| At present,there is an urgent need to provide network access to the massive heterogeneous "things",which aims to achieve the goal of IOE(Internet of Everything)with the big picture of interactions from people to people,things to things,and people to things.By drawing from the definition of "things" described in IEEE1451,and the definition of ubiquitous object proposed by Kulkarni,in this thesis we call the above "things" as UO(ubiquitous object),which are interactive objects connecting the digital world to the physical world.Due to the wide variety of UOs and communication protocols,it is a complicated process for UO to have Internet access.Even developing a simple application,developers of IOT should be equipped with systematic knowledge of electronic circuits,embedded devices and WEB systems.Currently,there is no effective plug-and-play unified access scheme to reduce the workload of third-party developers and make it convenient for ordinary users.The traditional access scheme represented by USB scheme focuses on performance,and is not suitable for low-power IoT scenarios.And the address recognition in the ?PnP scheme relies on the accuracy of the resistor,which is not convenient for third-party developers to develop.In order to solve the above problems,in this thesis we have completed the following work:(1)After making a survey of the plug-and-play unified access scheme of IOT,this thesis proposes a plug-and-play unified access scheme for UO based on low-energy,low-cost MCU(Microcontroller Unit).We design the architecture,physical topology and software development method of access system with this scheme.(2)We design and implement the functional modules of each layer in the access system.For the hardware components,this thesis designs and implements UO board circuit and control identification board circuit which aims to solve the problems of the coding and identification of UO,deficiency of MCU pin and high energy consumption..For the software components,the platform layer,object access layer and ubiquitous object layer of the system are designed and implemented,and the definition of the third party access process is given.(3)For the driver scheduling problem,a multi-objective optimization mathematical model based on the least common multiple of cycle was proposed,and the model was solved through NSGA-II.The validity of the model has been demonstrated through the analysis and comparison of experiments.(4)By testing the function of the scheme,comparing with other scheme and applying it to a waste mineral oil recovery unit,the effectiveness and practicability of the access scheme are demonstrated.After implementing the access scheme and system,the following effects are achieved:(1)Unified Plug-and-Play access schemes for UO is realized to reduce the difficulty of third-party development and utilization.For developers,the ?PnP address mark problem is solved,and hardware work only includes connecting UO signal line to the UO board;software work only includes the development of UO driver,without the complicated circuit and MCU main module implementation.For ordinary users,the use of UOs can be achieved with basic configuration or even without configuration.(2)Reduction in energy consumption and service life extension.To reduce energy consumption,EEPROM is only powering on once in the identification stage of address recognition process when the UO board plug into control identification board.By setting energy consumption minimization as one of the goals of driver scheduling problem,energy consumption of executing scheme can be reduced.Comparison tests show low energy consumption compared to the USB scheme.(3)Reducing delay and improving real-time performance.In order to reduce the delay of driver scheduling,delay minimization has been considered as one of the scheduling objectives.The computation of NSGA-II algorithm has been offloaded to the edge server to reduce the MCU computing overhead and delay. |
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