Top PDF Error Recovery in Robot Systems

Error Recovery in Robot Systems

Error Recovery in Robot Systems

making the above argument may A characterization of the current state of the world on the basis of a detailed engages sided as For error of servoing can be corrected by simple By ignorin[r]

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Error Recovery Microstrategies in a Touchscreen Environment.

Error Recovery Microstrategies in a Touchscreen Environment.

Newell’s Soar cognitive architecture was one of the first computational systems to be pre- sented as a unified theory of cognition [ New90 ] . Unlike the other architectures discussed in this section, it does not differentiate the perceptual, motor, and cognitive systems. Instead, it represents the world as a problem space in which each possible operator will change declarative memory (how state information is stored). During the decision cycle, all produc- tions that match the current state of declarative memory will fire. Once the first round of productions have been resolved, the state has likely been changed, and more productions may match and fire in the next round. This will continue until no productions match the current state. At this point, a decision procedure fires, and the process repeats. Preference heuristics determine what the next action will be, but if there is any ambiguity as to which action should be taken, the architecture will randomly choose between the possible actions. A new production is created to handle this case, and thus Soar can “learn”.
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Investigation on the Effect of Different Parameters in Wheeled Mobile Robot Error (TECHNICAL NOTE)

Investigation on the Effect of Different Parameters in Wheeled Mobile Robot Error (TECHNICAL NOTE)

4.5. Effect of Control System on Mobile Robot Errors A good control system can improve mobile robot error which depends on various and complicated parameters such as unsynchronized rotation of the wheels, geometrical considerations of wheels and encoder's defects (sliding, misalignment, etc). Previous instances are common problems in mobile robots. These problems are usually manufacturing defects and depend on precision of the tools. For example control systems with wheel velocity feedback can synchronize the rotation of wheels especially in straight motion or in rotation of the robot over its gravity center. Figure 12 is an illustration of unsynchronized wheels velocity effects on robot rotation during 360 degree rotation over its center. Point 1 is initial position and point 2 is its correspondent position after 360 degree of rotation as shown in Figure 12.
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ADVANCED ERROR RECOVERY FOR TMR SYSTEMS

ADVANCED ERROR RECOVERY FOR TMR SYSTEMS

The system is designed for the detection and recovery of multiple errors in TMR based systems for safety critical applications. It reuses the scan chain flip flops for the process of error detection and recovery. Here the roll forward error recovery technique is used in which the state of the fault free module is copied in to the faulty one. Thus a recovery of the same is done. Both comparison and recovery mode operate at same time, which in turn reduces the time delay. The scan chain flip flops are reused. So no additional circuitry is required for knowing the internal states. A comparison study of the system was made with existing ones. This comparison revealed that the technique uses only half the area used by the SMERTMR technique. The power consumption also reduced by 50%. Thus the design is an efficient one with less performance overhead. This fault recovery technique compares the three outputs to find the mismatch and recovers the faulty modules. Both operations are done at the same time, using same hardware. The design is developed and compiled to VHDL netlist. Finally, the optimally synthesized netlist of the integrated design is implemented into Xilinx Spartan 3e FPGA development board.
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Energy Recovery Simulation Research of Demolition Robot Rotation Hydraulic System

Energy Recovery Simulation Research of Demolition Robot Rotation Hydraulic System

As can be seen from figure 6, the overflow of the safety valve causes a large amount of energy dissipation on its valve opening. Higher peak power indicates greater hydraulic impact on the system. The empirical formula method can be used to preliminarily match the parameters of the accumulator, but the error and complexity of this method is large and there is no unique criterion. In this paper, the electromechanical and hydraulic combined simulation model of the rotary system has been established. On this basis, the parameters of the accumulator are preliminarily determined by means of simulation test. By integrating the relief valve overflow flow curve, it can be obtained that the overflow volume is about 0.5L. In order to fully absorb the oil volume during braking, the initial volume of the accumulator can be set to 3L primarily, and then the initial pressure can be selected according to the desired braking effect. Through multiple simulations, the initial pressure is temporarily set at 6MPa.
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Operator control hierarchy for multiple robot systems

