Re: Reply to Ben Ocko re: pseudomotors

[Mark Rivers <RIVERS@cars3.uchicago.edu>]

Gerry wrote:
> I don't understand what these 'geometry fields' are for.  Do I need to?

What I mean is a place to store geometric constants or variables for the
pseudomotor device.  For example on a lift table the distances between the
pivot points are needed in order to have a 'tilt' pseudomotor work in absolute
units of degrees or mrad.  For a lift table there might be half a dozen such
geometric constants.  The lift table will probably have 3 to 6 pseudomotors
(X, Y, Z, AX, AY, AZ).  If each pseudomotor has 4 fields where geometry
information can be stored that is more than enough.  It is up to the person
who implements the code for the lift table to define, for example, that the
distance from the Y1 jack to the line between the Y2 and Y3 jacks is stored in
the G1 field of the Y pseudomotor, etc.

Mark