[Stonius (Markus)]

Hi there,

I notice there is a lot of talk about removing tangential error in these mounts by mechanical means, using curved rods or type 4 systems with 3 arms, etc.

My understanding is that the accuracy required in manufacturing is the undoing of the gains they provide. EG, the curved rod system requires a gear with the attendant PE and backlash, and aparrently the three arm system requires manufacturing tolerances smaller than a CNC can provide according to one site that studied the tolerances and resultant errors from that design.

The simplest design is a motor that drives a straight rod with a bendy connector, surely? I know that people have done straight rods with mathematical compensation for the Tan error, but has anyone then done an analysis of the inevitable tracking error in something like PhD? If there is a constant repeatable error, then surely the curve can be used to compensate for the error (again in software)?

Is anyone doing this?

Best

Markus