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reworked cage_func to use class for axes

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This commit is contained in:
Martin Zietz
2021-01-21 15:05:44 +01:00
parent b1f55b4dc4
commit 9620bcdfdd
7 changed files with 115 additions and 92 deletions
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cage_func.py
+83 -47
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@@ -1,15 +1,81 @@
from pyps2000b import PS2000B
import globals as g
import settings as g
import pandas
import time
import numpy as np
def set_devices(): # creates device objects for all PSUs
class Axis:
def __init__(self, device, PSU_channel, arduino_pin):
self.device = device # power supply object (PS2000B class)
self.channel = PSU_channel # power supply unit channel (1 or 2)
self.ardPin = arduino_pin # output pin on the arduino for switching polarity on this axis
self.resistance = 0 # [Ohm]
# maximum allowable values to pass through this circuit
self.max_watts = 0 # [W]
self.max_amps = 0 # [A]
self.max_volts = 0 # [V]
self.coil_constant = 0 # coil constant of this axis [T/A]
self.ambient_field = 0 # ambient field in this axis [T]
# ToDo: get this info from settings file
def print_status(self): # axis = axis control variable, stored in settings.py
print("%s, %0.2f V, %0.2f A"
% (self.device.get_device_status_information(self.channel),
self.device.get_voltage(self.channel), self.device.get_current(self.channel)))
def power_down(self): # temporary powerdown, set outputs to 0 but keep connections enabled
self.device.voltage1 = 0
self.device.current1 = 0
g.ARDUINO.digitalWrite(self.ardPin, "LOW")
def set_signed_current(self, value): # sets current with correct polarity on this axis
device = self.device
channel = self.channel
ardPin = self.ardPin
if abs(value) > self.max_amps: # prevent excessive currents
shut_down_all() # safe all devices
raise ValueError("Invalid current value. Tried %0.2fA, max. %0.2fA allowed" % (value, self.max_amps))
elif value >= 0: # switch polarity as needed
g.ARDUINO.digitalWrite(ardPin, "LOW")
elif value < 0:
g.ARDUINO.digitalWrite(ardPin, "HIGH")
else:
raise Exception("This should be impossible.")
device.set_current(abs(value), channel)
maxVoltage = min(max(1.1 * self.max_amps * self.resistance, 8), self.max_volts) # limit voltage
device.set_voltage(maxVoltage)
def set_field_simple(self, value): # forms magnetic field as specified by value, w/o cancelling ambient field
current = value / self.coil_constant
self.set_signed_current(current)
def set_field(self, value): # forms magnetic field as specified by value, corrected for ambient field
field = value - self.ambient_field
current = field / self.coil_constant
self.set_signed_current(current)
def setup_axes(): # creates device objects for all PSUs and sets their values
g.XY_DEVICE = PS2000B.PS2000B(g.XY_PORT)
g.Z_DEVICE = PS2000B.PS2000B(g.Z_PORT)
g.X_AXIS = (g.XY_DEVICE, 0, g.RELAY_PINS[0], 0) # (device, channel, arduino pin, axis index)
g.Y_AXIS = (g.XY_DEVICE, 1, g.RELAY_PINS[1], 1)
g.Z_AXIS = (g.Z_DEVICE, 0, g.RELAY_PINS[2], 2)
g.X_AXIS = Axis(g.XY_DEVICE, 0, g.RELAY_PINS[0])
g.Y_AXIS = Axis(g.XY_DEVICE, 1, g.RELAY_PINS[1])
g.Z_AXIS = Axis(g.Z_DEVICE, 0, g.RELAY_PINS[2])
g.axes = [g.X_AXIS, g.Y_AXIS, g.Z_AXIS]
i = 0
for axis in g.AXES:
axis.resistance = g.RESISTANCES[i]
axis.max_watts = g.MAX_WATTS[i]
axis.max_amps = np.sqrt(axis.max_watts / axis.resistance)
axis.max_volts = g.MAX_VOLTS[i]
axis.coil_constant = g.COIL_CONST[i]
