Steering Angle Setup
#1
Steering Angle Setup
I'm running a Solo DL and RS2. I thought I'd take a look at steering angle and viewed it on the measures screen. Scale was preset to 1500 degrees so I changed it to 90. Looking at the plot I see everything going in one direction and using up most of the 90 degree range. I definitely doing something wrong, advice please. Thanks.
#2
I'm not sure what to tell you about what you see but I can confirm that with my SoloDL, hooked up over CAN, I get the steering wheel angle trace (PSH_STEER_POS) and can see values plus and minus. I set my scale to max "165" and min "-165" in the "measure information" dialog.
You remind me to ask a related question though...for some other math channels it would be more useful to have "steered angle" (which is to say the direction the wheels are actually pointed relative to car centerline). My car is a 991TT and has a steering ratio labeled as "Variable 12.25:1 - 15.02:1" in the specs. Is there some way to extract accurate steered angle??
Right now I'm interpolating on a best-guess basis and eyeballing the fact that if you look on the PCM screen it will tell you the steered angle in one of the info screens so I have some idea of what the translation is. It's a bit of a hack though so if anyone reading this thread knows how to get proper steered angle data I'd be glad of a shove in the right direction
You remind me to ask a related question though...for some other math channels it would be more useful to have "steered angle" (which is to say the direction the wheels are actually pointed relative to car centerline). My car is a 991TT and has a steering ratio labeled as "Variable 12.25:1 - 15.02:1" in the specs. Is there some way to extract accurate steered angle??
Right now I'm interpolating on a best-guess basis and eyeballing the fact that if you look on the PCM screen it will tell you the steered angle in one of the info screens so I have some idea of what the translation is. It's a bit of a hack though so if anyone reading this thread knows how to get proper steered angle data I'd be glad of a shove in the right direction
#3
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I'm running a Solo DL and RS2. I thought I'd take a look at steering angle and viewed it on the measures screen. Scale was preset to 1500 degrees so I changed it to 90. Looking at the plot I see everything going in one direction and using up most of the 90 degree range. I definitely doing something wrong, advice please. Thanks.
#4
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From: Manchester, NH
I'm not sure what to tell you about what you see but I can confirm that with my SoloDL, hooked up over CAN, I get the steering wheel angle trace (PSH_STEER_POS) and can see values plus and minus. I set my scale to max "165" and min "-165" in the "measure information" dialog.
You remind me to ask a related question though...for some other math channels it would be more useful to have "steered angle" (which is to say the direction the wheels are actually pointed relative to car centerline). My car is a 991TT and has a steering ratio labeled as "Variable 12.25:1 - 15.02:1" in the specs. Is there some way to extract accurate steered angle??
Right now I'm interpolating on a best-guess basis and eyeballing the fact that if you look on the PCM screen it will tell you the steered angle in one of the info screens so I have some idea of what the translation is. It's a bit of a hack though so if anyone reading this thread knows how to get proper steered angle data I'd be glad of a shove in the right direction
You remind me to ask a related question though...for some other math channels it would be more useful to have "steered angle" (which is to say the direction the wheels are actually pointed relative to car centerline). My car is a 991TT and has a steering ratio labeled as "Variable 12.25:1 - 15.02:1" in the specs. Is there some way to extract accurate steered angle??
Right now I'm interpolating on a best-guess basis and eyeballing the fact that if you look on the PCM screen it will tell you the steered angle in one of the info screens so I have some idea of what the translation is. It's a bit of a hack though so if anyone reading this thread knows how to get proper steered angle data I'd be glad of a shove in the right direction
#5
MAXSTEERRATIO = 12.25
MINSTEERRATIO = 15.02
steering ratio = IF(LT(GPS_Speed,37),MAXSTEERRATIO, IF(GT(GPS_Speed,75),MINSTEERRATIO, (MAXSTEERRATIO - ((GPS_Speed-37)/(75-37) * (MAXSTEERRATIO - MINSTEERRATIO)))))
MINSTEERRATIO = 15.02
steering ratio = IF(LT(GPS_Speed,37),MAXSTEERRATIO, IF(GT(GPS_Speed,75),MINSTEERRATIO, (MAXSTEERRATIO - ((GPS_Speed-37)/(75-37) * (MAXSTEERRATIO - MINSTEERRATIO)))))
approx steered angle = (-PSH_STEER_POS / Steering Ratio)
#6
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From: Manchester, NH
Well, I don't know if it's "fancy" but this is what I have right now:
and
So yeah, the 37/75 mph breakpoints above are guess work that would benefit from better information about the schedule of steering input to output. I'd certainly guess that linear interpolation like that should really be a curve function of some sort to match the actual behavior. I have not been able to come up with that sort of info about how the in-car implementation actually works though.
and
So yeah, the 37/75 mph breakpoints above are guess work that would benefit from better information about the schedule of steering input to output. I'd certainly guess that linear interpolation like that should really be a curve function of some sort to match the actual behavior. I have not been able to come up with that sort of info about how the in-car implementation actually works though.