| 摘要 |
A handheld pointer-member, freely moveable within an orthogonally referenced three-dimensional workspace. Six rotational encoder assemblies, electronically couples to a host computer, are axed in pairs to form a triangle. Six tensioned cables are guided through six holes near each of the six rotational encoder assemblies. Each cable contacts an encoder's rotateable input shaft, thereby digitizing all changes in the cable's extended length into the host computer. One cable from each vertex of the triangle is affixed to one of two cable attachment points spaced apart on the pointer-member. The host computer continuously trilaterates the XYZ locations of both cable attachment-points using measured changes in the six cable lengths. The pitch and yaw attitude between the two cable attachment points is derived and used to compute the locations of the tips of the pointer-member. The user guides the pointer-member's tips over an object's surface, thereby digitizing its shape into the host computer.
|
