1. The problem statement, all variables and given/known data equations above are descriptive of a system with two configuration variables, q1 and q2. inputs are tau1 and tau2. d and c values are given. the question is about conversion of above equations to a state-space equation where the state-variables are x1 = q1_dot, x2 = q1_2dot, x3 = q2_dot, x4 = q2_2dot. 2. Relevant equations 3. The attempt at a solution Since variables q1 and q2 are coupled in the equations of motion, so I haven't been able to come up with a way to decouple them and makes a state-state equation. Any insights on this would very much be appreciated.