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Hi guys,
I'm currently working on my own rig (with a scaled version first, thanks 3D printing
).
I'm going to skip the rig presentation for now as it's still in a very draft-ish state.
But basically I'd like to dedicate yaw axis for rear-wheel loss feeling, aka low side but also high-sides (in a limited way...).
For that I'm thinking to use some pinion & curved rack for rig's rear side.
Referring to official gpb_example.c, m_fYaw is the variable I was expecting to use.
Although pitch and roll data from telemetry can directly be used on the rig axis, unfortunately yaw axis data seems to be not that interesting for sensing the loss of grip on the rear wheel. Looks like this tells what is the relative orientation of our motorcycle chassis against the track map.
That actually makes sense of course, but I was thinking naively it could be used for my yaw effect purpose.
So I have tried to look at other variables from telemetry:
- rotation matrix: As explained in UDP Proxy thread, this seems to be just another shape for presenting yaw/pitch/roll data, so just an alternative to m_fYaw, m_fPitch & m_fRoll.
- m_fYawVelocity: Based on my personal understanding, this value seems to be the derivative of YAW position (i.e. m_fYaw).
When I put myself (voluntarily or not
) to lose the rear, I do see this value becoming higher than on a regular turn without losing grip.
However, how strong is the turn is also affecting this value without even losing the rear, and therefore I don't think I could use this as a "flag" or reference.
- m_afWheelSpeed: So far so good, this is the only variable where I consistently see a delta becoming greater when I lose the rear.
In normal condition (straight line or slight turn), I only have a delta of 1 or 2 at the max between front & rear wheel speed.
However when I start to feel I lose the rear, I can easily see in telemetry a gap/delta of ±8 between front & rear.
Again, it's not a consistent gap, just a greater one than usual.
- Eventually, maybe by crossing m_fPosX & m_fPosY and/or their velocity with m_fVelocityX & m_fVelocityY, against yaw velocity I could make a delta that express somehow the "instantaneous" yaw moment of the chassis, relatively to its center point on the track. Would that make sense?
Aside these paths, I'm a bit lost right now to know how to detect such "event" with a graduation scale.
Thanks in advance for anyone trying to provide some help
EDIT: Got a suggestion from poupou59890: he had a good idea of using steering angle as a trigger/reference to know whether rear side is sliding or not.
So far so good, I think this is the best option for now. I have quickly rechecked some in-game video footage + telemetry aside and that seems usable.
However one should add some linear/exponential/logarithmic factor that would moderate this effect when we run a low speed (hairpin bend turn).
However I'm still open to any advice, idea, suggestion, etc from anyone !
I'm currently working on my own rig (with a scaled version first, thanks 3D printing
).I'm going to skip the rig presentation for now as it's still in a very draft-ish state.
But basically I'd like to dedicate yaw axis for rear-wheel loss feeling, aka low side but also high-sides (in a limited way...).
For that I'm thinking to use some pinion & curved rack for rig's rear side.
Referring to official gpb_example.c, m_fYaw is the variable I was expecting to use.
Although pitch and roll data from telemetry can directly be used on the rig axis, unfortunately yaw axis data seems to be not that interesting for sensing the loss of grip on the rear wheel. Looks like this tells what is the relative orientation of our motorcycle chassis against the track map.
That actually makes sense of course, but I was thinking naively it could be used for my yaw effect purpose.
So I have tried to look at other variables from telemetry:
- rotation matrix: As explained in UDP Proxy thread, this seems to be just another shape for presenting yaw/pitch/roll data, so just an alternative to m_fYaw, m_fPitch & m_fRoll.
- m_fYawVelocity: Based on my personal understanding, this value seems to be the derivative of YAW position (i.e. m_fYaw).
When I put myself (voluntarily or not
) to lose the rear, I do see this value becoming higher than on a regular turn without losing grip.However, how strong is the turn is also affecting this value without even losing the rear, and therefore I don't think I could use this as a "flag" or reference.
- m_afWheelSpeed: So far so good, this is the only variable where I consistently see a delta becoming greater when I lose the rear.
In normal condition (straight line or slight turn), I only have a delta of 1 or 2 at the max between front & rear wheel speed.
However when I start to feel I lose the rear, I can easily see in telemetry a gap/delta of ±8 between front & rear.
Again, it's not a consistent gap, just a greater one than usual.
- Eventually, maybe by crossing m_fPosX & m_fPosY and/or their velocity with m_fVelocityX & m_fVelocityY, against yaw velocity I could make a delta that express somehow the "instantaneous" yaw moment of the chassis, relatively to its center point on the track. Would that make sense?
Aside these paths, I'm a bit lost right now to know how to detect such "event" with a graduation scale.
Thanks in advance for anyone trying to provide some help
EDIT: Got a suggestion from poupou59890: he had a good idea of using steering angle as a trigger/reference to know whether rear side is sliding or not.
So far so good, I think this is the best option for now. I have quickly rechecked some in-game video footage + telemetry aside and that seems usable.
However one should add some linear/exponential/logarithmic factor that would moderate this effect when we run a low speed (hairpin bend turn).
However I'm still open to any advice, idea, suggestion, etc from anyone !