Yaw rotation of gear object in vpython-CodePudding

I was wondering how to yaw gear object about Y-axis in vpython. I have been following some tutorials and I have managed to rotate the gear. The gear rotates about Z axis in vpython. I want the gear to remain rotating about Z axis but I would like to yaw the gear around Y-axis. When xxx.rotate(axis=vector(0,0,1), it works as it should do. As soon as I alter anything it goes crazy. I am not sure what xxx.rotate(origin) is meant to do. In my case, I have messed around with the origin vector but it doesn't make any sense to me. I am not sure if the origin vector expects parameter values in x,y,z or some other sequence. I hope I am making makes sense.

The code below is a working code and you can see what I am trying to do here. I have been debugging for a while so please ignore unnecessary comments.

# https://www.youtube.com/watch?v=0Sw8sxsN984
# https://www.youtube.com/watch?v=MJiVtz4Uj7M

from vpython import *
import numpy as np

axisOpac = 0.4

def makeAxes(length):
    
    global axes

    xaxis = arrow(pos=vector(0, 0, 0), axis=length*vector(1,0,0), shaftwidth = 0.1*(length), color=color.red, opacity = axisOpac)
    negXaxis = xaxis.clone()
    negXaxis.axis *= -1

    yaxis = arrow(pos=vector(0, 0, 0), axis=length*vector(0,1,0), color=color.green, opacity = axisOpac)
    negYaxis = yaxis.clone()
    negYaxis.axis *= -1

    zaxis = arrow(pos=vector(0, 0, 0), axis=length*vector(0,0,1), color=color.magenta, opacity = axisOpac)
    negZaxis = zaxis.clone()
    negZaxis.axis *= -1    

    fudge = 0.01*length
    xlabel = label(text = "x", color = xaxis.color, pos=xaxis.axis vector(0, fudge, 0),box = False)
    ylabel = label(text = "y", color = yaxis.color, pos=yaxis.axis vector(0, fudge, 0),box = False)
    zlabel = label(text = "-z", color = zaxis.color, pos=zaxis.axis vector(0, fudge, 0),box = False)
    
    # To make axes visible or invisible
    axes = [xaxis, negXaxis, yaxis, negYaxis, zaxis, negZaxis, xlabel, ylabel, zlabel]

    return

makeAxes(1)

g = shapes.gear(n = 20)

gear1 = extrusion (path = [vector(0, 0, 0), vector(0, 0, 0.1)], shape=g, opacity = 0.4)
# gear1.axis = vector(0, 0, 0)

debugArrow=arrow(length=6,shaftwidth=.1,color=color.white,axis=vector(0,0,0))
gearAxisArrow=arrow(shaftwidth=.1, color=color.red)

inputYawAngleYaxis = 0 # int(input("Enter an angle: "))

while True:
    for cir in np.arange(0, 2*np.pi, 0.01):
        rate(10)
        # sleep(1)

        pitch=0
        # k = vector(cos(yaw)*cos(pitch), sin(pitch),sin(yaw)*cos(pitch))  ''' with pitch input '''
        k = vector(cos(cir), 0 ,sin(cir))  # ''' without pitch input '''
        y=vector(0,0,0)
        s=cross(k,y)
        v=cross(s,k)



        rad = radians(45)
        # gear1.axis = vector(1.23, -1.77418, 0) #vector(cos(inputYawAngleYaxis * pi/180), sin(pitch),sin(inputYawAngleYaxis* pi/180)*cos(pitch))
        # gear1.pos = vector(-2.94957, 0, 2.70185)
        
        # Gear Pos0:  <0.707107, 0, 0.707107>  Gear Axis0:  <2.15647, 0.101243, -0.00237659>
        gear1.pos = vector(0.707107, 0, 0.707107)
        # gear1.pos =  debugArrow.axis #frontArrow.axis # k # vector(0.707107, 0, 0.707107)
        gear1.rotate(angle = -0.1, axis = vector(0, 0, 1), origin = vector(0, 0, 1 ))
        # gear1.axis = vector(cos(radians(-45)), 0, sin(radians(-45))) 

        ''' DebugArrow represents the position of the gear's center '''
        debugArrow.axis = vector(cos(rad), 0, sin(rad))


        ''' Arrow inside the gear to track rotational axis of gear - This is to debug the yaw issue facing with gear object'''
        gearAxisArrow.pos = gear1.pos
        gearAxisArrow.axis = gear1.axis # vector(cos(radians(-45)), 0, sin(radians(-45))) # gear1.axis
        gearAxisArrow.length = gear1.length/2
        
            ## Debugg 
        # print("Front Arrow Axis: ", frontArrow.axis, " K vec: ", k, " Ball pos: ", ball.pos )
        print("Gear Pos0: ", gear1.pos, " Gear Axis0: ", gear1.axis, "gearAxisArrow: ", gearAxisArrow.pos, "gearAxisArrow: ", gearAxisArrow.axis)

CodePudding user response：

I don't understand "I want the gear to remain rotating about Z axis but I would like to yaw the gear around Y-axis". If by "yaw" you mean that the axis of the gear should rotate about the y axis (while the gear itself rotates about that rotating axis), then obviously the axis of the gear can't remain in the direction of the z axis. Instead, the axis of the gear has to rotate. If it's of any help, here is the relevant page of the documentation:

https://www.glowscript.org/docs/VPythonDocs/rotation.html

CodePudding user response：

I'm sorry for not being very clear. What I meant is, the gear is always facing X axis. I can move it around but I can't orient the gear in the direction shown in blue arrow in pic below. Thats what I meant by Yaw. https://m.imgur.com/iWECUSK