Purpose-The purpose of this paper is to describe the use of simple expert systems to improve the performance of tele-operated mobile robots and ultrasonic sensor systems. The expert systems interpret data from the joystick and sensors and identify potentially hazardous situations and then recommend safe courses of action so that tele-operated mobile-robot tasks can be completed more quickly. Design/methodology/approach-The speed of a tele-operator in completing progressively more complicated driving tasks is investigated while using a simple expert system. Tele-operators were timed completing a series of tasks using a joystick to control a mobile robot through a simple expert system that assisted them with driving the robot while using ultrasonic sensors to avoid obstacles. They either watched the robot while operating it or sat at a computer and viewed scenes remotely on a screen from a camera mounted on the robot. Tele-operators completed tests with the simple expert system and the sensors connected. The system used an umbilical cable to connect to the robot. Findings-The simple expert systems consistently performed faster than the other systems. Results are compared with the most recently published results and show a significant improvement. In addition, in simple environments, tele-operators performed better without a sensor system to assist them but in more complicated environments than tele-operators performed better with the sensor systems to assist. Research limitations/implications-Simple expert systems are shown to improve the operation of a tele-operated mobile robot with an obstacle avoidance systems fitted. Practical implications-Tele-operated systems rely heavily on visual feedback and experienced operators. This paper investigates how to make tasks easier. Simple expert systems are shown to improve the operation of a tele-operated mobile robot. The paper also suggests that the amount of sensor support should be varied depending on circumstances. Originality/value-The simple expert systems are shown in this paper to improve the operation of a tele-operated mobile robot. Tele-operators completed tests with the simple expert system and the sensors connected. The results are compared with a tele-operator driving a mobile robot without any assistance from the expert systems or sensors and they show a significant improvement.

The protocol data rate governing data storage devices will increase to over 12 Gb/s by 2013 thereby imposing unmanageable cost and performance burdens on future digital data storage systems. The resulting performance bottleneck can be substantially reduced by conveying high-speed data optically instead of electronically. A novel active pluggable 82.5 Gb/s aggregate bit rate optical connector technology, the design and fabrication of a compact electro-optical printed circuit board to meet exacting specifications, and a method for low cost, high precision, passive optical assembly are presented. A demonstration platform was constructed to assess the viability of embedded electro-optical midplane technology in such systems including the first ever demonstration of a pluggable active optical waveguide printed circuit board connector. High-speed optical data transfer at 10.3125 Gb/s was demonstrated through a complex polymer waveguide interconnect layer embedded into a 262 mm 240 mm 4.3 mm electro-optical midplane. Bit error rates of less than and optical losses as low as 6 dB were demonstrated through nine multimode polymer waveguides with an aggregate data bandwidth of 92.8125 Gb/s.

Purpose -The paper aims to propose a system that uses a combination of techniques to suggest weld requirements for ships parts. These suggestions are evaluated, decisions are made and then weld parameters are sent to a program generator. Design/methodology/approach -A pattern recognition system recognizes shipbuilding parts using shape contour information. Fourier-descriptors provide information and neural networks make decisions about shapes. Findings -The system has distinguished between various parts and programs have been generated so that the methods have proved to be valid approaches. Practical implications -The new system used a rudimentary curvature metric that measured Euclidean distance between two points in a window but the improved accuracy and ease of implementation can benefit other applications concerning curve approximation, node tracing, and image processing, but especially in identifying images of manufactured parts with distinct corners. Originality/value -A new proposed system has been presented that uses image processing techniques in combination with a computer-aided design model to provide information to a multi-intelligent decision module. This module will use different criteria to determine a best weld path. Once the weld path has been determined then the program generator and post-processor can be used to send a compatible program to the robot controller. The progress so far is described.

PurposeThe purpose of this paper is to investigate how to make powered‐wheelchair driving easier using simple expert systems to interpret joystick and ultrasonic sensor data. The expert systems interpret shaky joystick movement and identify potentially hazardous situations and then recommend safe courses of action.Design/methodology/approachThe way that a human user interacts with a powered‐wheelchair is investigated. Some simple expert systems are presented that interpret hand tremor and provide joystick position signals for an ultrasonic sensor system. Results are presented from a series of timed tasks completed by users using a joystick to control a powered‐wheelchair. Effect on the efficiency of driving a powered‐wheelchair is measured using the times to drive through progressively more complicated courses. Drivers completed tests both with and without sensors and the most recently published systems are used to compare results.FindingsThe new expert systems consistently out‐performed the most recently published systems. A minor secondary result was that in simple environments, wheelchair drivers tended to perform better without any sensor system to assist them but in more complicated environments then they performed better with the sensor systems.Research limitations/implicationsThe time taken for a powered‐wheelchair to move from one place to another partly depends on how a human user interacts with the powered‐wheelchair. Wheelchair driving relies heavily on visual feedback and the experience of the drivers. Although attempts were made to remove variation in skill levels by using sets of data associated with each driver and then using paired statistical tests on those sets, some variation must still be present.Practical implicationsThe paper presents new systems that could allow more people to use powered‐wheelchairs and also suggests that the amount of sensor support should be varied depending on circumstances.Originality/valueThe new systems described in the paper consistently performed driving tasks more quickly than the most recently published systems.

