Frank 993 C4S

Help !! I am looking to calculate tires loads over a particular lap with AIM math channels. For that I have shock pods, know the spring rate and with a math channel can correlate the shock pod displacement with actual height changes which allows me to calculate actual downforce changes per wheel.

What I am now looking to do is calculate the total dynamic load per wheel per lap, however I am only looking to calculate the integral over the positive values load values (negative load values correspond to unloading of the particular wheel). The lap_integ function in AIM just takes all of the positive and negative values into account over a lap and I would like for it to consider the positive values only.

Thoughts?

Matt Romanowski

You should be able to do a lap integral with a nested if and less than statement. Something like

lap_integ(IF(LT(shock pot,0.001),shock pot,0))

Frank 993 C4S

Thank you Sir! Much appreciated.

Matt Romanowski

That should have been a GT not a LT. Also, mind the leading zeros.

Frank 993 C4S

Matt, for some reason I can't get it to work. The "(left_front_sho+0.4)/25.4*700)" is the load calculation.

lap_integ(IF(GT((left_front_sho+0.4)/25.4*700),0),(left_front_sho+0.4)/25.4*700),0))

Matt Romanowski

I think you have 2 problems. First, your math is making really small numbers, so they don't display right. Second, you have a parenthesis problem. I broke it into 2 channels.

Load
(RR_Shock_Senso+0.4)/(25.4*700)*1000000

Integral
lap_integ(IF(GT(load, .001),load,0))

This works once you put in multiply by 1000000. Without that, the values are too small. The integral gives you a sum total of the values. If you do a channel report and take the maximum, it will give it to you for each lap.

Frank 993 C4S

Thanks! Let me try that out. Will report back!

Frank 993 C4S

Thank you - got it to work. This chart now shows the dynamic loading differential (front left tire) at Watkins Glen between my old car and my new car - a massive difference about 73% higher! The new car accelerates a little faster and I've learnt to brake a little better, not lift in the Esses and cary higher min speeds

Chris P Lewis

Fast car. I saw 148.3 MPH. I got a total of about 5 clear laps. My fastest laps were all balked by someone or something.. (double yellows) Congrats on your very fast weekend.
Chris

Frank 993 C4S

Thanks Chris! T1 Min Speed of 75+ mph is critical to a good top speed into the Bus Stop.

ProCoach

^^Bingo^^ Much higher than the average vMin for most cars.