[AMR] Kinematics defs, better linking

electives/amr/parts/01_kinematics/01_forward.tex

@@ -8,5 +8,8 @@ $ \begin{bmatrix}
         L_1 \sin(\theta_1) + L_2 \sin(\theta_1 + \theta_2)
     \end{bmatrix}$\\
 }
-With workspace (pos) $W$ for $\theta_1, \theta_2 \in [-\pi, \pi]$
-% TODO: Example? (w02s42 possibly)
+Similar for $n$R sys (more angles). Wspc $W$ $\theta_1, \theta_2 \in [-\pi, \pi]$.
+Last dim may be sum of angles. Jacobian: see \ref{sec:ms-lin}
+
+\shortdefinition[Singularity] Loss of deg of Freed. $\det(\mat{J}(\vec{\theta})) = 0$
+% TODO: Determinant computation