visualpython-users

[Visualpython-users] Visual Python Help

[Kailas N. <ka...@my...>]

Hi!  I'm working on a program in visual python and am running into a
weird problem (maybe it's my own user error, but I can't see what I'm
doing wrong)

To run the attached code, need wxpython installed too.

In my code, I've got a "human body" constructed using some primitive
blocks, cylinders, etc.  I want to be able to model upper torso
movement, as well as arm movement that's recorded by some sensors placed
around the body.

The arm movement works great, and I can easily control the position and
rotation of the upper arm and elbow (all that I'm interested in).

The torso is behaving a bit strangely.

I have a Box object I create:

Chest = box ( pos=(0,HeadDiameter+SegmentSpace+HeadDiameter/2,0),
axis=(2*HeadDiameter,0,0), width=.75, height=HeadDiameter,
length=2*HeadDiameter, color=color.red)

And based on the "pitch", "yaw" and "heading" angles, I can rotate it.
When the chest pitches forward, it needs to rotate about the line that
goes through the gap between the torso and stomach, so I do the
rotations with the vectors, moving the position of the chest block, as
well as rotating it.  (I actually tried the Rotate function for the
block itself with no success)

#(utp=pitch, uth=heading, uty=yaw)

	cloc=UTOrigin+rotate(UTUnitAxis,utp,(1,0,0))*HeadDiameter/2
	caxis=rotate( (HeadDiameter*2,0,0), utp,(1,0,0) )	####
!!!! Why doesn't this make the check pitch forward?
	caxis=rotate(caxis,uty,(0,0,1))
	caxis=rotate(caxis,uth,(0,1,0))

	Chest.pos=cloc
	Chest.axis=caxis

As you can see from the code, for some reason the rotation that's
supposed to happen about the long axis of the box doesn't.  the strange
thing is that the other ones work ok, so I'm not sure what I'm doing
wrong.

I've attached the code if you want to try and run it.  The problem is on
line 48.  You'll notice that the arm doesn't follow the torso just yet,
which is ok.

Any ideas?

Thanks!

-kailas

Re: [Visualpython-users] Visual Python Help

[Ron A. <rr...@ro...>]

Kailas Narendran wrote:

> 
> As you can see from the code, for some reason the rotation that's
> supposed to happen about the long axis of the box doesn't.  the strange
> thing is that the other ones work ok, so I'm not sure what I'm doing
> wrong.
> 
> I've attached the code if you want to try and run it.  The problem is on
> line 48.  You'll notice that the arm doesn't follow the torso just yet,
> which is ok.
> 
> Any ideas?

I played around with your program a bit and found it easier to group parts 
in frames.

Attached is what I got so far.  I think this will be easier for you to extend.

Cheers,
    Ron

Re: [Visualpython-users] Visual Python Help

[<bre...@un...>]

Interesting and a nice "refactoring".

I just started with vPython (but already know Python somewhat) and assumed 
that to create groups one would derive classes from frame, as shown.  It 
seems to work, but is this not preferred/robust?

import visual as v

class Wheelset(v.frame):

    def __init__(self, xPos, whlRad=0.5, etc):

        v.frame.__init__(self, pos=(xPos,whlRad,0.0))
 
        v.cylinder(frame=self, pos=(0,0,-0.5*axleLength),
                   axis=(0.0, 0.0, axleLength), radius=axlRad)
       etc




Ron Adam <rr...@ro...> 
Sent by: vis...@li...
07/02/2008 09:04 AM

To
vis...@li...
cc
pub...@ci...
Subject
Re: [Visualpython-users] Visual Python Help








Kailas Narendran wrote:

> 
> As you can see from the code, for some reason the rotation that's
> supposed to happen about the long axis of the box doesn't.  the strange
> thing is that the other ones work ok, so I'm not sure what I'm doing
> wrong.
> 
> I've attached the code if you want to try and run it.  The problem is on
> line 48.  You'll notice that the arm doesn't follow the torso just yet,
> which is ok.
> 
> Any ideas?