Awareness of environmental issues has led to increasing interest from composite researchers in using “greener” materials to replace synthetic fiber reinforcements and petrochemical polymer matrices. Natural fiber bio-based thermoplastic composites could be an appropriate choice with advantages including reducing environmental impacts, using renewable resources and being recyclable. The choice of polymer matrix will significantly affect the cost, manufacturing process, mechanical properties and durability of the composite system. The criteria for appropriate monomers are based on the processing temperature and viscosity, polymer mechanical properties, recyclability, etc. This review considers the selection of thermoplastic monomers suitable for in situ polymerization during resin, now monomer, infusion under flexible tooling (RIFT, now MIFT), with a primary focus on marine composite applications. Given the systems currently available, methyl methacrylate (MMA) may be the most suitable monomer, especially for marine composites. MMA has low process temperatures, a long open window for infusion, and low moisture absorption. However, end-of-life recovery may be limited to matrix depolymerization. Bio-based MMA is likely to become commercially available in a few years. Polylactide (PLA) is an alternative infusible monomer, but the relatively high processing temperature may require expensive consumable materials and could compromise natural fiber properties.

PurposeThis paper aims to describe real time improvements to the performance and trajectories of robots for which paths had already been planned by some means, automatic or otherwise. The techniques are applied to industrial robots during the gross motions associated with pick and place tasks. Simple rules for path improvement are described.Design/methodology/approachThe dynamics of the manipulator in closed form Lagrange equations are used to represent the dynamics by a set of second‐order coupled non‐linear differential equations. The form of these equations is exploited in an attempt to establish some simple rules. Sub‐optimal paths are improved by considering simple rules developed from the model of the machinery dynamics. By considering the physical limitations of the manipulator, performance was improved by refining pre‐calculated paths. Experiments were performed with a prototype robot and an old Puma 560 robot in a laboratory environment. Once the method had been tested successfully then experiments were conducted with a Kuka KR125 Robot at Ford Motor Company. The measured quantities for all the robots were drive currents to the motors (which represented the torques) and the joint angular positions.FindingsThe method of path refinement presented in this paper uses a simplified model of the robot dynamics to successfully improve the gross motions associated with a pick and place task. The advantage of using the input‐output form described was that intermediate non‐linearities (such as gear friction) and the motor characteristics were directly incorporated into the model.Research limitations/implicationsEven though many of the theoretical problems in manipulator dynamics have been solved, the question of how to best apply the theories to industrial manipulators is still being debated. In the work presented in this paper, information on system dynamics is used to produce simple rules for “path improvement”.Practical implicationsMost fast algorithms are for mobile robots and algorithms are scarcer for manipulators with revolute joints (the most popular type of industrial robot). This work presents real time methods that allow the robot to continue working while new global paths are automatically planned and improved as necessary.Originality/valueMotion planning for manipulators with many degrees of freedom is a complex task and research in this area has been mostly restricted to static environments, offline simulation or virtual environments. This research is applied in real time to industrial robots with revolute joints.

Self-heating of nanocomposite materials based on the joule heating effect is suitable for numerous engineering applications. In this study, a highefficiency self-heating nanocomposite, using high conductive multi-walled carbon nanotubes (MWCNTs)-based phenolic resin, was fabricated with a hot press method. The microstructure and the thermal stability of self-heating nanocomposite were studied by X-ray diffraction, scanning electronic microscopy, and thermogravimetric tests. Electromechanical and thermal performance tests were conducted to investigate their potential as a self-heating application. Results showed that the compressive strength, modulus, and the piezo-resistive behaviour were higher after adding MWCNTs to the phenolic resin, indicating better load transfer and self-damage sensing as well. Moreover, at 4.0 wt% of MWCNTs concentration, the electrical conductivity of a self-heating nanocomposite showed a higher value of 13.26 S/m which was also found to be proportionally increased with the thickness of the samples, it was ≈25.5 and ≈12.8 S/m for 10 and 3 mm, respectively. In addition, a steady-state temperature of ≈110°C could be reached at low applied volts (8 V) as well as its heating performance was significantly dependent on the input power and the thickness of the sample. This is also confirmed by statistical results between the sample with thicknesses of 3 and 10 mm in terms of power consumption with P value ≈ .0001. Furthermore, the influence of Joule heating was estimated analytically based on the one-dimensional heat transfer equation in companying with other previous models. The estimated distributed temperatures values were in good agreement with the experimental results. The selfheating nanocomposite described in this study has the potential to be used in various industrial applications and a wide range of sectors due to its ability to self-damage sensing, easy fabrication, and high heating efficiency at low power consumption.

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