First of all, I'm quite new to modelling and animation but already watched tons of tutorials
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On the other hand, if I don't rotate(+15 , 0, -15) robot's hip(root_joint) on y axis, problem disappears. That move gives more realistic walking to robot so I want to keep it. I checked root joint and control curve pivots so they are aligned perfectly on Y axis.
I also tried to enable "Root Transform Position (XZ)" in Unity but in that case robot doesn't move forward.
Here is a small video of problem : https://youtu.be/QYeCUVX28l4
I'm not sure if anybody experienced such problem before but I'll be highly appreciated if we can come up with a solution.
Looking forward to hear you guys.