LINE DETECTION FOR AGRICULTURAL VISION-GUIDANCE USINGOBJECT-ORIENTED SOFTWARE FRAMEWORK WITH FLEXIBLEBASE ARCHITECTURE
Biomass Control Systems Engineering, Biomass Conversion
Vazquez-Arellano ManuelIntroduction
Decreasing computer costs and increased use of electrical and electronic systems haveallowed a rapid increase in the development of autonomous and automatic vehicles inagriculture. Machine vision is the most appealing method to find guidance lines such as paths,
crop rows and aligned trees for vehicle control because it follows human practice taking
guidance from scenes. Until now, many successful researches have been done to detect lines
for vision guidance systems; however, they have a limitation: the line detection vision system
is only useful for a specific target. The objective of this research was to develop an objectoriented software framework with flexible base architecture and an algorithm library that
contains many typical image processing techniques used in the software framework. The
software framework should provide an effective way for developing line detection
applications for any programmer (novice or advanced). Also, the software framework shoulddemonstrate it's capability of developing concrete vision system for several targets, forinstance: crop rows, agricultural paths, aligned trees, etc.
MethodConsidering that there are already several researches about line detection for machine vision,
it would be desirable to integrate all the vision systems into a versatile one. It was noticed that
all the different processes have a common pattern that consists of two steps: simplificationand line search. Simplification step converts a original image (containing big amount ofinformation) into a much simpler simplified image (containing small amount of information)and line search step finds the guidance line from the simplified image. After integrating thecommon parts of the different processes an abstract process of line detection was defined, thisabstract process has the flexible base architecture. The software framework is theimplementation of the flexible base architecture where several algorithms can be injected into
the simplification series and line search place folders for the creation of particular target
vision system. An algorithm library with typical image processing techniques is available fordevelopers, who can write very simple code for just injecting those algorithms into thesoftware framework.
Results and Discussion
In this research -for demonstration- paths and crop rows detection systems were created using
different methods. It was demonstrated the simplicity of changing from one method to anotherby just replacing the concrete algorithm components from the library. The root mean square(RMS) value was used as the index for evaluating the accuracy of line detection; the best
method was the one with the smallest RMS value. Other targets like trees, wheel tracks,
harvested rice boundaries and rice fields could also be detected using the framework andalgorithm library.
Conclusion
A software framework for line detection with flexible base architecture and an algorithm
library with the typical image processing techniques were successfully developed. Injecting
the concrete algorithms into the software framework allowed the creation of particular visionsystem for detecting lines in specific situations.