cycloid ball reducer sketch for fusion360

got_balls.py

import adsk.core, adsk.fusion, adsk.cam, traceback, math
import sys, os
packagepath = os.path.join(os.path.dirname(sys.argv[0]), 'Lib/site-packages/')
if packagepath not in sys.path:
    sys.path.append(packagepath)
#import numpy as np
#np = math



def run(context):
    ui = None
    try:
        app = adsk.core.Application.get()
        ui  = app.userInterface
        install_numpy = sys.path[0] +'\Python\python.exe -m pip install numpy'
        try:
            import numpy as np
        except:
            ui.messageBox('failed to install numpy\n{}'.format(traceback.format_exc()))
        #ui.messageBox('Hello script')       
        design = app.activeProduct
        # Get the root component of the active design.       
        rootComp = design.rootComponent     
        # Create a new sketch on the xy plane.       
        sketches = rootComp.sketches       
        xyPlane = rootComp.xYConstructionPlane        
        sketch = sketches.add(xyPlane)

        # Create an object collection for the points.        
        points = adsk.core.ObjectCollection.create()              
        Dia = 10 #Diameter of the pin circle                
        #R = Dia/2 # Radius of the toro        
        #E = 0.3 # Eccentricity of input shaft        
        Rr = 0.3 # Radius of the rollers        
        #N = 19 # Number of rollers        
        n = 10 # num rollers
        e = .2 # eccentricity
        d = Rr * 2 # roller diameter

        

        i = 0        
        shaft_radius = .8
        splinePoints = (n -1) * 20
        t = np.linspace(0, 2*np.pi, splinePoints)

        RD=Dia/2 # ring radius
        rd=d/2  # roller radius same as Rr
        rc = (n-1)*(RD/n)
        rm = (RD/n) # 

        # draw a shaft circle
        circles = sketch.sketchCurves.sketchCircles
        circle1 = circles.addByCenterRadius(adsk.core.Point3D.create(0, 0, 0), shaft_radius)
        circleA = circles.addByCenterRadius(adsk.core.Point3D.create((rc+rm) - rd,0,0),1)
        inner_pinA = circles.addByCenterRadius( adsk.core.Point3D.create((-rd - (2 * e)), 0,0),0.2)

        # moving eccentric inner
        # ehypocycloidA

        xa = (rc+rm)*np.cos(t)-e*np.cos((rc+rm)/rm*t)
        ya = (rc+rm)*np.sin(t)-e*np.sin((rc+rm)/rm*t)

        dxa = (rc+rm)*(-np.sin(t)+(e/rm)*np.sin((rc+rm)/rm*t))
        dya = (rc+rm)*(np.cos(t)-(e/rm)*np.cos((rc+rm)/rm*t))
        xCoord = xa + rd/np.sqrt(dxa**2 + dya**2)*(-dya) 
        yCoord = ya + rd/np.sqrt(dxa**2 + dya**2)*dxa 

        for i in range(splinePoints):
            points.add(adsk.core.Point3D.create(xCoord[i],yCoord[i],0))                   

        sketch.sketchCurves.sketchFittedSplines.add(points)

        # moving eccentric  outer
        # ehypocycloidE
        points = adsk.core.ObjectCollection.create()


        rc = (n-1)*(RD/n)
        rm = (RD/n)
        xa = (rc+rm)*np.cos(t)-e*np.cos((rc+rm)/rm*t)
        ya = (rc+rm)*np.sin(t)-e*np.sin((rc+rm)/rm*t)

        dxa = (rc+rm)*(-np.sin(t)+(e/rm)*np.sin((rc+rm)/rm*t))
        dya = (rc+rm)*(np.cos(t)-(e/rm)*np.cos((rc+rm)/rm*t))

        xCoord = xa - rd/np.sqrt(dxa**2 + dya**2)*(-dya) 
        yCoord = ya - rd/np.sqrt(dxa**2 + dya**2)*dxa
        for i in range(splinePoints):
            points.add(adsk.core.Point3D.create(xCoord[i],yCoord[i],0))  

        sketch.sketchCurves.sketchFittedSplines.add(points)

        #  Add moving eccentric disk  od
        # ehypocycloidD
        sketch = sketches.add(xyPlane)
        circles = sketch.sketchCurves.sketchCircles
        # should be eccentric
        circle1 = circles.addByCenterRadius(adsk.core.Point3D.create(0, 0, 0), shaft_radius)
        circleD = circles.addByCenterRadius(adsk.core.Point3D.create((rc+rm) - rd, 0,0),0.1)
        points = adsk.core.ObjectCollection.create()

        rc = (n+1)*(RD/n)
        rm = (RD/n)
        xa = (rc-rm)*np.cos(t)+e*np.cos((rc-rm)/rm*t)
        ya = (rc-rm)*np.sin(t)-e*np.sin((rc-rm)/rm*t)

        dxa = (rc-rm)*(-np.sin(t)-(e/rm)*np.sin((rc-rm)/rm*t))
        dya = (rc-rm)*(np.cos(t)-(e/rm)*np.cos((rc-rm)/rm*t))

        xCoord = xa - rd/np.sqrt(dxa**2 + dya**2)*(-dya) 
        yCoord = ya - rd/np.sqrt(dxa**2 + dya**2)*dxa


        for i in range(splinePoints):
            points.add(adsk.core.Point3D.create(xCoord[i],yCoord[i],0))

        sketch.sketchCurves.sketchFittedSplines.add(points)

        #  Add moving eccentric disk  id
        # ehypocycloidF
        points = adsk.core.ObjectCollection.create()
        i = 0

        rc = (n+1)*(RD/n)
        rm = (RD/n)
        xa = (rc-rm)*np.cos(t)+e*np.cos((rc-rm)/rm*t)
        ya = (rc-rm)*np.sin(t)-e*np.sin((rc-rm)/rm*t)

        dxa = (rc-rm)*(-np.sin(t)-(e/rm)*np.sin((rc-rm)/rm*t))
        dya = (rc-rm)*(np.cos(t)-(e/rm)*np.cos((rc-rm)/rm*t))

        xCoord = xa + rd/np.sqrt(dxa**2 + dya**2)*(-dya) 
        yCoord = ya + rd/np.sqrt(dxa**2 + dya**2)*dxa
        for i in range(splinePoints):
            points.add(adsk.core.Point3D.create(xCoord[i],yCoord[i],0))

        sketch.sketchCurves.sketchFittedSplines.add(points)

            
    except:
        if ui:
            ui.messageBox('Failed:\n{}'.format(traceback.format_exc()))