In the summer of 2006 I accompanied Dr. Akihiko Kumagai (CSU Sacramento) to work at the Contact Dynamics Simulation Laboratory (CDSL) at NASA Marshall Space Flight Center (MSFC). While there we worked on a close-form solution to the forward kinematics of the CDSLs 6-DOF CDSL Stewart platform. Our project was a matlab implementation of the algebraic method of solving the forward kinematics described in the following paper:

Forward kinematics of the general 6-6 Stewart platform using algebraic elimination.
Authors: Tae-Young Lee, Jae-Kyung Shim
Department of Mechanical Engineering, Korea University, 5-Ka Anam-Dong Sungbuk-Ku, Seoul, 136-701, South Korea.
36th issue of Mechanism and Machine Theory magazine (2001, 1073-1085).

https://www.youtube.com/watch?v=ABYmeZRDyYg

The matlab code is in the /src directory.

I wrote this code in the summer of 2006. It is provided here, for reference, but I offer no support or advice.