenced force augmentation in teleoperated hydraulic manipulators operating under delayed and lossy networks: a pilot study.

    Get PDF
    Position error between motions of the master and slave end-effectors is inevitable as it originates from hard-to-avoid imperfections in controller design and model uncertainty. Moreover, when a slave manipulator is controlled through a delayed and lossy communication channel, the error between the desired motion originating from the master device and the actual movement of the slave manipulator end-effector is further exacerbated. This paper introduces a force feedback scheme to alleviate this problem by simply guiding the operator to slow down the haptic device motion and, in turn, allows the slave manipulator to follow the desired trajectory closely. Using this scheme, the master haptic device generates a force, which is proportional to the position error at the slave end-effector, and opposite to the operator's intended motion at the master site. Indeed, this force is a signal or cue to the operator for reducing the hand speed when position error, due to delayed and lossy network, appears at the slave site. Effectiveness of the proposed scheme is validated by performing experiments on a hydraulic telemanipulator setup developed for performing live-line maintenance. Experiments are conducted when the system operates under both dedicated and wireless networks. Results show that the scheme performs well in reducing the position error between the haptic device and the slave end-effector. Specifically, by utilizing the proposed force, the mean position error, for the case presented here, reduces by at least 92% as compared to the condition without the proposed force augmentation scheme. The scheme is easy to implement, as the only required on-line measurement is the angular displacement of the slave manipulator joints

    A prototype telerobotic platform for live transmission line maintenance: review of design and development.

    Get PDF
    This paper reports technical design of a novel experimental test facility, using haptic-enabled teleoperation of robotic manipulators, for live transmission line maintenance. The goal is to study and develop appropriate techniques in repair overhead power transmission lines by allowing linemen to wirelessly guide a remote manipulator, installed on a crane bucket, to execute dexterous maintenance tasks, such as twisting a tie wire around a cable. Challenges and solutions for developing such a system are outlined. The test facility consists of a PHANToM Desktop haptic device (master site), an industrial hydraulic manipulator (slave site) mounted atop a Stewart platform, and a wireless communication channel connecting the master and slave sites. The teleoperated system is tested under different force feedback schemes, while the base is excited and the communication channel is delayed and/or lossy to emulate realistic network behaviors. The force feedback schemes are: virtual fixture, augmentation force and augmented virtual fixture. Performance of each scheme is evaluated under three measures: task completion time, number of failed trials and displacement of the slave manipulator end-effector. The developed test rig has been shown to be successful in performing haptic-enabled teleoperation for live-line maintenance in a laboratory setting. The authors aim at establishing a benchmark test facility for objective evaluation of ideas and concepts in the teleoperation of live-line maintenance tasks

    Selection of network parameters in wireless control of bilateral teleoperated manipulators.

    Get PDF
    This paper describes how to establish performance charts for selection of network parameters for effective utilization of a bilateral teleoperated manipulator working under a wireless communication channel. The goal is to construct a set of charts that help researchers and engineers to select appropriate parameters of wireless network setup for a known configuration of environment obstruction. To achieve this goal, a teleoperated setup comprising a master haptic device, a slave manipulator dynamic simulator, and a communication channel emulated using the network simulator version 2 (NS2) simulator is first developed. Next, performance indices are defined to evaluate the quality of position tracking of the slave manipulator end-effector and force tracking of the master haptic. Three indices chosen in this paper are the integral of squared position and force errors, the integral of absolute position and force error, and the amplitude of position and force overshoot. Extensive experiments on the developed setup are then conducted to study effects of time-varying packet loss on the performance of the teleoperated system. The largest mean packet loss, at which the system exhibits satisfactory tracking, is then quantified. This packet loss is used as an indicator to define regions representing the quality of tracking. The effectiveness of the proposed technique is validated by testing a fully instrumented hydraulically actuated system under various real wireless channel scenarios

