| The marriage of a novel, micromachined multisensor chip, and current sensor fusion concepts from the robotics field is described in this work. The microsensor node created, embodied the key concepts of redundancy, diversity and unity, the heart of sensor fusion. Through extension of these concepts to the microscale, a deeper meaning for redundancy was realized. A microchip containing arrays of sensors (potentially thousands of sensors) was created. Through extension of these concepts to environmental measurands, a deeper understanding of diversity was gained. Cross-sensitivities of sensor elements were treated as an advantage, not something to be "compensated out". A sensor system design hierarchy was developed and followed to illustrate unity. The dependance of a successful system on the sensor package was emphasized. Extension of sensor fusion concepts to extraneous measurands resulted in a physical basis for identification, and partial to complete compensation of packaging deficiencies.;There were two main thrusts to the project: (1) the design and development of a multisensor microchip containing a carefully chosen, diverse set of sensor elements, and (2) the design and development of microsensor fusion concepts, software, and hardware for enhanced reliability and information content. The Microsensor Fusion Chip that was designed and fabricated, contain 22 sensor elements of 6 different types (with 8 modes of operation). Diverse physical devices and phenomena including diodes, polysilicon, high resistivity single crystal silicon convection from a heated surface, photoconductivity, etc. were utilized by the sensing elements of this chip. Arrays of each type, containing from 2 to 8 individual elements, were integrated into the chip. The Z-World microcontroller system was developed to control the pulsing sequence of the power supplies, as well as to perform the functions of pre-conditioning, amplification, multiplexing, and analog-to-digital conversion. The far reaching goal of integration of sensors and microcontroller at the chip level was kept in mind during the design phase. This system served as the research vehicle for experimentation with environmental measurands (pressure and temperature), as well as extraneous measurands (light and flow). |