Operator control hierarchy for multiple robot systems

For safely operating the robotic systems, two situations need to be considered. Conventionally, for a teleoperated robotic system like a rover or drone, the system is operated mutually exclus- ively, which means only one operator can control a single robotic system. The requirement of mutual exclusion brings two consequences. First, unpredictable behaviours occur when multiple operators try to control a same robotic system. Several control commands from the different operators exist in data link simultaneously. These control commands from different operators lead to unexpected behaviours. Second, when the only operator leaves the system due to a network or program error, or the operator quits intentionally, the remote robotic sys- tem will be left uncontrolled. This can also lead to unpredictable behaviours.
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The effect of detection and restoration times for error recovery in communication networks

The effect of detection and restoration times for error recovery in communication networks

Communication networks, like any other physical systems, are subject to failures. For this reason, net- works are built with special reliability provisions to handle faults. One form of provision is that of a standby resource when a failure occurs in the active resource, the system is switched to the standby re- source while the failed one is being repaired. From the time that a failure occurs until it is actually de- tected the system performs erroneously. In addition, the switching operation takes a nite amount of time during which system performance is degraded. In high-speed networks, the amount of information per unit time going through a transmission mediumis very large. A line failure will imply a large amount of infor- mation loss. A major concern in a high speed network- ing environment, is to keep detection and restoration times very small to minimize information loss.
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Error correction codes for molecular communication systems

Error correction codes for molecular communication systems

Applications in the medical and healthcare fields are the most important aspects that can be improved by MC [85], [86], [87]. Such MC system can be constructed using a group of nano-machines which can monitor the health conditions and perform a specific therapy by communicating with each other. The envisaged applications can be shown in the targeted drug delivery system [88], the healthcare monitoring system and the immune support system. In targeted drug delivery system, the drug molecules are encapsulated in a nano-capsule and propagated in the medium. This nano-capsule can be delivered to the target location under the guiding of the nano-machine located at the target side, and then the drug molecules are released. The targeted drug delivery system can reduce the influence of drugs on non-target areas. In healthcare monitoring system, a set of nano-sensors are placed at the target area in the body, and the information of target area can be delivered into another nano-robot to give a timely treatment, i.e. releasing drug molecules. On the other hand, these nano-robots can also communicate with macro/micro-machines which located outside of the body. Thus the information can be received by the observer. The immune system can be composed by several nano-machines, these nano- machines are injected into the body to protect the organism and destroy pathogens. Each nano-machine in the immune system has a specific task, for example, some of them can be used for finding pathogens, and some of them can destroy the pathogens.
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Don’t Worry, We’ll Get There: Developing Robot Personalities to Maintain User Interaction After Robot Error

Don’t Worry, We’ll Get There: Developing Robot Personalities to Maintain User Interaction After Robot Error

The synthetic personality a robot exhibits can have substantial impact on the user’s experience of, and their engagement with, HRI [3]. The relatively new so- cial domain of HRI is unfamiliar to many, but principles of social psychology have been applied to social HRI scenarios with promising results. These include: accu- rate recognition of synthetic personality types, even in non-humanoid robots [6]; development of classification of social ‘rules’ for robots to adhere to [3]; and par- ticipant response towards synthetic personalities corresponding with theoretical models of interpersonal cooperation [2]. This paper draws on social psychologi- cal theories to develop a model of social factors for robots that support recovery from robot error and maintain user interaction.
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Calibration of Industrial Robot Kinematics Based on Results of
Interpolating Error by Shape Function

Calibration of Industrial Robot Kinematics Based on Results of Interpolating Error by Shape Function

Today, robotic arms play an important role in industrial applications. The accuracy of these manipulators should be maintained over time to ensure product quality. As such, many studies have been conducted to improve the calibration and maintain the desired accuracy of robot grippers. These studies are classified into two methods: model-based and modeless. The classical model-based method for robot calibration involves setting up a kinematic model for the robot, measuring positions and orientations of the robot end-effector, identifying its kinematic parameters and compensating its pose errors by modifying its joint angles (Mooring et al., 1991). The advantage of model-based calibration is that a large workspace can be calibrated accurately and all pose errors within the calibrated workspace can be compensated by joint angles (Bai and Wang, 2006). Therefore, a significant amount of research has been performed in this direction. Several recently published studies-such as that by Wang et al. (2012) used genetic algorithms to build mathematically calibrated equations to compensate the kinematic errors cylindrical-coordinate-based manipulator with three Degrees of Freedom (DOF). Ma et al. (2018) conducted modelling and calibration of high-order joint-dependent kinematic errors for industrial robots. The process was performed using high-order Chebyshev polynomials to represent individual error terms and a laser tracker system to acquire the measured data. Laser tracker systems are often used in studies of kinematic error calibration of
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Collaboration in multi robot systems

