Source code for ossdbs.electrodes.microelectrode

# Copyright 2023, 2024 Jan Philipp Payonk, Julius Zimmermann
# SPDX-License-Identifier: GPL-3.0-or-later

from dataclasses import dataclass

import netgen
import netgen.occ as occ
import numpy as np

from .electrode_model_template import ElectrodeModel
from .utilities import get_highest_edge, get_lowest_edge


@dataclass
class MicroElectrodeParameters:
    """Electrode geometry parameters."""

    # dimensions [mm]
    tip_length: float
    tip_diameter: float
    contact_length: float
    lead_diameter: float
    total_length: float

    def get_center_first_contact(self) -> float:
        """Returns distance between electrode tip and center of first contact."""
        return 0.5 * self.tip_length

    def get_distance_l1_l4(self) -> float:
        """Returns distance between first level contact and fourth level contact."""
        return -1.0


[docs]class MicroElectrodeModel(ElectrodeModel): """MicroElectrode. Attributes ---------- parameters : MicroElectrodeParameters Parameters for MicroElectrode geometry. rotation : float Rotation angle in degree of electrode. direction : tuple Direction vector (x,y,z) of electrode. position : tuple Position vector (x,y,z) of electrode tip. """ _n_contacts = 1 def _construct_encapsulation_geometry( self, thickness: float ) -> netgen.libngpy._NgOCC.TopoDS_Shape: """Generate geometry of encapsulation layer around electrode. Parameters ---------- thickness : float Thickness of encapsulation layer. Returns ------- netgen.libngpy._NgOCC.TopoDS_Shape """ center = tuple(np.array(self._direction) * self._parameters.tip_length * 0.5) radius = self._parameters.tip_length + thickness height = self._parameters.total_length - self._parameters.tip_length * 0.5 tip = occ.Sphere(c=center, r=radius) lead = occ.Cylinder(p=center, d=self._direction, r=radius, h=height) encapsulation = tip + lead encapsulation.bc("EncapsulationLayerSurface") encapsulation.mat("EncapsulationLayer") return encapsulation.Move(v=self._position) - self.geometry def _construct_geometry(self) -> netgen.libngpy._NgOCC.TopoDS_Shape: contact = self._contacts() electrode = netgen.occ.Glue([self.__body(), contact]) return electrode.Move(v=self._position) def __body(self) -> netgen.libngpy._NgOCC.TopoDS_Shape: radius_lead = self._parameters.lead_diameter * 0.5 center = tuple(np.array(self._direction) * self._parameters.tip_length) height_lead = self._parameters.total_length - self._parameters.tip_length lead = occ.Cylinder(p=center, d=self._direction, r=radius_lead, h=height_lead) lead.bc(self._boundaries["Body"]) return lead def _contacts(self) -> netgen.libngpy._NgOCC.TopoDS_Shape: origin = (0, 0, 0) direction = (0, 0, 1) radius = self._parameters.tip_diameter * 0.5 height = self._parameters.contact_length contact = occ.Cylinder(p=origin, d=direction, r=radius, h=height) contact.bc(self._boundaries["Contact_1"]) min_edge = get_lowest_edge(contact) max_edge = get_highest_edge(contact) min_edge.name = "Contact_1" contact = contact.MakeFillet(contact.edges["Contact_1"], 0.05) max_edge.name = "Contact_1" for face in contact.faces: face.name = "Contact_1" if np.allclose(self._direction, direction): return contact # rotate electrode to match orientation # e.g. from z-axis to y-axis rotation = tuple( np.cross(direction, self._direction) / np.linalg.norm(np.cross(direction, self._direction)) ) angle = np.degrees(np.arccos(self._direction[2])) return contact.Rotate(occ.Axis(p=origin, d=rotation), angle)