def test_vectorMagnetCylinder():
MAG = np.array([[0, 0, -44], [0, 0, 55], [11, 22, 33], [-14, 25, 36],
[17, -28, 39], [-10, -21, 32], [0, 12, 23], [0, -14, 25],
[16, 0, 27], [-18, 0, 29]])
POSM = np.ones([10, 3])
POSO = MAG * 0.1 * np.array([.8, -1, -1.3]) + POSM
DIM = np.ones([10, 2])
Bv = getBv_magnet('cylinder', MAG, DIM, POSM, POSO)
Bc = []
for mag, posM, posO, dim in zip(MAG, POSM, POSO, DIM):
pm = Cylinder(mag, dim, posM)
Bc += [pm.getB(posO)]
Bc = np.array(Bc)
assert np.amax(abs(Bv - Bc)) < 1e-15
# inside cylinder testing and iterDia
MAG = np.array([[0, 0, 1], [0, 1, 0], [1, 0, 0], [0, 1, 1], [1, 0, 1],
[1, 1, 0], [1, 1, 1]])
POSO = np.zeros([7, 3]) - .1
DIM = np.ones([7, 2])
POSM = np.zeros([7, 3])
Bv = getBv_magnet('cylinder', MAG, DIM, POSM, POSO, Nphi0=11)
Bc = []
for mag, posM, posO, dim in zip(MAG, POSM, POSO, DIM):
pm = Cylinder(mag, dim, posM, iterDia=11)
Bc += [pm.getB(posO)]
Bc = np.array(Bc)
assert np.amax(abs(Bv - Bc)) < 1e-15
d = 5 #distance magnet to center of tilt
thMAX = 15 #maximal joystick tilt angle
# define figure
fig = plt.figure(figsize=(7,6))
ax = plt.axes(projection='3d')
cm = plt.get_cmap("jet") #colormap
# set tilt angle
for th in np.linspace(1,thMAX,30):
# store fields here
Bs = np.zeros([181,3])
# create magnet for joystick in center position
s = Cylinder(dim=[D,H],mag=[0,0,M0],pos=[0,0,H/2+gap])
# set joystick tilt th
s.rotate(th,[0,1,0],anchor=[0,0,gap+H+d])
# rotate joystick for fixed tilt
for i in range(181):
# calculate field (sensor at [0,0,0]) and store in Bs
Bs[i] = s.getB([0,0,0])
# rotate magnet to next position
s.rotate(2,[0,0,1],anchor=[0,0,0])
# plot fields
ax.plot(Bs[:,0],Bs[:,1],Bs[:,2],color=cm(th/15))
# sample definition
demagnetizing_factor = 1/3 # sphere
volume = 4 / 3 * pi * (4 / 1000) ** 3 # V sphere r=4mm [m3]
M_saturation = 1.400e6 # Ms Co room temperature [A/m]
sample = {'demagnetizing_factor': demagnetizing_factor,
'volume': volume,
'M_saturation': M_saturation}
# magnet collection definition
m1 = Cylinder(mag=[0, 0, 1300], # 1300mT of magnetization along z axis
dim=[10, 20], # 10mm diameter, 20mm height
pos=[0, 0, -20]) # center is at z = -20mm
m2 = Cylinder(mag=[0, 0, 1300], # 1300mT of magnetization along z axis
dim=[10, 20], # 10mm diameter, 20mm height
pos=[0, 0, 20]) # center is at z = 20mm
both = Collection(m1, m2) # arrangement with both magnets
# magnet collection visualisation
displaySystem(both, suppress=True)
# 3D plot of B and F in a 3D space
# taken from https://magpylib.readthedocs.io/en/latest/_pages/2_guideExamples/ import numpy as np import matplotlib.pyplot as plt from magpylib.source.magnet import Cylinder import magpylib as magpy # create collection of two magnets s1 = Cylinder(mag=[0,0,1000], dim=[5,5]) s2 = Cylinder(mag=[0,0,-1000], dim=[2,6]) c = magpy.Collection(s1,s2) # create positions xs = np.linspace(-8,8,100) zs = np.linspace(-6,6,100) posis = [[x,0,z] for z in zs for x in xs] # calculate field and amplitude B = [c.getB(pos) for pos in posis] Bs = np.array(B).reshape([100,100,3]) #reshape Bamp = np.linalg.norm(Bs,axis=2) # define figure with a 2d and a 3d axis fig = plt.figure(figsize=(8,4)) ax1 = fig.add_subplot(121,projection='3d') ax2 = fig.add_subplot(122) # add displaySystem on ax1 magpy.displaySystem(c,subplotAx=ax1,suppress=True) ax1.view_init(elev=75)
import numpy as np import math import matplotlib.pyplot as plt from magpylib.source.magnet import Cylinder from magpylib.source.current import Circular from magpylib import Collection TURNS = 15 s = 91 LENGTH = 3 CURRENT = 1 # create magnets s2 = Cylinder(mag=(0,0,500), dim=(3,5)) coil1 = [Circular(curr=CURRENT,dim=LENGTH,pos=[0,0,z]) for z in np.linspace(-3,3,TURNS)] # create collection c1 = Collection(coil1) xs = np.linspace(0, 0,6) ys = np.linspace(0, 0,6) zs = np.linspace(-9, 9, s) F_POS = np.array([(x,y,z) for x in xs for y in ys for z in zs]) B = c1.getB(F_POS)[:s] mags = [ math.sqrt(sum(i**2 for i in x)) for x in B ] z_pos = [d for d in zs] derivative = np.diff(mags)/np.diff(zs) print(mags)
from magpylib.source.magnet import Box, Cylinder, Sphere
# Simuate a N38 5 * 5 *5 mm
#https://www.leeyed.com/rare_earth_magnet.html
s_Box = Box(mag=(0, 0, 1220), dim=(5, 5, 5), pos=(0, 0, -2.5))
s_Cylinder = Cylinder(mag=(0, 0, 1220),
dim=(5, 5),
pos=(0.0, 0.0, -2.5),
angle=0.0,
axis=(0.0, 0.0, 1.0),
iterDia=50)
s_Sphere = Sphere(mag=(0.0, 0.0, 1220),
dim=5.0,
pos=(0.0, 0.0, -2.5),
angle=0.0,
axis=(0.0, 0.0, 1.0))
print(s_Box.getB([0, 0, 5]))
print(s_Cylinder.getB([0, 0, 5]))
print(s_Sphere.getB([0, 0, 5]))
# taken from https://magpylib.readthedocs.io/en/latest/_pages/2_guideExamples/ import numpy as np import matplotlib.pyplot as plt from magpylib.source.magnet import Box, Cylinder from magpylib import Collection, displaySystem # create magnets s1 = Box(mag=(0, 0, 600), dim=(3, 3, 3), pos=(-4, 0, 3)) s2 = Cylinder(mag=(0, 0, 500), dim=(3, 5)) # create collection c = Collection(s1, s2) # manipulate magnets individually s1.rotate(45, (0, 1, 0), anchor=(0, 0, 0)) s2.move((5, 0, -4)) # manipulate collection c.move((-2, 0, 0)) # calculate B-field on a grid xs = np.linspace(-10, 10, 33) zs = np.linspace(-10, 10, 44) POS = np.array([(x, 0, z) for z in zs for x in xs]) Bs = c.getB(POS).reshape(44, 33, 3) #<--VECTORIZED # create figure fig = plt.figure(figsize=(9, 5)) ax1 = fig.add_subplot(121, projection='3d') # 3D-axis ax2 = fig.add_subplot(122) # 2D-axis
# taken from https://magpylib.readthedocs.io/en/latest/_pages/2_guideExamples/ from magpylib.source.magnet import Cylinder s = Cylinder( mag = [0,0,350], dim = [4,5]) print(s.getB([4,4,4]))
from magpylib.source.magnet import Cylinder
import matplotlib.pyplot as plt
import numpy as np
import magpylib.math as math
#system parameters
D, H = 5, 4 #magnet dimension
M0 = 1200 #magnet magnetization amplitude
gap = 3 #airgap
d = 5 #distance magnet to center of tilt
thMAX = 15 #maximal joystick tilt angle
#create magnet
s = Cylinder(dim=[D, H], mag=[0, 0, M0])
#initial central magnet position
p0 = [0, 0, H / 2 + gap]
#generate rotation axes
axes = [[np.cos(phi), np.sin(phi), 0]
for phi in np.linspace(0, 2 * np.pi, 180)]
#generate a type2 INPUT
INPUT = []
for th in np.linspace(1, thMAX, 30):
#rotation of the magnet position outwards
posis = [
math.rotatePosition(p0, th, ax, anchor=[0, 0, gap + H + d])
for ax in axes
]