    Clinical Study Treatment of Glioma Using neuroArm Surgical System

    Get PDF
    The use of robotic technology in the surgical treatment of brain tumour promises increased precision and accuracy in the performance of surgery. Robotic manipulators may allow superior access to narrow surgical corridors compared to freehand or conventional neurosurgery. This paper reports values and ranges of tool-tissue interaction forces during the performance of glioma surgery using an MR compatible, image-guided neurosurgical robot called neuroArm. The system, capable of microsurgery and stereotaxy, was used in the surgical resection of glioma in seven cases. neuroArm is equipped with force sensors at the end-effector allowing quantification of tool-tissue interaction forces and transmits force of dissection to the surgeon sited at a remote workstation that includes a haptic interface. Interaction forces between the tool tips and the brain tissue were measured for each procedure, and the peak forces were quantified. Results showed maximum and minimum peak force values of 2.89 N (anaplastic astrocytoma, WHO grade III) and 0.50 N (anaplastic oligodendroglioma, WHO grade III), respectively, with the mean of peak forces varying from case to case, depending on type of the glioma. Mean values of the peak forces varied in range of 1.27 N (anaplastic astrocytoma, WHO grade III) to 1.89 N (glioblastoma with oligodendroglial component, WHO grade IV). In some cases, ANOVA test failed to reject the null hypothesis of equality in means of the peak forces measured. However, we could not find a relationship between forces exerted to the pathological tissue and its size, type, or location

    Calibration of Mobile Robotic Systems: A Pilot Study

    No full text
    The type of wheeled mobile robots (WMRs) may affect the level of positional errors during motion. The errors are inevitable, as caused by imperfections in design to fabrication, and need to be rectified using calibration techniques. This paper uses the odometry method to provide improved short-term accuracy with high sampling rates. Odometry is economical and requires fewer landmarks and simpler sensory system to localize WMRs, compared to other existing techniques such as 3D camera error detection. The context introduces an odometry-based method to correct the motion of a WMR with two-wheeled mechanism. Experimental results showed that positional errors were significantly improved after applying outcome of the calibration

    An Analysis of Power Consumption of Fluid-Driven Robotic Arms Using Isotropy Index: A Proof-of-Concept Simulation-Based Study

    No full text
    The manipulability of a robotic arm may be defined based on ease of motion in different directions or ease of applying force/torque. In this study, we use manipulability measures to investigate how the kinematics of robots can be employed to calculate the optimal power required to drive the actuation systems of their arms. We hypothesize that the isotropy measure is related to the power consumption of the robotic arm. In addition to theoretical aspects, we consider practical applications that can minimize power consumption in robotic systems. Since the method is simple to implement and has no assumption on the robot’s work environment or dependence on information on the main power supply, manipulability measures can be used as a tool to predict the power consumption of robotic manipulators

    An Analysis of Power Consumption of Fluid-Driven Robotic Arms Using Isotropy Index: A Proof-of-Concept Simulation-Based Study

    No full text
    The manipulability of a robotic arm may be defined based on ease of motion in different directions or ease of applying force/torque. In this study, we use manipulability measures to investigate how the kinematics of robots can be employed to calculate the optimal power required to drive the actuation systems of their arms. We hypothesize that the isotropy measure is related to the power consumption of the robotic arm. In addition to theoretical aspects, we consider practical applications that can minimize power consumption in robotic systems. Since the method is simple to implement and has no assumption on the robot’s work environment or dependence on information on the main power supply, manipulability measures can be used as a tool to predict the power consumption of robotic manipulators

    A Brief Review on Challenges in Design and Development of Nanorobots for Medical Applications

    No full text
    Robotics is a rapidly growing field, and the innovative idea to scale down the size of robots to the nanometer level has paved a new way of treating human health. Nanorobots have become the focus of many researchers aiming to explore their many potential applications in medicine. This paper focuses on manufacturing techniques involved in the fabrication of nanorobots and their associated challenges in terms of design architecture, sensors, actuators, powering, navigation, data transmission, followed by challenges in applications. In addition, an overview of various nanorobotic systems addresses different architectures of a nanorobot. Moreover, multiple medical applications, such as oncology, drug delivery, and surgery, are reviewed and summarized

    A Historical Review of Medical Robotic Platforms

    No full text
    This paper provides a brief history of medical robotic systems. Since the first use of robots in medical procedures, there have been countless companies competing to developed robotic systems in hopes to dominate a field. Many companies have succeeded, and many have failed. This review paper shows the timeline history of some of the old and most successful medical robots and new robotic systems. As the patents of the most successful system, i.e., Da Vinci® Surgical System, have expired or are expiring soon, this paper can provide some insights for new designers and manufacturers to explore new opportunities in this field
    corecore