Collaboration in multi robot systems

Zhang et al. [33] presented a multi-robot task allocation method for exploring unknown environments. The authors used the virtual pheromone self-organizing logic, inspired by the ant colony, to indicate the difficulty of the explored areas. Xu et al. [34] presented a Modified Ant Colony System algorithm to solve a constrained multiple traveling salesman problem and applied to the multi-robot dynamic task allocation problem. The proposed algorithm put all ants on the starting or ending depots of robots randomly. Besides, the pheromone and the cost from one depot to all targets are calculated and stored. In the proposed algorithm an initial task allocation is run by a leader robot, while the result of allocation is sent to each robot in the system. Task reallocation is performed in case of conduct failures. Shi et al. [35] presented a reputation-based task allocation model to solve the task allocation problem in collaborative multi-robot system. The study considered the “reputation” of a robot by assigning a specific task to the robot with high reputation. According to the authors, this will improve the success rate of implementation of its mandate, thereby reducing the time of the system task recovery and redistribution. However, in this method, the robots with the highest reputation values will handle most of the load. As a result, the low contribution of the other robots may decrease the efficiency of the system. Tolmidis et al. [36] proposed a solution for the multi-robot dynamic task allocation problem. In their study, the authors used multi- objective optimization for estimation and making offer for task assignment. The study aims to better utilize resources
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Determination of optimal samples for robot calibration based on error similarity

Determination of optimal samples for robot calibration based on error similarity

using a single camera was developed for robot calibration methods and systems. 13 The Levenberg–Marquardt algorithm was used to identify the 25 unknown parameter errors described by the MD-H model. 14 Neural networks were also used to improve the poisoning accuracy of robot manipula- tors. 15 Park et al. 16 employed a stationary camera and a structured laser module (SLM) attached on a robot’s end effector to measure the accurate position of the robot. 16 Several observability indexes were promoted to measure the goodness of a pose set based on analyzing the effects of noise and variance of parameters. 17
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Efficient Spatial Data Recovery Scheme with Error Refinement for Cyber physical Systems

Efficient Spatial Data Recovery Scheme with Error Refinement for Cyber physical Systems

In this section, we conduct the simulation studies to evaluate our proposed ESDR/ER scheme on deterministic and stochastic traffic pattern of CPS. We compare our proposed ESDR/ER scheme to the ESDR, WP algorithm [22] and the STI approach [17]. For deterministic traffic pattern, we conduct an experiment to measure the inside temperature of the master bedroom in the iHouse facility which is in situated Nomi city in Japan. The room is equipped with eight sensors at eight corners. The measurement is taken in every two minutes for twenty-four hours. All the sensors forward their data to reach the base station in single radio hop through the simplest spanning tree topology routing protocol. For stochastic traffic pattern, we create a simulation environment with five sensor and generate data series using autoregressive (AR) model in MATLAB simulator. We also add some random noise with each series to it make more realistic. Based on the collected information, we investigate the performance of our proposed scheme using a MATLAB. In this simulation, we assume that the single sensor produces a missing sensed data when it transmits its packet to the base station. We randomly delete the data according to the percentage of missing data from the original set and recover them using the aforementioned data recovery algorithms. We use the root mean square error (RMSE), mean absolute error (MAE) and integral of absolute error (IAE) to evaluate the performance of the said algorithms.
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Case study of error recovery and error propagation on ranger

Case study of error recovery and error propagation on ranger

We would like to thank the Texas Advanced Comput- ing Center (TACC) for providing the Ranger cluster log data and granting access to their systems administrators. We also thank Karl Solchenbach (Intel Corporation, Europe) for granting access to his research scientists. This research is supported by The Alan Turing Institute under the EPSRC grant EP/N510129/1, The Alan Turing Institute-Intel partnership and the National Science Foundation under OCI awards #0622780 and #1203604 to TACC at the University of Texas at Austin.

