pyaml.bpm.bpm#

Beam-position monitor elements and their runtime interfaces.

Classes

BPM(name[, lattice_names, description, ...])

Beam position monitor (BPM) element.

class pyaml.bpm.bpm.BPM(name, lattice_names=None, description=None, x_pos=None, y_pos=None, x_offset=None, y_offset=None, tilt=None)#

Bases: Element, DynamicValidation

Beam position monitor (BPM) element.

Represents a BPM in the accelerator lattice and provides access to its associated readback signals, including horizontal and vertical beam positions, calibration offsets, and mechanical tilt.

Parameters:

name (str) – Name of the BPM.
lattice_names (str | None, optional) – Lattice-specific name or names identifying the BPM.
description (str | None, optional) – Description of the BPM.
x_pos (str | None, optional) – Device catalog key for the horizontal beam position.
y_pos (str | None, optional) – Device catalog key for the vertical beam position.
x_offset (str | None, optional) – Device catalog key for the horizontal BPM offset.
y_offset (str | None, optional) – Device catalog key for the vertical BPM offset.
tilt (str | None, optional) – Device catalog key for the BPM tilt.

Attributes

`positions`	Read accessor for the horizontal and vertical beam positions, in metres.
`offset`	Read/write accessor for the two calibration offsets, in metres.
`tilt`	Read/write accessor for the mechanical tilt, in radians.

Methods

`attach()`	Attach BPM attributes to a peer.
`get_pos_devices()`	Return configured device keys used for position readback.
`get_tilt_device()`	Return the configured device key used for tilt access.
`get_offset_devices()`	Return configured device keys used for offset control.

Configuration

- type: pyaml.bpm.bpm
  name: BPM_NAME
  lattice_names: LATTICE_BPM_NAME
  x_pos: DEVICE/X_POSITION
  y_pos: DEVICE/Y_POSITION
  x_offset: DEVICE/X_OFFSET
  y_offset: DEVICE/Y_OFFSET
  tilt: DEVICE/TILT

attach(peer, positions, offset, tilt)#

Attach BPM attributes to a peer.

Parameters:

peer (object) – Simulator or control-system peer.
positions (RBpmArray) – Read-only horizontal and vertical position interface.
offset (RWBpmOffsetArray) – Read/write horizontal and vertical offset interface.
tilt (RWBpmTiltScalar) – Read/write tilt interface.

Returns:

Self – Shallow copy of this BPM bound to peer and its interfaces.

Return type:

Self

get_offset_devices()#

Return configured device keys used for offset control.

Returns:: list of str or None – Horizontal and vertical offset device keys.
Return type:: list[str | None]

get_pos_devices()#

Return configured device keys used for position readback.

Returns:: list of str or None – Horizontal and vertical position device keys.
Return type:: list[str | None]

get_tilt_device()#

Return the configured device key used for tilt access.

Returns:: str or None – Tilt device key.
Return type:: str | None

property offset: ReadWriteFloatArray#

Get the BPM offset values.

Returns:: ReadWriteFloatArray – Read/write array containing horizontal and vertical offsets.
Raises:: PyAMLException – If offset has not been attached

property positions: ReadFloatArray#

Get the BPM position readings.

Returns:: ReadFloatArray – Read-only array containing horizontal and vertical positions.
Raises:: PyAMLException – If positions have not been attached

property tilt: ReadWriteFloatScalar#

Get the BPM tilt angle.

Returns:: ReadWriteFloatScalar – Read/write BPM tilt angle used for rotation correction.
Raises:: PyAMLException – If tilt has not been attached