axis.ambient_field = g.AMBIENT_FIELD[i]
i = i+1
def activate_all(): # enables remote control and output on all PSUs and channels
@@ -33,20 +99,13 @@ def safe_arduino(): # sets output pins to low and closes serial connection
g.ARDUINO.digitalWrite(pin, "LOW")
def print_status(axis): # axis = axis control variable, stored in globals.py
device = axis[0] # PSU
channel = axis[1] # output channel on the PSU
print("%s, %0.2f V, %0.2f A"
% (device.get_device_status_information(channel), device.get_voltage(channel), device.get_current(channel)))
def print_status_3():
print("X-Axis:")
print_status(g.X_AXIS)
g.X_AXIS.print_status()
print("Y-Axis:")
print_status(g.Y_AXIS)
g.Y_AXIS.print_status()
print("Z-Axis:")
print_status(g.Z_AXIS)
g.Z_AXIS.print_status()
def set_to_zero(device): # sets voltages and currents to 0
@@ -56,13 +115,13 @@ def set_to_zero(device): # sets voltages and currents to 0
device.current2 = 0
def power_down(): # temporary, set all outputs to 0 but keep connections enabled
def power_down_all(): # temporary, set all outputs to 0 but keep connections enabled
set_to_zero(g.XY_DEVICE)
set_to_zero(g.Z_DEVICE)
safe_arduino()
def shut_down(): # shutdown at program end, set outputs to 0 and disable connections
def shut_down_all(): # shutdown at program end or on error, set outputs to 0 and disable connections
set_to_zero(g.XY_DEVICE)
set_to_zero(g.Z_DEVICE)
deactivate_all()
@@ -71,41 +130,18 @@ def shut_down(): # shutdown at program end, set outputs to 0 and disable connec
def set_field_simple(vector): # forms magnetic field as specified by vector, w/o cancelling ambient field
i_vec = vector/g.COIL_CONST
set_current_vec(i_vec)
for i in [0, 1, 2]:
g.AXES[i].set_field_simple(vector[i])
def set_field(vector): # forms magnetic field as specified by vector, corrected for ambient field
field = vector - g.AMBIENT_FIELD
i_vec = field/g.COIL_CONST
set_current_vec(i_vec)
for i in [0, 1, 2]:
g.AXES[i].set_field(vector[i])
def set_current_vec(i_vec): # sets needed currents on each axis for given vector
set_axis_current(g.X_AXIS, i_vec[0])
set_axis_current(g.Y_AXIS, i_vec[1])
set_axis_current(g.Z_AXIS, i_vec[2])
def set_axis_current(axis, value): # sets current with correct polarity on one axis
device = axis[0]
channel = axis[1]
ardPin = axis[2]
axisIndex = axis[3]
if abs(value) > g.MAX_AMPS[axisIndex]: # prevent excessive currents
set_to_zero(device) # set currents and voltages to 0
device.disable_all() # disable outputs on PSU
safe_arduino() # set arduino pins to low and close serial link
raise ValueError("Invalid current value. Tried %0.2fA, max. %0.2fA allowed" % (value, g.MAX_AMPS[axisIndex]))
elif value >= 0: # switch polarity as needed
g.ARDUINO.digitalWrite(ardPin, "LOW")
elif value < 0:
g.ARDUINO.digitalWrite(ardPin, "HIGH")
else:
raise Exception("This should be impossible.")
device.set_current(abs(value), channel)
maxVoltage = min(max(1.1 * g.MAX_AMPS[axisIndex] * g.RESISTANCES[axisIndex], 12), g.MAX_VOLTS) # limit voltage
device.set_voltage(maxVoltage)
for i in [0, 1, 2]:
g.AXES[i].set_signed_current(i_vec[i])
def execute_csv(filepath, printing=0): # runs through csv file containing times and desired field vectors
@@ -129,4 +165,4 @@ def execute_csv(filepath, printing=0): # runs through csv file containing times
print_status_3()
t_ref = t
print("File executed, powering down channels.")
power_down() # set currents and voltages to 0, set arduino pins to low
power_down_all() # set currents and voltages to 0, set arduino pins to low