Guys, let me know how I can calculate the speed in km / h of each wheel on the BT20. Telemetry me alone revolutions per minute to radians per second, so where do I find the diameter of the wheels? Ps it is possible that the rear tires are smaller than the front? If someone can answer that question I am infinitely grateful!
The bad news is that you can't. The only speed that you can get is vehicle speed, not individual wheel speed. See here for more details... http://isiforums.net/f/showthread.p...ssing-wheel-diameter-velocities-not-populated
wheel rotational speed and damper velocities are exported to motec. Not sure what you guys are talking about. Look at the right side maths slider in motec. They are in there. View attachment 6044 View attachment 6045
Sorry, but for the Wheel Speeds the values in MoTec are incorrect. The only wheel speed data available via the plugin is mRotation, which is defined as radians/sec. There is a helpful conversion available so you can get deg/sec but unless you have the wheel radius or diameter it is impossible to convert these values to speed. The plugin also makes available a parameter that shows how much is tire deflected from its (speed-sensitive) radius, but again you need the radius to fully use this value. I have made a request before to have the tyre radius information available in the plugin, but this is not yet available. Regarding the damper velocity, this data is also not directly available via the plugin, only the suspension deflection and ride height at each wheel. As the sampling rate is know, it is possible to convert these values (via a maths function) to a damper velocity. Please let me know if I have missed something. View attachment 6046
Should wheel radial size be implemented to calculate wheel speed it could be used for cheating. If this information was available to me I could easily make a plugin to control braking with my own advanced abs of sort if you like. I was going to originally build an 4 LED blinker for which tyres where locking if this info was available. I dont think its a good idea this be implemented, so please dont even request it. However with a bit of clever math using vehicle speed and wheel rads per sec you could get a rough estimate of what you want.
When the controlling input is not available to modulate via plugin, how is it now that you can cheat with a custom ABS plugin by only knowing a proper wheelspeed? As was mentioned clever maths get you wheelspeed already. I don't buy the slippery slope logic. The radius of the wheel (more or less) is still in the TBC files.
He may have been talking about a custom macro for his controller to detect wheel spin or wheel lockup and adjust the input numbers from his controller.
There is a telemetry software coming out soon that has 27 game support including rF2. I can't say much about it right now but its not long till its released.
Adding the wheel radius will not change anything in that respect. You don't need the radius of the wheel to detect if it is locked... So that's not a reason not to add it. The angle velocity is enough to make your led locking thingy.
Automotive (and motorsport) based ABS electronic systems are based on wheel speed rate of change rather then the absolute speed, with the current plugin information it is easily possible to make an ABS warning system, however without the plugin accepting input controls it would not be possible to implement a system for cheating. My original request was made to have the wheel radius information available in the plugin so that I do not have to go parsing through files trying to find the detail for each car (although I may implement that now as a short term measure). Although it is possible to roughly calculate the radius (for example by completing a coast down test with no brake or throttle applied against a range of speed), it is not realistic to do this because the effects of tyre wear etc will change the result. Just about every modern car has the wheel speed information available via the ECU, and a wheel speed sensor is just about the first sensor added to any racing vehicle so I would like the data available in the plugin if possible, after all RF2 is a simulator and not a game....
Not trying to be smart or anything (first, I have no such talent, and second, I don't know how this works so I can't be trying to set you up), but how does a real ECU know the actual wheel speed? If there are multiple variables affecting the angular velocity vs actual ground speed relationship (effective radius incorporating wear, load, ... , and whatever else might influence the reading) wouldn't the only true measure be a measuring wheel against the surface of the tyre? So an ECU would need to make some calculations of a similar nature to you, given the lack of an actual ground speed? I honestly don't know. Just that right now I can't see how you'd know the tyre speed of a real car, unless you're directly measuring (physically or perhaps optically) the tread speed past a point. You could probably get quite a close estimate by monitoring the current sliding percentage so that you can have more confidence in the current vehicle speed vs wheel rotation. Bit messy no doubt. If and when those 4 data values are populated (lat and long ground and patch velocities) you'll be all set
I am not even sure that modern vehicles have wheel speed. The ABS systems in real cars is based on sensors in the hub or on the axle stub that read rotational speed and compare each corner to determine if one or more wheels are locking. The system also looks at acceleration of the speed or deceleration to determine if all 4 wheels are affected. The same sensors could be used to determine TC settings as well. Those sensors are usually hall effects sensors, but there are likely other types of sensors out there as well. The only system in a car that needs to have anything related to wheel speed would be the speedometer, and that isn't really reading wheel speed, it is reading transmission output speed and is calibrated to the size of the tire on the vehicle by changing gears on the drive for the speedometer. Electronic sensing speedometers would still use the transmission but use analog to digital converters at that transmission to feed the speedometer. This is why you have to get your speedometer calibrated if you change tire sizes.
They compare wheel rotation speeds, front and rear. In racing they also compare with GPS data. Edit: As you are interested in longitudal grip the rotation speed will give you the slip angle directly and that is what is interesting to optimize the grip.
For wheel spin you could try this in expressions in MoTeC: Name: Wheel Spin Front (Skid) Quantity: Ratio Display Unit: percent (%) Result Unit: percent (%) Expression: choose('Corr Speed' [km/h] > 50, (('Corr Speed' [km/h] / (('Wheel Speed FL' [km/h]+'Wheel Speed FR' [km/h])/2)) * 100)-100, 0) Name: Wheel Spin Rear (Slip) Quantity: Ratio Display Unit: percent (%) Result Unit: percent (%) Expression: choose('Corr Speed' [km/h] > 50, (('Corr Speed' [km/h] / (('Wheel Speed RL' [km/h]+'Wheel Speed RR' [km/h])/2)) * 100 - 100) * -1, 0)
Exactly what I was saying The size of the tire isn't required to determine rotational speed, just a fixed point and a rotational point anywhere on the wheel or axle for each corner.
