I have looked around and found very little about this concept. Basicly it's a vertical column mounted to the floor and wall with thrust bearings. There would be linear rail attached vertically to the column with a horizontal arm coming off. The column would be rotated in combination with moving the carriage in and out on the horizontal beam to achieve x and y movement. The whole horizontal arm will be raised and lowered for z travel. Have any of you seen anything like this. What do you think of it?