I played around with your program a bit and found it easier to group parts 

in frames.

Attached is what I got so far.  I think this will be easier for you to 
extend.

Cheers,
    Ron



______________________________________________________________________
This email has been scanned by the MessageLabs Email Security System.
For more information please visit http://www.messagelabs.com/email 
______________________________________________________________________"""
    Apollo Body

"""
import wx
from visual import *
from math import pi


class Hand(object):
    color = color.green
    radius = .25
    def __init__(self, parent, pos):
        self.obj = frame(frame=parent, pos=pos)
        sphere(frame=self.obj, radius=self.radius, color=self.color)
 

class ForeArm(object):
    color = color.blue
    axis = (1, 0, 0)
    elboaxis = (0, 1, 0)
    radius = .2
    def __init__(self, parent, pos):
        self.obj = frame(frame=parent, pos=pos)
        cylinder(frame=self.obj, axis=self.axis, radius=self.radius,
                 color=self.color)
        self.bendpos = 0.0

    def position(self, bend):
        # Elbo bend
        bend = pi * .5 + bend * .50   # Reduce range
        anglediff = self.bendpos - bend
        self.obj.rotate(angle=anglediff, axis=self.elboaxis)
        self.bendpos = bend


class UpperArm(object):
    color = color.blue
    axis = (1, 0, 0)
    radius = .2
    def __init__(self, parent, pos):
        self.obj = frame(frame=parent, pos=pos)
        cylinder(frame=self.obj, axis=self.axis, radius=self.radius,
                 color=self.color)
        self.rollpos = 0.0
        self.pitchpos = 0.0
        self.headingpos = 0.0

    def position(self, heading, pitch, roll):
        # Arm point
        heading *= .50   # Reduce range
        anglediff = self.headingpos - heading
        self.obj.rotate(angle=anglediff, axis=(0, 0, 1))
        self.headingpos = heading

        # Arm raise
        pitch *= .50   # Reduce range
        anglediff = self.pitchpos - pitch
        self.obj.rotate(angle=anglediff, axis=(1, 0, 0))
        self.pitchpos = pitch

        # Arm twist
        roll *= .90   # Reduce range
        anglediff = self.rollpos - roll
        self.obj.rotate(angle=anglediff, axis=(0, 1, 0))
        self.rollpos = roll


class Chest(object):
    color = color.red
    axis = (2, 0, 0)
    width = .75
    def __init__(self, parent, pos):
        self.obj = frame(frame=parent, pos=pos)
        box(frame=self.obj, pos=(0,1,0), axis=self.axis,
            width=self.width, color=self.color)
        self.headingpos = 0.0
        self.pitchpos = 0.0
        self.yawpos = 0.0

    def position(self, heading, pitch, yaw): 
        # Turn Left or Right.
        heading *= .50   # Reduce range
        anglediff = self.headingpos - heading
        self.obj.rotate(angle=anglediff, axis=(0, 1, 0))
        self.headingpos = heading

        # Bend forward or back.
        pitch *= .50   # Reduce range
        anglediff = self.pitchpos - pitch
        self.obj.rotate(angle=anglediff, axis=(1, 0, 0))
        self.pitchpos = pitch
 
        # Lean left or right.
        yaw *= .10   # Reduce range
        anglediff = self.yawpos - yaw
        self.obj.rotate(angle=anglediff, axis=(0, 0, 1))
        self.yawpos = yaw
 

class Head(object):
    radius = .5
    color = color.red
    def __init__(self, parent, pos):
        self.obj = frame(frame=parent, pos=pos)
        sphere(frame=self.obj, radius=self.radius, color=self.color)


class Stomach(object):
    color = color.red
    width = .75
    height = 1
    length = 1.5
    def __init__(self, parent, pos):
        self.obj = frame(frame=parent, pos=pos)
        box(frame=self.obj, width=self.width, height=self.height,
            length=self.length, color=self.color)


