Plugin Real Head Motion

Personnal Video Game industry Background

I'm Ingenior Developer in video game industry since 1998.
V-Rally 2 ( PS1-DC-PC) :  A.I., In Game Track Editor & Track generator.
Need For Speed Porsche Unleashed ( PS1 ) : A.I., GFX, Licence test system
V-Rally3 ( PS2-XBOX-PC ) : Collision and Dynamic Engine, Device Enginne, Car Physics, GFX.
Test Drive Unlimited ( X360-PC ) : Car Physics , Replay system, Camera System, Devices.


Why this plugin?

The camera shaking in rF2, is very bad, it give nausea, make the viewing of the track difficult and it's not even realistic of what a drive see when he drives.


Biological facts

The feel of equilibrium, acceleration, gravity, and so bumps are not feel by the eye but with the inner hear. Wich is made of liquid and crystals.

When the inner hear feels bumps and head motion, it instintly moves your eyes to soften/filter/remove those bumps.

2 experiences to demonstrate that.
1) when put somebody on a chair, in complete dark, you film his eyes with an infrared caemras, you turn the chair, is eyes will roll too, even if he see nothing

2) this one you can do it yourself, looks at in front of you, at your screen, not shake your head, the vision will not move.

When there is conflicting information from inner hear and eye, you feel strange, it's difficult to focus on the road, and you can have nausea.

What happens in a car

When you are driving, you are looking the road, and all the bumps are filter/corrected by your inner hear, so the viewing of the track is smooth and it's the car cockpit that moving around you.

What happens in a Sim

Because you are sitting and a standing chair/seat, you head is not moving at all, so the inner ear is not working, the eye don't correct the bumps.
That's make 2 issues :
1) you can't focus on the road, the road is shaking and not smooth, it's difficult to drive
2) you can get nausea because you have conflicting information from eyes and inner hear.

How it should be in a Sim

Instead of having the head/eye moving around the cockpit, it should be the cockpit that move around the point of view.

How to do this

Simulation the head motion and the eye motion.

Head Motion :
Head is pushed by G forces, and the neck muscles are counter acting to keep the head straight in the horizon, but the horizon is not the world horizon. If the car is keep leaned a certain amount of time the brain will choose another horizon. For example, NASCAR drivers don't keep the head straight, thye lean into the banking track. So this part is quite difficult to get it right.
I choosed to have an horizon that tend to follow the car "horizon" with a filtering and smoothing, I called it head horizon.
So when the car is changing of pitch/roll rapidly, the head horizon is almost not changing, but when the car is constantly leaning, the head horizon will match car horizon smoothly.
Additionally I could further add things like, ahead yaw apex targeting, inner turn lean when driver try to counter lateral G forces,etc. But I think this something we do instintivly ourself in front of our screen ;)

Eye Motion:
The inner ear is moving the eye inconsiently to stablize the view, it void smalls translations and rotations of the head in the world coordinate, so the vision remain clear.

Latest Version
  1. Inner ear simulation that try to stabilize the view with moving head and eyes.
  • Pitch
  • Roll
  • Speed Factor
  • High Angle Factor
  1. G-Force simulation
  • Pitch
  • Roll
  • Forward Translation
  • Vertical Transaltion
  1. Default Head Position
  • Pitch
  • Translation