Pryo
05-10-2009 16:44:04
I am trying to model a car using the Vehicle prefab. Mostly it works very well, particularly at slow speed.
My main problem is that the steering seems to take on a life of its own in certain situations. The first thing I notice is that the steering seems to automatically adjust depending on how fast the car is moving. As the speed increases, you can no longer steer the wheels to the stop. Instead, at top speed, the wheels only angle slightly when holding down left, or right on the keyboard. This isn't so much of a problem because it is an effect I would like to see anyway. The problem is I cant see where this effect is being computed. From my reading of the source code, the steering column should be doing "exactly as it is told".
Also, when the car is starting to slide sideways, the wheels tend to "automatically" steer into the slide. This is a big problem. More generally, at high speed it seems that the wheels steer away from the direction that the car body is turning. I want the car to behave like a real car, in that even significant forces applied to the wheels from the world will have only a very slight effect on the steering column or none at all.
My best guess about why this is happening is that the angular momentum of the wheels is introducing a gyroscopic force that tries to maintain the axis of rotation of the wheels. I have tried to overcome this by two methods. Firstly I have tried increasing the "steering force". Annoyingly, beyond a certain point this parameter has no effect. I can make the steering behave in a far more loose manner, but I can't seem to tighten it up by increasing this force. Secondly I have tried reducing the mass of the wheels. The only effect this has is to make the wheels start jumping around in an erratic manner which makes no sense as far as I can see. The "automatic steering" effect remains unaffected.
Does anyone have any suggestions at all?
Thanks a lot.
My main problem is that the steering seems to take on a life of its own in certain situations. The first thing I notice is that the steering seems to automatically adjust depending on how fast the car is moving. As the speed increases, you can no longer steer the wheels to the stop. Instead, at top speed, the wheels only angle slightly when holding down left, or right on the keyboard. This isn't so much of a problem because it is an effect I would like to see anyway. The problem is I cant see where this effect is being computed. From my reading of the source code, the steering column should be doing "exactly as it is told".
Also, when the car is starting to slide sideways, the wheels tend to "automatically" steer into the slide. This is a big problem. More generally, at high speed it seems that the wheels steer away from the direction that the car body is turning. I want the car to behave like a real car, in that even significant forces applied to the wheels from the world will have only a very slight effect on the steering column or none at all.
My best guess about why this is happening is that the angular momentum of the wheels is introducing a gyroscopic force that tries to maintain the axis of rotation of the wheels. I have tried to overcome this by two methods. Firstly I have tried increasing the "steering force". Annoyingly, beyond a certain point this parameter has no effect. I can make the steering behave in a far more loose manner, but I can't seem to tighten it up by increasing this force. Secondly I have tried reducing the mass of the wheels. The only effect this has is to make the wheels start jumping around in an erratic manner which makes no sense as far as I can see. The "automatic steering" effect remains unaffected.
Does anyone have any suggestions at all?
Thanks a lot.