# Build the body.
#
# Larger parts act as frames for smaller parts so
# they rotate and move together.

body = frame()
stomach = Stomach(body, (0, 0, 0))
chest = Chest(stomach.obj, (0, .25, 0))
head = Head(chest.obj, (0, 2.25, 0))
upper_arm = UpperArm(chest.obj, (1.25, 1.5, 0)) 
fore_arm = ForeArm(upper_arm.obj, (1.25, 0, 0))
hand = Hand(fore_arm.obj, (1.5, 0, 0))

def position(utp, uty, uth, p, h, r, e):
    # Update body position.
    fore_arm.position(e)
    upper_arm.position(h, p, r)
    chest.position(uth, utp, uty)


ID_ABOUT=101
ID_EXIT=110
class MainWindow(wx.Frame):
    def __init__(self,parent,id,title):
        wx.Frame.__init__(self,parent,wx.ID_ANY, title, size = (400,600))
 
        #self.control = wx.TextCtrl(self, 1, style=wx.TE_MULTILINE)
        self.CreateStatusBar() # A Statusbar in the bottom of the window   
 
        panel = wx.Panel(self, -1)

        # Setting up the menu.
        filemenu= wx.Menu()
        filemenu.Append(ID_ABOUT, "&About"," Information about this 
program")
        filemenu.AppendSeparator()
        filemenu.Append(ID_EXIT,"E&xit"," Terminate the program")
 
        # Creating the menubar.
        menuBar = wx.MenuBar()
        # Adding the "filemenu" to the MenuBar
        menuBar.Append(filemenu, "&File")
 
        # Create the sliders
        font1 = wx.Font(15, wx.NORMAL, wx.ITALIC, wx.NORMAL)

        # Uppor torso pitch
        hboxutp = wx.BoxSizer(wx.HORIZONTAL)
        utpl = wx.StaticText(panel, -1, "Upper Torso Pitch", (45, 25),
                           style=wx.ALIGN_CENTRE)
        utpl.SetFont(font1)
        hboxutp.Add(utpl, 1, wx.EXPAND)
        self.UpperTorsoPitch = wx.Slider(panel, -1, 0, -100, 100,
                                         wx.DefaultPosition, (10, -1),
                                         wx.SL_HORIZONTAL | wx.SL_LABELS)
        hboxutp.Add(self.UpperTorsoPitch,1,wx.EXPAND)

        # Upper torso yaw
        hboxuty = wx.BoxSizer(wx.HORIZONTAL)
        utyl = wx.StaticText(panel, -1, "Upper Torso Yaw", (45, 25),
                           style=wx.ALIGN_CENTRE)
        utyl.SetFont(font1)
        hboxuty.Add(utyl, 1, wx.EXPAND)
        self.UpperTorsoYaw = wx.Slider(panel, -1, 0, -100, 100,
                                       wx.DefaultPosition, (10, -1),
                                       wx.SL_HORIZONTAL | wx.SL_LABELS)
        hboxuty.Add(self.UpperTorsoYaw,1,wx.EXPAND)

        # Upper torso heading
        hboxuth = wx.BoxSizer(wx.HORIZONTAL)
        uthl=wx.StaticText(panel, -1, "Upper Torso Heading", (45, 25),
                           style=wx.ALIGN_CENTRE)
        uthl.SetFont(font1)
        hboxuth.Add(uthl, 1, wx.EXPAND)
        self.UpperTorsoHeading = wx.Slider(panel, -1, 0, -100, 100,
                                           wx.DefaultPosition, (10, -1),
                                           wx.SL_HORIZONTAL | 
wx.SL_LABELS)
        hboxuth.Add(self.UpperTorsoHeading,1,wx.EXPAND)

