SurfaceElectrodeArray#

class SurfaceElectrodeArray( num_rows: int, num_cols: int, inter_electrode_distance__mm: Quantity__mm, electrode_radius__mm: Quantity__mm, center_point__mm_deg: tuple[Quantity__mm, Quantity__deg] = (0.0 * pq.mm, 0.0 * pq.deg), bending_radius__mm: Quantity__mm = 0.0 * pq.mm, rotation_angle__deg: Quantity__deg = 0.0 * pq.deg, differentiation_mode: Literal['monopolar', 'bipolar_longitudinal', 'bipolar_transversal', 'laplacian'] = 'monopolar', )[source]#

Bases: object

Surface electrode array for EMG recording.

Represents a grid of surface electrodes with configurable spacing, size, and differentiation modes.

Parameters:

num_rows (int) – Number of rows in the electrode array
num_cols (int) – Number of columns in the electrode array
inter_electrode_distance__mm (float) – Inter-electrode distance in mm.
electrode_radius__mm (float, optional) – Radius of the electrodes in mm
center_point__mm_deg (tuple[float, float]) – Position along z in mm and rotation around the muscle theta in degrees.
bending_radius__mm (float, optional) – Bending radius around which the electrode grid is bent. Usually this is equal to the radius of the muscle.
rotation_angle__deg (float, optional) – Rotation angle of the electrodes in degrees. This is the angle between the electrode grid and the muscle surface.
differentiation_mode ({"monopolar", "bipolar_longitudinal", "bipolar_transversal", "laplacian"}) – Differentiation mode. Default is monopolar.

pos_z#

Longitudinal electrode positions in mm, shape (num_rows, num_cols). Available after class initialization via _create_electrode_grid().

Type:: np.ndarray

pos_theta#

Angular electrode positions in radians, shape (num_rows, num_cols). Available after class initialization via _create_electrode_grid().

Type:: np.ndarray

electrode_positions#

Complete electrode position arrays (pos_z, pos_theta). Available after class initialization via _create_electrode_grid().

Type:: tuple[np.ndarray, np.ndarray]

num_electrodes#

Total number of electrodes (num_rows * num_cols).

Type:: int

num_channels#

Number of recording channels based on differentiation mode.

Type:: int

Methods

`__init__`
`get_H_sf`	Get the spatial filter for the electrode array.

Attributes

`electrode_positions`	Complete electrode position arrays (z, theta) in physical coordinates.
`num_channels`	Number of recording channels based on differentiation mode.
`pos_theta`	Angular positions of electrodes in radians.
`pos_z`	Longitudinal positions of electrodes in mm.

property pos_z: Quantity__mm#

Longitudinal positions of electrodes in mm.

Returns:: Array of shape (num_rows, num_cols) containing z-coordinates of each electrode position in mm.
Return type:: Quantity__mm
Raises:: AttributeError – If electrode grid has not been created. Run constructor first.

property pos_theta: Quantity__rad#

Angular positions of electrodes in radians.

Returns:: Array of shape (num_rows, num_cols) containing angular coordinates of each electrode position in radians.
Return type:: Quantity__rad
Raises:: AttributeError – If electrode grid has not been created. Run constructor first.

property electrode_positions: tuple[Quantity__mm, Quantity__rad]#

Complete electrode position arrays (z, theta) in physical coordinates.

Returns:: Tuple containing: - pos_z: Longitudinal positions in mm, shape (num_rows, num_cols) - pos_theta: Angular positions in radians, shape (num_rows, num_cols)
Return type:: tuple[Quantity__mm, Quantity__rad]
Raises:: AttributeError – If electrode grid has not been created. Run constructor first.

property num_channels: int#

Number of recording channels based on differentiation mode.

Returns:: Number of recording channels. Depends on differentiation_mode: - "monopolar": num_rows * num_cols - "bipolar_longitudinal": (num_rows - 1) * num_cols - "bipolar_transversal": num_rows * (num_cols - 1) - "laplacian": (num_rows - 2) * (num_cols - 2)
Return type:: int
Raises:: AttributeError – If channel count has not been calculated. Run constructor first.

get_H_sf( ktheta_mesh_kzktheta: ndarray, kz_mesh_kzktheta: ndarray, ) → ndarray | float[source]#

Get the spatial filter for the electrode array.

Parameters:

ktheta_mesh_kzktheta (np.ndarray) – Angular spatial frequency mesh
kz_mesh_kzktheta (np.ndarray) – Longitudinal spatial frequency mesh

Returns:

H_sf – Spatial filter for the specified differentiation mode

Return type:

np.ndarray or float