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Controls

The shutters, the motion controllers, and the seam between CORA and the floor, which at MX3 is a heterogeneous control plane.

Shutters and triggering

The WhiteBeamShutter (MX3FE01SHT01) and MonoBeamShutter (MX3BLSH01SHT01) are PSS photon shutters gating the beam into the hutch; an MD3 fast shutter (Exporter-driven) gates the per-oscillation exposure at the sample. The rotation collection is the goniometer omega sweep synchronized with the Eiger frames; the concrete trigger wiring is part of the recipe layer (deferred at this design phase).

Motion controllers

The endstation and detector stages run on Australian Synchrotron Power Brick (PMAC) motion controllers (the MX3STG..MOT.. axis records, class ASBrickMotor); their firmware and IPs are not in the library (DRIVE-1), so EndstationMotionController is carried as a MotionController family with the specifics blank.

The seam: CORA and a heterogeneous floor

MX3 is where CORA's ControlPort meets its most varied floor yet. Where the other deployments are single-control-plane (EPICS over Channel Access, via ophyd), MX3 is four planes at once, and the seam is the same in shape but wider in span.

CORA owns (its conducting engine, over the ControlPort):

  • the rotation-MX collection: setting the energy, positioning the detector distance, orienting the crystal on the goniometer, and arming and triggering the detector through the oscillation;
  • the autonomous sample-exchange loop (the ISARA robot) as a Procedure, and the choice of what to collect, gated by the trust boundary.

CORA drives through (the floor it actuates and observes, and does not replace), now across four transports:

  • EPICS (via ophyd) for the monochromator, attenuator, shutters, cryojet, flux and beam-position monitors, OAV camera, and the Power Brick stages, the ControlPort boundary CORA already knows.
  • the MXCuBE Exporter protocol (TCP) for the MD3 microdiffractometer goniometer and its sub-devices; CORA treats the Exporter client as a ControlPort adapter.
  • the SIMPLON REST API (HTTP) for the DECTRIS Eiger; the arm / trigger / disarm / config lifecycle is a ControlPort adapter over REST, the first non-EPICS detector in the fleet.
  • the ISARA TCP client for the sample robot, driven by the sample-exchange Procedure.

The point for CORA is that the ControlPort abstraction holds: the same conducting engine drives MX3 over four transports without a new domain model, only new adapters. Data egress (the Eiger frames) moves over the TransferPort into CORA's Dataset of record, and any reduction (indexing / integration) is ComputePort work.

The software interfaces (DECTRIS-SIMPLON, MD3-Exporter, ISARA-robot, BlackFly, the MD3 Redis camera) are referenced by interface only, never registered as Assets.