Preliminary Research Of Evolvable Sensor Based On Evolvable Hardware

With rapidly development of information technology, the demand of highintelligentized characteristics to sensor becomes increasingly improved. For onething, to enhance the information collection precision and processing speedrequest that the current pre-processing technology need to be more smart toeliminate useless/redundant data collected from sensors, which can improve thequality of sensor. For another, it is cried for the sensor to adjust circuit structureself-adaptively without experience or manual intervention and to self-repair thedamages or aging, if sensing circuit wants to be more highly stable andfault-tolerant, under special conditions or extreme environments, to ensure thatthe sensor will keep the best performance steadily.An effective solution of these problems is to put the principle of EvolvableHardware (EHW) based on programmable device and Genetic Algorithm (GA)to automatically evolve method and adaptively re-configurable, self-tolerantresearch of sensor, that is evolvable sensor. There are few researches to this areacurrently. This paper presents the preliminary research on evolvement of sensorand its key component circuit: active filters. The main works are as follow:1. A framework of evolvable sensor is proposed based on combining the characteristics of conventional sensor and the technology of EHW, whichcomplete the preparation of the further research on evolvable sensor.Subsequently, integrated with the hierarchical coding characteristic of GA, ahierarchical structure design method which suits the evolvement of analogsensor circuit is proposed.2. The evolution process of Field Programmable Gate Array is simulated bymaking use of GA, and a specific input/output response is realized, anticipatedtarget is achieved and we obtain the ideal result. The equipment of the evolutionand the result reveal the characteristics of GA in the research of EHW, and theproblems of basic GA to be improved. All these work has great significance forthe evolution of analog circuit and the algorithm designing.3. In view of the importance of filter component to active sensor circuit,four kinds of second order active filters such as LPF, HPF, BPF and BEF areevolved in the usage of an improved elitist preserving and adaptive GA. Theexperiments prove that, analog circuit filters can be evolved effectively thatconforms to the request well. As well, the Nominal Value is used in the work tothe amendment and correction of evolved circuit parameters, which attempt themeaningful explore to the entire design of the evolvable sensor and thetransform from EHW theory based on analog circuit to practical application.