We propose a novel approach for modeling the end-to-end time-delay dynamics of the Internet using system identification, and apply it to control real-time telerobotic operations via Internet with specific Quality of Service (QoS) offerings. To do this, we have employed system identification techniques and the ARX model to obtain the values of relevant parameters and study their dynamics. The results show a periodic behavior of the Internet delay. Experimental measurements show the accuracy and usefulness of our theoretical derivations.

AbshocC We introduce a new multivariable control method for real-time telerobotie operations via the Internet. Random communications delay of the Internet can cause instability in real-time closed-loop telerobotic systems. When a single identification model is used, it will have to adapt itself to the operating condition before an appropriate control mechanism can be applied. Slow adaptation may result in a large transient error. As an alternative, we propose to use a Multiple Model framework. The control strategy is to determine the best model for the current operating condition and activate the corresponding controller. We propose the use of Multi-Model Adaptive Control Theory and Multivariable Wave prediction method to capture the coneurreucy and complexity of Internet-based teleoperation. I. INTRODUCnONEMOTE control of a plant or machine from far R distance and via a medium environment is called teleoperation. The distance can vary from tens of centimeters (micromanipulation) to millions of kilometers (space applications). Teleoperation takes several forms and can he done via any communication medium. Recently, the main focus has been on teleoperation via the Intemet. Motivated by the availability, widespread access, and low cost of the Intemet, many researchers have focused on the Intemet-based teleoperation.Since the Intemet introduces random communication delays, several challenges and difficulties, such as loss of transparency, and desynchronization in real-time closedloop telerohotic systems, may arise. In order to meet these challenges, a general and efficient modeling and analysis tool for the Intemet delay needs to he developed. Several techniques have heen proposed to compensate for this effect, such as a time forward observer developed for a supervisoly control over the Intemet by Brady and Tam [I]-[3], a position-based force-feedback scheme implemented by Oboe and Fiorini [4], and a wave variable based technique developed by Niemeyer and Slotine [5]. The methods in [l] and [4] require knowledge of the remote plant, but the method in [5] does not. Due to possible uncertainties on the remote plant, the methods that require the knowledge of remote plant may not he applicable in all cases. The stability of such techniques may depend on the accuracy of knowledge on the remote plant. As such, the wave-based method has an advantage from this point of view, hut may suffer from poor performance for delays significantly longer than the time constant(s) of the system. Wave variables were first introduced by Anderson and Spong [6]-[7], and were later presented in a more intuitive, physically motivated, passivity-based formalism by Niemeyer and Slotine [5]-[SI. Later the use of wave variables was extended to variable delay [9]-[10], as is the case for the Intemet. Nevertheless, performance degradation for prolonged time delays is still a serious issue.The rest of this paper is organized as follows. In Section n, we explain the wave variable method as well as the Smith predictor. In Section 111, the multivariabl...

No abstract

No abstract

Companies are struggling in a highly competitive environment to accelerate their operations and operations. Discussions such as globalization and the expansion of networks such as the Internet are important issues that affect the resources, marketing, and other issues that companies engage with. The effects of information technology in industries, in the supply chain areas and in the value chain, are evident from the relationship with suppliers to production and communication with customers, including the impact of information technology on the supply chain performance. The purpose of this study was to investigate the relationship between information technology variables, integration and flexibility function in the automotive supply chain and the effect that information technology has on the supply chain performance. After collecting the data through a questionnaire from automobile manufacturers and analysis of the obtained model, the results show that the information technology which in this research includes the Internet, the organization's network systems and combine system has a positive and direct effect on integration and flexibility. These results indicate that the use of information technology increases the integrity and flexibility of supply chain components and improves communication between them.