Position</h2><p>
<p>The position of the CG of the tractor relative to the origin \({\rm O}\) is</p>
<p>
\begin{equation*} {\bf p}_{{\rm T}/{\rm O}} = x \, {\bf i} + y \, {\bf j}. \end{equation*}
</p>
<p>Relative positions are</p>
<p>
\begin{eqnarray}
\nonumber {\bf p}_{{\rm F}/{\rm T}} &=& a \cos \psi {\bf i} + a \sin \psi {\bf j}. \\
\nonumber {\bf p}_{{\rm R}/{\rm T}} &=& - b \cos \psi {\bf i} - b \sin \psi {\bf j}. \\
\end{eqnarray}
</p>
<p>Position of axles</p>
<p>
\begin{eqnarray}
\nonumber {\bf p}_{{\