Parallel link machine design

A machine as claimed in any of the preceding claims wherein said bifurcated common nodes each comprise two hemispheres, one for each strut passing through the respective machine node, the two hemispheres being spherically arranged with respect to each other so as to be pivotable relative to each other about a common axis, and the spherical arrangement being retained in a complementary socket providing for multi-axis movement thereof.

A machine comprising elongate struts that can be driven through machine nodes to vary the effective strut length, three of said struts being movably connected together at one end so as to define a first tool support movable in space in dependence upon the lengths of said three struts, and a further two of said struts being movably connected together at one end to define a second tool support movable in space in dependence upon the lengths of said two struts, and a tool supported between said first and second tool supports.

A machine comprising three adjustable length struts spaced apart and journalled for multidirectional pivotal movement relative to a machine sub-frame at one end and movably connected together at their other ends so as to define a first tool support movable in free space in dependence upon the relative lengths of the three struts, and wherein a second tool support movable in free space is defined by the movably connected ends of two further adjustable length struts which at their other ends are spaced apart and journalled for multi-directional pivotal movement relative to said sub-frame.

A friction drive motor for effecting relative longitudinal movement between the motor and an elongate member, said friction drive motor comprising opposite pairs of driven rollers frictionally engaging opposite sides of the elongate member, said opposed pairs of driven rollers being coupled to larger diameter wheels which frictionally engage with each other across the width of said elongate member.