Wheelchair-Mounted　Robotic　Arm　(WMRA)　is　a　typical　assistive　robot　system　for　the　elder/　disabled　people.This　paper　studies　the　motion　mapping　from　a　human　master　arm　to　a　heterogeneous　slave　WMRA　for　manipulation　in　activity　of　daily　livings.The　motion　of　the　human　master　arm　is　measured　via　a　wearable　motion　capture　system,　and　then　the　motion　captured　data　is　transformed　into　the　joint　space　of　the　heterogeneous　slave　robot　arm　using　a　corresponding　joint-set　motion　mapping　algorithm,　and　an　autonomous　obstacle　avoidance　algorithm　is　also　developed,　as　a　result,　the　motion　of　the　heterogeneous　slave　WMRA　can　be　easily　controlled　by　the　user　via　the　motion　of　his/her　arm.This　method　possesses　two　remarkable　advantages　that　are　vital　to　the　application　of　the　WMRA　systems:　the　elder/disabled　user　can　operate　the　WMRA　system　intuitively　and　conveniently,　and　the　fatigue　degree　and　error　rate　of　the　user　can　be　significantly　reduced;　the　safety　of　WMRA　in　an　unstructured　and　constrained　home　environment　can　be　significantly　improved.　©　2018,　Chinese　Institute　of　Electronics.　All　right　reserved.