Sado Rabaudi
OptiTrack allows motion capture for virtual reality, movement science, animation, robotics and more. Here are the workflows for connecting OptiTrack to Vizard:
1. Either load in pre-recorded data or set up live streaming in Motive (NOTE: For "Live" data you need to have a named skeleton assigned to the markers).
2. Use these setting in Motive (under Edit- Settings)
Note: You may also have to press the edit advanced button in the settings to redefine the IP in motive
3. Create a new Vizard script and run this code in order to get the names of the Motive Body Parts (where “localhost” is the server address of the machine running Motive). Press spacebar to print these values
import viz
viz.go()
#Connect to OptiTrack Motive server
optitrack = viz.add('optitrack.dle')
motive = optitrack.addMotive('localhost')
def printBodyData():
for s in motive.getSkeletonList():
for b in s.getBodyList():
print(b.getName())
print(s.getName())
vizact.onkeydown(' ',printBodyData)
4. Create a new vizconnect file and create group trackers for each of the body parts by going to the Trackers tab and choosing “Add a New Tracker” - “Group Tracker” and naming them as in this picture. NOTE: It may be helpful to just download the group tracker code here and copy and paste this into the "trackers" section of the vizconnect file in the VIzard editor.
5. On the avatars tab add a new avatar (can choose one of the included ones or use a Complete Characters avatar by choosing imported character). Click on the animator to assign each of these group trackers to animate the corresponding avatar body part.
6. Adjust the offsets on the right and left hand by clicking on the “offsets” button in the trackers if necessary
7. Save this vizconnect file and then navigate to the “postinit” section of the vizconnect and add the following code, replacing “Anthony” with the name returned from your Optitrack skeleton from the Vizard file you were using earlier and the body parts with the ones that were printed out as well:
optitrack = viz.add('optitrack.dle')
motive = optitrack.addMotive('localhost')
head = motive.getSkeleton("Anthony").getBody("Anthony_Head")
leftForearm = motive.getSkeleton("Anthony").getBody("Anthony_LFArm")
rightForearm = motive.getSkeleton("Anthony").getBody("Anthony_RFArm")
leftHand = motive.getSkeleton("Anthony").getBody("Anthony_LHand")
rightHand = motive.getSkeleton("Anthony").getBody("Anthony_RHand")
leftCalf = motive.getSkeleton("Anthony").getBody("Anthony_LShin")
rightCalf = motive.getSkeleton("Anthony").getBody("Anthony_RShin")
leftFoot = motive.getSkeleton("Anthony").getBody("Anthony_LFoot")
rightFoot = motive.getSkeleton("Anthony").getBody("Anthony_RFoot")
pelvis = motive.getSkeleton("Anthony").getBody("Anthony_Hip")
vizconnect.getTracker('optitrack_head').setRaw(head)
vizconnect.getTracker('optitrack_leftforearm').setRaw(leftForearm)
vizconnect.getTracker('optitrack_rightforearm').setRaw(rightForearm)
vizconnect.getTracker('optitrack_lefthand').setRaw(leftHand)
vizconnect.getTracker('optitrack_righthand').setRaw(rightHand)
vizconnect.getTracker('optitrack_leftcalf').setRaw(leftCalf)
vizconnect.getTracker('optitrack_rightcalf').setRaw(rightCalf)
vizconnect.getTracker('optitrack_leftfoot').setRaw(leftFoot)
vizconnect.getTracker('optitrack_rightfoot').setRaw(rightFoot)
vizconnect.getTracker('optitrack_pelvis').setRaw(pelvis)
8. If adding an avatar manually, you may need to change the code for using vizfx using this code
9. Add this vizconnect file to your Vizard scene as your normally would:
import viz
import vizconnect
vizconnect.go('vizconnect_config_optitrack_template.py')
env = viz.add('dojo.osgb')
Here also is a vizconnect file you can download that has this setup (but you may need to rename the skeleton parts based on the Optitrack skeleton you're using. You can also replace the avatar with one of your own, but then need to remap the trackers in the "animator" button under avatars.
If you are having orientation issues, you can do a calibration in vizconnect, by going to your vizconnect- Advanced - Avatars- Mappings and then map a button to the "calibrate" action. To calibrate, face virtual north while in a T-pose in Optitrack and press whatever key you have assigned to calibrate from your vizconnect file.
Mixamo is a free online library for avatars and animations that will also let you upload your own avatar in a T-Pose that can be automatically rigged to a Mixamo skeleton that can be used in Vizard.
Auto-rig an avatar using Mixamo’s auto-rigging https://helpx.adobe.com/creative-cloud/help/mixamo-rigging-animation.html
Go to mixamo.com
Select “Upload Character” or download one of the included avatars
Open Motionbuilder and add your Mixamo character using File-Open
On the right click on define Skeleton, then Click on hip bone in window and hip joint on Mixamo character
Click on the Template folder and choose HIK
Click to lock the definition
Rename character under the character menu- Edit- Definition- Rename
Add an FK/IK control rig by doing to Source- Control Rig- FK/IK
Drag in the Optitrack Skeleton, check online and create a new skeleton (according to instructions above)
Change character to your Mixamo character
Source to Optitrack
Choose to enable recording in the Optitrack plugin
Playback your Optitrack data and press record, choose overwrite and press play to record
Go to the character menu and choose Bake(Plot)- Plot to skeleton
Choose File- Motion File export
Open your character in Vizard’s Inspector, click on the name of the avatar and on the right under “animations” right click to import the animation you just exported
Save your character in Inspector to a .osgb file
In Vizard you would access the new animation using the following code where “state” is the number of the animation you imported
import viz
import vizfx
viz.go()
avatar = vizfx.addAvatar(‘nameofAvatarFile.osgb’)
avatar.state (1)
First you will need to download and setup Vizard Live Characters following this tutorial
Download and install Optitrack plugin for Motionbuilder
Open Motionbuilder and drag in Optitrack- Skeleton plugin (from Devices)
Select “Online”, “Live” and then Create a new skeleton. Make sure “Auto-Characterize” is selected
Drag in Vizard Live Character (FBX- Merge- No Animation)
Change Character to “Male” and Source to Optitrack skeleton
Drag in Live Characters plugin under “Devices”
Change character to “Male” and check “online”
Check “Recording” on the Optitrack plugin
Press the record button to enable recording (first change frame rate to 90?)
Press play to start recording
Toggle off “Online” and “Live” in Optitrack and press play to check recording
Trim frames if necessary for looping
Choose “Open Reality” export and change character to “male” and set frames to 90
Save animation in the animations folder of your Complete Character
Edit the .cfg file for the Complete Character and add the animation by right clicking on the .cfg file and editing in notepad
Open in Inspector to check
In Vizard you would access the new animation using the following code where “state” is the number of the animation you imported
import viz
import vizfx
viz.go()
avatar = vizfx.addAvatar(‘nameofAvatarFile.osgb’)
avatar.state (1)
To stream to Vizard using Live Characters, setup Live Characters according to this tutorial and use the following code in Vizard
import viz
import vizfx
import vizmocap
viz.go()
env = vizfx.addChild('tech_lab.osgb')
avatar1 = vizfx.addAvatar('guy1.osgb')
lcl = vizmocap.LiveCharacter('localhost', 8050, 8055,model= avatar1)
