Is there any free Virtual Reality Tracking sdk or tutorial? such as deepmotion

is there any free Virtual Reality Tracking sdk or tutorial?
found this one , but not free.
https://www.deepmotion.com/virtual-reality-tracking
https://blog.deepmotion.com/2018/04/30/how-to-make-3-point-tracked-full-body-avatars-in-vr/

is full body IK such as Power IK & poseable mesh which used to track head and hands a solution?

thanks!