Sample¶
The MD3 microdiffractometer goniometer, the sample environment, and the ISARA robot. PVs / interfaces verified against mx3_beamline_library/devices/{motors,cryo}.py and classes/motors.py.
MX3 holds a cryocooled crystal on the MD3 microdiffractometer and rotates it through an oscillation; the sample side is the goniometer, its cooling and viewing, and the robot that loads it.
| Asset | Family | PV / interface | What it does |
|---|---|---|---|
Goniometer |
Goniometer | MXCuBE Exporter (no PV) | orients the crystal (omega / kappa / phi) |
SampleTemperature |
TemperatureController | MX3CRYOJET01: |
cryojet sample cooling |
Backlight |
Backlight (loose) | MD3 Exporter (no PV) | sample backlight for centring |
BeamStop |
BeamStop | MD3 Exporter (no PV) | blocks the direct beam at the sample |
The MD3 goniometer¶
The Goniometer is the MD3 (Arinax) microdiffractometer: omega rotation plus a mini-kappa (kappa / phi), sample centring (CentringX / Y), and alignment (AlignmentX / Y / Z). It reuses the graduated Goniometer family, the same one Diamond I03 earned from its Smargon (MX3's MD3 is a richer instance, kappa plus alignment). The discriminator the family carries, a multi-axis crystal-orientation goniometer, fits exactly.
What is new is not the family but the control interface: the MD3 is driven over the MXCuBE Exporter protocol (a custom TCP framing), not EPICS, so it carries no PV; each axis is an Exporter property name (Omega, CentringX, ...) resolved at runtime against the MD3 host. CORA models it as a Goniometer Asset and treats the Exporter as a ControlPort adapter; the concrete host is deployment config (GONIO-1). The MD3 also carries the Backlight and BeamStop as Exporter sub-devices.
Sample environment¶
The SampleTemperature cryojet reuses the TemperatureController family (graduated in #350), keeping the crystal at cryogenic temperature through the dataset.
The ISARA robot¶
MX3's throughput comes from the ISARA sample-mounting robot, which loads pins from a dewar onto the goniometer between datasets, its mount / unmount trajectories gated on the MD3 state. It is not modelled as a device here: CORA models autonomous sample exchange as a Procedure over the spine, threaded through the Subject aggregate so each crystal's identity and provenance is tracked and gated by a Clearance, the same shape as the Diamond i03 and i24 loops (ROBOT-1). The robot's TCP interface is named, but the Procedure is deferred at this design phase.