Heterogeneous　master-slave　robots　are　widely　used　as　both　assistive　robot　system　for　the　elder/disabled　people　and　teleoperation　robot　system　for　dangerous　environments,　and　in　these　applications　the　orientation　of　the　links　of　the　slave　robot　is　critical　for　the　convenient　and　intuitive　teleoperation.　This　paper　studies　the　motion　mapping　from　a　human　master　arm　to　a　heterogeneous　slave　robot　arm　UR5　for　tele-manipulation　using　unit　dual　quaternions　(UDQ).　Firstly,　we　analogy　the　links　of　the　slave　robot　to　the　links　of　the　human　master　arm,　and　accordingly　group　the　slave　arm　joints　into　＇shoulder＇,　＇elbow＇　and　＇wrist＇　joint　set;　Then,　we　capture　the　motion　(orientations)　of　the　human　master　arm　via　a　wearable　motion　capture　system;　Finally,　we　compute　the　motion　of　the　corresponding　joint-set　of　the　heterogeneous　slave　robotic　arm　via　UDQ　based　inverse　kinematics.　As　a　result,　the　operator　can　tele-operate　the　heterogeneous　robot　system　intuitively　and　conveniently,　and　the　fatigue　degree　and　error　rate　of　the　user　can　be　significantly　reduced,　and　thus　the　safety　of　teleoperation　in　an　unstructured　and　constrained　environment　can　be　significantly　improved.　©　2017　IEEE.