# POLDI motors

## Physical Motors

D1HL
  2-axis diaphragm - horizontal translation (left)
D1HR
  2-axis diaphragm - horizontal translation (right)
D2HL
  4-axis diaphragma - horizontal translation (left)
D2HR
  4-axis diaphragma - horizontal translation (right)
D2VU
  4-axis diaphragma - vertical translation (upper side)
D2VL
  4-axis diaphragma - vertical translation (lower side)
SHU
  sample table x-translation
SHL
  sample table y-translation
SV
  sample table z-translation
SA
  sample table rotation
SGU
  sample goniometer rotation (alpha)
SGL
  sample goniometer rotation (beta)
RSU
  sample table overlay for radioactive samples (x-translation)
RSL
  sample table overlay for radioactive samples (y-translation)
RSA
  sample table overlay for radioactive samples (rotation)

## Virtual motors

Virtual motors are instrument parameters which can be driven with the drive and run commands, though they are not physical motors. Mostly this encompasses coordinated movements of motors around several axis or other lengthy and error prone hardware operations.

flightpathlength
  distance between chopper and detector [in mm]
chopper_sample
  distance between chopper and sample [in mm]
chopper_dia
  distance between chopper and 2-axis diaphragma [in mm]
dia1_dia2
  distance between 2-axis diaphragma and 4-axis diaphragma [in mm]
dia2_sample
  distance between 4-axis diaphragma and sample position [in mm]
detectordist
  distance between sample position and detector [in mm]
chopperspeed
  disk chopper speed
twotheta
  scattering angle to the middle of the detector
x0_det
  centre of the detector circle (x-coordinate)
y0_det
  centre of the detector circle (y-coordinate)
nodet
  number of detector cells (400 really cells exist)
det_size
  size of a single detector cell [in mm]
det400
  automatic configuration of the histogram memory to 400 detectors with a cell size of 2.5 mm
det800
  automatic configuration of the histogram memory to 800 detectors (including 400 virtual detectors) with a cell size of 1.25 mm

Note: The adjustments of det400 and det800 will be activated after giving a HM init command!