Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Paper format. National Exams, December 2018 — 16-Mec-B12 Robotics. Closed book, three hours, one 8.5″×11″ two-sided formula sheet and an approved Casio or Sharp calculator permitted. Seven questions, each of equal value (20 marks); the rubric states that five questions constitute a complete paper and that only the first five in the answer book are marked. As a study resource all seven are solved here. Marks shown in parentheses are the printed sub-part values.
Notation. The paper's own nomenclature is used throughout: $\hat{X}_A,\hat{Y}_A,\hat{Z}_A$ are the unit vectors of frame $\{A\}$; a leading superscript as in ${}^{A}V$ names the frame the vector is referenced to; and ${}^{B}_{A}T$ is the transform of frame $\{A\}$ expressed relative to $\{B\}$. This is Craig's convention, so Craig's modified (distal) Denavit–Hartenberg parameters are used for the link tables.
Reference texts.