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A  Key  Recovery  Attack  on  Error  Correcting  Code  Based  a  Lightweight  Security  Protocol

A Key Recovery Attack on Error Correcting Code Based a Lightweight Security Protocol

In this paper, we have investigated security of the lightweight RFID protocol CMC and presented two at- tacks namely the tracking and the key recovery attacks. By launching the former we have demonstrated that an adversary may have non-negligible advantage in distinguishing the tags, so it is addressed that the target protocol cannot ensure untraceability property. In addi- tion to this, the latter attack blows up the whole security claims of the protocol and secret key of a selected tag can be extracted in practical time depending on the adopted linear block code. Although use of error cor- recting codes alleviate load of the reader in computation process and they can be implemented easily at the tag side, linearity characteristic of these codes are exploited in our attack strategy. Indeed apart from examination of RFID security systems, our proposed attack calls
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Teamwork for Multi-Robot Systems in Dynamic Environments

Teamwork for Multi-Robot Systems in Dynamic Environments

Abstract: The increasing number of robots around us will soon create a demand for connecting these robots in order to achieve goal-driven teamwork in heterogeneous multi-robot systems. In this paper, we focus on robot teamwork specifically in dynamic environments. While the conceptual modeling of multi-agent teamwork has been studied extensively during the last two decades, related engineering concerns have not received the same degree of attention. Therefore, this paper makes two contributions. The analysis part discusses general design challenges that apply to robot teamwork in dynamic application domains. The constructive part presents a review of existing engineering approaches for challenges that arise with dynamically changing runtime conditions. An exhaustive survey of robot teamwork aspects would be beyond the scope of this paper. Instead, we aim at creating awareness for the manifold dimensions of the design space and highlight state-of-the-art technical solutions for dynamically adaptive teamwork, thus pointing at open research questions that need to be tackled in future work.
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Secure self-recovery watermarking scheme for error concealment and tampering detection

Secure self-recovery watermarking scheme for error concealment and tampering detection

This paper presents a secure variable-capacity self- recovery watermarking scheme. In the proposed scheme, it is possible to implement both an error concealment algorithm and a tampering detection algorithm. The scheme is based on watermarking and halftoning tech- niques. In order to increase the data hiding capacity, this work proposed a simple modification of the QIM water- marking algorithm. To obtain higher quality restored areas, improved inverse halftoning algorithms are also proposed. A secret key code is embedded to the host content to identify the spatial and temporal positions of tampered regions, taking advantage of the lower sensitiv- ity of the HVS to degradations in the blue color chan- nel. Above all, the proposed scheme not only achieves variable-capacity, higher security, higher detection accu- racy, and strong recovery ability but also can resist collage attack and mean attack.
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A packet error recovery scheme for vertical handovers mobility management protocols

A packet error recovery scheme for vertical handovers mobility management protocols

Tetrys adds the packets to its encoding window and re-injects them (step 3 and 4) adding a packet sequence number (three bytes might be more than necessary) plus a bit to distinguish red[r]

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A Novel Approach Railway Track Error Detection Robot Using GPS Technology

A Novel Approach Railway Track Error Detection Robot Using GPS Technology

The finding of cracks in railways tracks takes time consumption due to manual checking. It reduces the accuracy too. This method of design is having limited intelligence and time consuming. Aliterature survey on the existing techniques for crack detection reveal a number of sophisticated and accurate crack detection technologies.First, in the Indian rails, typically there are small gaps in the rail tracks to provide for thermal expansion during the summer. This design is provided so as to ensure that the track does not twist or crack due to the heat. When the existing technique of crack detection was implemented, it was found that the system was giving false positive signals; that is, it was counting the thermal gaps as cracks. Another issue faced during practical implementation is the presence of railway bifurcations. If the mechanical design of the robot is unsuitable, then it will have a tendency to either get stuck in these bifurcations or in worst case even fall out of the tracks.
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An Opportunistic Error Correction Layer for OFDM Systems

An Opportunistic Error Correction Layer for OFDM Systems

In the current generation of WLAN equipment (based on IEEE 802.11a [6]), the forward error-correction (FEC) layer is based on rate compatible punctured codes (RCPC). These codes have good performance for random bit-errors, but poorer performance for burst bit errors. For that reason, an interleaver is applied to randomize the burst errors of the wireless channel. On the other hand, the wireless channel is changing in time. This means that some packets are received with a “good” channel and others over a “bad” channel. The error-correction layer based on RCPC has been designed in such a way that for most channel realizations the bit-error rate (BER) is zero. For a small part of the channel, bit errors will occur and retransmission is necessary. Although this solution works well in practical systems, it is not energy- e ffi cient for two reasons.
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