John R. G. Pretlove

Environmental performance indicators for integrated supply chains: the case of Xerox Ltd

The Integrated Supply Chain at Xerox Ltd is a large complex organisation which has many potential impacts on the environment. In order to better understand and reduce those impacts, an environmental bias has been introduced into the decision making process which allows more environmentally conscious decisions to be made. This paper details how the environmental bias was developed and how it can be used to provide both a measure of environmental performance for the whole supply chain, each functional element within the chain and for different product delivery scenarios. The environmental decision making tool construction is discussed and preliminary results show that it is the working life of a typical product which causes the biggest environmental impact.

LOGISTICS PERFORMANCE MEASUREMENT AND GREENING SUPPLY CHAINS: DIVERGING MINDSETS

Although there has been considerable effort placed on measuring supply chains in order to assess their performance, these techniques have been found to be time and cost focused, aimed at coping with rapid change. This approach tends to have a short‐term outlook. Work on greening supply chains is much longer‐term in outlook. Is information intensive and biased towards the supply side? These two mindsets appear to be diverging, developing in conflicting directions. This is an alarming prospect for the environment, which has no place in future supply chain performance measurements, thus running the risk of being increasingly side‐lined; and for performance measurements, which is unconcerned with longer‐term sustainability in terms of the environment. The case is made to amalgamate the advantages of both schools of thought to allow long‐term views to be represented by short‐term performance measurement.

Augmented reality as a tool to aid the telerobotic exploration and characterization of remote environments

The three-dimensional characterization and mapping of remote environments is an important task that generates a good deal of attention both by end users and by researchers across several fields of interest. In the mobile robotics community, a great deal of work has been done in equipping vehicles with sensors that can acquire three-dimensional and even multimodal information about the location and nature of features and objects in remote environments. However, the interpretation of such data using fully autonomous methods, such as computer vision, is usually a highly complex problem that, we believe, is much better suited to a humanoriented solution. In this paper, we describe our work in the development of augmented reality (AR) techniques for the telerobotic inspection and characterization of remote environments. We describe how we are using stereoscopic camera feedback from a remote vehicle and equipping the human operator with three-dimensional virtual cursors that can be used to interactively measure and model real features and objects in the remote environment. We include a description of the calibration techniques used to correctly align the real and virtual images both statically and under vehicle and camera motion. We also describe how we are using our system to demonstrate the potential of AR for improving the inspection of underground sewer pipes.

Augmented reality for underground pipe inspection and maintenance

The University of Surrey is engaged in developing augmented reality systems and teleoperation techniques for enhanced visual analysis and task performance in hostile environments. One particular current project in the UK is addressing the development of stereo vision systems, augmented reality, image processing techniques and specialist robotic vehicles which may be used for the future examination and maintenance of underground sewage pipes. This paper describes the components of the stereo vision and augmented reality system and illustrates some preliminary results of the use of the stereo robotic system mounted on a mobile laboratory vehicle and calibrated using a pin-hole camera model.

Augmenting reality for telerobotics: unifying real and virtual worlds

This paper describes the Active Telepresence System and the development of an augmented reality (AR) interface to enhance the operator’s sense of presence in hazardous environments. The initial enhancements to the user interface are a virtual instrument panel to aid navigation in a variety of viewing conditions and a virtual cursor that provides a means for the operator to interact with the remote environment. The results of preliminary experiments using the initial enhancements are discussed.

The Surrey attentive robot vision system

This paper presents the design and development of a real-time eye-in-hand stereo-vision system to aid robot guidance in a manufacturing environment. The stereo vision head comprises a novel camera arrangement with servo-vergence, focus, and aperture that continuously provides high-quality images to a dedicated image processing system and parallel processing array. The stereo head has four degrees of freedom but it relies on the robot end-effector for all remaining movement. This provides the robot with exploratory sensing abilities allowing it to undertake a wider variety of less constrained tasks. Unlike other stereo vision research heads, the overriding factor in the Surrey head has been a truly integrated engineering approach in an attempt to solve an extremely complex problem. The head is low cost, low weight, employs state-of-the-art motor technology, is highly controllable and occupies a small-sized envelope. Its intended applications include high-accuracy metrology, 3-D path following, object recognition and tracking, parts manipulation and component inspection for the manufacturing industry.

Augmented reality and stereo vision for remote scene characterization

In this paper we present our progress in the research and development of an augmented reality (AR) system for the remote inspection of hazardous environments. It specifically addresses one particular application with which we are involved--that of improving the inspection of underground sewer pipes using robotic vehicles and 3D graphical overlays coupled with stereoscopic visual data. Traditional sewer inspection using a human operator and CCTV systems is a mature technology--though the task itself is difficult, subjective and prone to error. The work described here proposes not to replace the expert human inspector--but to enhance and increase the information that is available to him and to augment that information with other previously stored data. We describe our current system components which comprise a robotic stereo head device, a simulated sewer crawling vehicle and our AR system. We then go on to discuss the lengthy calibration procedures which are necessary in to align any graphical overlay information with live video data. Some experiments in determining alignment errors under head motion and some investigations into the use of a calibrated virtual cursor are then described.

Design of a high-performance telepresence system incorporating an active vision system for enhanced visual perception of remote environments

This paper describes the design, development and implementation of a telepresence system for hazardous environment applications. Its primary feature is a high performance active stereo vision system slaved to the motion of the operators head. To simulate the presence of an operator in a remote, hazardous environment, it is necessary to provide sufficient visual information about the remote environment. The operator must be able to interact with the environment so that he can carry out manipulative tasks. To achieve an enhanced sense of visual perception we have developed a tightly integrated pan and tilt stereo vision system with a head-mounted display. The motion of the operators head is monitored by a six DOF sensor which provides the demand signals to servocontrol the active vision system. The system we have developed is a compact yet high performance system employing mechatronic principles to deliver a system that can be mounted on a small mobile platform. We have also developed an open architecture controller to implement the dynamic, active vision system which exhibits dynamic performance characteristics of the human head-eye system so as to form a natural and intuitive interface. A series of tests have been conducted to establish the system latency and to explore the effectiveness of remote 3D human perception, particularly with regard to manipulation tasks and navigation. The results of these tests are presented.

From supervisory control to cooperative control

This paper reviews different forms of human and computers co-operative control in teleoperation. The need to define a new form of co-operative control is addressed due to the increase capabilities of computers in perception, decision- making and learning. A brief description of shared and traded control and supervisory control is given with their differences from co-operator control. A co-operative control concept based on the less strict sense of supervisory control is proposed. In this concept, human operators and computers can interact and co-operate in the operation at both intelligence and execution levels. Humans and computers distinctive and overlapping advantages are utilized in the control concept. A framework for developing co-operative control systems is introduced with functional components depicted. A telerobotic system with a demonstration task has been developed as the test-bed to investigate different issues of co-operative control. The task description and operational mode of the system are also given.

Development of a Polhemus-based telemanipulation system

A polhemus-based telemanipulation system is being developed and tested in the Mechatronic System and Robotics Research group at the University of Surrey. This system provides a natural and intuitive operator input and easy remote control of a robot manipulator. The technique developed in this system will be applied to a telepresence system which has been developed in the research group for performing teleoperations in an unstructured remote and potentially hazardous environments. In this paper, the overview of the system architecture is provided. Some experiments have been conducted to evaluate this telemanipulation system and the evaluation and experimental results are presented.