Update users_comments.md

Author: AtsushiSakai

users_comments.md

@@ -363,6 +363,12 @@ Dear AtsushiSakai, thank you so much for this material, it's so useful to me, i'
 
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+Dear Atsushi Thanks for compiling such a vast resource for robotics motion planning.
+
+--Kartik Prakash
+
+---
+
 
 # Citations