When drift-scan CCD shooting the sky where bright stars are in the filed of view, because of the frame transfer feature, the trailing smear will appear throughout the star image. A fast smear trailing elimination algorithm was proposed by analyzing the imaging mechanism. The method firstly decreased the background non-uniformity by fitting the background, then located smear trailing by calculating the mean gray value of every column in star image and comparing the mean gray values before and after fitting, finally eliminated smear trailing by setting the trailing pixel with the mean gray value after fitting. The experimental results show that the smear trailing is removed completely and the mean deviation of background is apparently reduced, moreover the consuming time of this method is only 20% of that of traditional smear elimination method, which proves the validity of the method.

A classification method based on trinocular stereovision, which consisted of geometrical classifier and color classifier, was proposed to autonomously guide vehicles on unstructured terrain. In this method, rich 3D data which were taken by stereovision system included range and color information of the surrounding environment. Then the geometrical classifier was used to detect the broad class of ground according to the collected data, and the color classifier was adopted to label ground subclasses with different colors. During the classifying stage, the new classification data needed to be updated continuously to make the vehicle adapt to variable surrounding environment. Two broad categories of terrain what vehicles can drive and can not drive were marked with different colors by using the classification method. The experimental results show that the classification method can make an accurate classification of the terrain taken by trinocular stereovision system.

To improve the efficiency of Advanced Encryption Standard （AES） algorithm on ARM processor, aiming at AES algorithm with 128-bit block length and key length, an optimization method was proposed. The method can speed up execution efficiently on ARM processor while consuming less ROM memory. A theoretical analysis of the Rijndael algorithm and of the proposed optimization was discussed. S box was generated by real-time calculation. The MixColumns and InvMixColumns transformations were amended to execute efficiently on 32-bit processor. On-the-fly key expansion was adapted. Simulation results of the optimized algorithm on S3C2440 processor were presented. The experimental results show that the optimization of AES algorithm can execute efficiently on S3C2440 and consume less ROM memory. The method can be applied to embedded systems with memory constraints.