In robot path planning, the robot digital roadmap recognition is very important. The image preprocessing can affect the
recognition result. Image enhancement is always used in image preprocessing to provide better input for the following
automated image processing and fuzzy image enhancement is one of a effective approach that be used widely in image
preprocessing. Through the research of the Pal fuzzy enhancement algorithm, there were two main bugs of the algorithm.
The first one was the definition of the membership function, and the second was the selection of the transition point. In
this paper, a novel improved algorithm is proposed by analyzing the deficiencies of Pal algorithm. First, use the 2D
OTSU operator to automatically select the best threshold value, solve the disadvantage that the transition point should be
set artificially, and eliminate the random selection. Then, in order to improve the image information loss problem,
modify the core membership function of the fuzzy enhancement algorithm. Finally, the new algorithm was applied to
process digital roadmap for Pioneer III robot. The experimental results indicate that the proposed image enhancement
method can achieve better performance, and have higher processing speed than now-available fuzzy image enhancement
algorithms. And it also possesses the property of high practicability and generality.