        # arm pitch
        hboxuap = wx.BoxSizer(wx.HORIZONTAL)
        uapl = wx.StaticText(panel, -1, "Upper Arm Roll", (45, 25),
                             style=wx.ALIGN_CENTRE)
        uapl.SetFont(font1)
        hboxuap.Add(uapl, 1, wx.EXPAND)
        self.UpperArmPitch = wx.Slider(panel, -1, 0, -100, 100,
                                       wx.DefaultPosition, (10, -1),
                                       wx.SL_HORIZONTAL | wx.SL_LABELS)
        hboxuap.Add(self.UpperArmPitch, 1, wx.EXPAND)

        # Upper arm yaw
        hboxuay = wx.BoxSizer(wx.HORIZONTAL)
        uayl = wx.StaticText(panel, -1, "Upper Arm Yaw", (45, 25),
                             style=wx.ALIGN_CENTRE)
        uayl.SetFont(font1)
        hboxuay.Add(uayl,1,wx.EXPAND)
        self.UpperArmYaw = wx.Slider(panel, -1, 0, -100, 100,
                                     wx.DefaultPosition, (10, -1),
                                     wx.SL_HORIZONTAL | wx.SL_LABELS)
        hboxuay.Add(self.UpperArmYaw, 1, wx.EXPAND)

        # Upper arm heading
        hboxuah = wx.BoxSizer(wx.HORIZONTAL)
        uahl = wx.StaticText(panel, -1, "Upper Arm Heading", (45, 25),
                             style=wx.ALIGN_CENTRE)
        uahl.SetFont(font1)
        hboxuah.Add(uahl, 1, wx.EXPAND)
        self.UpperArmHeading = wx.Slider(panel, -1, 0, -100, 100,
                                         wx.DefaultPosition, (10, -1),
                                         wx.SL_HORIZONTAL | wx.SL_LABELS)
        hboxuah.Add(self.UpperArmHeading, 1, wx.EXPAND)

        # Elbow angle
        hboxe = wx.BoxSizer(wx.HORIZONTAL)
        el = wx.StaticText(panel, -1, "Elbow Angle", (45, 25),
                           style=wx.ALIGN_CENTRE)
        el.SetFont(font1)
        hboxe.Add(el, 1, wx.EXPAND)
        self.ElbowAngle = wx.Slider(panel, -1, 0, -100, 100,
                                    wx.DefaultPosition, (10, -1),
                                    wx.SL_HORIZONTAL | wx.SL_LABELS)
        hboxe.Add(self.ElbowAngle, 1, wx.EXPAND)


        vbox = wx.BoxSizer(wx.VERTICAL)
        vbox.Add(hboxutp, 1, wx.EXPAND)
        vbox.Add(hboxuty, 1, wx.EXPAND)
        vbox.Add(hboxuth, 1, wx.EXPAND)
        vbox.Add(hboxuap, 1, wx.EXPAND)
        vbox.Add(hboxuay, 1, wx.EXPAND)
        vbox.Add(hboxuah, 1, wx.EXPAND)
        vbox.Add(hboxe, 1, wx.EXPAND)
 
        wx.EVT_MENU(self, ID_ABOUT, self.OnAbout)
        wx.EVT_MENU(self, ID_EXIT, self.OnExit) 

        wx.EVT_COMMAND_SCROLL(self.ElbowAngle, self.ElbowAngle.GetId(),
                              self.OnAngleSliderChange) 
        wx.EVT_COMMAND_SCROLL(self.UpperArmPitch, 
self.UpperArmPitch.GetId(),
                              self.OnAngleSliderChange) 
        wx.EVT_COMMAND_SCROLL(self.UpperArmYaw, self.UpperArmYaw.GetId(),
                              self.OnAngleSliderChange) 
        wx.EVT_COMMAND_SCROLL(self.UpperArmHeading, 
self.UpperArmHeading.GetId(),
                              self.OnAngleSliderChange) 
        wx.EVT_COMMAND_SCROLL(self.UpperTorsoHeading, 
self.UpperTorsoHeading.GetId(),
                              self.OnAngleSliderChange)
        wx.EVT_COMMAND_SCROLL(self.UpperTorsoPitch, 
self.UpperTorsoPitch.GetId(),
                              self.OnAngleSliderChange)
        wx.EVT_COMMAND_SCROLL(self.UpperTorsoYaw, 
self.UpperTorsoYaw.GetId(),
                              self.OnAngleSliderChange)

