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The A-r-Star (Ar) Pathfinder

International Journal of Computer Applications
© 2013 by IJCA Journal
Volume 67 - Number 8
Year of Publication: 2013
Daniel Opoku
Abdollah Homaifar
Edward Tunstel

Daniel Opoku, Abdollah Homaifar and Edward Tunstel. Article: The A-r-Star (Ar) Pathfinder. International Journal of Computer Applications 67(8):32-44, April 2013. Full text available. BibTeX

	author = {Daniel Opoku and Abdollah Homaifar and Edward Tunstel},
	title = {Article: The A-r-Star (Ar) Pathfinder},
	journal = {International Journal of Computer Applications},
	year = {2013},
	volume = {67},
	number = {8},
	pages = {32-44},
	month = {April},
	note = {Full text available}


This paper presents a variant of the A-Star (A^*) pathfinder for robot path planning calledA_r^* (pronounced A-r-Star)and demonstrates that the A_r^*algorithm outperforms A^* in a uniformly gridded sparse world and gives performance matching that of A^* in a uniformly gridded cluttered world. This algorithm is simple to implement and understand. It alsohighlights the performance advantages of theA_r^*algorithm and proves its properties experimentally and analytically (where appropriate). Some challenges affecting the performance of A_r^*have been presented and some solutions to these challenges have been developed and implemented. The performance of A_r^*has been compared toA^*running on both uniform and multi-resolution grids of different world scenarios. Results show that on a sparse high-resolution uniform grid worldA_r^*'s search speed scales well and it outperforms A^* by an exponential factor.


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