In this video, I like to talk about
a super strong but slightly weird illusion you could have in VR.
The possibility of being somewhere else inside the HMD.
To explain this idea,
I will need to first go back to the two VR systems we are very familiar with.
When I'm in the cave-like system,
I can see virtual objects projected on the screen and I can also
see through the shutter glasses any real objects that are inside the cave.
That includes my own body.
So when I look down,
I see my body and when I reach out to interact with an object,
or when I gesture with my friends,
I can see my own hands.
In the HMD, on the other hand,
I am entirely blocked from the real world.
So I can be deeply immersed in VR and feel that I am really somewhere else.
But with lots of the applications of HMD,
the moment I look down or reach forward with my hands,
I would suddenly realize that something is
missing because my brain automatically looks for my body,
which is no longer there.
For me, this is like a switch being flipped.
From that moment on,
I still feel that I'm immersed in a different world,
but I don't feel that anything in the virtual world is as relevant anymore.
There is a simple fix to this problem.
You just need to give the user a self avatar.
And if you manage to put it where the user expect their body to be,
this will have a very strong effect.
It will give the user a Proprioception Match.
Proprioception here means someone's overall sense
of the relative position of their own parts of the body.
However, it might still be a good idea to tell the user to sit or stand in a fixed pose.
This is because if they start moving their body and
notice that their virtual body remains still,
it will break the illusion.
If you can afford a more sophisticated setup,
then you can animate a body to move in the same way the user does.
In this case, the user can see
their self avatar as if he's in the mirror in front of them,
and when they put their hands in front of themselves,
they can also see them.
This setup is supported by a Kinect sensor.
A similar effect can also be supported by
the VR controllers using their position rotation tracking data.
Assuming users are holding the controllers with their hands,
we can easily render a pair of hands where the controllers are.
This will give user the strong illusion of seeing their own hands.
You can do the same with 360 degree video.
You strap your camera rig to someone and record the footage with them inside video.
But like everything else in 360 video,
you're stuck with what you have captured.
If the footage is obviously recorded with a female body,
then it is not something you can easily change.
You also can't animate a body to make it match your own movements.
So in most VR applications,
it helps to at least have a static body where users expect their own body to be.
So they feel that what happens in VR is physically relevant to them.
This also enables us to do something even more interesting.
To use Professor Mel Slater's words,
VR can transform not only where you are but who you are.
Because we can easily change the appearance and shape of our virtual body,
we can choose to be somewhere else in VR.
For instance, I have experienced being somewhere in VR with a different body shape,
or a different gender,
or from a different ethnic group.
Those experiences have been proven to have
very interesting and long lasting psychological effects on people.
We will discuss more about that later in this course.