        panel.SetSizer(vbox)
        panel.SetAutoLayout(1)
        self.SetMenuBar(menuBar)  # Adding the MenuBar to the Frame 
content.
        self.Show(True)

    def OnAngleSliderChange(self, event):
        e = self.ElbowAngle.GetValue()
        p = self.UpperArmPitch.GetValue()
        h = self.UpperArmHeading.GetValue()
        r = self.UpperArmYaw.GetValue()

        utp = self.UpperTorsoPitch.GetValue()
        uty = self.UpperTorsoYaw.GetValue()
        uth = self.UpperTorsoHeading.GetValue()

        e= e / 100.0 * pi
        p= p / 100.0 * pi
        h= h / 100.0 * pi
        r= r / 100.0 * pi

        utp = utp / 100.0 * pi
        uty = uty / 100.0 * pi
        uth = uth / 100.0 * pi

        position(utp, uty, uth, p, h, r, e)
 
    def OnAbout(self, event):
        # Create a message dialog box
        d= wx.MessageDialog( self, " A sample editor \n"
        " in wxPython","About Sample Editor", wx.OK)
        d.ShowModal() # Shows it
        d.Destroy() # finally destroy it when finished.
 
    def OnExit(self, event):
        self.Close(True)  # Close the frame.

app = wx.PySimpleApp()
frame = MainWindow(None, -1, "Apollo Body Control Panel")

app.MainLoop()
-------------------------------------------------------------------------
This SF.net email is sponsored by: Microsoft
Defy all challenges. Microsoft(R) Visual Studio 2008.
http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/
_______________________________________________
Visualpython-users mailing list
Vis...@li...
https://lists.sourceforge.net/lists/listinfo/visualpython-users



UNITED GROUP
This email message is the property of United Group. The information in this email is confidential and may be legally privileged. It is intended solely for the addressee. Access to this email by anyone else is unauthorised. If you are not the intended recipient, you may not disclose, copy or distribute this email, nor take or omit to take any action in reliance on it. United Group accepts no liability for any damage caused by this email or any attachments due to viruses, interference, interception, corruption or unauthorised access.
If you have received this email in error, please notify United Group immediately by email to the sender's email address and delete this document.

Re: [Visualpython-users] Visual Python Help

[Ron A. <rr...@ro...>]

bre...@un... wrote:
> 
> Interesting and a nice "refactoring".

Thanks :-)

> I just started with vPython (but already know Python somewhat) and 
> assumed that to create groups one would derive classes from frame, as 
> shown.  It seems to work, but is this not preferred/robust?
>
> import visual as v
> 
> class Wheelset(*v.frame*):
> 
>     def __init__(self, xPos, whlRad=0.5, /etc/):
> 
>         *v.frame.__init__(self,* pos=(xPos,whlRad,0.0)*)*
>        
>         v.cylinder(*frame=self*, pos=(0,0,-0.5*axleLength),
>                    axis=(0.0, 0.0, axleLength), radius=axlRad)
>        etc

When I tried a variation of the above with the Head() object, the class 
color attribute was overwritten.  The defaults could be moved to within the 
__init__ method, but then you may have the opposite problem of overwriting 
a frame attribute or method without knowing it.  So I think if there are a 
lot of methods or attributes, using a container obj makes it easier to 
avoid name clashes.  But it looks like, either way is ok.

Ron