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我试图在 VPython 中可视化一个盒子问题是：我知道它是滚动俯仰和偏航，但 Vpython 的盒子 有属性“轴”和“向上”。如何将我的角度转换为这两个所需的向量？

这是一个显示 3 个轴和一个框的短代码。函数 setOrientation 应该改变盒子属性“向上”和“轴”提供的滚动、俯仰和偏航。

import vis

def setOrientation(element, roll, pitch, yaw):    
    element.axis = ???
    element.up = ???


vis.display(
    title='Board orientation',
    x=0, y=200,
    width=600, height=600,
    center=(0, 0, 0),
    forward=(1, 0.4, 1),
    up = (0,0,-1),
    lights =[
        vis.distant_light(direction=(0.22, 0.44, -0.88), color=vis.color.gray(0.8)),
        vis.distant_light(direction=(-0.88, -0.22, 0.44), color=vis.color.gray(0.3))], 
range = 5
)

# Draw all axes
startingpoint = vis.sphere(pos=vis.vector(0, 0, 0), radius=0.2, color=vis.color.yellow)
vis.arrow(pos=startingpoint.pos, axis=vis.vector(3, 0, 0), shaftwidth=0.1, color=vis.color.red)
vis.arrow(pos=startingpoint.pos, axis=vis.vector(0, 3, 0), shaftwidth=0.1, color=vis.color.green)
vis.arrow(pos=startingpoint.pos, axis=vis.vector(0, 0, 3), shaftwidth=0.1, color=vis.color.blue)

#Make a box
mybox = vis.box(pos=(0,0,0), length=6, height=2, width=0.1, color=vis.color.red)
#Orient it by proviging roll, pitch and yaw
setOrientation(mybox, 0, 0, 0)

描述飞机的方向时，轴和方向应该匹配

X - 指向前方

Y - 指向右边

Z - 向下

roll - 正方向是顺时针

pitch - 积极向上

yaw - 正是顺时针

我发现的最接近的是Mike Smorto的代码

axis=(cos(pitch)*cos(yaw),-cos(pitch)*sin(yaw),sin(pitch)) 
up=(sin(roll)*sin(yaw)+cos(roll)*sin(pitch)*cos(yaw),sin(roll)*cos(yaw)-cos(roll)*sin(pitch)*sin(yaw),-cos(roll)*cos(pitch))

这个解决方案的问题是它的轴与我的问题不匹配，我无法修改它以满足我的需要。

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1 回答 1

0

您正在从一个身体四分法系统旋转到一个全局坐标系统。您可以使用四元数。

您可以使用它从滚动俯仰和偏航创建四元数。 

def QuaternionFromEuler(Roll, Pitch, Yaw):
    cRoll = math.cos(Roll/2)
    cPitch = math.cos(Pitch/2)
    cYaw = math.cos(Yaw/2)
    sRoll = math.sin(Roll/2)
    sPitch = math.sin(Pitch/2)
    sYaw = math.sin(Yaw/2)
    Quaternion = numpy.empty(4)
    Quaternion[0] = cRoll*cPitch*cYaw + sYaw*sPitch*sYaw
    Quaternion[1] = sRoll*cPitch*cYaw - cRoll*sPitch*sYaw
    Quaternion[2] = cRoll*sPitch*cYaw + cYaw*cPitch*sYaw
    Quaternion[3] = cRoll*cPitch*sYaw - sRoll*sPitch*cYaw
    return Quaternion
于 2014-08-03T19:38:44.603 回答