For meeting the demands of cost and size for micronavigation system, a combined attitude determination approach with sensor fusion algorithm and intelligent Kalman filter (IKF) on low cost Micro-Electro-Mechanical System (MEMS) gyroscope, accelerometer, and magnetometer and single antenna Global Positioning System (GPS) is proposed. The effective calibration method is performed to compensate the effect of errors in low cost MEMS Inertial Measurement Unit (IMU). The different control strategies fusing the MEMS multisensors are designed. The yaw angle fusing gyroscope, accelerometer, and magnetometer algorithm is estimated accurately under GPS failure and unavailable sideslip situations. For resolving robust control and characters of the uncertain noise statistics influence, the high gain scale of IKF is adjusted by fuzzy controller in the transition process and steady state to achieve faster convergence and accurate estimation. The experiments comparing different MEMS sensors and fusion algorithms are implemented to verify the validity of the proposed approach.

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Given the burgeoning demand for a small, lightweight, consume very little power, low-cost high performance inertial Measurement Units(IMU), test methods are necessary to evaluate the current state of the available of Micro-Electro-Mechanical Systems(MEMS) technology. A reliable and efficient calibration and testing method for evaluating the performance of MEMS IMU is developed, by virtue of MEMS sensor suffering from various errors that have to be calibrated and accomplished to get acceptable navigation results. A prototype development board based on FPGA, dual core processor's configuration for IMU/INS/GPS integrated navigation system is designed for experimental tests. According to the MEMS IMU developed, static tests, rate tests, thermal tests are implemented to estimate the deterministic error such as bias, scale factor, and non-orthogonality. Allan variance method is used to characterize the stochastic noise in inertial sensor. Experimental results are afforded and evaluated.

The focal lengths of the sub-eyes in a single-layer uniform curved compound eye are all the same, resulting in poor imaging quality for the compound eye. A non-uniform curved compound eye can effectively solve the problem of poor edge-imaging quality, however, it suffers from a large spherical aberration, and is unable to achieve zoom imaging. To solve these problems, a new type of aspherical artificial compound eye structure with variable focal length is proposed in this paper. The structure divides the surface compound eye into three fan-shaped areas with different focal lengths of the microlens in different areas, which allow the artificial compound eye to zoom in a certain range. The focal length and size of the microlens is determined by the area and the location of the microlens. The aspherical optimization of the microlens is calculated, and spherical aberration in each area is reduced to one percent of the initial value. Through simulation analysis, the designed artificial compound eye structure realizes focal length adjustment and effectively reduces the problem of the poor imaging quality of the curved compound eye edge. As a result, an aspherical artificial compound eye sample—where the number of sub-eyes is n = 61, and the diameter of the base is Φ = 8.66 mm—was prepared by using a molding method. Additionally, the mutual relationship between the eyes of the child was calibrated, and hence, a mathematical model for the simultaneous identification of multiple sub-eyes was established. This study set up an experimental artificial compound eye positioning system, and through a number of microlens capture target point settlement coordinates, achieved an error value of less than 10%.

Compared with the conventional compound eye processing method, a new fabrication method—namely, a mold casting method—was presented. This method is simple, low-cost, easy to implement, and can be reused. A bionic compound eye array model with 61 ommatidia arranged inhomogeneously onto a curved surface was fabricated. The curved surface had a radius of 9 mm and a thickness of 0.5 mm. The margin imaging quality was improved significantly by the analysis of light beam focus and the optical imaging properties of the fabricated compound eye. The sub-image of each ommatidium had a high resolution. There was 5% error between the collecting spot brightness and simulation analysis results, which proved that the production method is feasible.